Next Article in Journal
The Quantification of IgG Specific to α-Gal Could Be Used as a Risk Marker for Suffering Mammalian Meat Allergy
Next Article in Special Issue
Towards the Use of Natural Compounds for Crop Protection and Food Safety
Previous Article in Journal
Plant and Dairy-Based Yogurts: A Comparison of Consumer Sensory Acceptability Linked to Textural Analysis
Previous Article in Special Issue
In Vitro Potential of Clary Sage and Coriander Essential Oils as Crop Protection and Post-Harvest Decay Control Products
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:

Essential Oils and Their Major Components: An Updated Review on Antimicrobial Activities, Mechanism of Action and Their Potential Application in the Food Industry

Food Science, School of Chemical Sciences, The University of Auckland, Auckland 1010, New Zealand
Faculty of Medical and Health Sciences, School of Medical Sciences, The University of Auckland, Auckland 1010, New Zealand
The New Zealand Institute for Plant & Food Research Limited, Palmerston North 4442, New Zealand
Riddet Institute, New Zealand Centre of Research Excellence for Food Research, Palmerston North 4474, New Zealand
Author to whom correspondence should be addressed.
Foods 2022, 11(3), 464;
Submission received: 8 January 2022 / Revised: 28 January 2022 / Accepted: 3 February 2022 / Published: 4 February 2022


A novel alternative to synthetic preservatives is the use of natural products such as essential oil (EO) as a natural food-grade preservative. EOs are Generally Recognized as Safe (GRAS), so they could be considered an alternative way to increase the shelf-life of highly perishable food products by impeding the proliferation of food-borne pathogens. The mounting interest within the food industry and consumer preference for “natural” and “safe” products means that scientific evidence on plant-derived essential oils (EOs) needs to be examined in-depth, including the underlying mechanisms of action. Understanding the mechanism of action that individual components of EO exert on the cell is imperative to design strategies to eradicate food-borne pathogens. Results from published works showed that most EOs are more active against Gram-positive bacteria than Gram-negative bacteria due to the difference in the cell wall structure. In addition, the application of EOs at a commercial scale has been minimal, as their flavour and odour could be imparted to food. This review provides a comprehensive summary of the research carried out on EOs, emphasizing the antibacterial activity of fruit peel EOs, and the antibacterial mechanism of action of the individual components of EOs. A brief outline of recent contributions of EOs in the food matrix is highlighted. The findings from the literature have been encouraging, and further research is recommended to develop strategies for the application of EO at an industrial scale.

1. Introduction

Antimicrobial agents used to kill or inhibit the growth of pathogenic or food spoilage bacteria can exist in natural or synthetic forms. The use of synthetic antimicrobial compounds as food preservatives has raised consumers’ concerns, since they present numerous toxicological difficulties and may not be safe for human consumption [1]. Hence, over the last two decades, natural antimicrobial agents such as essential oils (EOs) have received renewed interest from the scientific community, owing to their unique physicochemical properties and diverse biological activities [2]. In the definition coined by Rios [3], EOs are aromatic, oil-like volatile substances present in plant materials such as fruits, bark, seeds, pulp, peel, root and whole plant. These substances form in the cytoplasm, and generally exist as tiny droplets sandwiched between the cells. In recent years, increasing awareness about the “green, safe and clean” environment and a growing appeal for “green consumerism” have prompted the production of foods free of synthetic preservatives [4,5].
EOs have been used for medicinal purposes and as therapeutic agents since ancient times [6]. Although food industries utilize EOs as a flavoring agent, their potential as a natural food grade preservative has not been fully explored. EOs present a valuable tool for food preservation due to their natural antimicrobial properties [7]. However, a detailed understanding regarding individual components of EOs, their antibacterial properties, mechanism of action and target organisms is required to support the implementation of EOs as food preservatives. Calo et al. [8] reported that EOs comprise numerous compounds such as aromatic hydrocarbons, terpene (monoterpenes and sesquiterpenes), terpenoids, esters, alcohols, acids, aldehydes and ketones, and their antibacterial activity is not solely contributed by any one compound. Recognizing the most potent antibacterial compounds from EOs is often tricky due to their chemistry complexity. To date, most studies have focused on studying the antimicrobial activity of EOs [5,8], with little discussion on the antibacterial activity of individual components in the EO or their mechanism of action. The antibacterial activity of EOs is not reliant on one specific mode of action; instead, EOs can attack several targets in a cell to inactivate the bacterium [7]. Evaluating EO’s antibacterial properties and mechanism of action of their components may provide new insights into their applications in the food industry. This approach may reveal the concealed antibacterial properties of individual EO components, otherwise masked when EOs are studied as one single substance.
Several reviews [2,9,10] have outlined the antimicrobial activity of EOs extracted from various plant sources such as stem, bark, leaf, fruit, and seeds, but did not discuss the waste parts such as peel. The amount of waste produced by fruit processing industries is diverse [11]. Fruit peels generated by food industries are treated as agro-waste and are discarded in landfills, composted or fed to livestock [12]. Fruit waste produced in enormous quantities during commercial processing could present severe environmental threats [13]. Ayala-Zavala et al. [14] proposed using fruit by-products as an antimicrobial food additive, reporting that mandarins, papayas, pineapple, and mangoes accounted for 16.05%, 8.47%, 13.48% 11% of peel waste, respectively. On the other hand, fruit peel is a rich source of EOs and contains promising novel components of potential pharmacological, pharmaceutical and economic significance [13]. Moreover, fruit peel EOs are classified as GRAS (generally recognized as safe) and can be used to improve food safety due to their unique antimicrobial properties [15].
Studies on EOs extracted from various plant sources are well represented in the literature, and it is widely recognized that EOs possess a range of biological activities. For instance, EOs extracted from thyme [16], oregano, lavender [4,17], cinnamon, clove [18] and turmeric [19] have antibacterial, antifungal, algicidal, antioxidant, anticancer and anti-inflammatory activities. Chemical compositions and biological properties of plant EOs, in general, have been discussed in detail in reviews by Bakkali et al. [20], Burt [5] and Ju et al. [21]. A substantial amount of work has been carried out to evaluate the antimicrobial properties of EOs extracted from fruit peels; however, none of the reviews in the compiled data have exclusively discussed peel EOs. In light of these factors, this review aims to summarize the most significant findings of the antimicrobial properties of fruit peel EOs and their major components that contribute to microbial inactivation, with a focus on the mode of action of EO/EOs components. Finally, the application of various plant-derived EOs in the food industry is discussed, and future research directions and applications are presented.

2. Chemical Composition of Fruit Peel Essential Oils

Plants produce a variety of chemical compounds with antimicrobial properties. Some of these compounds are always present, while others are secreted in response to stress, such as infection, damage, predators, and weather variations. The chemical constituents in EOs are prone to variations depending on the time of harvest, cultivar, and the extraction method. Hydro distillation and steam distillation are frequently used to produce EOs at a commercial scale [5]. Identifying the most active compounds from EO can be a cumbersome process. Gas chromatography (GC), gas chromatography-mass spectrometry (GC-MS) [22,23,24], high-performance liquid chromatography (HPLC) [25,26,27] and liquid chromatography coupled to mass spectrometry (LC-MS) [28] are the most widely used methods to study the chemical composition of EOs. The primary chemical components of EOs are terpenes and polyphenols. Figure 1 shows the structural formula of some of the major components of EOs. These chemical compounds have been reported to have antimicrobial properties and their mechanisms of action are discussed later (Section 4).
Terpenes can be defined as a framework of numerous isoprene units (C5H8) merging to form a hydrocarbon molecule. They are derived from mevalonate and mevalonate-independent pathways [29]. Terpenes usually exist in EOs in the form of monoterpenes (C10H16) or sesquiterpenes (C15H24). However, other long-chain molecules such as diterpenes (C20H32), triterpenes (C30H48), tetraterpenes (C40 H64) are found in EOs in minor quantities [30]. Examples of terpene compounds include β-caryophyllene, p-cymene, α-pinene, β-pinene, limonene, sabinene, γ-terpinene, α-terpinene, β-myrcene, cinnamyl alcohol, and δ-3-carene. Additionally present are terpenoids, identified as an oxygenated derivative of terpene compounds with an additional oxygen molecule, or their methyl group being moved or eliminated. Terpenoids are further categorized into esters, aldehydes, ketones, alcohols, ethers, and epoxides, with examples including menthol, geraniol, eugenol, thymol, carvacrol, geraniol, linalyl acetate, linalool, citronellal, citronellol and terpineol [7,31].
Polyphenols are secondary metabolites widely distributed in nature, usually derived from the phenylpropanoid pathway [32]. Polyphenols can be categorized into phenylpropenes and flavonoids, based on the number of phenol rings [33]. Phenylpropenes have derived their name from the six-carbon aromatic phenol group, and the three-carbon propene tail of cinnamic acid formed during the first step of phenylpropanoid biosynthesis [34]. Flavonoids are a group of phenolic compounds with a carbon framework (C6-C3-C6). The basic skeletal structure of flavonoids comprises a 2-phenyl-benzo-γ-pyrone consisting of two benzene rings (ring A and ring B) cross-linked to a heterocyclic pyrone (ring C) [35]. Based on the degree of oxidation, flavonoids are further classified into flavones, flavonols, flavanones and others [36].
A detailed analysis of the EOs of orange peel identified an abundant amount of limonene, ranging between 73.9–97.6%, while other monoterpenic alcohols, namely geraniol, linalool, nerol and α-terpineol, were present in minor quantities at concentrations of 2.1%, 4.1%, 1.5%, 2.4%, respectively [24]. This finding was in agreement with Ambrosio et al. [22] and Guo et al. [37], who reported similar compounds in orange peel EOs. However, some compounds such as cis-p-mentha and trans-p-mentha [22,37] were not reported previously [24]. These differences could be attributed to the different cultivars or growing conditions of the fruit analyzed in these studies. Moreover, a close resemblance was noted in the limonene content of grapefruit peel EO, which was present at a concentration of 93.3% [23], 91.5% [38] and 91.8% [39]. Other monoterpene compounds such as β-myrcene, α-pinene, sabinene, linalool and thujene were also reported [23,38,39]. In pummelo peel EO, limonene contributed up to 55.7% of the total EO composition, followed by β-pinene (14.7%), linalool (6.2%), β-citral (4.1%), germacrene-D (2.7%), α-pinene (2.3%), α-terpineol (2.0%), geraniol (1.6%), sabinene (1.3%) [39]. Tao et al. [40] reported similar compounds but at a much lower concentration, ranging from 0.08% to 0.63%. The difference in the extraction method, such as using a rotary evaporator at 40 °C [38], could have contributed to the significant loss of highly volatile compounds from the EO. Furthermore, Hosni et al. [41] and Hou et al. [42] found limonene to be the main component in mandarin peel EO, but other secondary compounds such as lauric acid, 1-methyl-1,4-cyclohexadiene, methyl linoleate, myristic acid, palmitic acid and β-myrcene were reported only by Hou et al. [42]. More recent evidence [43] highlights that out of 158 compounds found in feijoa peel EO, 89 compounds identified were novel; these compounds include esters, sesquiterpenes, monoterpenes, aromatic hydrocarbons, alcohols, aldehydes, ketones, hydrocarbon, acids and ethers.
Limonene is the predominant component in the EOs of orange [22,24,37,41], grapefruit [23,39], mandarin and pummelo [39,40] peels, and is thought to contribute to most of the antimicrobial activity of the fruit peels reviewed above [44]. However, Ambrosio et al. [22] argued that limonene is present in different concentrations in different fruit peels; thus, the antimicrobial activity of EOs cannot be ascribed solely to limonene. Additionally, studies have reported low antimicrobial activity of limonene when the pure compound was tested [45]. Hence, in citrus fruits, other minor compounds such as α-pinene, sabinene, linalool, β-citral, and germacrene-D could contribute to the antimicrobial activity.

3. Antimicrobial Properties of Fruit Peel Essential Oils

The antimicrobial activity of EOs can be seen as the inhibition of cell growth or by cell-killing. However, it is not easy to differentiate between these modes of action. The antimicrobial efficacy of EOs is dependent on their chemical composition, environmental conditions and the structures of the target bacteria (either Gram-positive or Gram-negative bacteria) [46]. Numerous in vitro techniques [47], such as the determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) by broth macro dilution/microdilution or agar disk/well diffusion are applied to determine the efficacy of an antimicrobial compound. Agar disk/well diffusion and broth macro dilution/microdilution are widely used methods in clinical microbiology laboratories [48] and have recently been recognized as useful tools to determine the antimicrobial activity of EOs [49,50].
Many studies have illustrated the antimicrobial effect of fruit peel EOs against drug-resistant, pathogenic and food spoilage bacterial strains. Some studies have found that EOs extracted from the fruit peels of banana [13], pomegranate [1] and citrus fruits such as sweet orange, grapefruit, lime, sweet lemon, mandarin, tangerine and pummelo [22,40,51,52,53] exhibited inhibitory activity against Gram-positive and Gram-negative bacteria. These studies indicate that fruit peels are a potentially valuable anti-microbial resource [42]. A wide range of foodborne pathogens could be inhibited by fruit peel EOs, including Escherichia coli, Enterobacter cloacae, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella enterica serovar Typhimurium, Salmonella enteritidis, Bacillus subtilis, Bacillus cereus, Streptococcus faecalis, Listeria monocytogenes, Proteus vulgaris, Staphylococcus aureus and others (Table 1). An overview of the antimicrobial activity of various fruit peel EOs and detection methods over the last 15 years is presented in Table 1.

3.1. Citrus Essential Oils

Abd-Elwahab et al. [51] reported the efficacy of EOs extracted from citrus peels, i.e., orange, lime, mandarin, and grapefruit, as having moderate to high antibacterial activity against S. aureus, B. subtilis, E. faecalis, E. coli, Neisseria gonorrhoeae and P. aeruginosa. Among those citrus EOs, lime peel EO was the most effective at inhibiting all six strains of pathogenic bacteria. The presence of coumarine and tetrazene in lemon peel [13] and citral, limonene and linalool in other citrus peel EO [51] may have accounted for their antimicrobial activity against these bacteria. On the contrary, Javed et al. [15] reported that amongst all tested citrus peel EOs (mandarin, tangerine, sweet orange, lime, grapefruit) mandarin peel EO possessed the highest antimicrobial activity. The inhibition zone for Salmonella enterica serovar Typhi, E. coli, Streptococcus sp. and P. fluorescence ranged from 20 to 30 mm for 10 μL and 9–16 mm for 5μL treatments of mandarin peel EO. The differing concentrations of the citrus peel EOs between the studies might explain these contradictory results.

