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Encapsulation and Technology-Based Natural Ingredients

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A special issue of Molecules (ISSN 1420-3049). This special issue belongs to the section "Materials Chemistry".

Deadline for manuscript submissions: closed (30 June 2021) | Viewed by 43969

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Prof. Dr. Filomena Barreiro

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Centro de Investigação de Montanha (CIMO) and Laboratório para a Sustentabilidade e Tecnologia em Regiões de Montanha (SusTEC), Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-253 Bragança, Portugal
Interests: biobased products; natural functional ingredients and applications; nano and microencapsulation; polyurethane chemistry; hybrid and composite materials
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Dr. Isabel P. Fernandes

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Centro de Investigação de Montanha, Instituto Politecnico de Braganca, Braganca, Portugal
Interests: polyurethane chemistry; biodegradation; green polymer processes and products; nano- and microencapsulation aplied to different industrial fields
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Natural-based ingredients are needed for different industrial fields, as they can help to overcome problems associated with the use of synthetic counterparts, including factors related to human health and work-condition risks, and decrease petroleum dependency. Nevertheless, the successful application of this renewed generation of natural ingredients depends on the development of appropriate technologies to achieved products with the required technical specifications. Among them, encapsulation processes are being increasingly applied in different industrial fields, contributing to attain product differentiation and enhance commercial value. Developing a microencapsulation process can present several constrains and challenges, as the raw materials and processes must be properly selected to avoid toxicity, conform applied legislation, and provide adequate performance to the produced systems. Further, choosing technologies and processes which are able to reach high TRLs (technology readiness levels) and perform end-use tests is of high relevance. In this context, the present Special Issue is open to contributions in the field of micro/nanoencapsulation, emulsion-based processes, particulate systems, or other relevant encapsulation strategies, directed at solving any constraint related with the direct use of natural ingredients (loss of bioactivity, solubility problem, mask odor and taste, solve problems of incompatibility, etc.), or intended to achieve target or controlled release. Moreover, it targets applications in different industrial fields, e.g., cosmetics, textiles, food, biotechnology, and the chemical industry, among others. The focus on achieving high-volume production and continuous processes to reach an industrial scale, and the use of green principles together with the integration of bio-residues in the developed processes is welcome.

Prof. Maria Filomena Barreiro
Dr. Isabel P. Fernandes
Guest Editors

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Keywords

Natural ingredients
Encapsulation strategies
Sustainable products and processes
Functional products
Industrial application
Bioeconomy

Published Papers (11 papers)

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Research

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12 pages, 1787 KiB

Open AccessArticle

Oxyresveratrol Inhibits R848-Induced Pro-Inflammatory Mediators Release by Human Dendritic Cells Even When Embedded in PLGA Nanoparticles

by Salvatore Calogero Gaglio, Marta Donini, Piyachat Evelyn Denbaes, Stefano Dusi and Massimiliano Perduca

Molecules 2021, 26(8), 2106; https://doi.org/10.3390/molecules26082106 - 07 Apr 2021

