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Plant Extracts as Source of Bioactive Compounds and Their Beneficial Effects on Human Health

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A special issue of Plants (ISSN 2223-7747). This special issue belongs to the section "Phytochemistry".

Deadline for manuscript submissions: closed (20 February 2023) | Viewed by 16382

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Dr. Jessica Maiuolo

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Laboratory of Pharmaceutical Biology, IRC-FSH Center, Department of Health Sciences, University "Magna Græcia" of Catanzaro, Germaneto, 88100 Catanzaro, Italy
Interests: plant extract; polyphenols; neurodegeneration; human health; microbiota
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Dr. Vincenzo Musolino

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Laboratoy of Pharmaceutical Biology, IRC-FSH, Department of Health Sciences, University "Magna Græcia" of Catanzaro, Catanzaro, Italy
Interests: medicinal plants; extraction and isolation of compounds of natural origin; phytochemical analysis; biological activity
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Dr. Natalizia Miceli

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Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, 98168 Messina, Italy
Interests: medicinal and aromatic plants; ethnobotanical uses; plant extracts; bioactive compounds; polyphenols; nutraceuticals
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Dear Colleagues,

The protective effects of plants and their extracts on human health are well known, and knowledge on them has increased over the last two decades. These effects are justified by the countless beneficial properties recognized in plants, including antioxidant, anti-inflammatory, analgesic, antimicrobial, antidiabetic, and anticancer properties, regulating the extra- and intercellular signaling pathways. Most of these activities are due to the components present in plants, such as their secondary metabolism products, polyphenols. Polyphenols consist, as the name indicates, of a set of phenolic structures, in which an OH group replaces a benzene hydrogen atom and whose chemical formula is C₆H₅OH. For this reason, it would be interesting to discover the properties of a plant species, obtain its extract from the main organs of the plant under examination, and test it, accordingly, on in vitro, in vivo, or clinical models in pathological conditions. It is important to stress, however, that not only polyphenols, but also all of the components of the extract as a whole are responsible for the beneficial properties induced by plants. Therefore, it is important to correctly know the composition of the extract, which should be quite unchanged, despite some variables (seasonality, composition, or pH of the soil in which the plant lives, the method of sampling the organ from which the extract is to be obtained, the exposure of the plant to sunlight, etc.). A standard extraction protocol should be recognized and used unequivocally, in order to obtain a highly reliable extract. Another objective variable related to the use of plant extracts is their bioavailability in the body. For example, after ingestion, their various components can be transformed by enzymatic activity, before being partially or totally absorbed in the small intestine or colon, where they are also subject to the action of the intestinal microbiota. Finally, the third step would be to use plant extracts as potential substitutes or adjuvants of drug therapy. All synthetic drugs currently in use, in addition to carrying out the action for which they are taken, develop side effects that often lead to drug replacement, dosage reduction, or an impaired quality of life. The purpose of this Special Issue of Plants is to explore one or more of the following questions:

1) Is it possible to develop standardized protocols to obtain plant extracts? It would be interesting to describe and make known the operational strategies to the scientific community.

2) Is it possible to trace the bioavailability of plant extracts qualitatively and quantitatively? It would be important to know if something similar has already been carried out.

3) Is it possible to test the effects of plant extracts on human health in the event of proven disease? It would be interesting to know what is already known scientifically.

Dr. Jessica Maiuolo
Dr. Vincenzo Musolino
Dr. Natalizia Miceli
Guest Editors

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Published Papers (9 papers)

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Research

14 pages, 1986 KiB

Open AccessArticle

Ferula communis Root Extract: In Vitro Evaluation of the Potential Additive Effect with Chemotherapy Tamoxifen in Breast Cancer (MCF-7) Cells Part II

by Jessica Maiuolo, Natalizia Miceli, Federica Davì, Irene Bava, Luigi Tucci, Salvatore Ragusa, Maria Fernanda Taviano, Vincenzo Musolino, Micaela Gliozzi, Cristina Carresi, Roberta Macrì, Federica Scarano, Anna Rita Coppoletta, Antonio Cardamone, Carolina Muscoli, Ezio Bombardelli, Ernesto Palma and Vincenzo Mollace