3.2. Orange Essential Oils

Over the past decade, several studies [24,37,53,54,55] have examined the antibacterial properties of sweet orange (Citrus sinensis) EO. A broad-spectrum antibacterial activity was observed against a range of foodborne pathogens, confirming its potential to be a natural antimicrobial agent for food preservation. In a study conducted by Guo et al. [37], the antimicrobial activity of cold-pressed and light phase EO extracted from orange peel was compared using E. coli, S. aureus, and B. subtilis. It was reported that light phase EO showed a better antimicrobial activity compared to the cold-pressed EO. The higher antimicrobial activity can be attributed to a higher quantity of carvone and limonene in the light phase EO. Nwachukwu et al. [56] tested the efficacy of orange peel EO extracted using water and ethanol (hot and cold) against E. coli, S. aureus, and Bacillus sp. It was noted that hot ethanol extracted EO was more effective than the water extracted EO at inhibiting the three bacteria strains. Hot ethanol might have facilitated the better release of volatile compounds present in orange peel EO. These findings are similar to those of Ali et al. [55], Bendaha et al. [52], and Kirbaslar et al. [57], who reported similar antimicrobial activity of orange (Citrus aurantim) peel EO against L. monocytogenes, S. aureus, E. coli, E. faecalis, B. cereus, K. pneumoniae and P. aeruginosa. One of the significant drawbacks of these studies [15,37,51,52,53,55,56,57] was that they fail to consider the MIC and MBC values, thus providing no foundation for EO application in food. However, Geraci et al. [24] and Tao et al. [54] had reported the MIC values of orange peel EO, and as anticipated Gram-positive (B. cereus, B. subtilis, S. aureus) bacteria were reported to be more susceptible to the orange peel EO compared to the Gram-negative (E. coli and P. aeruginosa) bacteria.

3.3. Grapefruit Essential Oils

The antimicrobial activity of grapefruit (Citrus paradisi) peel EO against B. subtilis, E. coli, S. aureus, S. enterica serovar Typhimurium and P. aeruginosa was reported by Deng et al. [23]. It was noted that Gram positive B. subtilis was the most sensitive amongst all strains investigated, while Gram negative P. aeruginosa was the least sensitive organism. This antibacterial activity may be attributed to the presence of abundant limonene in the grapefruit peel EO [44]. Similarly, pummelo (Citrus grandis) peel EO showed good inhibitory activity against Gram-positive bacteria (MIC- 9.38 µL/mL) and moderate activity against Gram-negative bacteria (MIC- 37.50 µL/mL) [40]. Terpene alcohols such as linalool are known for their inhibitory activity against Gram-negative bacteria [58]. Although a substantial amount of linalool was found in the pummelo peel EO, it did not inhibit E. coli [40]. This microorganism was only susceptible to pure linalool, but not to EO with linalool as one of the components in a mixture of compounds [59]. The use of EO instead of linalool alone might have contributed towards a higher MIC value of pummelo peel EO against E. coli.

3.4. Essential Oils from Other Fruit Peels

Several researchers have examined the antibacterial activity of various other fruit peels such as tamarillo [60], bergamot (Citrus bergamia) [57,61], sweet lemon (C. limetta) [53,62], C. deliciosa [63], kumquat (C. japonica) [64] and feijoa (Acca sellowiana) [65]. Surprisingly, Diep et al. [60] and Mandalari et al. [61] revealed that the tamarillo and bergamot peel flavonoids, respectively, exhibited strong antibacterial activity against Gram-negative bacteria such as E. coli, Pseudomonas putida, S. enterica serovar Typhimurium and P. aeruginosa, while Gram-positive bacteria (B. subtilis, L. innocua, S. aureus) were resistant. Similarly, El-Hawary et al. [63] found that C. deliciosa EO extracted from its leaves and peel was more effective against Gram-negative bacteria than the Gram-positive bacteria. In contrast, the inhibitions zones for bergamot peel EO (11mm to 16mm) with no clear distinction between Gram-positive and Gram-negative bacteria [57], and sweet lemon EO, demonstrated good antibacterial activity against both Gram-positive and Gram-negative bacteria with inhibition zones measuring between 10 to 35 mm [62].
Due to the difference in their cell wall structure [34], Gram-positive bacteria are more susceptible to EOs than Gram-negative bacteria [23,40,54,66]. However, published data have shown no clear differentiation between Gram-positive and Gram-negative bacteria [60,63]. The reason for this contradictory result is discussed in Section 4. It is somewhat surprising that many studies have assessed the antimicrobial activity by using only the agar disk/well diffusion method [15,22,39,50,51,52,53,55,56,60,63,65,67,68,69,70,71,72]. Agar disk/well diffusion is a quick typing tool used to determine the sensitivity of the bacterial strain. However, this quick typing tool cannot differentiate between bacteriostatic and bactericidal effects. The agar disk/well diffusion is a preliminary method that is not suitable to determine MIC or MBC, since it becomes quite challenging to measure the amount of EO diffused in the medium. Moreover, the hydrophobic nature of EO might pose an added challenge with regard to its ability to diffuse through the media, potentially resulting in uneven distribution. On the other hand, though tedious and time-consuming, broth macro dilution or microdilution methods allow quantifying the exact antimicrobial agent concentration that is effective against the pathogen and visibly distinguishes between bacteriostatic and bactericidal effects [49]. Most of the studies reviewed so far tend to overlook the importance of the broth dilution method for the determination of MIC and MBC of EOs, which is vital for determining the exact concentration required to kill bacteria, a prerequisite for assessing their potential application in food preservation.
Table 1. Overview of antimicrobial activities of fruit peel essential oils (EOs) and extracts.
Table 1. Overview of antimicrobial activities of fruit peel essential oils (EOs) and extracts.
Source of Peel EOTarget OrganismMethod UsedSolvent UsedTest ConcentrationRemarksReferences
TamarilloE. coli, P. aeruginosa, S. pyogenes, S. aureusDisk diffusionMilliQ, n-hexane, ethanol, methanol115 μL of 100 mg/mL on 13 mm diskE. coli was most sensitive to aqueous extract from the peel (inhibition zone of 24 mm), P. aeruginosa was most sensitive to methanol extract.[60]
GrapefruitB. subtilis, E. coli, S. aureus,
S. enterica serovar Typhimurium, P. aeruginosa
Disk diffusion, MIC determination-20 μL of 100, 50, 25, 12.5, 6.25, 3.125, 1.56, 0.78, 0.39 and 0.195 mg/mL of EO placed on each diskB. subtilis represented a maximum inhibitory zone of 35.59 mm and MIC value of 0.78 μL/mL. P. aeruginosa was least sensitive representing an inhibition zone of 8.57 mm and MIC value of 25.0 μL/mL[23]
Sweet orange, Lemon, BananaP. aeruginosa, K. pneumoniae, Serratia marcescens, E. coli,
P. vulgaris, S. enterica serovar Typhi, S. aureus, E. faecalis, L. monocytogenes, Aeromonas hydrophila, Streptococcus pyogenes, Lactobacillus casei
Agar well diffusion, MIC determinationDistilled water, Methanol, Ethanol,
Ethyl acetate
5 mg/mLK. pneumoniae was most susceptible to lemon peel extract (inhibition zone and MIC, 35 mm, and 130 μg/mL, respectively).[13]
KumquatE. coli, S. enterica serovar Typhimurium, S. aureus, P. aeruginosaDisk diffusion and MIC determination by broth microdilution methodMethanol 80%,
Ethanol 70%,
Ethyl acetate,
n- Hexane,
From 10 mg/mL, 25 μL of extract was placed on each disk.For all extracts, E. coli was most resistant (inhibition zone 11.3 mm and MIC of 679 μg/mL) while S. aureus was the most susceptible (inhibition zone 16.7 mm and MIC of 496 μg/mL) strain.[64]
Sweet orangeenterotoxigenic E. coli,
Lactobacillus sp
Disk diffusion and MIC determinationEO solutions prepared at 90% (v/v), using acetone7 μL of EO solution placed on each diskEO showed higher antimicrobial activity against ETEC, no activity shown against beneficial Lactobacillus sp.[22]
LemonB. subtilis, E. coli, S. enterica serovar Typhimurium, S. aureusDisk diffusion method-0.1 mL of EO solution placed on each diskRipened lemon peel EO was more effective against all four strains than the unripe lemon peel EO.[71]
Sweet orangeBacillus sp., E. coli, S. aureusAgar well diffusion methodHot ethanol,
Cold ethanol,
Hot aqueous,
Cold aqueous
50 and 100 μL of each extract placed on diskHot ethanolic extract (100 μL)
most effective, showing inhibitory zone of 16, 15 and 16 mm against Bacillus sp., E. coli and S. aureus, respectively.
FeijoaE. coli, S. aureusAgar well diffusion methodWater and Methanol extracts100 μL of each extract placed on diskMethanol extract was more effective (Inhibition zone for E. coli and S. aureus was 14.7 and 26.5 mm, respectively).[65]
Sweet orangeS. aureus, B. subtilis, E. coliMIC determination by tube dilution methodLight phase and cold-pressed EO-The MIC of light phase EO for S. aureus, B. subtilis and E. coli was 3.13, 1.56 and 0.78 μL/mL, respectively.[37]
Sweet orangeS. aureus, L. monocytogenes,
P. aeruginosa
MIC determination by agar dilution methodEO and hexane extracts100 to 2.5 mg/mLEO was effective against L. monocytogenes (MIC value of 15 mg/mL) but less active against S. aureus and P. aeruginosa. Hexane extract at 10 mg/mL concentration was most effective.[24]
Sweet orange, Lime, Mandarin, GrapefruitB. subtilis, S. aureus, E. faecalis, E. coli, P. aeruginosa,
N. gonorrhoeae
Disk diffusion and MIC determination by agar dilution method-10 μL of EO solution placed on each diskLime peel was most effective. MIC of 14 and 11 μL/mL was recorded for S. aureus and E. coli, respectively.[51]
Sour orange,
Sweet orange,
S. aureus, E. coli, E. faecalis,
B. cereus
Agar well diffusion methodAqueous extract50 μL of 100 mg/mL of extract was dispensed in each wellThe inhibition zones for S. aureus, E. faecalis, B. cereus and E. coli ranged from
10 to 18 mm, 9 to 17 mm, 11 to 18 mm, and 14 to 21 mm, respectively.
Bitter orangeL. monocytogenes,
S. aureus, E. coli DH5α, Citrobacter freundii
Disk diffusionHexane extract-S. aureus was moderately sensitive to bitter orange extract (inhibition zone of 10mm). The extract did not inhibit Gram-negative organisms.[52]
E. coli, P. aeruginosa, S. enterica subsp., S. aureus, E. faecalisDisk diffusion methodCold-pressed and water-distilled extracted EO100 μL of 10 and 20 mg/mL of EO was suspended in each well20mg/mL of pummelo peel EO presented antimicrobial activity against Gram negative Salmonella enterica subsp. followed by E. faecalis > E. coli > S. aureus > P. aeruginosa.[39]
Sweet orange, Sweet lemon, LemonS. enterica serovar Typhimurium, E. coliDisk diffusion methodHexane extract-The inhibitory zone for S. enterica serovar Typhimurium and E. coli ranged from 4 mm to 10 mm.[53]
PomegranateS. aureus, E. aerogenes, S. enterica serovar Typhimurium and K. pneumoniaeAgar well diffusion methodMethanol,
Ethanol (100, 70, 50, 30%),
10 μL of extract: water (1:6) was dispensed in each wellS. aureus was the most sensitive strain, followed by E. aerogenes, S. enterica serovar Typhimurium, K. pneumoniae. The inhibition zone for S. aureus ranged from 24.5 to 20.3 mm.[69]
BananaS. aureus, S. pyogenes,
Enterobacter aerogenes, K. pneumoniae, E. coli, Moraxella catarrhalis
Agar well diffusionAqueous extract-S. aureus showed an inhibition zone of 30 mm, but E. coli was resistant to the extract.[67]
C. deliciosaS. aureus, Micrococcus luteus,
E. coli, P. vulgaris
Agar diffusion method-15 μL of EO was dispensed on the agar surfaceThe inhibition zone for all tested organisms ranged from 8 mm to 30 mm.[63]
Sweet lemon
S. aureus, S. epidermidis,
S. agalactiae, E. faecalis,
Streptococcus pneumoniae,
S. pyogenes, E. coli, E. aerogenes, K. pneumoniae,
Proteus sp., S. enterica serovar Typhimurium,
Acinetobacter sp., Moraxella catarrhalis, P. aeruginosa
Agar well diffusion methodAqueous extract20 μL of extract was dispensed in each wellThe effect of lemon and sweet lemon peel on microbial isolates was not significantly different. The inhibition zone for lemon and sweet lemon ranged from 20–30 mm and 10–35 mm, respectively.[62]
GrapefruitB. cereus, S. faecalis, E. coli, K. pneumoniae, Pseudo- coccus sp., S. enterica serovar Typhimurium, Shigella flexneri, S. aureusAgar well diffusion methodMethanol, Ethanol100 μL of 8, 40 and 80 μg/mL concentrations of EO solutions were dispensed in each wellMethanol extract was more effective against all tested strains. B. cereus was the most sensitive bacteria (inhibition zone from 30.33 to 32.67 mm), while E. faecalis was the most resistant one (inhibition zone from 6.0 to 12.0 mm)[72]
PomegranateB. subtilis, S. aureus
E. coli, K. pneumoniae
Microdilution methodMethanolic and aqueous extracts0.097–12.5 mg/mLThe MIC value for the tested strains ranged from 0.2 to 0.78 mg/mL.[73]
PummeloS. aureus, B. subtilis, E. coliDisk diffusion and MIC determination by broth microdilution method-10 μL of 50% (v/v) EO was placed on each disk. MIC concentration ranged from 1.17 to 750 μL/mL (v/v).The inhibition zones for B. subtilis, S. aureus and E. coli were 17.08, 11.25 and 8.27 mm, respectively. The MIC values for B. subtilis, S. aureus and E. coli were 9.38, 9.38 and 37.50 μL/mL, respectively.[40]
Pomegranate16 strains of Salmonella sp.Disk diffusion and MIC determinationEthanol20 μL of 100, 200 and 500 μg/mL concentration of EO solution was placed on each disk. MIC concentration ranged from 3.9 to 2000 μg/mLThe inhibition zone and the MIC values for Salmonella sp. ranged from 13.3 to 18.8 mm and 62.5 to 1000 μg/mL, respectively.[74]
LemonP. aeruginosa, S. enterica serovar Typhimurium, and Micrococcus aureusAgar well diffusion method and MIC determinationMethanol,
Dilutions from crude extract were prepared as follows: 1:20, 1:40, 1:60, 1:80, 1:100All concentrations of lemon peel extracts effectively inhibited all the three strains tested.[75]
Mandarin, Tangerine, Sweet orange, Lime, GrapefruitE. coli, S. enterica serovar Typhi, K. pneumoniae, E. cloacae, P. fluorescence, Proteus myxofaciens, S. epidermidis, Streptococcus sp.Disk diffusion method-From 500 μg/mL of stock solution 5 and 10 μL of EO was placed on each disk.S. enterica serovar Typhi and P. myxofaciens were susceptible to all citrus EO tested.[15]
GrapefruitS. aureus, E. faecalis, S. epidermidis, E. coli, S. enterica serovar Typhimurium, S. marcescens and P. vulgarisDisk diffusion method-20 μL of extract was dispensed in each wellS. enterica serovar Typhimurium was the most resistant (15 mm) strain followed by E. faecalis (16 mm), S. epidermis (17 mm), S. marcescens (19 mm), P. vulgaris (21 mm) and S. aureus (53 mm).[38]
PomegranateE. coli, Pseudomonas fluorescens, S. enterica serovar Typhimurium, S. aureus, B. cereusMIC determination by tube dilution methodWater Final concentration of 0.01, 0.05, 0.1% was prepared in salineS. aureus and B. cereus got inhibited at a concentration of 0.01%, P. fluorescens at 0.1%, E. coli and S. enterica serovar Typhimurium were not inhibited.[76]
PomegranateL. monocytogenes, S. aureus
B. subtilis, E. coli, P. aeruginosa, K. pneumoniae,
Yersinia enterocolitica
Agar well diffusion and MIC determination by agar dilution methodMethanolic (80%) and water extracts800 μg/100 μL of extract was suspended in each well. MIC concentration ranged from 0 to 4 mg/mLThe inhibition zone for methanolic extract ranged from 13–20 mm. MIC determination showed that Y. enterocolitica was the most sensitive strain representing MIC of 0.25 mg/mL. [77]
Sour limeB. subtilis, B. cereus, S. aureus, E. coli, E. aerogenes S. enterica serovar TyphimuriumDisk diffusion method--B. subtilis, B. cereus, S. aureus, S. enterica serovar Typhimurium, E. coli and E. aerogenes showed inhibition zones of 22, 19.8, 18, 17, 16 and 10.5 mm, respectively.[68]
Sweet orangeS. aureus, B. subtilis, E. coliDisk diffusion and MIC determination by broth microdilution method-10 μL of 50% (v/v) EO was placed on each disk. MIC concentration ranged from 1.17 to 750 μL/mL (v/v).The inhibition zones for S. aureus, B. subtilis and E. coli were 23.37, 18.89 and 17.21 mm, respectively. The MIC values for S. aureus, B. subtilis and E. coli were 4.66, 9.33 and 18.75 μL/mL, respectively.[54]
Bitter orange,
Sweet orange,
S. aureus, B. cereus,
Mycobacterium smegmatis,
L. monocytogenes, M. luteus, E. coli, K. pneumoniae, P. aeruginosa, P. vulgaris
Disk diffusion method-20 μL of EO solution was placed on each diskLemon peel EO exhibited better antimicrobial activity towards all bacteria with inhibition zone ranging from 10 to 16 mm.[57]
BergamotE. coli, P. putida, S. enterica, L. innocua, B. subtilis, S. aureus, Lactococcus lactisMIC determined using Bioscreen CEthanol (70, 100%)200–1000 μg/mLThe MIC values for E. coli, S. enterica, P. putida were 200, 400, 500 μg/mL, respectively. Gram-positive bacteria showed no effect.[61]