Cited by 5 | Viewed by 2941

Abstract

Oxyresveratrol, a stilbene extracted from the plant Artocarpus lakoocha Roxb., has been reported to provide a considerable anti-inflammatory activity. Since the mechanisms of this therapeutic action have been poorly clarified, we investigated whether oxyresveratrol affects the release of the pro-inflammatory cytokines IL-12, IL-6, and TNF-α by human dendritic cells (DCs). We found that oxyresveratrol did not elicit per se the release of these cytokines, but inhibited their secretion induced upon DC stimulation with R848 (Resiquimod), a well-known immune cell activator engaging receptors recognizing RNA viruses. We then investigated whether the inclusion of oxyresveratrol into nanoparticles promoting its ingestion by DCs could favor its effects on cytokine release. For this purpose we synthesized and characterized poly(lactic-co-glycolic acid) (PLGA) nanoparticles, and we assessed their effects on DCs. We found that bare PLGA nanoparticles did not affect cytokine secretion by resting DCs, but increased IL-12, IL-6, and TNF-α secretion by R848-stimulated DCs, an event known as “priming effect”. We then loaded PLGA nanoparticles with oxyresveratrol and we observed that oxyresveratrol-bearing particles did not stimulate the cytokine release by resting DCs and inhibited the PLGA-dependent enhancement of IL-12, IL-6, and TNF-α secretion by R848-stimulated DCs. The results herein reported indicate that oxyresveratrol suppresses the cytokine production by activated DCs, thus representing a good anti-inflammatory and immune-suppressive agent. Moreover, its inclusion into PLGA nanoparticles mitigates the pro-inflammatory effects due to cooperation between nanoparticles and R848 in cytokine release. Therefore, oxyresveratrol can be able to contrast the synergistic effects of nanoparticles with microorganisms that could be present in the patient tissues, therefore overcoming a condition unfavorable to the use of some nanoparticles in biological systems. Full article

(This article belongs to the Special Issue Encapsulation and Technology-Based Natural Ingredients)

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13 pages, 3845 KiB

Open AccessArticle

Liposomal Encapsulation of Carvacrol to Obtain Active Poly (Vinyl Alcohol) Films

by Johana Andrade, Chelo González-Martínez and Amparo Chiralt

Molecules 2021, 26(6), 1589; https://doi.org/10.3390/molecules26061589 - 13 Mar 2021

Cited by 7 | Viewed by 2391

Abstract

Lecithins of different origins and compositions were used for the liposomal encapsulation of carvacrol within the framework of the development of active films for food packaging. Liposomes were incorporated into aqueous polymeric solutions from fully (F) and partially (P) hydrolysed Poly (vinyl alcohol) (PVA) to obtain the films by casting. The particle size distribution and ζ-potential of the liposomal suspensions, as well as their stability over time, were evaluated. Liposomal stability during film formation was analysed through the carvacrol retention in the dried film and the film microstructure. Subtle variations in the size distributions of liposomes from different lecithins were observed. However, the absolute values of the ζ-potential were higher (−52, −57 mV) for soy lecithin (SL) liposomes, followed by those of soy lecithin enriched with phosphatidylcholine (SL-PC) (−43, −50 mV) and sunflower lecithin (SFL) (−33, −38 mV). No significant changes in the liposomal properties were observed during the study period. Lyotropic mesomorphism of lipid associations and carvacrol leakage occurred to differing extents during the film drying step, depending on the membrane lipid composition and surface charge. Liposomes obtained with SL-PC were the most effective at maintaining the stability of carvacrol emulsion during film formation, which led to the greatest carvacrol retention in the films, whereas SFL gave rise to the least stable system and the highest carvacrol losses. P-PVA was less sensitive to the emulsion destabilisation due to its greater bonding capacity with carvacrol. Therefore, P-PVA with carvacrol-loaded SL-PC liposomes has great potential to produce active films for food packaging applications. Full article

(This article belongs to the Special Issue Encapsulation and Technology-Based Natural Ingredients)

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11 pages, 1775 KiB

Open AccessCommunication

Encapsulation of Vitamin E in Yogurt-Based Beverage Emulsions: Influence of Bulk Pasteurization and Chilled Storage on Physicochemical Stability and Starter Culture Viability

by Vassilios Raikos, Lynn P. Pirie, Sati Gürel and Helen E. Hayes

Molecules 2021, 26(6), 1504; https://doi.org/10.3390/molecules26061504 - 10 Mar 2021