Plants 2023, 12(5), 1194; https://doi.org/10.3390/plants12051194 - 06 Mar 2023

Cited by 2 | Viewed by 2083

Abstract

Ferula L., belonging to the Apiaceae family, is represented by about 170 species predominantly present in areas with a mild–warm–arid climate, including the Mediterranean region, North Africa and Central Asia. Numerous beneficial activities have been reported for this plant in traditional medicine, including antidiabetic, antimicrobial, antiproliferative, anti-dysentery, stomachache with diarrhea and cramps remedies. FER-E was obtained from the plant F. communis, and precisely from the root, collected in Sardinia, Italy. A total of 25 g of root was mixed with 125 g of acetone (ratio 1:5, room temperature). The solution was filtered, and the liquid fraction was subjected to high pressure liquid chromatographic separation (HPLC). In particular, 10 mg of dry root extract powder, from F. communis, was dissolved in 10.0 mL of methanol, filtered with a 0.2 µm PTFE filter and subjected to HPLC analysis. The net dry powder yield obtained was 2.2 g. In addition, to reduce the toxicity of FER-E, the component ferulenol was removed. High concentrations of FER-E have demonstrated a toxic effect against breast cancer, with a mechanism independent of the oxidative potential, which is absent in this extract. In fact, some in vitro tests were used and showed little or no oxidizing activity by the extract. In addition, we appreciated less damage on the respective healthy cell lines (breast), assuming that this extract could be used for its potential role against uncontrolled cancer growth. The results of this research have also shown that F. communis extract could be used together with tamoxifen, increasing its effectiveness, and reducing side effects. However, further confirmatory experiments should be carried out. Full article

(This article belongs to the Special Issue Plant Extracts as Source of Bioactive Compounds and Their Beneficial Effects on Human Health)

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19 pages, 4131 KiB

Open AccessArticle

Hyptis obtusiflora C. Presl ex Benth Methanolic Extract Exhibits Anti-Inflammatory and Anti-Gastritis Activities via Suppressing AKT/NF-κB Pathway

by Jieun Oh, Jae Youl Cho and Daewon Kim

Plants 2023, 12(5), 1146; https://doi.org/10.3390/plants12051146 - 02 Mar 2023

Cited by 1 | Viewed by 1349

Abstract

Inflammation is an indispensable part of the human body’s self-defense mechanism against external stimuli. The interactions between Toll-like receptors and microbial components trigger the innate immune system via NF-κB signaling, which regulates the overall cell signaling including inflammatory responses and immune modulations. The anti-inflammatory effects of Hyptis obtusiflora C. Presl ex Benth, which has been used as a home remedy for gastrointestinal disorders and skin disease in rural areas of Latin America, have not yet been studied. Here, we investigate the medicinal properties of Hyptis obtusiflora C. Presl ex Benth methanol extract (Ho-ME) for inflammatory response suppression. Nitric oxide secretion in RAW264.7 cells triggered by TLR2, 3, or 4 agonists was reduced by Ho-ME. Reduction of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, and interleukin (IL)-1b mRNA expression was observed. Decreased transcriptional activity in TRIF- and MyD88-overexpressing HEK293T cells was detected with a luciferase assay. Additionally, serially downregulated phosphorylation of kinase in the NF-κB pathway by Ho-ME was discovered in lipopolysaccharide-treated RAW264.7 cells. Together with the overexpression of its constructs, AKT was identified as a target protein of Ho-ME, and its binding domains were reaffirmed. Moreover, Ho-ME exerted gastroprotective effects in an acute gastritis mouse model generated by the administration of HCl and EtOH. In conclusion, Ho-ME downregulates inflammation via AKT targeting in the NF-κB pathway, and the combined results support Hyptis obtusiflora as a new candidate anti-inflammatory drug. Full article