4. Effect of Chemical Components of Essential Oils on Food Spoilage and Pathogenic Microbes

In the literature, various modes of antimicrobial activity of EOs against a range of bacteria have been discussed [5,7,78,79]. However, before investigating the effect of fruit peel EO on microbes, we should have a closer look at the cell-wall structure of Gram-negative and Gram-positive bacteria (Figure 2).
The hypothesis that Gram-positive bacteria are more susceptible to the effect of hydrophobic compounds such as EOs was first proposed by Plesiat et al. [80] followed by Nazzaro et al. [34], Chouhan et al. [79] and Raut et al. [81]. The difference between the susceptibility is attributable to the fact that Gram-positive bacteria have a thick layer of peptidoglycan linked to other hydrophobic molecules such as proteins and teichoic acid. This hydrophobic layer surrounding the Gram-positive bacterial cell may facilitate easy entry of hydrophobic molecules. On the other hand, Gram-negative bacteria have a more complex cell envelope comprising an outer membrane linked to the inner peptidoglycan layer via lipoproteins. The outer membrane contains proteins and lipopolysaccharides (lipid A), making it more resistant to the hydrophobic molecules in EO [82].
Other researchers investigating the antimicrobial activity of EOs showed no notable difference between the MIC values of Gram-positive and Gram-negative bacteria [13,39,60,61,64]. Although it has been hypothesized that the outer membrane is almost impermeable to the hydrophobic compounds, Plesiat et al. [80] argued that some hydrophobic compounds might cross the outer membrane via porin channels. Similarly, Van de Vel et al. [58] believe that some EO molecules are more active against Gram-positive bacteria, while others are active against Gram-negative bacteria, but the mechanisms remain unknown. Most studies on the antimicrobial activity of EOs have used E. coli and S. aureus as model microorganisms to represent Gram-negative and Gram-positive bacteria, respectively [65,83,84]. This could lead to a generalization of results, as not all Gram-negative and Gram-positive bacteria would follow a similar trend as observed in E. coli and S. aureus. Furthermore, the mode of action of EO depends on its chemical profile and the ratio of its active components [85]. The possible mechanisms wherein EOs interfere with bacterial proliferation may involve the following: (1) the disintegration of the bacterial outer membrane or phospholipid bilayer, (2) alteration of the fatty acid composition, (3) increase in membrane fluidity resulting in leakage of potassium ions and protons; (4) interference with glucose uptake, and (5) inhibition of enzyme activity or cell lysis (Figure 3) [5,86].
In general, fruit peel EOs may comprise more than a hundred compounds [43]. Major compounds can contribute around 85–95% of the total EO composition, while other minor compounds can be present in trace amounts. While these compounds may have specific antimicrobial effects, Cho et al.’s [86] review draws attention to the synergistic and additive effect minor compounds might have in combination with the other components. Terpenes and terpenoids are primary components of essential oil followed by polyphenols [32]. Here, we discuss the antimicrobial activity and mode of action of EOs and their components on the bacterial cell.

4.1. Terpenes and Terpenoids

Terpenes and terpenoids constitute a significant class of compounds in EOs known to have antimicrobial activity. The potential antimicrobial activity of thymol and carvacrol has been extensively discussed in previous reviews [7,34,79]; hence we exclude them from our discussion to focus on other EO compounds. Thymol and carvacrol are the major components of thyme and oregano oil, respectively, and are structurally analogous differing in the location of hydroxyl groups on the phenol ring [7].
It is well recognized that terpenes can disrupt the lipid assembly of the bacterial cell wall, leading to disintegration of the cell membrane, denaturation of cell proteins, leakage of cytoplasmic material, which ultimately causes cell lysis and cell death [47]. Kim et al. [87] were amongst the first to show the antimicrobial potential of EO components including citral, limonene, perillaldehyde, geraniol, linalool, α-terpineol, carvacrol, citronellal, eugenol, β-ionone and nerolidol against E. coli, S. enterica serovar Typhimurium, L. monocytogenes and Vibrio vulnificus. It was suggested that terpenes and terpenoids might interfere with oxidative phosphorylation or oxygen uptake in microbial cells, thereby inhibiting microbial growth [88]. Later, this hypothesis was supported by Zengin and Baysal’s study [89], wherein terpene compounds such as linalool, α-terpineol and eucalyptol were reported to damage the cell membrane and alter the morphological structure of S. aureus, S. enterica serovar Typhimurium and E. coli O157:H7. The plausible explanation for this observation was that these terpene compounds interacted with the membrane proteins and phospholipids, leading to cellular respiratory chain inhibition, interruption in oxidative phosphorylation, disruption of nucleic acid synthesis, and loss of metabolites [90].
Two studies conducted by Togashi et al. [90,91] examined the effect of geranylgeraniol, geraniol, nerolidol, linalool and farnesol on S. aureus. All these terpene alcohols were reported to have antibacterial activity, with farnesol and nerolidol demonstrating the most potent antibacterial activity as determined by the broth dilution technique. They also explored the mechanism of these terpene alcohols on the bacterial cell membrane by measuring the leakage of K+ ions from the bacterial cell, anticipating that distortion of the bacterial cell membrane leads to leakage of K+ ions, thus indicating the presence of membrane disrupting compounds. In support of this, Akiyama et al. [92] reported the strong inhibitory effect of farnesol against S. aureus. Farnesol has also exhibited notable antibacterial activity against biofilms of S. aureus and S. epidermidis [93,94]. Akiyama et al. [92] attributed these inhibitory effects of farnesol to its hydrophobic nature, which accumulates in the cell membrane, thus disrupting the cell membrane as illustrated by scanning electron microscopy (SEM). Furthermore, an ester compound of geranyl acetate makes it a more potent antimicrobial compound than its parent moiety (geraniol), purportedly due to its hydrophobicity [95]. However, past studies [31,96] have demonstrated the antimicrobial activity and mechanism of geraniol, rather than geranyl acetate. For instance, geraniol was noted to inhibit E. coli and S. aureus [97], and multidrug-resistant Enterobacter aerogenes by acting as an efflux pump inhibitor [96,98]. Similar, to farnesol, it is thought that the antimicrobial potential of geraniol was due to its hydrophobic nature.
Han et al. [44] and Liu et al. [99] examined the antibacterial mechanism of limonene on L. monocytogenes and the antibacterial mechanism of linalool on P. aeruginosa, respectively. In their analysis, Han et al. [44] and Liu et al. [99] demonstrated that the compounds distorted the cell wall structure of bacteria and led to leakage of intracellular molecules such as nucleic acids and proteins, which also affected the functionality of the respiratory chain complexes and hampered the process of adenosine triphosphate (ATP) synthesis. Moreover, Gao et al. [100] elaborated the anti-listeria activities of linalool against its planktonic cells and biofilms using RNA-sequence analysis. Other articles have discussed the antimicrobial efficacy of limonene [101] and linalool [102] against various strains of microorganisms. The antimicrobial activity of limonene is due to the presence of alkenyl substituent and a double bond in the molecular structure that enhances its antimicrobial activity [95]. Other authors proposed that the cell membrane may be an important site for linalool to inactivate the cell [100]. The interaction causes thickening of the Gram-positive cell wall, eventually leading to cell disruption [103]. The S (+) enantiomer of linalool enables it to interact with the negatively charged outer membrane of the Gram-negative cell, thus facilitating the easy entry of the compound into the intracellular space, leading to disruption [104].
Dorman et al. [105] tested 14 EO compounds against 25 strains of bacteria and reported that monoterpenoid and sesquiterpene demonstrate potent antimicrobial activity against most strains tested. In the same way, Trombetta et al. highlighted the antimicrobial potential of monoterpenes (linalyl acetate, thymol and menthol) against E. coli and S. aureus [106]. The hydroxyl group present in the compound may have contributed to its antimicrobial activity. Guimaraes et al. [31] evaluated 33 terpene compounds commonly isolated from EOs for their antimicrobial efficacy, of which only 16 compounds were reported to possess antibacterial activity. Scanning electron microscopy results revealed that individual components of EOs such as geraniol, citronellol, carveol, and terpineol altered the cellular morphology and destroyed the cell membrane. This is supported by two previous studies where similar compounds were found to be potent [105,106]. Lopez-Romero et al. [107] conducted a similar study wherein the antibacterial effect and mechanism of action of essential oil components such as carveol, carvone, citronellol, and citronellal were evaluated against E. coli and S. aureus. Citronellol was found to be the most effective, which led to a change in the cell membrane integrity, the surface charge followed by leakage of K+ ions. In another study, two pentacyclic triterpenes, namely α-amyrin and ursolic acid, were also reported to have a disorganizing effect on the E. coli cell membrane [108]. Additionally, Garcia et al. [66] listed five monoterpene compounds (citronellal, citral, α-pinene, isopullegol and L-carvone) which possessed antifungal properties against three fungal strains and suggested their potential use in tropical fruit preservation. Other researchers [109,110] have investigated the antimicrobial potential of a bicyclic sesquiterpene, i.e., β-caryophyllene, against a range of microorganisms. However, they were unable to explain for the antibacterial mechanism with their study.

4.2. Polyphenols

Studies on polyphenols extracted from various fruit sources are well represented in the literature, and it is acknowledged that polyphenols possess a range of antimicrobial activities against pathogenic microbes. For example, the polyphenols in the skin extracts of Italian red grape, plum and elderberries demonstrated strong inhibitory properties against S. aureus, B. cereus, E. coli, L. monocytogenes while showing a growth-promoting effect on beneficial microbes such as Lactobacillus rhamnosus, L paracasei and Lactobacillus plantarum [111].

4.2.1. Phenylpropenes

Although phenylpropenes account for a smaller proportion of total volatiles than terpenes and terpenoids, they have been noted to have a significant contribution to the antimicrobial activity of EOs [112]. Phenylpropenes are not only found in some fruit varieties such as apple peel [113], lemon peel [114] and grapefruit peel [115], but are also found in a wide variety of spices and herbs such as clove, star anise, sweet basil and fennel [116].
The antimicrobial potential of eugenol has been extensively investigated [117,118,119,120]. Eugenol is thought to alter the permeability of the cell membrane, followed by leakage of intracellular ATP and macromolecules such as protein and nucleic acids, ultimately leading to cell death [119]. This theory was supported by Cui et al.’s [118] study wherein eugenol permeabilized the cell membrane leading to leakage of intracellular macromolecules and enzymes such as β-galactosidase, ATP and alkaline phosphatase (AKP). Furthermore, Qian et al. [117] noted that eugenol demonstrates cell membrane permeability properties and presents potent inhibition against the biofilm formation of K. pneumoniae cells. Likewise, Ashrafudoulla et al. [119] reported antibiofilm activity against Vibrio parahaemolyticus and cell membrane damaging properties, which led to leakage of cell contents. Research by Nazzaro et al. found that isoeugenol worked in a similar way to eugenol [34]. Hyldgaard et al. [121] explained that isoeugenol formed hydrogen bonds with the lipid headgroup, thus disturbing the lipid structure and destabilizing the membrane. This mechanism of action is known as a “non-disruptive detergent-like mechanism”, and the free hydroxyl group and the molecule’s hydrophobic nature were considered accountable for their antimicrobial activity [122]. However, Gharib et al. [112] argued that hydrophobicity might not be the only factor contributing to the molecule’s antimicrobial activity, since in his study, eugenol and isoeugenol demonstrated a fluidizing effect on the bacterial cell wall. Furthermore, Auezova et al. [123] and Gharib et al. [112] examined the mechanism of allylic (eugenol and isoeugenol) and propenylic (estragole and anethole) phenylpropenes on the cell wall of E. coli and Staphylococcus epidermidis. They demonstrated the distinctive ability of estragole and anethole to penetrate the outer membrane of E. coli. The antimicrobial potency is conferred by the higher lipophilic nature of estragole and anethole (log P values of 3.5 and 3.4, respectively) in comparison to eugenol and isoeugenol (log P values of 2.5 and 3.0, respectively).
Cinnamaldehyde has also demonstrated anti-biofilm activities against S. epidermidis [124]. Other researchers have studied the antibacterial mechanism of cinnamaldehyde against E. coli, S. aureus [125] and Aeromonas hydrophila [126], reporting that it caused cell membrane distortion and leakage, in addition to condensation and polarization of the cytoplasmic content. The antibacterial activity of vanillin was studied against Mycobacterium smegmatis, and it was able to enhance the cell membrane permeability and alter cell membrane integrity [127].

4.2.2. Flavonoids

Flavonoids are polyphenolic compounds with a benzo-γ-pyrone group and are ubiquitously found in plant cells [36]. Few examples of flavonoids are flavanones, flavan-3,4-diols, chalcones, flavan-3-ols, flavonols, flavones, isoflavones, catechins, quercetin, anthocyanidins and proanthocyanidins [128]. Recent evidence suggests that flavonoids possess antibacterial activities against plant pathogens and human pathogens. Their antimicrobial mechanism is similar to traditional drugs [33], and hence could be of importance for use as natural antimicrobial agents.
A study on catechins showed that the compounds caused oxidative damage in E. coli and B. subtilis cells, thus altering cell membrane permeability and damaging the cell membrane [129]. Moreover, Cushnie et al. [130] also reported that catechins were responsible for potassium ion leakage in methicillin-resistant S. aureus (MRSA), which is the primary signal of membrane damage, and Tsuchiya et al. [131] reported that sophoraflavanone G significantly affected the membrane fluidity of the bacterial cells.