Cited by 11 | Viewed by 2540

Abstract

Yogurt is a nutritious food that is regularly consumed in many countries around the world and is widely appreciated for its organoleptic properties. Despite its contribution to human dietary requirements, yogurt in its traditional recipe is a poor source of fat-soluble vitamins. To respond to consumer demands and further increase the nutritional value of this product, this work aimed to fortify yogurt with vitamin E by using emulsification as the method of encapsulation. The effects of thermal processing and chilled storage on the physicochemical stability of the yogurt-based beverage was investigated. Vitamin E was only minorly affected by bulk pasteurization at 63 °C for 30 min and remained stable during storage at 4 °C for 28 days. Fortified samples showed increased in vitro antioxidant activity compared with non-fortified samples. Lactic acid bacterial counts were above the minimum recommended levels (>10⁶ cfu/g) after processing and storage. In conclusion, this work has demonstrated that emulsification can be an effective strategy for developing yogurt-based products fortified with fat soluble vitamins. Full article

(This article belongs to the Special Issue Encapsulation and Technology-Based Natural Ingredients)

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14 pages, 2786 KiB

Open AccessArticle

Cordyceps militaris Fungus Extracts-Mediated Nanoemulsion for Improvement Antioxidant, Antimicrobial, and Anti-Inflammatory Activities

by Esrat Jahan Rupa, Jin Feng Li, Muhammad Huzaifa Arif, Han Yaxi, Aditi Mitra Puja, Ahn Jong Chan, Van-An Hoang, Lalitha Kaliraj, Deok Chun Yang and Se Chan Kang

Molecules 2020, 25(23), 5733; https://doi.org/10.3390/molecules25235733 - 04 Dec 2020

Cited by 21 | Viewed by 3341

Abstract

This study aimed to produce and optimize a Cordyceps militaris-based oil-in-water (O/W) nanoemulsion (NE) encapsulated in sea buckthorn oil (SBT) using an ultrasonication process. Herein, a nonionic surfactant (Tween 80) and chitosan cosurfactant were used as emulsifying agents. The Cordyceps nanoemulsion (COR-NE) was characterized using Fourier-transform infrared spectroscopy (FT-IR), dynamic light scattering (DLS), and field-emission transmission electron microscope (FE-TEM). The DLS analyses revealed that the NE droplets were 87.0 ± 2.1 nm in diameter, with a PDI value of 0.089 ± 0.023, and zeta potential of −26.20 ± 2. The small size, low PDI, and stable zeta potential highlighted the excellent stability of the NE. The NE was tested for stability under different temperature (4 °C, 25 °C, and 60 °C) and storage conditions for 3 months where 4 °C did not affect the stability. Finally, in vitro cytotoxicity and anti-inflammatory activity were assessed. The results suggested that the NE was not toxic to RAW 264.7 or HaCaT (human keratinocyte) cell lines at up to 100 µL/mL. Anti-inflammatory activity in liposaccharides (LPS)-induced RAW 264.7 cells was evident at 50 µg/mL and showed inhibition of NO production and downregulation of pro-inflammatory gene expression. Further, the NE exhibited good antioxidant (2.96 ± 0.10 mg/mL) activity and inhibited E. coli and S. aureus bacterial growth. Overall, the COR-NE had greater efficacy than the free extract and added significant value for future biomedical and cosmetics applications. Full article

(This article belongs to the Special Issue Encapsulation and Technology-Based Natural Ingredients)

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18 pages, 3018 KiB

Open AccessFeature PaperArticle

Bio-Based Nanoparticles as a Carrier of β-Carotene: Production, Characterisation and In Vitro Gastrointestinal Digestion

by Beatriz S. Afonso, Ana G. Azevedo, Catarina Gonçalves, Isabel R. Amado, Eugénio C. Ferreira, Lorenzo M. Pastrana and Miguel A. Cerqueira

Molecules 2020, 25(19), 4497; https://doi.org/10.3390/molecules25194497 - 30 Sep 2020