(This article belongs to the Special Issue Plant Extracts as Source of Bioactive Compounds and Their Beneficial Effects on Human Health)

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23 pages, 5157 KiB

Open AccessArticle

Chemopreventive Activity of Ellagitannins from Acer pseudosieboldianum (Pax) Komarov Leaves on Prostate Cancer Cells

by Se-Yeon Son, Jin-Hyeok Choi, Eun-Bin Kim, Jun Yin, Seo-Yeon Seonu, Si-Yeon Jin, Jae-Yoon Oh and Min-Won Lee

Plants 2023, 12(5), 1047; https://doi.org/10.3390/plants12051047 - 24 Feb 2023

Cited by 2 | Viewed by 1404

Abstract

Several studies have shown that compounds from Acer pseudosieboldianum (Pax) Komarov leaves (APL) display potent anti-oxidative, anti-inflammatory, and anti-proliferative activities. Prostate cancer (PCa) is the most common cancer among older men, and DNA methylation is associated with PCa progression. This study aimed to investigate the chemopreventive activities of the compounds which were isolated from APL on prostate cancer cells and elucidate the mechanisms of these compounds in relation to DNA methylation. One novel ellagitannin [komaniin (14)] and thirteen other known compounds, including glucose derivatives [ethyl-β-D-glucopyranose (3) and (4R)-p-menth-1-ene-7,8-diol 7-O-β-D-glucopyranoside (4)], one phenylpropanoid [junipetrioloside A (5)], three phenolic acid derivatives [ellagic acid-4-β-D-xylopyranoside (1), 4-O-galloyl-quinic acid (2), and gallic acid (8)], two flavonoids [quercetin (11) and kaempferol (12)], and five hydrolysable tannins [geraniin (6), punicafolin (7), granatin B (9), 1,2,3,4,6-penta-galloyl-β-D-glucopyranoside (10), and mallotusinic acid (13)] were isolated from APL. The hydrolyzable tannins (6, 7, 9, 10, 13, and 14) showed potent anti-PCa proliferative and apoptosis-promoting activities. Among the compounds, the ellagitannins in the dehydrohexahydroxydiphenoyl (DHHDP) group (6, 9, 13, and 14), the novel compound 14 showed the most potent inhibitory activity on DNA methyltransferase (DNMT1, 3a and 3b) and glutathione S-transferase P1 methyl removing and re-expression activities. Thus, our results suggested that the ellagitannins (6, 9, 13, and 14) isolated from APL could be a promising treatment option for PCa. Full article

(This article belongs to the Special Issue Plant Extracts as Source of Bioactive Compounds and Their Beneficial Effects on Human Health)

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23 pages, 16804 KiB

Open AccessArticle

Nocellara Del Belice (Olea europaea L. Cultivar): Leaf Extract Concentrated in Phenolic Compounds and Its Anti-Inflammatory and Radical Scavenging Activity

by Vincenzo Musolino, Roberta Macrì, Antonio Cardamone, Maria Serra, Anna Rita Coppoletta, Luigi Tucci, Jessica Maiuolo, Carmine Lupia, Federica Scarano, Cristina Carresi, Saverio Nucera, Irene Bava, Mariangela Marrelli, Ernesto Palma, Micaela Gliozzi and Vincenzo Mollace