5. Application of Essential Oils in Food Products


Traditional food preservation methods include chilling, frozen storage, drying, salting, smoking and fermentation [132]. However, consumers have questioned techniques such as fermentation, brining, and salting, due to the increasing demand for reduced-salt foods [133]. The meat industries utilize chemical preservatives such as nitrate salt, sulfites, chlorides to inhibit the growth of foodborne pathogens. These compounds have been associated with carcinogenic effects and other health complications [133]. Hence, the options available to substitute chemical preservatives with natural compounds have attracted increased interest in recent years. Lucera et al. [134], in her review, outlined some natural preservatives of animal origin, (lactoferrin, lysozyme); bacteriocin from microbes (natamycin, nisin); natural polymers (chitosan); organic acids (citric and propionic acid); EOs and extracts derived from plants. In this context, EOs are attracting considerable attention due to their application as a natural bio-preservative and inhibitor in food matrices or food products. At present, the investigations have focused primarily on EOs from herbs and spices. There is limited research on fruit peel EOs. So, the discussion is widened here to cover the food applications of all plant-derived EOs. Some publications have investigated the potential contributions EOs/extracts to extend the shelf-life and to inhibit the growth of pathogens in fresh-cut vegetable mixtures [135], lettuce, purslane [136], fruit juices [137], ready to eat meat [138], chicken nuggets [76] and breast [139], minced beef [140,141] and turkey [142]. A literature review [141] published in 2018 included 2473 publications since 1990 on the antimicrobial activity of EOs. Many of these publications investigated the application of EO’s on food products, including 657 papers on fruits, 403 on vegetables, 415 on fish products, 410 on meat products, 216 on milk and dairy products, and 97 on bread and baked foods [143]. Other recent reviews have discussed the application of rosemary extract in meat [144], the synergistic effect of EO in seafood preservation [145], application of EO in active packaging [146] and as a food preservative [147]. The following section includes the recent history of EO by restricting the citations to the last 5–6 years to provide the readers with an update on EOs and their application in the food matrix (Table 2).
As consumers have gained greater awareness on issues related to health, processing and food additives, demand for natural and minimally processed food has soared. However, maintaining the freshness of fruits and fresh-cut vegetables for extended periods has been challenging. Spraying, dipping, coating, and impregnation are ways EOs can be applied to fruits and vegetables for maintaining shelf-life [134]. Some recent examples of these approaches are discussed here. He et al. [148] evaluated the effects of dipping cherry tomatoes in thyme EO nanoemulsion (TEON) against E. coli O157:H7 and the effect of TEON in combination with ultrasound treatment. Their study showed that TEON alone could effectively inhibit the growth of E. coli O157:H7 on the surface of cherry tomatoes, and there was a substantial synergistic effect of the combined treatment. Kang et al. [149] found that freshly cut red mustard leaves, when washed with cinnamon leaf EO nanoemulsion, reduced the count of E. coli, L. monocytogenes, S. enterica serovar Typhimurium by more than one log. Another study conducted by the same author showed that washing with cinnamon leaf EO nanoemulsion improved physical detachment and inhibited both L. monocytogenes and E. coli O157:H7 on kale leaves [150]. Both studies did not show any adverse changes in the quality attributes of mustard [149] and kale leaves [150]. The lettuce leaves examined during 7-day storage periods showed a reduction in E. coli O157:H7 population when rinsed with a combination of carvacrol/eugenol and thymol/eugenol when compared to the control (water rinse). However, the treatments had adverse effects on the sensory analyses [151]. In contrast, a combination of Spanish origanum oil and Spanish marjoram oil successfully inhibited L. monocytogenes from a mixture of fresh-cut vegetables without showing any adverse sensory attributes [135]. A recent study elucidated that Litsea cubeba EO added to bitter gourd, cucumber, carrot and spinach juices at MIC concentration decreased the counts of E. coli O157:H7 by 99.1%, 99.92%, 99.94%, 99.96%, respectively [152]. Krogsgård Nielsen et al. [153] tested the inhibitory potential of isoeugenol and encapsulated isoeugenol against L. monocytogenes, S. aureus, Leuconostoc mesenteroides, P. fluorescens in carrot juice. Contrary to expectations, their study did not find a significant difference in the inhibitory activity of encapsulated and non-encapsulated isoeugenol.
Besides fruits and vegetables, much work on the antimicrobial potential of EO was studied in meat products especially beef and beef products [154,155,156,157,158]. Pistachio EO [155] and Melaleuca alternifolia (tea tree) EO [157] reduced the total viable and total L. monocytogenes counts in ground beef. The efficiency of 5% and 10% clove EO on the inactivation of L. monocytogenes in ground beef at refrigeration (8 °C), chilling (0 °C) and freezing (18 °C) temperatures was investigated by Khaleque et al. [158]. They observed that 10% clove EO was a lethal concentration to inactivate L. monocytogenes irrespective of temperature conditions, but 5% clove EO was ineffective at inactivating the pathogen [158]. Similarly, Yoo et al. [154] found that 0.5%, 1.0% and 1.5% clove EO did not significantly reduce the count of E. coli O157:H7 and S. aureus in beef jerkies. However, their study took an additional step and demonstrated that the combined effect of clove EO with encapsulated atmospheric pressure plasma had a bactericidal effect on both pathogens. Likewise, a study conducted by Lin et al. [156] pointed out the synergistic effect of chrysanthemum EO incorporated into chitosan nanofibers which inhibited L. monocytogenes in beef at a rate of 99.9%.
A triple combination of thyme/cinnamon/clove EO in the food matrix was first applied experimentally by Chaichi et al. [159]. The triple combination at FIC of 0.3, had a bacteriostatic effect on P. fluorescens inoculated in chicken breast meat, while a triple combination at higher concentration (200 mg/kg) had an instant bactericidal effect. Thyme EO effectively inhibited P. aeruginosa, E. coli and S. enterica serovar Typhimurium in ground beef [160]. A recent study by Kazemeini et al. [161] prepared edible coatings of alginate containing Trachyspermum ammi EO (TAEO) as nanoemulsion to control the growth of L. monocytogenes in turkey fillets. The turkey fillets were coated with the emulsion and stored at 4 °C for 12 days. They observed the highest reduction of L. monocytogenes numbers in turkey fillets treated with 3% alginate containing 0.5% and 1% TAEO compared to non-coated samples. Other research articles have reported that EO nano emulsions effectively inhibited pathogens in rainbow trout fillet [162] and chicken breast fillets [163]. Apart from fruits, vegetables and meat products, the application of EO has also been evaluated on bakery [164,165] and dairy products [166].
Although several authors [152,157,165,166] have claimed successful testing for the application of EOs in different food systems, their approach has not escaped criticism. Santos et al. [167] emphasized the use of MBC concentration rather than MIC concentration in the food matrix to ensure a complete inhibition. These authors [167] questioned the usefulness of EOs in food systems because various factors such as environmental condition, age and cultivar of the plant, time harvested, extract composition and extraction method may impact the antimicrobial activity of the EO. All the above factors might challenge the rationale of applying EOs at a commercial level. Moreover, it is known that fat and protein present in food can solubilize or bind to phenolic compounds in EO, thus reducing its antimicrobial efficacy [157]. This view was supported by Khaleque et al. [158], who analyzed the effect of cinnamon EO at a higher concentration (2.5 and 5.0%) against L. monocytogenes in ground beef and found that cinnamon EO was unsuccessful in inactivating L. monocytogenes in ground beef. They also reported adverse organoleptic impacts upon using higher concentrations of EOs. In a study by Lages et al. [168], thyme EO combined with beet juice powder failed to give a desirable effect in reducing coagulase-positive Staphylococcus in meat sausage. It was recommended that combining half of the suggested dosage of chemical preservatives such as nitrites with EO could be feasible. Despite the question regarding the suitability of EO in minimally processed food products [167], only a few studies did not show effective inhibition by EOs of foodborne pathogens. In contrast, many studies have demonstrated the successful replacement of synthetic preservatives with EO in different food systems [165,166,169]. Since Santos et al. [167] did not use EOs in minimally processed food products, their assumptions need further validation. Their paper would have been more convincing if the authors had used food matrices to prove their hypothesis. There is evidence that EOs exhibit antimicrobial properties, therefore, their ability to be used as a natural preservative on an industrial scale needs further rigorous evaluation.
Table 2. Overview of recent studies on antimicrobial activity of different essential oils (EOs) in the food matrix.
Table 2. Overview of recent studies on antimicrobial activity of different essential oils (EOs) in the food matrix.
Essential OilPathogenFood Method UsedConcentration AppliedReferences
Thyme (Thymus vulgaris) E. coli O157:H7Cherry tomatoesDipping0.0625, 0.125 mg/mL[148]
Clove (Syzygium aromaticum)E. coli O157:H7, S. aureusBeef jerkiesTreated with EO and dried for 2 hrs0.50%, 1.00%, 1.50%[154]
Ajwain (Trachyspermum ammi)L. monocytogenesTurkey filletsCoating8, 4, 2 mg/mL[161]
May chang (Litsea cubeba)E. coli O157:H7Bitter gourd, cucumber, carrot, and spinach juiceInoculation0.5, 0.25 mg/mL[152]
Felon herb (Artemisia persica
L. monocytogenes, E. coli O157:H7Probiotic dooghAddition of EO and mixing75 ppm, 150 ppm[164]
Rosemary (Rosmarinus officinalis), Lavender (Lavandula), Mint (Mentha piperita)Penicillium crustosumBreadExposing bread to a disk loaded with EO 125, 250, 500 µL/L[165]
Thyme (Thy), Cinnamon (CN) (Cinnamomum verum), Clove (CV)P. fluorescensChicken breast Coated by dipping in EO emulsion for 5 minThy- 0.560 g/L, CN- 0.042, 0.170 g/L, CV- 0.078, 0.312 g/L[159]
Ginger (Zingiber officinale), Clove, ThymeS. aureus, P. aeruginosa, E. coli, E. faecalis,
P. fluorescens, C. albicans and Aspergillus parasiticus
Fortified cheeseEO added and stirred0.01%[166]
Tea tree (Melaleuca alternifolia)TVC, Psychrophilic, Coliform, Salmonella, Yeast, and mould countBeef steaksAddition of EO and mixing0.1%, 0.5%[155]
Cranberry extract (Vaccinium macrocarpon)Listeria sp.Chicken breastDipped in extract solution4, 8 mg/mL[170]
ThymeThermotolerant coliforms and Escherichia coli HamburgerAddition of EO and mixing0.1 g/100 g of thyme EO
1 g/100 g of encapsulated thyme EO
Cinnamon leaf EO nanoemulsionL. monocytogenes, E. coli O157:H7Kale leavesWashing50 ppm[150]
Thymol, Eugenol, CarvacrolE. coli O157:H7Lettuce leavesRinsing0.63 mg/mL[151]
Chrysanthemum (Chrysanthemum indicum)L. monocytogenesBeef Packed into membrane (Chitosan nanofiber loaded with EO) 1.5%[156]
Pistachio (Pistacia vera)Total viable count (TVC)Ground beefEO added to meat and stomached for 1 min1.5% (v/w)[157]
Black cumin (Bunium persicum)E. coli O157:H7Rainbow trout filletCoated by dipping in nanoemulsion for 15 min0.5%[162]
Cranberry extract (Vaccinium macrocarpon)Aerobic mesophilic count, Brochothrix thermosphacta, P. putida, L. mesenteroides, L. monocytogenes, C. jejuniPork meat slurry, hamburger, cooked hamMixed in meat3.3%, 1.65%, 0.83%, 0.42%[171]
Anise (Pimpinella anisum)TVC,
Psychotropic count,
Lactic acid bacteria,
Pseudomonas sp.
Minced beefEO added using micropipette and massaged manually for 2min0.1%, 0.3%, 0.5% (v/w)[172]
Coriander (Coriandrum sativum)TVC, sulphite-reducing clostridia, Salmonella sp., E. coli, L. monocytogenesPork sausageMixed in sausage0.000, 0.075, 0.100, 0.125, 0.150 μL/g[173]
CinnamonTVC, EnterobacteriaceaeItalian pork sausageMixed in sausage0.1%, 0.5% (v/m)[174]
Ginger Psychrophilic, Yeast and mould countChicken breast filletCoated by dipping in emulsion3%, 6%[163]
Cranberry extract E. coli,
Salmonella enterica serovar Enteritidis, L. monocytogenes, S. aureus
Minced pork 2.5 g/100 g[175]
ThymeE. coli, S. enterica serovar Typhimurium, S. aureus, and P. aeruginosaMinced beef meatEO added to meat and stomached for 5 min0.001%, 0.05%, 3% of EO in 10% DMSO (v/w)[160]
Cinnamon EO (CEO) and grape seed extract (GSE)TVC, Lactic acid bacteria, Psychotropic count, Yeast, and mould countSausageMixed in sausage and packed in polyamide bagsCEO (0.02% and 0.04%) and GSE (0.08% and 0.16%)[176]
Apple mint (Mentha suaveolens)E. coli, S. aureusTurkey sausage 2, 5, 10 mg/g[177]
IsoeugenolL. monocytogenes, S. aureus, Leuconostoc mesenteroides, P. fluorescensCarrot juiceInoculation702, 1580 mg/mL[153]
ThymeSalmonella enterica serovar Enteritidis,
S. enterica serovar Typhimurium,
S. Montevideo and
S. Infantis
Minced porkMixed in minced meat and vacuum packed 0.3%, 0.6%, 0.9%[178]
ThymeL. monocytogenesBeef and pork sausage Mixed and vacuum packed100 ppm[179]
Clove, CinnamonL. monocytogenesGround beefAdding and mixingClove—5%, 10%
Cinnamon—2.5%, 5%
origanum oil, Spanish marjoram oil and coriander oil
L. monocytogenesFresh cut vegetablesImmersing in EO solution0.1%, 0.4%, 0.9%[135]
Peppermint (Mentha piperita)Vibrio spp. CheeseApplying on surface5–15 µL/mL[180]

6. Food Regulations on Applications of Essential Oils

The European Commission has documented a variety of EO compounds as approved flavour additives in different types of food products. In 2008, the European Commission released a list of approved compounds which is updated regularly. Some of the registered flavoring compounds that pose no risk to human health are limonene, linalool, β-caryophyllene, pinene, thymol, carvacrol, carvone, eugenol, isoeugenol, vanillin, citral, citronellal, cinnamaldehyde, menthol and lavandulol [181]. Moreover, the Food and Drug Administration (FDA) of the United States also recognizes these compounds as GRAS. Crude EOs such as mustard, oregano, clove, cinnamon, nutmeg, thyme, basil, rosemary and lavender are recognized as GRAS. The regulatory limits on acceptable daily intake on EO compounds and EOs are in place to govern their use in food products [7]. Despite the regulatory limits, EOs might cause allergic reactions and ingesting high doses of EOs or topical applications of EOs for a long period have been associated with severe health problems, such as oral toxicity and dermatitis [182]. Therefore, it is crucial to attain a fine balance between toxicity and effective dose in food products.