Cited by 25 | Viewed by 3357

Abstract

β-carotene loaded bio-based nanoparticles (NPs) were produced by the solvent-displacement method using two polymers: zein and ethylcellulose. The production of NPs was optimised through an experimental design and characterised in terms of average size and polydispersity index. The processing conditions that allowed to obtain NPs (<100 nm) were used for β-carotene encapsulation. Then β-carotene loaded NPs were characterised in terms of zeta potential and encapsulation efficiency. Transmission electron microscopy, Fourier transform infrared spectroscopy and X-ray diffraction analysis were performed for further morphological and chemical characterisation. In the end, a static in vitro digestion following the INFOGEST protocol was performed and the bioaccessibility of β-carotene encapsulated in both NPs was determined. Results show that the best conditions for a size-controlled production with a narrow size distribution are lower polymer concentrations and higher antisolvent concentrations. The encapsulation of β-carotene in ethylcellulose NPs resulted in nanoparticles with a mean average size of 60 ± 9 nm and encapsulation efficiency of 74 ± 2%. β-carotene loaded zein-based NPs resulted in a mean size of 83 ± 8 nm and encapsulation efficiency of 93 ± 4%. Results obtained from the in vitro digestion showed that β-carotene bioaccessibility when encapsulated in zein NPs is 37 ± 1%, which is higher than the value of 8.3 ± 0.1% obtained for the ethylcellulose NPs. Full article

(This article belongs to the Special Issue Encapsulation and Technology-Based Natural Ingredients)

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16 pages, 2638 KiB

Open AccessArticle

Freeze-Drying Technique for Microencapsulation of Elsholtzia ciliata Ethanolic Extract Using Different Coating Materials

by Lauryna Pudziuvelyte, Mindaugas Marksa, Katarzyna Sosnowska, Katarzyna Winnicka, Ramune Morkuniene and Jurga Bernatoniene

Molecules 2020, 25(9), 2237; https://doi.org/10.3390/molecules25092237 - 09 May 2020

Cited by 47 | Viewed by 5266

Abstract

The present study reports on the encapsulation of Elsholtzia ciliata ethanolic extract by freeze-drying method using skim milk, sodium caseinate, gum Arabic, maltodextrin, beta-maltodextrin, and resistant-maltodextrin alone or in mixtures of two or four encapsulants. The encapsulation ability of the final mixtures was evaluated based on their microencapsulating efficiency (EE) of total phenolic compounds (TPC) and the physicochemical properties of freeze-dried powders. Results showed that the freeze-dried powders produced using two encapsulants have a lower moisture content, but higher solubility, Carr index, and Hausner ratio than freeze-dried powders produced using only one encapsulant in the formulation. The microencapsulating efficiency of TPC also varied depending on encapsulants used. The lowest EE% of TPC was determined with maltodextrin (21.17%), and the highest with sodium caseinate (83.02%). Scanning electron microscopy revealed that freeze-drying resulted in the formation of different size, irregular shape glassy particles. This study demonstrated good mucoadhesive properties of freeze-dried powders, which could be incorporated in buccal or oral delivery dosage forms. In conclusion, the microencapsulation of E. ciliata ethanolic extract by freeze-drying is an effective method to produce new value-added pharmaceutical or food formulations with polyphenols. Full article

(This article belongs to the Special Issue Encapsulation and Technology-Based Natural Ingredients)

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15 pages, 3391 KiB

Open AccessArticle

Development of Water-in-Oil Emulsions as Delivery Vehicles and Testing with a Natural Antimicrobial Extract

by Giovana Colucci, Arantzazu Santamaria-Echart, Samara C. Silva, Isabel P. M. Fernandes, Caroline C. Sipoli and Maria F. Barreiro

Molecules 2020, 25(9), 2105; https://doi.org/10.3390/molecules25092105 - 30 Apr 2020