Plants 2023, 12(1), 27; https://doi.org/10.3390/plants12010027 - 21 Dec 2022

Cited by 6 | Viewed by 1867

Abstract

Olea europaea L. is a plant belonging to the Oleaceae family, widely grown around the Mediterranean Basin and its leaves are a source of phenolic compounds with antioxidant and anti-inflammatory capacity. Among these, oleuropein and luteolin-7-O-glucoside represent two major polyphenolic compounds in olive-leaf extract. Herein, a polystyrene resin was used to recover the polyphenolic fraction from the acetone-water leaf extract from Nocellara del Belice cultivar, which showed the higher level of analysed bioactive compounds, compared to Carolea cultivar. The antioxidant activity of the extract concentrated in phenolic compounds (OLECp) was evaluated through a classical assay and electron paramagnetic resonance (EPR) for DPPH and hydroxyl radicals scavenging. Thus, the anti-inflammatory activity and the potential beneficial effects in reducing lipid accumulation in an in vitro model of NAFLD using McA-RH7777 cells exposed to oleic acid (OA) were evaluated. Nile Red and Oil Red O have been used to stain the lipid accumulation, while the inflammatory status was assessed by Cytokines Bioplex Assay. OLECp (TPC: 92.93 ± 9.35 mg GAE/g, TFC: 728.12 ± 16.04 mg RE/g; 1 g of extract contains 315.250 mg of oleuropein and 17.44 mg of luteolin-7-O-glucoside) exerted a good radical scavenging capability (IC₅₀: 2.30 ± 0.18 mg/mL) with a neutralizing power against DPPH and hydroxyl radicals, as confirmed by the decreased signal area of the EPR spectra. Moreover, OLECp at concentration of 25, 50 and 100 μg/mL counteracted the intracellular inflammatory status, as result of decreased intracellular lipid content. Our results highlighted the multiple properties and applications of an O. europaea extract concentrated in polyphenols, and the possibility to formulate novel nutraceuticals with antioxidant properties, destined to ameliorate human health. Full article

(This article belongs to the Special Issue Plant Extracts as Source of Bioactive Compounds and Their Beneficial Effects on Human Health)

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12 pages, 2356 KiB

Open AccessArticle

Amaryllidaceae Alkaloids from Clivia miniata (Lindl.) Bosse (Amaryllidaceae): Isolation, Structural Elucidation, and Biological Activity

by Marcela Šafratová, Jana Křoustková, Negar Maafi, Daniela Suchánková, Rudolf Vrabec, Jakub Chlebek, Jiří Kuneš, Lubomír Opletal, Franz Bucar and Lucie Cahlíková

Plants 2022, 11(22), 3034; https://doi.org/10.3390/plants11223034 - 10 Nov 2022

Cited by 4 | Viewed by 1826

Abstract

Clivia miniata (Amaryllidaceae) is an herbaceous evergreen flowering plant that is endemic to South Africa and Swaziland and belongs to one of the top-10 traded medicinal plants in informal medicine markets in South Africa. The species has been reported as the most important component of a traditional healer’s pallet of healing plants. Eighteen known Amaryllidaceae alkaloids (AAs) of various structural types, and one undescribed alkaloid of homolycorine-type, named clivimine B (3), were isolated from Clivia miniata. The chemical structures of the isolated alkaloids were elucidated by a combination of MS, HRMS, 1D and 2D NMR techniques and by comparison with literature data. Compounds isolated in a sufficient quantity, and not tested previously, were evaluated for their in vitro acetylcholinesterase (AChE; E.C. 3.1.1.7) and butyrylcholinesterase (BuChE; E.C. 3.1.1.8) inhibition activities. Full article

(This article belongs to the Special Issue Plant Extracts as Source of Bioactive Compounds and Their Beneficial Effects on Human Health)

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12 pages, 265 KiB

Open AccessArticle

Essential Oil and Hydrosol Composition of Immortelle (Helichrysumitalicum)

by Nina Kunc, Antonela Frlan, Dea Baričevič, Nina Kočevar Glavač and Meta Kokalj Ladan