7. Conclusions and Future Prospects

Evidence from in vitro and in situ studies suggests that EOs possess good antibacterial activity against a wide range of foodborne pathogens. This review has evaluated studies on EOs that have the potential to act as natural preservatives in food products, due to their antioxidant and antimicrobial properties [183,184]. The potential of all plant-derived EOs, not just fruit peel EOs, has been evaluated for use as a preservative in foods. However, their application in food products have been restricted at an industrial scale as high doses are required to attain good antimicrobial activity, and the quantity, source and active composition profile of the EO to be used in food has not been optimized. In addition, components of the foods, such as fat [185], starch [186] and protein [187], may bind to the active compounds in EOs and reduce their efficacy. The volatile compounds in EOs may also produce undesirable chemical compounds by interacting with other food components such as proteins. To validate the use of EOs at an industrial level, the evaluation of these aspects is of paramount importance.
Firstly, high concentrations of EO in food have shown unappealing sensory attributes. However, this problem may be addressed by evaluating an effective synergistic/additive combination of EOs or a combination of EOs with other food preservation techniques such as temperature, irradiation, and pulse-electric field to reduce the required dosage of EO for the inhibition of pathogens. Another plausible solution for minimizing the interaction of EO compounds with food components such as fat, starch and proteins is by encapsulating the EO in an appropriate biodegradable material (e.g., chitosan), which might ensure controlled release without altering its biological activity. Secondly, a detailed understanding of how EOs work (the mechanism of action) will provide insights into the application of EO in the food industry to combat the proliferation of food-borne pathogens. To further study the mechanism of action, proteomic and transcriptomic analyses are needed to understand the pathways targeted by the EO compounds. The transition of in vitro experiments to in vivo trials to evaluate the efficacy of EOs has always posed an added challenge. Another future opportunity lies in the potential effects of EOs on immunity and gut health. Recent research reported that a combination of oregano extract with peppermint and thyme EO supported the growth of probiotic bacteria and positively affected the gut’s microbial composition [188]. Further research regarding the role of EO on the gut microbiome would be worth exploring.

Author Contributions

Conceptualization, M.A., S.S. and S.Y.Q.; writing—original draft preparation, M.A.; writing—review and editing, M.A., S.S., K.H., C.A.B., S.Y.Q.; supervision, S.S., K.H., S.Y.Q.; project administration, S.Y.Q.; funding acquisition, S.S., S.Y.Q. All authors have read and agreed to the published version of the manuscript.


This research is partially funded by The University of Auckland (Press Account Number- 9448-UOA-MANG207) and Food and Health Programme Seed Grant (4200-UOA-48422-A8AN).

Informed Consent Statement

Not applicable.


The authors would like to thank The University of Auckland for the Doctoral Scholarship awarded to the first author and Food and Health Programme Seed Grant.

Conflicts of Interest

The authors declare no conflict of interest.