Cited by 28 | Viewed by 5130

Abstract

Water-in-oil (W/O) emulsions have high potential for several industrial areas as delivery systems of hydrophilic compounds. In general, they are less studied than oil-in-water (O/W) systems, namely in what concerns the so-called fluid systems, partly due to problems of instability. In this context, this work aimed to produce stable W/O emulsions from a natural oil, sweet almond oil, to be further tested as vehicles of natural hydrophilic extracts, here exemplified with an aqueous cinnamon extract. Firstly, a base W/O emulsion using a high-water content (40/60, v/v) was developed by testing different mixtures of emulsifiers, namely Tween 80 combined with Span 80 or Span 85 at different contents. Among the tested systems, the one using a 54/46 (v/v) Span 80/Tween 80 mixture, and subjected to 12 high-pressure homogenizer (HPH) cycles, revealed to be stable up to 6 months, being chosen for the subsequent functionalization tests with cinnamon extract (1.25–5%; w/v; water-basis). The presence of cinnamon extract leaded to changes in the microstructure as well as in the stability. The antimicrobial and antioxidant analysis were evidenced, and a sustained behavior compatible with an extract distribution within the two phases, oil and water, in particular for the higher extract concentration, was observed. Full article

(This article belongs to the Special Issue Encapsulation and Technology-Based Natural Ingredients)

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19 pages, 4301 KiB

Open AccessArticle

Development of Chitosan/Mannitol Microparticles as Delivery System for the Oral Administration of a Spirulina Bioactive Peptide Extract

by Rita P. Aquino, Giulia Auriemma, Giulio M. Conte, Tiziana Esposito, Eduardo Sommella, Pietro Campiglia and Francesca Sansone

Molecules 2020, 25(9), 2086; https://doi.org/10.3390/molecules25092086 - 29 Apr 2020

Cited by 8 | Viewed by 3058

Abstract

Spirulina platensis contains several compounds showing nutritional and therapeutic benefits. Recently, a series of peptides able to reduce the blood pressure level and to enhance the endothelial vasorelaxation was isolated from the hydrolyzed highly water-soluble Spirulina extract (HSE). However, HSE shows critical organoleptic characteristics also having poor intestinal permeability, limiting absorption when orally delivered. This research aims to overcome the critical issues through the encapsulation of HSE in Chitosan/Mannitol—(CM)-based microparticles by spray drying. The produced powders (CM-HSE) showed good process yield (≈70%) and encapsulation efficiency (≈100%) also having good derived flow properties as well as stability up to six months storage. The microparticles constituting the spray-dried powder resulted in an amorphous micrometric state (d₅₀ ≈ 14 µm) able to retain dark colour and unpleasant smell of raw HSE. Moreover, the in vitro permeation study by Franz cell indicated that the engineered microparticles are able to enhance the permeation of HSE through an intestinal biomimetic barrier (551.13 μg/cm² CM-HSE vs. 315.46 μg/cm² HSE at 270 min). Full article

(This article belongs to the Special Issue Encapsulation and Technology-Based Natural Ingredients)

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14 pages, 3774 KiB

Open AccessFeature PaperArticle

Formulation and Optimization of Nanoemulsions Using the Natural Surfactant Saponin from Quillaja Bark

by Tatiana B. Schreiner, Arantzazu Santamaria-Echart, Andreia Ribeiro, António M. Peres, Madalena M. Dias, Simão P. Pinho and Maria Filomena Barreiro

Molecules 2020, 25(7), 1538; https://doi.org/10.3390/molecules25071538 - 27 Mar 2020

Cited by 36 | Viewed by 4500

Abstract

Replacing synthetic surfactants by natural alternatives when formulating nanoemulsions has gained attention as a sustainable approach. In this context, nanoemulsions based on sweet almond oil and stabilized by saponin from Quillaja bark with glycerol as cosurfactant were prepared by the high-pressure homogenization method. The effects of oil/water (O/W) ratio, total surfactant amount, and saponin/glycerol ratio on their stability were analyzed. The formation and stabilization of the oil-in-water nanoemulsions were analyzed through the evaluation of stability over time, pH, zeta potential, and particle size distribution analysis. Moreover, a design of experiments was performed to assess the most suitable composition based on particle size and stability parameters. The prepared nanoemulsions are, in general, highly stable over time, showing zeta potential values lower than −40 mV, a slight acid behavior due to the character of the components, and particle size (in volume) in the range of 1.1 to 4.3 µm. Response surface methodology revealed that formulations using an O/W ratio of 10/90 and 1.5 wt% surfactant resulted in lower particle sizes and zeta potential, presenting higher stability. The use of glycerol did not positively affect the formulations, which reinforces the suitability of preparing highly stable nanoemulsions based on natural surfactants such as saponins. Full article