Plants 2022, 11(19), 2573; https://doi.org/10.3390/plants11192573 - 29 Sep 2022

Cited by 5 | Viewed by 1655

Abstract

The chemical composition of essential oils and hydrosols of immortelle (Helichrysum italicum) stems with leaves obtained by hydrodistillation was identified using gas chromatography coupled with mass spectrometry (GC-MS). One-year-old and two-year-old plants of the same immortelle population, and plants from three Croatian populations, all grown in Slovenia, were included in the study. The main compounds of essential oils of one-year-old and two-year-old plants were α-pinene, α-eudesmol, and rosifoliol. Among essential oils of the Croatian populations, three dominant components were found: α-pinene, geranyl acetate, and 2-phenylethyl tiglate. Both the essential oils and hydrosols of one-year-old plants were more diverse in their compositions than two-year-old plants. The predominant compounds of hydrosols of one- and two-year-old plants were pentan-3-one, 3-octanone, 2,2-dimethylnon-5-en-3-one, and α-terpineol, and in the Croatian populations α-terpineol, 2,6-octadien-1-ol, 2,2-dimethylnon-5-en-3-one, and α-terpineol. Full article

(This article belongs to the Special Issue Plant Extracts as Source of Bioactive Compounds and Their Beneficial Effects on Human Health)

16 pages, 416 KiB

Open AccessArticle

Impact of 3-Year Period as a Factor on the Content of Biologically Valuable Substances in Seeds of White Lupin

by Ivana Tirdiľová, Alena Vollmannová, Silvia Čéryová, Peter Obtulovič, Július Árvay and Erika Zetochová

Plants 2022, 11(16), 2087; https://doi.org/10.3390/plants11162087 - 10 Aug 2022

Cited by 2 | Viewed by 1369

Abstract

White lupin seed is a unique legume rich in protein and fiber contents, as well as phytochemicals with health potential that contributes to a reduced risk of dyslipidemia, obesity and intestinal dysfunction. This study was focused on the effect of the year on the contents of caffeic acid, 4-hydroxybenzoic acid, trans-ferulic, trans-p-coumaric, quercetin, myricetin, kaempferol, apigenin and genistein, as well as the antioxidant activity and total polyphenols, of seeds of eleven varieties (Lupine albus). The contents of individual phenolic substances were determined by high-performance liquid chromatography–HPLC. The total content of polyphenols and the antioxidant activity were determined spectrophotometrically. The results show that the lowest contents of phenolic acids were found in the seeds from 2018. The caffeic acid and trans-ferulic acid were the most represented among all phenolic acids, during all 3 monitored years (2017, 2018, and 2019). Our results confirm the significant influence of the year of cultivation on the bioactive substances’ content in the seeds, and this can be potentially useful for the appropriate selection of locations for lupine growers in Slovakia, taking into account the climatic conditions of the given location. This study provides information about a legume that is underutilized in human nutrition, which may be a valuable source of bioactive substances. Full article

(This article belongs to the Special Issue Plant Extracts as Source of Bioactive Compounds and Their Beneficial Effects on Human Health)

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14 pages, 2012 KiB

Open AccessArticle

Ferula communis L. (Apiaceae) Root Acetone-Water Extract: Phytochemical Analysis, Cytotoxicity and In Vitro Evaluation of Estrogenic Properties

by Jessica Maiuolo, Vincenzo Musolino, Lorenza Guarnieri, Roberta Macrì, Anna Rita Coppoletta, Antonio Cardamone, Maria Serra, Micaela Gliozzi, Irene Bava, Carmine Lupia, Luigi Tucci, Ezio Bombardelli and Vincenzo Mollace