  1. Singh, B.; Singh, J.P.; Kaur, A.; Singh, N. Antimicrobial potential of pomegranate peel: A review. Int. J. Food Sci. Technol. 2019, 54, 959–965. [Google Scholar] [CrossRef]
  2. Asbahani, A.E.; Miladi, K.; Badri, W.; Sala, M.; Addi, E.H.A.; Casabianca, H.; Mousadik, A.E.; Hartmann, D.; Jilale, A.; Renaud, F.N.R.; et al. Essential oils: From extraction to encapsulation. Int. J. Pharm. 2015, 483, 220–243. [Google Scholar] [CrossRef]
  3. Rios, J.L. Essential Oils: What They Are and How the Terms Are Used and Defined. In Essential Oils in Food Preservation, Flavor and Safety; Preedy, V.R., Ed.; Academic Press: San Diego, CA, USA, 2016; Chapter 1; pp. 3–10. [Google Scholar]
  4. Martucci, J.F.; Gende, L.B.; Neira, L.M.; Ruseckaite, R.A. Oregano and lavender essential oils as antioxidant and antimicrobial additives of biogenic gelatin films. Ind. Crop. Prod. 2015, 71, 205–213. [Google Scholar] [CrossRef]
  5. Burt, S. Essential oils: Their antibacterial properties and potential applications in foods—A review. Int. J. Food Microbiol. 2004, 94, 223–253. [Google Scholar] [CrossRef] [PubMed]
  6. Garzoli, S.; Petralito, S.; Ovidi, E.; Turchetti, G.; Laghezza Masci, V.; Tiezzi, A.; Trilli, J.; Cesa, S.; Casadei, M.A.; Giacomello, P.; et al. Lavandula × intermedia essential oil and hydrolate: Evaluation of chemical composition and antibacterial activity before and after formulation in nanoemulsion. Ind. Crop. Prod. 2020, 145, 112068. [Google Scholar] [CrossRef]
  7. Hyldgaard, M.; Mygind, T.; Meyer, R.L. Essential oils in food preservation: Mode of action, synergies, and interactions with food matrix components. Front. Microbiol. 2012, 3, 12. [Google Scholar] [CrossRef] [Green Version]
  8. Calo, J.R.; Crandall, P.G.; O’Bryan, C.A.; Ricke, S.C. Essential oils as antimicrobials in food systems—A review. Food Control 2015, 54, 111–119. [Google Scholar] [CrossRef]
  9. Aleksic Sabo, V.; Knezevic, P. Antimicrobial activity of Eucalyptus camaldulensis Dehn. plant extracts and essential oils: A review. Ind. Crop. Prod. 2019, 132, 413–429. [Google Scholar] [CrossRef]
  10. Papadochristopoulos, A.; Kerry, J.P.; Fegan, N.; Burgess, C.M.; Duffy, G. Natural anti-microbials for enhanced microbial safety and shelf-life of processed packaged meat. Foods 2021, 10, 1598. [Google Scholar] [CrossRef]
  11. Joshi, V.; Kumar, A.; Kumar, V. Antimicrobial, antioxidant and phyto-chemicals from fruit and vegetable wastes: A review. Int. J. Food Ferment. Technol. 2012, 2, 123–136. [Google Scholar]
  12. Chanda, S.; Barvaliya, Y.; Kaneria, M.; Rakholiya, K. Fruit and vegetable peels—Strong natural source of antimicrobics. In Current Research, Technology and Education Topics in Apllied Microbiology and Microbial Biotechnology; Mendez, V.A., Ed.; Formatex Research Center: Badajoz, Spain, 2010; Volume 1, pp. 444–450. [Google Scholar]
  13. Saleem, M.; Saeed, M.T. Potential application of waste fruit peels (orange, yellow lemon and banana) as wide range natural antimicrobial agent. J. King Saud Univ. Sci. 2020, 32, 805–810. [Google Scholar] [CrossRef]
  14. Ayala-Zavala, J.F.; Rosas-Domínguez, C.; Vega-Vega, V.; González-Aguilar, G.A. Antioxidant enrichment and antimicrobial protection of fresh-cut fruits using their own byproducts: Looking for integral exploitation. J. Food Sci. 2010, 75, R175–R181. [Google Scholar] [CrossRef] [PubMed]
  15. Javed, S.; Mahmood, Z.; Shoaib, A.; Javaid, D.A. Biocidal activity of citrus peel essential oils against some food spoilage bacteria. J. Med. Plants Res. 2011, 5, 2868–2872. [Google Scholar]
  16. Alsaraf, S.; Hadi, Z.; Al-Lawati, W.M.; Al Lawati, A.A.; Khan, S.A. Chemical composition, in vitro antibacterial and antioxidant potential of Omani Thyme essential oil along with in silico studies of its major constituent. J. King Saud Univ. Sci. 2020, 32, 1021–1028. [Google Scholar] [CrossRef]
  17. Smigielski, K.; Prusinowska, R.; Stobiecka, A.; Kunicka-Styczyñska, A.; Gruska, R. Biological Properties and Chemical Composition of Essential Oils from Flowers and Aerial Parts of Lavender (Lavandula angustifolia). J. Essent. Oil Bear. Plants 2018, 21, 1303–1314. [Google Scholar] [CrossRef]
  18. Purkait, S.; Bhattacharya, A.; Bag, A.; Chattopadhyay, R.R. Synergistic antibacterial, antifungal and antioxidant efficacy of cinnamon and clove essential oils in combination. Arch. Microbiol. 2020, 202, 1439–1448. [Google Scholar] [CrossRef]
  19. Meng, F.C.; Zhou, Y.-Q.; Ren, D.; Wang, R.; Wang, C.; Lin, L.G.; Zhang, X.Q.; Ye, W.-C.; Zhang, Q.W. Turmeric: A Review of Its Chemical Composition, Quality Control, Bioactivity, and Pharmaceutical Application. In Natural and Artificial Flavoring Agents and Food Dyes; Grumezescu, A.M., Holban, A.M., Eds.; Academic Press: Cambridge, MA, USA, 2018; Chapter 10; pp. 299–350. [Google Scholar]
  20. Bakkali, F.; Averbeck, S.; Averbeck, D.; Idaomar, M. Biological effects of essential oils—A review. Food Chem. Toxicol. 2008, 46, 446–475. [Google Scholar] [CrossRef]
  21. Ju, J.; Xie, Y.; Guo, Y.; Cheng, Y.; Qian, H.; Yao, W. The inhibitory effect of plant essential oils on foodborne pathogenic bacteria in food. Crit. Rev. Food Sci. Nutr. 2019, 59, 3281–3292. [Google Scholar] [CrossRef] [PubMed]
  22. Ambrosio, C.M.S.; Ikeda, N.Y.; Miano, A.C.; Saldaña, E.; Moreno, A.M.; Stashenko, E.; Contreras-Castillo, C.J.; Da Gloria, E.M. Unraveling the selective antibacterial activity and chemical composition of citrus essential oils. Sci. Rep. 2019, 9, 17719. [Google Scholar] [CrossRef] [Green Version]
  23. Deng, W.; Liu, K.; Cao, S.; Sun, J.; Zhong, B.; Chun, J. Chemical Composition, Antimicrobial, Antioxidant, and Antiproliferative Properties of Grapefruit Essential Oil Prepared by Molecular Distillation. Molecules 2020, 25, 217. [Google Scholar] [CrossRef] [Green Version]
  24. Geraci, A.; Di Stefano, V.; Di Martino, E.; Schillaci, D.; Schicchi, R. Essential oil components of orange peels and antimicrobial activity. Nat. Prod. Res. 2017, 31, 653–659. [Google Scholar] [CrossRef]
  25. Lockwood, G.B. Techniques for gas chromatography of volatile terpenoids from a range of matrices. J. Chromatogr. A 2001, 936, 23–31. [Google Scholar] [CrossRef]
  26. Tranchida, P.Q.; Bonaccorsi, I.; Dugo, P.; Mondello, L.; Dugo, G. Analysis of Citrus essential oils: State of the art and future perspectives. A review. Flavour Fragr. J. 2012, 27, 98–123. [Google Scholar] [CrossRef]
  27. Turek, C.; Stintzing, F.C. Impact of different storage conditions on the quality of selected essential oils. Food Res. Int. 2012, 46, 341–353. [Google Scholar] [CrossRef]
  28. Turek, C.; Stintzing, F.C. Stability of Essential Oils: A Review. Compr. Rev. Food Sci. Food Saf. 2013, 12, 40–53. [Google Scholar] [CrossRef]
  29. Dhifi, W.; Bellili, S.; Jazi, S.; Bahloul, N.; Mnif, W. Essential Oils’ Chemical Characterization and Investigation of Some Biological Activities: A Critical Review. Medicines 2016, 3, 25. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  30. Tongnuanchan, P.; Benjakul, S. Essential Oils: Extraction, Bioactivities, and Their Uses for Food Preservation. J. Food Sci. 2014, 79, R1231–R1249. [Google Scholar] [CrossRef]
  31. Guimaraes, A.; Meireles, L.; Lemos, M.; Guimaraes, M.; Endringer, D.; Fronza, M.; Scherer, R. Antibacterial Activity of Terpenes and Terpenoids Present in Essential Oils. Molecules 2019, 24, 2471. [Google Scholar] [CrossRef] [Green Version]
  32. Lyu, X.; Lee, J.; Chen, W.N. Potential Natural Food Preservatives and Their Sustainable Production in Yeast: Terpenoids and Polyphenols. J. Agric. Food Chem. 2019, 67, 4397–4417. [Google Scholar] [CrossRef]
  33. Cutrim, C.S.; Cortez, M.A.S. A review on polyphenols: Classification, beneficial effects and their application in dairy products. Int. J. Dairy Technol. 2018, 71, 564–578. [Google Scholar] [CrossRef]
  34. Nazzaro, F.; Fratianni, F.; De Martino, L.; Coppola, R.; De Feo, V. Effect of essential oils on pathogenic bacteria. Pharmaceuticals 2013, 6, 1451–1474. [Google Scholar] [CrossRef] [PubMed]
  35. Gorniak, I.; Bartoszewski, R.; Kroliczewski, J. Comprehensive review of antimicrobial activities of plant flavonoids. Phytochem. Rev. 2019, 18, 241–272. [Google Scholar] [CrossRef] [Green Version]
  36. Kumar, S.; Pandey, A.K. Chemistry and Biological Activities of Flavonoids: An Overview. Sci. World J. 2013, 2013, 162750. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  37. Guo, Q.; Liu, K.; Deng, W.; Zhong, B.; Yang, W.; Chun, J. Chemical composition and antimicrobial activity of Gannan navel orange (Citrus sinensis Osbeck cv. Newhall) peel essential oils. Food Sci. Nutr. 2018, 6, 1431–1437. [Google Scholar] [CrossRef] [PubMed]
  38. Uysal, B.; Sozmen, F.; Aktas, O.; Oksal, B.S.; Kose, E.O. Essential oil composition and antibacterial activity of the grapefruit (Citrus Paradisi. L) peel essential oils obtained by solvent-free microwave extraction: Comparison with hydrodistillation. Int. J. Food Sci. Technol. 2011, 46, 1455–1461. [Google Scholar] [CrossRef]
  39. Ou, M.C.; Liu, Y.H.; Sun, Y.W.; Chan, C.F. The Composition, Antioxidant and Antibacterial Activities of Cold-Pressed and Distilled Essential Oils of Citrus paradisi and Citrus grandis (L.) Osbeck. Evid.-Based Complement. Altern. Med. 2015, 2015, 804091. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  40. Tao, N.G.; Liu, Y.J. Chemical Composition and Antimicrobial Activity of the Essential Oil from the Peel of Shatian Pummelo (Citrus Grandis Osbeck). Int. J. Food Prop. 2012, 15, 709–716. [Google Scholar] [CrossRef]
  41. Hosni, K.; Zahed, N.; Chrif, R.; Abid, I.; Medfei, W.; Kallel, M.; Brahim, N.B.; Sebei, H. Composition of peel essential oils from four selected Tunisian Citrus species: Evidence for the genotypic influence. Food Chem. 2010, 123, 1098–1104. [Google Scholar] [CrossRef]
  42. Hou, H.S.; Bonku, E.M.; Zhai, R.; Zeng, R.; Hou, Y.L.; Yang, Z.H.; Quan, C. Extraction of essential oil from Citrus reticulate Blanco peel and its antibacterial activity against Cutibacterium acnes (formerly Propionibacterium acnes). Heliyon 2019, 5, e02947. [Google Scholar] [CrossRef] [Green Version]
  43. Peng, Y.; Bishop, K.S.; Quek, S.Y. Compositional analysis and aroma evaluation of Feijoa essential oils from New Zealand grown cultivars. Molecules 2019, 24, 2053. [Google Scholar] [CrossRef] [Green Version]
  44. Han, Y.; Sun, Z.; Chen, W. Antimicrobial susceptibility and antibacterial mechanism of limonene against Listeria monocytogenes. Molecules 2020, 25, 33. [Google Scholar] [CrossRef] [Green Version]
  45. Fancello, F.; Petretto, G.L.; Zara, S.; Sanna, M.L.; Addis, R.; Maldini, M.; Foddai, M.; Rourke, J.P.; Chessa, M.; Pintore, G. Chemical characterization, antioxidant capacity and antimicrobial activity against food related microorganisms of Citrus limon var. pompia leaf essential oil. LWT Food Sci. Technol. 2016, 69, 579–585. [Google Scholar] [CrossRef]
  46. Swamy, M.K.; Akhtar, M.S.; Sinniah, U.R. Antimicrobial properties of plant essential oils against human pathogens and their mode of action: An updated review. Evid.-Based Complement. Altern. Med. 2016, 2016, 3012462. [Google Scholar] [CrossRef] [PubMed]
  47. Fisher, K.; Phillips, C. Potential antimicrobial uses of essential oils in food: Is citrus the answer? Trends Food Sci. Technol. 2008, 19, 156–164. [Google Scholar] [CrossRef]
  48. Wiegand, I.; Hilpert, K.; Hancock, R. Agar and broth dilution methods to determine the minimal inhibitory concentration (MIC) of antimicrobial substance. Nat. Protoc. 2008, 3, 163–175. [Google Scholar] [CrossRef] [PubMed]
  49. Balouiri, M.; Sadiki, M.; Ibnsouda, S.K. Methods for in vitro evaluating antimicrobial activity: A review. J. Pharm. Anal. 2016, 6, 71–79. [Google Scholar] [CrossRef] [Green Version]
  50. Al-Fekaiki, D.; Niamah, A.; Al-Sahlany, S. Extraction and identification of essential oil from Cinnamomum Zeylanicum barks and study the antibacterial activity. J. Microbiol. Biotechnol. Food Sci. 2017, 7, 312–316. [Google Scholar] [CrossRef]
  51. Abd-Elwahab, S.M.; El-Tanbouly, N.D.; Moussa, M.Y.; Abdel-Monem, A.R.; Fayek, N.M. Antimicrobial and Antiradical Potential of Four Agro-waste Citrus Peels Cultivars. J. Essent. Oil-Bear. Plants 2016, 19, 1932–1942. [Google Scholar] [CrossRef]
  52. Bendaha, H.; Bouchal, B.; El Mounsi, I.; Salhi, A.; Berrabeh, M.; El Bellaoui, M.; Mimouni, M. Chemical composition, antioxidant, antibacterial and antifungal activities of peel essential oils of citrus aurantium grown in Eastern Morocco. Der Pharm. Lett. 2016, 8, 239–245. [Google Scholar]
  53. Gupta, M.; Gularia, P.; Singh, D.; Gupta, S. Analysis of aroma active constituents, antioxidant and antimicrobial activity of C. Sinensis, Citrus limetta and C. Limon fruit peel oil by GC-MS. Biosci. Biotechnol. Res. Asia 2014, 11, 895–899. [Google Scholar] [CrossRef] [Green Version]
  54. Tao, N.G.; Liu, Y.J.; Zhang, M.L. Chemical composition and antimicrobial activities of essential oil from the peel of bingtang sweet orange (Citrus sinensis Osbeck). Int. J. Food Sci. Technol. 2009, 44, 1281–1285. [Google Scholar] [CrossRef]
  55. Ali, J.; Abbas, S.; Khan, F.A.; Rehman, S.U.; Shah, J.; Rahman, Z.U.; Rahman, I.U.; Paracha, G.M.U.; Khan, M.A.; Shahid, M. Biochemical and antimicrobial properties of Citrus peel waste. Pharmacologyonline 2016, 3, 98–103. [Google Scholar]
  56. Nwachukwu, B.C.; Taiwo, M.O.; Olisemeke, J.K.; Obero, O.J.; Abibu, W.A. Qualitative Properties and Antibacterial Activity of Essential Oil obtained from Citrus sinensis Peel on Three Selected Bacteria. Biomed. J. Sci. Tech. Res. 2019, 19. [Google Scholar] [CrossRef]
  57. Kirbaslar, G.F.; Tavman, A.; Dulger, B.; Turker, G. Antimicrobial activity of Turkish Citrus peel oils. Pak. J. Bot. 2009, 41, 3207–3212. [Google Scholar]
  58. Van de Vel, E.; Sampers, I.; Raes, K. A review on influencing factors on the minimum inhibitory concentration of essential oils. Crit. Rev. Food Sci. Nutr. 2019, 59, 357–378. [Google Scholar] [CrossRef]
  59. Faleiro, M.L.; Miguel, M.G.; Ladeiro, F.; Venâncio, F.; Tavares, R.; Brito, J.C.; Figueiredo, A.C.; Barroso, J.G.; Pedro, L.G. Antimicrobial activity of essential oils isolated from Portuguese endemic species of Thymus. Lett. Appl. Microbiol. 2003, 36, 35–40. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  60. Diep, T.T.; Yoo, M.J.Y.; Pook, C.; Sadooghy-Saraby, S.; Gite, A.; Rush, E. Volatile Components and Preliminary Antibacterial Activity of Tamarillo (Solanum betaceum Cav.). Foods 2021, 10, 2212. [Google Scholar] [CrossRef] [PubMed]
  61. Mandalari, G.; Bennett, R.N.; Bisignano, G.; Trombetta, D.; Saija, A.; Faulds, C.B.; Gasson, M.J.; Narbad, A. Antimicrobial activity of flavonoids extracted from bergamot (Citrus bergamia Risso) peel, a byproduct of the essential oil industry. J. Appl. Microbiol. 2007, 103, 2056–2064. [Google Scholar] [CrossRef] [PubMed]
  62. Hindi, N.; Chabuck, Z. Antimicrobial activity of different aqueous lemon extracts. J. Appl. Pharm. Sci. 2013, 3, 74–78. [Google Scholar]
  63. El-Hawary, S.; Taha, K.; Abdel-Monem, A.; Kirollos, F.; Mohamed, A. Chemical composition and biological activities of peels and leaves essential oils of four cultivars of Citrus deliciosa var. tangarina. Am. J. Essent. Oils Nat. Prod. 2013, 1, 1–6. [Google Scholar]
  64. Al-Saman, M.A.; Abdella, A.; Mazrou, K.E.; Tayel, A.A.; Irmak, S. Antimicrobial and antioxidant activities of different extracts of the peel of kumquat (Citrus japonica Thunb). J. Food Meas. Charact. 2019, 13, 3221–3229. [Google Scholar] [CrossRef]
  65. Phan, A.D.T.; Chaliha, M.; Sultanbawa, Y.; Netzel, M.E. Nutritional characteristics and antimicrobial activity of Australian grown feijoa (Acca sellowiana). Foods 2019, 8, 376. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  66. Garcia, R.; Alves, E.S.S.; Santos, M.P.; Aquije, G.M.F.V.; Fernandes, A.A.R.; Dos Santos, R.B.; Ventura, J.A.; Fernandes, P.M.B. Antimicrobial activity and potential use of monoterpenes as tropical fruits preservatives. Braz. J. Microbiol. 2008, 39, 163–168. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  67. Chabuck, Z.A.G.; Al-Charrakh, A.H.; Hindi, N.K.K.; Hindi, S.K.K. Antimicrobial effect of aqueous banana peel extract. Res. Gate Pharmceutical Sci. 2013, 1, 73–75. [Google Scholar]