(This article belongs to the Special Issue Encapsulation and Technology-Based Natural Ingredients)

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20 pages, 3358 KiB

Open AccessArticle

Encapsulation of Vitamins A and E as Spray-Dried Additives for the Feed Industry

by Javiera Mujica-Álvarez, O. Gil-Castell, Pabla A. Barra, A. Ribes-Greus, Rubén Bustos, Mirko Faccini and Silvia Matiacevich

Molecules 2020, 25(6), 1357; https://doi.org/10.3390/molecules25061357 - 17 Mar 2020

Cited by 29 | Viewed by 4687

Abstract

Encapsulated fat-soluble powders containing vitamin A (VA) and E (VE) were prepared as a feasible additive for extruded feed products. The effect of the encapsulating agents (Capsul-CAP^®, sodium caseinate-SC) in combination with Tween 80 (TW) as an emulsifier and maltodextrin (MD) as a wall material on the physicochemical properties of emulsions and powders was evaluated. First, nanoemulsions containing MD:CAP:TW:VA/VE and MD:SC:TW:VA/VE were prepared and characterized. Then, powders were obtained by means of spray-drying and analyzed in terms of the product yield, encapsulation efficiency, moisture content, porosity, surface morphology, chemical structure, and thermal properties and thermo-oxidative/thermal stability. Results showed that although nanoemulsions were obtained for all the compositions, homogeneous microcapsules were found after the drying process. High product yield and encapsulation efficiency were obtained, and the presence of the vitamins was corroborated. The characteristics of the powders were mainly influenced by the encapsulating agent used and also by the type of vitamin. In general, the microcapsules remained thermally stable up to 170 °C and, therefore, the proposed encapsulation systems for vitamins A and E were suitable for the preparation of additives for the feed manufacturing through the extrusion process. Full article

(This article belongs to the Special Issue Encapsulation and Technology-Based Natural Ingredients)

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Review

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25 pages, 942 KiB

Open AccessReview

Natural Ingredient-Based Polymeric Nanoparticles for Cancer Treatment

by Ka Hong Wong, Aiping Lu, Xiaoyu Chen and Zhijun Yang

Molecules 2020, 25(16), 3620; https://doi.org/10.3390/molecules25163620 - 09 Aug 2020

Cited by 60 | Viewed by 5198

Abstract

Cancer is a global health challenge. There are drawbacks to conventional chemotherapy such as poor bioavailability, development of drug resistance and severe side effects. Novel drug delivery system may be an alternative to optimize therapeutic effects. When such systems consist of natural materials, they offer important advantages: they are usually highly biocompatible, biodegradable, nontoxic and nonimmunogenic. Furthermore, natural materials can be easily modified for conjugation with a wide range of therapeutic agents and targeting ligands, according to the therapeutic purpose. This article reviews different natural ingredients and their applications in drug delivery systems for cancer therapy. Firstly, an overview of the polysaccharides and protein-based polymers that have been extensively investigated for drug delivery are described. Secondly, recent advances in using various natural ingredient-based polymeric nanoparticles for cancer therapy are reviewed. The characteristics of these delivery systems are summarized, followed by a discussion of future development and clinical potential. This review aims to summarize current knowledge and provide a basis for developing effective tailor-made formulations for cancer therapy in the future. Full article

(This article belongs to the Special Issue Encapsulation and Technology-Based Natural Ingredients)

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