Plants 2022, 11(15), 1905; https://doi.org/10.3390/plants11151905 - 22 Jul 2022

Cited by 4 | Viewed by 1808

Abstract

Ferula communis L. (F. communis) belongs to the Apiaceae family and is a herbaceous plant with various pharmaceutical properties, due to the different contents of bioactive compounds extracted mainly from its roots, as well as its leaves and rhizome. To date, this plant extract has demonstrated estrogenic, anti-inflammatory, antiproliferative, cytotoxic, antimicrobial and anti-neoplastic properties. Its estrogenic activity is justified by the presence of ferutinin, an ester of a sesquiterpenic alcohol that acts as an agonist for estrogen receptors, with a chemical formula equal to C₂₂H₃O₄. The component present in F. communis responsible for the toxicity of the plant is ferulenol, a prenylated coumarin with the chemical formula C₂₄H₃₀O₃. This compound is capable of inducing mortality via its strong anti-coagulant properties, leading to a lethal hemorrhagic syndrome, ferulosis, in animals that feed on a chemotype of F. communis containing a high amount of ferulenol. The removal of the component ferulenol makes extracts of Ferula non-toxic. In fact, the remaining prenylated coumarins are not present in concentrations sufficient to induce toxicity. The intake of high concentrations of the extract of this plant leads a double dose-dependent effect that is typical of sesquiterpenes such as ferutinin. Here, we assessed the cytotoxicity and the estrogenic properties of the F. communis phytocomplex obtained through extraction using a mixture of acetone and water. Among the active constituents of F. communis, the identification of ferutinin and ferulenol was performed using HPLC. The effects of the extract were evaluated, following the removal of ferulenol, on three cell lines: human breast cancer MCF-7, human cervical cancer HeLa and human osteoblastic sarcoma Saos-2. The choice of these cell lines was justified by the need to mimic certain processes which may occur in vivo and which are estrogen-dependent. The obtained results demonstrated that F. communis extract, in addition to possessing an estrogenic-like property, showed a dose-dependent effect. Low concentrations (0.1–0.8 μM) demonstrated a hyperproliferative effect, whereas higher concentrations (1.6–50 μM) were toxic. Therefore, this extract could be an excellent candidate to make up for a reduction or lack of estrogen. Full article

(This article belongs to the Special Issue Plant Extracts as Source of Bioactive Compounds and Their Beneficial Effects on Human Health)

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18 pages, 2865 KiB

Open AccessArticle

Potentilla paradoxa Nutt. Ethanol Extract Exhibits Anti-Inflammatory Effects by Suppression of the Src/NF-κB Signaling Pathway

by Ji Won Kim, Ki Woong Kwon, Mi-Yeon Kim and Jae Youl Cho

Plants 2022, 11(13), 1750; https://doi.org/10.3390/plants11131750 - 30 Jun 2022

Cited by 3 | Viewed by 1904

Abstract

Inflammation is an immune response that protects against harmful stimuli. However, severe inflammation can cause many diseases, such as diabetes, cancer, and arthritis. In this study, we examined the anti-inflammatory efficacy and mechanism of Potentilla paradoxa Nutt. ethanol extract (Pp-EE) as a new strategy for controlling the inflammatory response. Cellular activities and the molecular target of Pp-EE were identified in RAW264.7 cells and HEK293T cells. The effect of Pp-EE was analyzed using the Griess assay, the luciferase assay, reverse transcription-polymerase chain reaction, and Western blotting. To evaluate the in vivo effects, an HCl/EtOH-induced gastritis mouse model was used. NO production and pro-inflammatory gene (iNOS, COX-2, and TNF-α) mRNA levels were decreased by Pp-EE in a concentration-dependent manner without showing cytotoxicity. The activation of the transcription factor, particularly NF-κB, was effectively suppressed by Pp-EE. It was also found that Pp-EE directly inhibits the activation of Src in lipopolysaccharide (LPS)-treated RAW264.7 cells and in Src-overexpressed HEK293 cells by Western blotting analysis and cellular thermal shift assay. Experiments in the gastritis mouse model indicated that Pp-EE suppresses HCl/EtOH-induced gastric lesions, the expression levels of COX-2, IL-6, and TNF-α, and the phosphorylation of p65, p50, and Src. Taken together, these results suggest that Pp-EE can be applied as an anti-inflammatory remedy with a Src/NF-κB inhibitory property. Full article

(This article belongs to the Special Issue Plant Extracts as Source of Bioactive Compounds and Their Beneficial Effects on Human Health)

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