  68. Mahmud, S.; Saleem, M.; Siddique, S.; Ahmed, R.; Khanum, R.; Perveen, Z. Volatile components, antioxidant and antimicrobial activity of Citrus acida var. sour lime peel oil. J. Saudi Chem. Soc. 2009, 13, 195–198. [Google Scholar] [CrossRef] [Green Version]
  69. Malviya, S.; Arvind, J.A.; Hettiarachchy, N. Antioxidant and antibacterial potential of pomegranate peel extracts. J. Food Sci. Technol. 2014, 51, 4132–4137. [Google Scholar] [CrossRef] [Green Version]
  70. Matook, S.M.; Fumio, H. Antibacterial and Antioxidant Activities of Banana (Musa, AAA cv. Cavendish) Fruits Peel. Am. J. Biochem. Biotechnol. 2005, 1, 125–131. [Google Scholar]
  71. Mehmood, T.; Afzal, A.; Anwar, F.; Iqbal, M.; Afzal, M.; Qadir, R. Variations in the Composition, Antibacterial and Haemolytic Activities of Peel Essential Oils from Unripe and Ripened Citrus limon (L.) Osbeck Fruit. J. Essent. Oil-Bear. Plants 2019, 22, 159–168. [Google Scholar] [CrossRef]
  72. Okunowo, W.O.; Oyedeji, O.; Afolabi, L.O.; Matanmi, E. Essential oil of grape fruit (Citrus paradisi) peels and its antimicrobial activities. Am. J. Plant Sci. 2013, 4, 1–9. [Google Scholar] [CrossRef] [Green Version]
  73. Fawole, O.A.; Makunga, N.P.; Opara, U.L. Antibacterial, antioxidant and tyrosinase-inhibition activities of pomegranate fruit peel methanolic extract. BMC Complement. Altern. Med. 2012, 12, 1–11. [Google Scholar] [CrossRef] [Green Version]
  74. Choi, J.G.; Kang, O.H.; Lee, Y.S.; Chae, H.S.; Oh, Y.C.; Brice, O.O.; Kim, M.S.; Sohn, D.H.; Kim, H.S.; Park, H.; et al. In Vitro and In Vivo Antibacterial Activity of Punica granatum peel Ethanol Extract against Salmonella. Evid.-Based Complement. Altern. Med. 2011, 2011, 690518. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  75. Dhanavade, D.M.; Jalkute, D.C.; Ghosh, J.; Sonawane, K. Study Antimicrobial Activity of Lemon (Citrus lemon L.) Peel Extract. Br. J. Pharmacol. Toxicol. 2011, 2, 119–122. [Google Scholar]
  76. Kanatt, S.; Chander, R.; Sharma, A. Antioxidant and antimicrobial activity of pomegranate peel extract improves the shelf life of chicken products. Int. J. Food Sci. Technol. 2010, 45, 216–222. [Google Scholar] [CrossRef]
  77. Al-Zoreky, N.S. Antimicrobial activity of pomegranate (Punica granatum L.) fruit peels. Int. J. Food Microbiol. 2009, 134, 244–248. [Google Scholar] [CrossRef]
  78. Bajpai, V.K.; Baek, K.-H.; Kang, S.C. Control of Salmonella in foods by using essential oils: A review. Food Res. Int. 2012, 45, 722–734. [Google Scholar] [CrossRef]
  79. Chouhan, S.; Sharma, K.; Guleria, S. Antimicrobial Activity of Some Essential Oils-Present Status and Future Perspectives. Med. Basel Switz. 2017, 4, 58. [Google Scholar] [CrossRef] [Green Version]
  80. Plesiat, P.; Nikaido, H. Outer membranes of Gram-negative bacteria are permeable to steroid probes. Mol. Microbiol. 1992, 6, 1323–1333. [Google Scholar] [CrossRef]
  81. Raut, J.S.; Karuppayil, S.M. A status review on the medicinal properties of essential oils. Ind. Crop. Prod. 2014, 62, 250–264. [Google Scholar] [CrossRef]
  82. Nikaido, H. Prevention of drug access to bacterial targets: Permeability barriers and active efflux. Science 1994, 264, 382–388. [Google Scholar] [CrossRef] [Green Version]
  83. Zhang, Y.; Liu, X.; Wang, Y.; Jiang, P.; Quek, S. Antibacterial activity and mechanism of cinnamon essential oil against Escherichia coli and Staphylococcus aureus. Food Control 2016, 59, 282–289. [Google Scholar] [CrossRef]
  84. Wang, X.; Shen, Y.; Thakur, K.; Han, J.; Zhang, J.G.; Hu, F.; Wei, Z.J. Antibacterial Activity and Mechanism of Ginger Essential Oil against Escherichia coli and Staphylococcus aureus. Molecules 2020, 25, 3955. [Google Scholar] [CrossRef]
  85. Bora, H.; Kamle, M.; Mahato, D.K.; Tiwari, P.; Kumar, P. Citrus Essential Oils (CEOs) and Their Applications in Food: An Overview. Plants 2020, 9, 357. [Google Scholar] [CrossRef] [Green Version]
  86. Cho, T.; Park, S.M.; Yu, H.; Seo, G.; Kim, H.; Kim, S.A.; Rhee, M. Recent Advances in the Application of Antibacterial Complexes Using Essential Oils. Molecules 2020, 25, 1752. [Google Scholar] [CrossRef] [PubMed]
  87. Kim, J.; Marshall, M.R.; Wei, C.I. Antibacterial Activity of Some Essential Oil Components against Five Foodborne Pathogens. J. Agric. Food Chem. 1995, 43, 2839–2845. [Google Scholar] [CrossRef]
  88. Griffin, S.G.; Wyllie, S.G.; Markham, J.L.; Leach, D.N. The role of structure and molecular properties of terpenoids in determining their antimicrobial activity. Flavour Fragr. J. 1999, 14, 322–332. [Google Scholar] [CrossRef]
  89. Zengin, H.; Baysal, A.H. Antibacterial and Antioxidant Activity of Essential Oil Terpenes against Pathogenic and Spoilage-Forming Bacteria and Cell Structure-Activity Relationships Evaluated by SEM Microscopy. Molecules 2014, 19, 17773–17798. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  90. Togashi, N.; Hamashima, H.; Shiraishi, A.; Inoue, Y.; Takano, A. Antibacterial activities against Staphylococcus aureus of terpene alcohols with aliphatic carbon chains. J. Essent. Oil Res. 2010, 22, 263–269. [Google Scholar] [CrossRef]
  91. Togashi, N.; Inoue, Y.; Hamashima, H.; Takano, A. Effects of Two Terpene Alcohols on the Antibacterial Activity and the Mode of Action of Farnesol against Staphylococcus aureus. Molecules 2008, 13, 3069–3076. [Google Scholar] [CrossRef] [Green Version]
  92. Akiyama, H.; Oono, T.; Huh, W.K.; Yamasaki, O.; Ogawa, S.; Katsuyama, M.; Ichikawa, H.; Iwatsuki, K. Actions of farnesol and xylitol against Staphylococcus aureus. Chemotherapy 2002, 48, 122–128. [Google Scholar] [CrossRef] [PubMed]
  93. Gomes, F.I.A.; Teixeira, P.; Azeredo, J.; Oliveira, R. Effect of farnesol on planktonic and biofilm cells of Staphylococcus epidermidis. Curr. Microbiol. 2009, 59, 118–122. [Google Scholar] [CrossRef] [Green Version]
  94. Jabra-Rizk, M.A.; Meiller, T.F.; James, C.E.; Shirtliff, M.E. Effect of farnesol on Staphylococcus aureus biofilm formation and antimicrobial susceptibility. Antimicrob. Agents Chemother. 2006, 50, 1463–1469. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  95. Saad, N.Y.; Muller, C.D.; Lobstein, A. Major bioactivities and mechanism of action of essential oils and their components. Flavour Fragr. J. 2013, 28, 269–279. [Google Scholar] [CrossRef]
  96. Lorenzi, V.; Muselli, A.; Bernardini, A.F.; Berti, L.; Pagès, J.M.; Amaral, L.; Bolla, J.M. Geraniol restores antibiotic activities against multidrug-resistant isolates from gram-negative species. Antimicrob. Agents Chemother. 2009, 53, 2209–2211. [Google Scholar] [CrossRef] [Green Version]
  97. Kumar, M.A.; Devaki, T. Geraniol, a component of plant essential oils-a review of its pharmacological activities. Int. J. Pharm. Pharm. Sci. 2015, 7, 67–70. [Google Scholar]
  98. Lieutaud, A.; Guinoiseau, E.; Lorenzi, V.; Giuliani, M.C.; Lome, V.; Brunel, J.M.; Luciani, A.; Casanova, J.; Pagès, J.M.; Berti, L.; et al. Inhibitors of antibiotic efflux by AcrAB-TolC in enterobacter aerogenes. Anti-Infect. Agents 2013, 11, 168–178. [Google Scholar] [CrossRef]
  99. Liu, X.; Cai, J.; Chen, H.; Zhong, Q.; Hou, Y.; Chen, W.; Chen, W. Antibacterial activity and mechanism of linalool against Pseudomonas aeruginosa. Microb. Pathog. 2020, 141, 103980. [Google Scholar] [CrossRef]
  100. Gao, Z.; Van Nostrand, J.D.; Zhou, J.; Zhong, W.; Chen, K.; Guo, J. Anti-listeria Activities of Linalool and Its Mechanism Revealed by Comparative Transcriptome Analysis. Front. Microbiol. 2019, 10, 2947. [Google Scholar] [CrossRef]
  101. Wang, J.-N.; Chen, W.-X.; Chen, R.-H.; Zhang, G.-F. Antibacterial activity and mechanism of limonene against Pseudomonas aeruginosa. J. Food Sci. Technol 2018, 39, 1–5. [Google Scholar]
  102. Herman, A.; Tambor, K.; Herman, A. Linalool Affects the Antimicrobial Efficacy of Essential Oils. Curr. Microbiol. 2016, 72, 165–172. [Google Scholar] [CrossRef]
  103. Silva, F.; Domingues, F.C. Antimicrobial activity of coriander oil and its effectiveness as food preservative. Crit. Rev. Food Sci. Nutr. 2017, 57, 35–47. [Google Scholar] [CrossRef]
  104. Silva, F.; Ferreira, S.; Queiroz, J.A.; Domingues, F.C. Coriander (Coriandrum sativum L.) essential oil: Its antibacterial activity and mode of action evaluated by flow cytometry. J. Med Microbiol. 2011, 60, 1479–1486. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  105. Dorman, H.J.D.; Deans, S.G. Antimicrobial agents from plants: Antibacterial activity of plant volatile oils. J. Appl. Microbiol. 2000, 88, 308–316. [Google Scholar] [CrossRef] [PubMed]
  106. Trombetta, D.; Castelli, F.; Sarpietro, M.G.; Venuti, V.; Cristani, M.; Daniele, C.; Saija, A.; Mazzanti, G.; Bisignano, G. Mechanisms of antibacterial action of three monoterpenes. Antimicrob. Agents Chemother. 2005, 49, 2474–2478. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  107. Lopez-Romero, J.C.; González-Ríos, H.; Borges, A.; Simões, M. Antibacterial Effects and Mode of Action of Selected Essential Oils Components against Escherichia coli and Staphylococcus aureus. Evid.-Based Complement. Altern. Med. 2015, 2015, 795435. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  108. Broniatowski, M.; Mastalerz, P.; Flasiński, M. Studies of the interactions of ursane-type bioactive terpenes with the model of Escherichia coli inner membrane—Langmuir monolayer approach. Biochim. Biophys. Acta 2015, 1848, 469–476. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  109. Dahham, S.S.; Tabana, Y.M.; Iqbal, M.A.; Ahamed, M.B.K.; Ezzat, M.O.; Majid, A.S.A.; Majid, A.M.S.A. The anticancer, antioxidant and antimicrobial properties of the sesquiterpene β-caryophyllene from the essential oil of Aquilaria crassna. Molecules 2015, 20, 11808–11829. [Google Scholar] [CrossRef] [PubMed]
  110. Kim, Y.S.; Park, S.J.; Lee, E.J.; Cerbo, R.M.; Lee, S.M.; Ryu, C.H.; Kim, G.S.; Kim, J.O.; Ha, Y.L. Antibacterial compounds from Rose Bengal-sensitized photooxidation of β-caryophyllene. J. Food Sci. 2008, 73, C540–C545. [Google Scholar] [CrossRef]
  111. Coman, M.M.; Oancea, A.M.; Verdenelli, M.C.; Cecchini, C.; Bahrim, G.E.; Orpianesi, C.; Cresci, A.; Silvi, S. Polyphenol content and in vitro evaluation of antioxidant, antimicrobial and prebiotic properties of red fruit extracts. Eur. Food Res. Technol. 2018, 244, 735–745. [Google Scholar] [CrossRef]
  112. Gharib, R.; Najjar, A.; Auezova, L.; Charcosset, C.; Greige-Gerges, H. Interaction of Selected Phenylpropenes with Dipalmitoylphosphatidylcholine Membrane and Their Relevance to Antibacterial Activity. J. Membr. Biol. 2017, 250, 259–271. [Google Scholar] [CrossRef]
  113. Ferreira, L.; Perestrelo, R.; Caldeira, M.; Câmara, J.S. Characterization of volatile substances in apples from Rosaceae family by headspace solid-phase microextraction followed by GC-qMS. J. Sep. Sci. 2009, 32, 1875–1888. [Google Scholar] [CrossRef] [Green Version]
  114. Matsubara, Y.; Yusa, T.; Sawabe, A.; Iizuka, Y.; Okamoto, K. Structure and Physiological Activity of Phenyl Propanoid Glycosides in Lemon (Citrus limon Burm. f.) Peel. Agric. Biol. Chem. 1991, 55, 647–650. [Google Scholar]
  115. Voo, S.S.; Grimes, H.D.; Lange, B.M. Assessing the Biosynthetic Capabilities of Secretory Glands in Citrus Peel. Plant Physiol. 2012, 159, 81–94. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  116. Atkinson, R.G. Phenylpropenes: Occurrence, Distribution, and Biosynthesis in Fruit. J. Agric. Food Chem. 2018, 66, 2259–2272. [Google Scholar] [CrossRef] [PubMed]
  117. Qian, W.; Sun, Z.; Wang, T.; Yang, M.; Liu, M.; Zhang, J.; Li, Y. Antimicrobial activity of eugenol against carbapenem-resistant Klebsiella pneumoniae and its effect on biofilms. Microb. Pathog. 2020, 139, 103924. [Google Scholar] [CrossRef]
  118. Cui, H.; Zhang, C.; Li, C.; Lin, L. Antimicrobial mechanism of clove oil on Listeria monocytogenes. Food Control 2018, 94, 140–146. [Google Scholar] [CrossRef]
  119. Ashrafudoulla, M.; Mizan, M.F.R.; Ha, A.J.-w.; Park, S.H.; Ha, S.-D. Antibacterial and antibiofilm mechanism of eugenol against antibiotic resistance Vibrio parahaemolyticus. Food Microbiol. 2020, 91, 103500. [Google Scholar] [CrossRef]
  120. Hemaiswarya, S.; Doble, M. Synergistic interaction of eugenol with antibiotics against Gram negative bacteria. Phytomedicine 2009, 16, 997–1005. [Google Scholar] [CrossRef]
  121. Hyldgaard, M.; Mygind, T.; Piotrowska, R.; Foss, M.; Meyer, R. Isoeugenol has a non-disruptive detergent-like mechanism of action. Front. Microbiol. 2015, 6, 754. [Google Scholar] [CrossRef]
  122. Marchese, A.; Barbieri, R.; Coppo, E.; Orhan, I.E.; Daglia, M.; Nabavi, S.F.; Izadi, M.; Abdollahi, M.; Nabavi, S.M.; Ajami, M. Antimicrobial activity of eugenol and essential oils containing eugenol: A mechanistic viewpoint. Crit. Rev. Microbiol. 2017, 43, 668–689. [Google Scholar] [CrossRef]
  123. Auezova, L.; Najjar, A.; Kfoury, M.; Fourmentin, S.; Greige-Gerges, H. Antibacterial activity of free or encapsulated selected phenylpropanoids against Escherichia coli and Staphylococcus epidermidis. J. Appl. Microbiol. 2020, 128, 710–720. [Google Scholar] [CrossRef]
  124. Albano, M.; Crulhas, B.P.; Alves, F.C.B.; Pereira, A.F.M.; Andrade, B.F.M.T.; Barbosa, L.N.; Furlanetto, A.; Lyra, L.P.d.S.; Rall, V.L.M.; Júnior, A.F. Antibacterial and anti-biofilm activities of cinnamaldehyde against S. epidermidis. Microb. Pathog. 2019, 126, 231–238. [Google Scholar] [CrossRef] [PubMed]
  125. Shen, S.; Zhang, T.; Yuan, Y.; Lin, S.; Xu, J.; Ye, H. Effects of cinnamaldehyde on Escherichia coli and Staphylococcus aureus membrane. Food Control 2015, 47, 196–202. [Google Scholar] [CrossRef]
  126. Yin, L.; Chen, J.; Wang, K.; Geng, Y.; Lai, W.; Huang, X.; Chen, D.; Guo, H.; Fang, J.; Chen, Z.; et al. Study the antibacterial mechanism of cinnamaldehyde against drug-resistant Aeromonas hydrophila in vitro. Microb. Pathog. 2020, 145, 104208. [Google Scholar] [CrossRef] [PubMed]
  127. Sharma, S.; Pal, R.; Hameed, S.; Fatima, Z. Antimycobacterial mechanism of vanillin involves disruption of cell-surface integrity, virulence attributes, and iron homeostasis. Int. J. Mycobacteriol. 2016, 5, 460–468. [Google Scholar] [CrossRef] [Green Version]
  128. Cushnie, T.P.T.; Lamb, A.J. Antimicrobial activity of flavonoids. Int. J. Antimicrob. Agents 2005, 26, 343–356. [Google Scholar] [CrossRef]
  129. Fathima, A.; Rao, J.R. Selective toxicity of Catechin—A natural flavonoid towards bacteria. Appl. Microbiol. Biotechnol. 2016, 100, 6395–6402. [Google Scholar] [CrossRef]
  130. Cushnie, T.; Taylor, P.; Nagaoka, Y.; Uesato, S.; Hara, Y.; Lamb, A. Investigation of the antibacterial activity of 3-O-octanoyl-(-)-epicatechin. J. Appl. Microbiol. 2008, 105, 1461–1469. [Google Scholar] [CrossRef]
  131. Tsuchiya, H.; Iinuma, M. Reduction of membrane fluidity by antibacterial sophoraflavanone G isolated from Sophora exigua. Phytomedicine 2000, 7, 161–165. [Google Scholar] [CrossRef]
  132. Dave, D.; Ghaly, A.E. Meat spoilage mechanisms and preservation techniques: A critical review. Am. J. Agric. Biol. Sci. 2011, 6, 486–510. [Google Scholar]
  133. Jayasena, D.D.; Jo, C. Essential oils as potential antimicrobial agents in meat and meat products: A review. Trends Food Sci. Technol. 2013, 34, 96–108. [Google Scholar] [CrossRef]
  134. Lucera, A.; Costa, C.; Conte, A.; Del Nobile, M.A. Food applications of natural antimicrobial compounds. Front. Microbiol. 2012, 3, 287. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  135. Krasniewska, K.; Kosakowska, O.; Pobiega, K.; Gniewosz, M. The influence of two-component mixtures from Spanish Origanum oil with Spanish Marjoram oil or coriander oil on antilisterial activity and sensory quality of a fresh cut vegetable mixture. Foods 2020, 9, 1740. [Google Scholar] [CrossRef] [PubMed]
  136. Karagozlu, N.; Ergonul, B.; Ozcan, D. Determination of antimicrobial effect of mint and basil essential oils on survival of E. coli O157:H7 and S. typhimurium in fresh-cut lettuce and purslane. Food Control 2011, 22, 1851–1855. [Google Scholar] [CrossRef]
  137. Siddiqua, S.; Anusha, B.A.; Ashwini, L.S.; Negi, P.S. Antibacterial activity of cinnamaldehyde and clove oil: Effect on selected foodborne pathogens in model food systems and watermelon juice. J. Food Sci. Technol. 2015, 52, 5834–5841. [Google Scholar] [CrossRef] [Green Version]
  138. Huq, T.; Vu, K.D.; Riedl, B.; Bouchard, J.; Lacroix, M. Synergistic effect of gamma (γ)-irradiation and microencapsulated antimicrobials against Listeria monocytogenes on ready-to-eat (RTE) meat. Food Microbiol. 2015, 46, 507–514. [Google Scholar] [CrossRef] [Green Version]
  139. Petrou, S.; Tsiraki, M.; Giatrakou, V.; Savvaidis, I.N. Chitosan dipping or oregano oil treatments, singly or combined on modified atmosphere packaged chicken breast meat. Int. J. Food Microbiol. 2012, 156, 264–271. [Google Scholar] [CrossRef]
  140. Hsouna, A.B.; Trigui, M.; Mansour, R.B.; Jarraya, R.M.; Damak, M.; Jaoua, S. Chemical composition, cytotoxicity effect and antimicrobial activity of Ceratonia siliqua essential oil with preservative effects against Listeria inoculated in minced beef meat. Int. J. Food Microbiol. 2011, 148, 66–72. [Google Scholar] [CrossRef]
  141. Hulankova, R.; Borilova, G.; Steinhauserova, I. Combined antimicrobial effect of oregano essential oil and caprylic acid in minced beef. Meat Sci. 2013, 95, 190–194. [Google Scholar] [CrossRef]
  142. Vasilatos, G.C.; Savvaidis, I.N. Chitosan or rosemary oil treatments, singly or combined to increase turkey meat shelf-life. Int. J. Food Microbiol. 2013, 166, 54–58. [Google Scholar] [CrossRef]
  143. Fernandez-Lopez, J.; Viuda-Martos, M. Introduction to the Special Issue: Application of Essential Oils in Food Systems. Foods 2018, 7, 56. [Google Scholar] [CrossRef] [Green Version]
  144. Kaur, R.; Gupta, T.B.; Bronlund, J.; Kaur, L. The potential of rosemary as a functional ingredient for meat products—A review. Food Rev. Int. 2021, 1–21. [Google Scholar] [CrossRef]
  145. Huang, X.; Lao, Y.; Pan, Y.; Chen, Y.; Zhao, H.; Gong, L.; Xie, N.; Mo, C.-H. Synergistic antimicrobial effectiveness of plant essential oil and its application in seafood preservation: A review. Molecules 2021, 26, 307. [Google Scholar] [CrossRef] [PubMed]
  146. Carpena, M.; Nuñez-Estevez, B.; Soria-Lopez, A.; Garcia-Oliveira, P.; Prieto, M.A. Essential oils and their application on active packaging systems: A review. Resources 2021, 10, 7. [Google Scholar] [CrossRef]
  147. Falleh, H.; Ben Jemaa, M.; Saada, M.; Ksouri, R. Essential oils: A promising eco-friendly food preservative. Food Chem. 2020, 330, 127268. [Google Scholar] [CrossRef] [PubMed]
  148. He, Q.; Guo, M.; Jin, T.Z.; Arabi, S.A.; Liu, D. Ultrasound improves the decontamination effect of thyme essential oil nanoemulsions against Escherichia coli O157: H7 on cherry tomatoes. Int. J. Food Microbiol. 2021, 337, 108936. [Google Scholar] [CrossRef]
  149. Kang, J.-H.; Song, K.B. Inhibitory effect of plant essential oil nanoemulsions against Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella typhimurium on red mustard leaves. Innov. Food Sci. Emerg. Technol. 2018, 45, 447–454. [Google Scholar] [CrossRef]
  150. Kang, J.-H.; Park, S.-J.; Park, J.-B.; Song, K.B. Surfactant type affects the washing effect of cinnamon leaf essential oil emulsion on kale leaves. Food Chem. 2019, 271, 122–128. [Google Scholar] [CrossRef]
  151. Yuan, W.; Teo, C.H.M.; Yuk, H.-G. Combined antibacterial activities of essential oil compounds against Escherichia coli O157:H7 and their application potential on fresh-cut lettuce. Food Control 2019, 96, 112–118. [Google Scholar] [CrossRef]
  152. Dai, J.; Li, C.; Cui, H.; Lin, L. Unraveling the anti-bacterial mechanism of Litsea cubeba essential oil against E. coli O157:H7 and its application in vegetable juices. Int. J. Food Microbiol. 2021, 338, 108989. [Google Scholar] [CrossRef]
  153. Krogsgård Nielsen, C.; Kjems, J.; Mygind, T.; Snabe, T.; Schwarz, K.; Serfert, Y.; Meyer, R.L. Antimicrobial effect of emulsion-encapsulated isoeugenol against biofilms of food pathogens and spoilage bacteria. Int. J. Food Microbiol. 2017, 242, 7–12. [Google Scholar] [CrossRef]
  154. Yoo, J.H.; Baek, K.H.; Heo, Y.S.; Yong, H.I.; Jo, C. Synergistic bactericidal effect of clove oil and encapsulated atmospheric pressure plasma against Escherichia coli O157:H7 and Staphylococcus aureus and its mechanism of action. Food Microbiol. 2021, 93, 103611. [Google Scholar] [CrossRef] [PubMed]
  155. Krichen, F.; Hamed, M.; Karoud, W.; Bougatef, H.; Sila, A.; Bougatef, A. Essential oil from pistachio by-product: Potential biological properties and natural preservative effect in ground beef meat storage. J. Food Meas. Charact. 2020, 14, 3020–3030. [Google Scholar] [CrossRef]
  156. Lin, L.; Mao, X.; Sun, Y.; Rajivgandhi, G.; Cui, H. Antibacterial properties of nanofibers containing chrysanthemum essential oil and their application as beef packaging. Int. J. Food Microbiol. 2019, 292, 21–30. [Google Scholar] [CrossRef] [PubMed]
  157. Silva, C.d.S.; Figueiredo, H.M.d.; Stamford, T.L.M.; Silva, L.H.M.d. Inhibition of Listeria monocytogenes by Melaleuca alternifolia (tea tree) essential oil in ground beef. Int. J. Food Microbiol. 2019, 293, 79–86. [Google Scholar] [CrossRef] [PubMed]
  158. Khaleque, M.A.; Keya, C.A.; Hasan, K.N.; Hoque, M.M.; Inatsu, Y.; Bari, M.L. Use of cloves and cinnamon essential oil to inactivate Listeria monocytogenes in ground beef at freezing and refrigeration temperatures. LWT 2016, 74, 219–223. [Google Scholar] [CrossRef]
  159. Chaichi, M.; Mohammadi, A.; Badii, F.; Hashemi, M. Triple synergistic essential oils prevent pathogenic and spoilage bacteria growth in the refrigerated chicken breast meat. Biocatal. Agric. Biotechnol. 2021, 32, 101926. [Google Scholar] [CrossRef]
  160. Jayari, A.; El Abed, N.; Jouini, A.; Mohammed Saed Abdul-Wahab, O.; Maaroufi, A.; Ben Hadj Ahmed, S. Antibacterial activity of Thymus capitatus and Thymus algeriensis essential oils against four food-borne pathogens inoculated in minced beef meat. J. Food Saf. 2018, 38, e12409. [Google Scholar] [CrossRef]
  161. Kazemeini, H.; Azizian, A.; Adib, H. Inhibition of Listeria monocytogenes growth in turkey fillets by alginate edible coating with Trachyspermum ammi essential oil nano-emulsion. Int. J. Food Microbiol. 2021, 344, 109104. [Google Scholar] [CrossRef]
  162. Kazemeini, H.; Azizian, A.; Shahavi, M.H. Effect of chitosan nano-gel/emulsion containing Bunium Persicum essential oil and nisin as an edible biodegradable coating on Escherichia coli O 157:H 7 in rainbow trout fillet. J. Water Environ. Nanotechnol. 2019, 4, 343–349. [Google Scholar]
  163. Noori, S.; Zeynali, F.; Almasi, H. Antimicrobial and antioxidant efficiency of nanoemulsion-based edible coating containing ginger (Zingiber officinale) essential oil and its effect on safety and quality attributes of chicken breast fillets. Food Control 2018, 84, 312–320. [Google Scholar] [CrossRef]
  164. Khezri, S.; Khezerlou, A.; Dehghan, P. Antibacterial activity of Artemisia persica Boiss essential oil against Escherichia coli O157: H7 and Listeria monocytogenes in probiotic Doogh. J. Food Process. Preserv. 2021, 45, e15446. [Google Scholar] [CrossRef]
  165. Valkova, V.; Duranova, H.; Galovicova, L.; Vukovic, N.L.; Vukic, M.; Kacaniova, M. In vitro antimicrobial activity of lavender, mint, and rosemary essential oils and the effect of their vapours on growth of Penicillium spp. In a bread model system. Molecules 2021, 26, 3859. [Google Scholar] [CrossRef] [PubMed]
  166. Ahmed, L.I.; Ibrahim, N.; Abdel-Salam, A.B.; Fahim, K.M. Potential application of ginger, clove and thyme essential oils to improve soft cheese microbial safety and sensory characteristics. Food Biosci. 2021, 42, 101177. [Google Scholar] [CrossRef]
  167. Santos, M.I.S.; Martins, S.R.; Veríssimo, C.S.C.; Nunes, M.J.C.; Lima, A.I.G.; Ferreira, R.M.S.B.; Pedroso, L.; Sousa, I.; Ferreira, M.A.S.S. Essential oils as antibacterial agents against food-borne pathogens: Are they really as useful as they are claimed to be? J. Food Sci. Technol. 2017, 54, 4344–4352. [Google Scholar] [CrossRef]
  168. Lages, L.Z.; Radünz, M.; Gonçalves, B.T.; Silva da Rosa, R.; Fouchy, M.V.; de Cássia dos Santos da Conceição, R.; Gularte, M.A.; Barboza Mendonça, C.R.; Gandra, E.A. Microbiological and sensory evaluation of meat sausage using thyme (Thymus vulgaris, L.) essential oil and powdered beet juice (Beta vulgaris L., Early Wonder cultivar). LWT 2021, 148, 111794. [Google Scholar] [CrossRef]
  169. Radunz, M.; dos Santos Hackbart, H.C.; Camargo, T.M.; Nunes, C.F.P.; de Barros, F.A.P.; Dal Magro, J.; Filho, P.J.S.; Gandra, E.A.; Radünz, A.L.; da Rosa Zavareze, E. Antimicrobial potential of spray drying encapsulated thyme (Thymus vulgaris) essential oil on the conservation of hamburger-like meat products. Int. J. Food Microbiol. 2020, 330, 108696. [Google Scholar] [CrossRef]
  170. Diarra, M.; Hassan, Y.; Block, G.; Drover, J.; Delaquis, P.; Oomah, B.D. Antibacterial activities of a polyphenolic-rich extract prepared from American cranberry (Vaccinium macrocarpon) fruit pomace against Listeria spp. LWT 2020, 123, 109056. [Google Scholar] [CrossRef]
  171. Tamkutė, L.; Gil, B.M.; Carballido, J.R.; Pukalskienė, M.; Venskutonis, P.R. Effect of cranberry pomace extracts isolated by pressurized ethanol and water on the inhibition of food pathogenic/spoilage bacteria and the quality of pork products. Food Res. Int. 2019, 120, 38–51. [Google Scholar] [CrossRef]
  172. Khanjari, A.; Bahonar, A.; Noori, N.; Siahkalmahaleh, M.R.; Rezaeigolestani, M.; Asgarian, Z.; Khanjari, J. In vitro antibacterial activity of Pimpinella anisum essential oil and its influence on microbial, chemical, and sensorial properties of minced beef during refrigerated storage. J. Food Saf. 2019, 39, e12626. [Google Scholar] [CrossRef]
  173. Sojic, B.; Pavlic, B.; Ikonić, P.; Tomovic, V.; Ikonic, B.; Zekovic, Z.; Kocic-Tanackov, S.; Jokanovic, M.; Skaljac, S.; Ivic, M. Coriander essential oil as natural food additive improves quality and safety of cooked pork sausages with different nitrite levels. Meat Sci. 2019, 157, 107879. [Google Scholar] [CrossRef]
  174. Zhang, X.; Wang, H.; Li, X.; Sun, Y.; Pan, D.; Wang, Y.; Cao, J. Effect of cinnamon essential oil on the microbiological and physiochemical characters of fresh Italian style sausage during storage. Anim. Sci. J. 2019, 90, 435–444. [Google Scholar] [CrossRef]
  175. Gniewosz, M.; Stobnicka, A. Bioactive components content, antimicrobial activity, and foodborne pathogen control in minced pork by cranberry pomace extracts. J. Food Saf. 2018, 38, e12398. [Google Scholar] [CrossRef] [Green Version]
  176. Aminzare, M.; Tajik, H.; Aliakbarlu, J.; Hashemi, M.; Raeisi, M. Effect of cinnamon essential oil and grape seed extract as functional-natural additives in the production of cooked sausage-impact on microbiological, physicochemical, lipid oxidation and sensory aspects, and fate of inoculated Clostridium perfringens. J. Food Saf. 2018, 38, e12459. [Google Scholar] [CrossRef]
  177. Ed-Dra, A.; Rhazi Filali, F.; Bou-Idra, M.; Zekkori, B.; Bouymajane, A.; Moukrad, N.; Benhallam, F.; Bebtayeb, A. Application of Mentha suaveolens essential oil as an antimicrobial agent in fresh turkey sausages. J. Appl. Biol. Biotechnol. 2018, 6, 7–12. [Google Scholar]
  178. Boskovic, M.; Djordjevic, J.; Ivanovic, J.; Janjic, J.; Zdravkovic, N.; Glisic, M.; Glamoclija, N.; Baltic, B.; Djordjevic, V.; Baltic, M. Inhibition of Salmonella by thyme essential oil and its effect on microbiological and sensory properties of minced pork meat packaged under vacuum and modified atmosphere. Int. J. Food Microbiol. 2017, 258, 58–67. [Google Scholar] [CrossRef] [PubMed]
  179. Blanco-Lizarazo, C.M.; Betancourt-Cortés, R.; Lombana, A.; Carrillo-Castro, K.; Sotelo-Díaz, I. Listeria monocytogenes behaviour and quality attributes during sausage storage affected by sodium nitrite, sodium lactate and thyme essential oil. Food Sci. Technol. Int. 2017, 23, 277–288. [Google Scholar] [CrossRef] [PubMed]
  180. Al-Sahlany, S.T.G. Effect of Mentha piperita essential oil against Vibrio spp. isolated from local cheeses. Pak. J. Food Sci. 2016, 26, 65–71. [Google Scholar]
  181. European Commission. Regulation (EC) No 1334/2008 of the European Parliament and of the Council of 16 December 2008 on Flavourings and Certain Food Ingredients with Flavouring Properties for Use in and on Foods and Amending Council Regulation (EEC) No 1601/91, Regulations (EC) No 2232/96 and (EC) No 110/2008 and Directive 2000/13/EC. 2008. Available online: (accessed on 1 January 2022).
  182. Ribeiro-Santos, R.; Andrade, M.; Melo, N.R.d.; Sanches-Silva, A. Use of essential oils in active food packaging: Recent advances and future trends. Trends Food Sci. Technol. 2017, 61, 132–140. [Google Scholar] [CrossRef]
  183. Benkhaira, N.; Koraichi, S.I.; Fikri-Benbrahim, K. In vitro methods to study antioxidant and some biological activities of essential oils: A review. Biointerface Res. Appl. Chem. 2022, 12, 3332–3347. [Google Scholar]
  184. Yang, T.; Qin, W.; Zhang, Q.; Luo, J.; Lin, D.; Chen, H. Essential-oil capsule preparation and its application in food preservation: A review. Food Rev. Int. 2022, 1–35. [Google Scholar] [CrossRef]
  185. Roda, R.; Taboada-Rodríguez, A.; Valverde-Franco, M.; Marín-Iniesta, F. Antimicrobial Activity of Vanillin and Mixtures with Cinnamon and Clove Essential Oils in Controlling Listeria monocytogenes and Escherichia coli O157:H7 in Milk. Food Bioprocess Technol. 2010, 5, 2120–2131. [Google Scholar] [CrossRef]
  186. Gutierrez, J.; Barry-Ryan, C.; Bourke, P. The antimicrobial efficacy of plant essential oil combinations and interactions with food ingredients. Int. J. Food Microbiol. 2008, 124, 91–97. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  187. Kyung, K.H. Antimicrobial properties of Allium species. Curr. Opin. Biotechnol. 2012, 23, 142–147. [Google Scholar] [CrossRef]
  188. Ruzauskas, M.; Bartkiene, E.; Stankevicius, A.; Bernatoniene, J.; Zadeike, D.; Lele, V.; Starkute, V.; Zavistanaviciute, P.; Grigas, J.; Zokaityte, E.; et al. The influence of essential oils on gut microbial profiles in pigs. Animals 2020, 10, 1734. [Google Scholar] [CrossRef]
Figure 1. Chemical composition of essential oils (EOs).
Figure 1. Chemical composition of essential oils (EOs).
Foods 11 00464 g001aFoods 11 00464 g001b
Figure 2. Schematic representation of Gram-positive and Gram-negative bacterial cell wall.
Figure 2. Schematic representation of Gram-positive and Gram-negative bacterial cell wall.
Foods 11 00464 g002
Figure 3. Antibacterial mechanism of essential oils (EOs).
Figure 3. Antibacterial mechanism of essential oils (EOs).
Foods 11 00464 g003
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Share and Cite

MDPI and ACS Style

Angane, M.; Swift, S.; Huang, K.; Butts, C.A.; Quek, S.Y. Essential Oils and Their Major Components: An Updated Review on Antimicrobial Activities, Mechanism of Action and Their Potential Application in the Food Industry. Foods 2022, 11, 464.

AMA Style

Angane M, Swift S, Huang K, Butts CA, Quek SY. Essential Oils and Their Major Components: An Updated Review on Antimicrobial Activities, Mechanism of Action and Their Potential Application in the Food Industry. Foods. 2022; 11(3):464.

Chicago/Turabian Style

Angane, Manasweeta, Simon Swift, Kang Huang, Christine A. Butts, and Siew Young Quek. 2022. "Essential Oils and Their Major Components: An Updated Review on Antimicrobial Activities, Mechanism of Action and Their Potential Application in the Food Industry" Foods 11, no. 3: 464.

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop