Encapsulation Of Essential Oils Research Articles

Polymeric Encapsulation of Mint Oil: Effect of Oil Load on the Physical Properties

Mint oil has many applications including foods, perfumes and fragrances, pharmaceuticals, cosmetics and pest control. This essential oil is easily damaged because of its high sensitivity to environmental conditions such as heat, oxygen, light and reactions with other compounds. Encapsulation provides protection of the oil against these undesirable conditions. This study was aimed at evaluating the characteristics of mint oil encapsulated in polyethylene glycol (PEG 6000) as influenced by mint oil load. Mint oil was encapsulated in polyethylene glycol at four different percentages (5.0, 7.5, 10 and 12.5%) using a melt dispersion technique. The experiment was done in two replicates. The encapsulates were characterized for their morphology, size attributes and thermal properties. Particulate sizes ranged from 281.4 – 569.5 nm and tended to increase with the increase in oil load. Microstructure of the particles examined under scanning electron microscope showed irregular flakes with sizes around 10 μm. These particles contained oil droplets in the sizes of about 200 – 500 nm as confirmed by observation with a transmission electron microscope. The enthalpy of melting of encapsulates were higher than that of mint oil, describing the enhancement of oil stability under thermal conditions. This study provides useful information in developing essential oil encapsulation for use in wider applications.

Comparative study of oregano essential oil encapsulated in halloysite nanotubes and diatomaceous earth as antimicrobial and antioxidant composites

Multifunctional composite materials with controlled release, antimicrobial and antioxidant properties were prepared through encapsulation of oregano essential oil (OEO) into diatomaceous earth (DE) and halloysite nanotubes (Hal). DE-OEO and Hal-OEO composites were compared with their physicochemical and functional properties such as the morphology and elemental analysis, zeta-potential, chemical structure, crystallinity, thermal stability, specific surface area, encapsulation efficiency, release rate, antioxidant, and antimicrobial properties. Pristine DE showed a sunflower-like shape with an average diameter of 24 μm, zeta-potential of −47.3 mV and BET of 0.87 m2/g. Whereas Hal exhibited a tubular structure with an average length of 788 nm and width of 115 nm, zeta-potential of −19.7 mV and BET of 68.5 m2/g. The morphology and crystallinity of DE and Hal did not change significantly after OEO loading, whereas FT-IR results confirmed that OEO was successfully loaded into DE and Hal. The thermal stability of OEO was improved after being encapsulated into Hal and DE. Both samples showed high antioxidant and antimicrobial activities. However, the DE-OEO sample exhibited stronger antioxidant and antimicrobial activities than Hal-OEO due to its higher encapsulation efficiency and release rate. Prepared materials can be used as a controlled-release, antioxidant, antimicrobial, nanofiller for food packaging, and drug delivery applications.

Effect of Emulsifiers and Wall Materials on Particle Size Distribution and Stability of the Blended Essential Oils Nanoemulsions

In the present work, microencapsulation of the essential oil blend (clove + lemon peel + thyme) was successfully used to produce a product that can be used as food additives or in the pharmaceutical industry for the manufacture of a food supplement or so-called nutraceutical of plant origin. The characterization of the powder of the microcapsules made it possible to observe that the essential oil was successfully incorporated into the coating matrix. This was designed by the wall material, namely maltodextrin represented a barrier allowing the protection of the active principle, the control of its release and the property retention of the encapsulated essential oil for a long time. This powder of microcapsules of essential oil mixture can be successfully used for medical purposes to remedy certain pathologies, in particular for its antioxidant, antibacterial and anti-inflammatory properties.

Encapsulation of Nepeta cataria essential oils in a chitosan nanocomposite with lethality potential against Toxoplasma gondii

Encapsulation of Nepeta cataria essential oils in a chitosan nanocomposite with lethality potential against Toxoplasma gondii

Development of a new polymer network system carrier of essential oils

The study presents the development of a new copolymacrolactone structure based on ethylene brassylate (EB) and squaric acid (SA) with different ratios between comonomers. The new system was tested as a network for essential oils encapsulation. The structure of the copolymers was confirmed by spectroscopic investigations and correlated in interdependence with the comonomers content. The interfacial characteristics of the poly(ethylene brassylate-co-squaric acid) copolymers were determined, and the transition from a moderate hydrophilic surface towards a hydrophobic region by increasing the molar content of SA comonomer was highlighted. The affinity for hydrophobic substances of the synthesised macromolecular compounds was used in a process of encapsulation of thymol (Thy) and carvacrol (CC). The newly prepared bioactive compounds were characterised by in vivo biocompatibility tests, and antimicrobial activity, Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC).

Comparative Analysis of the Antimicrobial Activity of Essential Oils and Their Formulated Microemulsions against Foodborne Pathogens and Spoilage Bacteria.

The antimicrobial activity of several essential oils (EOs) and their related microemulsions (MEs) was investigated. EOs were obtained from Cannabis sativa L. cv CS (C. sativa), Carum carvi L. (C. carvi), Crithmum maritimum L. (C. maritimum), Cuminum cyminum L. (C. cyminum), x Cupressocyparis leylandii A.B. Jacks & Dallim. (C. leylandii), Cupressus arizonica Greene (C. arizonica), Ferula assa-foetida L. (F. assa-foetida)., Ferula gummosa Boiss. (F. gummosa), Juniperus communis L. (J. communis), Juniperus x pfitzeriana (Spath) P.A. Schmidt (J. pfitzeriana), Pimpinella anisum L (P. anisum). Preliminary screening revealed that Cuminum cyminum, Crithmum maritimum, and Pimpinella anisum (10% v/v) were effective against all tested microorganisms (Escherichia coli ATCC 35218, Listeria monocytogenes ATCC 7644, Staphylococcus aureus ATCC 29213, Pseudomonas fluorescens DSM 4358, and Candida albicans ATCC 10231), with growth inhibition diameter from 10 to 25 mm. These EOs were used to formulate the MEs with an average size < 50 nm and a good stability over 30 days. EOs’ antimicrobial activity was further enhanced in the MEs, with a generalized lowering of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values. C. cyminum-ME reached, in most cases, MIC two times lower (0.312%) than the corresponding EO (0.625%) and even eight times lower against S. aureus (0.156 vs. 1.25%). A more remarkable microbicide effect was noted for C. cyminum-ME, with MBC values eight times lower (from 0.312 to 0.625%) than the corresponding EO (from 2.5 to 5%). Overall, MEs resulted in an efficient system for EOs encapsulation, enhancing solubility and lowering concentration to exert antimicrobial efficacy.

Design and characterization of whey protein nanocarriers for thyme essential oil encapsulation obtained by freeze-drying

Innovative coating powders, based on whey protein concentrate (10–15 wt%) as native (WPC) or denatured protein (d-WPC), solely or in combination with alginate (0.75 wt%, AL), containing thyme essential oil, were produced using the freeze-drying technique. The impact of individual components (protein, alginate and oil) as well as the effect of heat-induced protein denaturation, was resolved regarding physicochemical, thermal and morphological properties of powders. High product yield (∼100%), particle size (223–257 nm), low moisture content (0.10–0.13%) and zeta potential (−19 to −25.6 mV) were determined for all samples. Strong antimicrobial activity of thyme oil nanocarriers against foodborne pathogens was demonstrated. Thermogravimetric analysis (TGA) indicated enhanced thermal stability of encapsulated oil. The most specific bands of structural compounds were identified in Raman spectra of the tested formulations, but principal component analysis (PCA) on recorded spectra was necessary to show the differences between carriers of different wall materials.

Clove Essential Oil–Hydroxypropyl-β-Cyclodextrin Inclusion Complexes: Preparation, Characterization and Incorporation in Biodegradable Chitosan Films

The encapsulation of clove essential oil (CEO) in hydroxypropyl-β-cyclodextrin (HP-β-CD) and the subsequent incorporation of the inclusion complex in an elastic chitosan film in order to achieve a controlled release profile of the volatile CEO are herein presented. Freshly distilled CEO was found to contain eugenol in concentrations higher than 70%. The kneading method was implemented for the preparation of a CEO-HP-β-CD inclusion complex, resulting in a 50% inclusion efficiency of the essential oil in particles sized 214.40 nm with ζ-potential −27.5 mV. Free CEO and CEO-HP-β-CD inclusion complex were tested for their ability to scavenge the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical, and it was found that the CEO-HP-β-CD complex presented enhanced antioxidant activity (88%) compared to the free CEO (71%). Choline chloride-containing chitosan (CS) films were prepared, incorporating either the pure CEO or the CEO-HP-β-CD inclusion complex, and their mechanical properties were determined. The study of the release profile in different pH values demonstrated the capacity of the CS-HP-β-CD system to provide sustained release of CEO, noting its potential use in food processing as smart packaging.

Preparation of New Glycerol-Based Dendrimers and Studies on Their Behavior toward Essential Oil Encapsulation.

Two new families of glycerol-based dendrimers (glyceroladendrimers (GADs) and glyceroclickdendrimers (GCDs)) have been synthesized. Three generations have been isolated for each family with good yields and were fully analyzed. The encapsulation of essential oils (citronella and cinnamon) in GADs, GCDs, and also in previously described glycerodendrimers GD-PAMAMs and GD-PPIs has been studied by dynamic-headspace gas chromatography coupled to mass spectrometry. The retention rates obtained were from −35.8 to 26.65% for citronella essential oil and from 2.14 to 38.84% for the cinnamon essential oil. In addition, the best results were obtained with GD-PAMAMs and GD-PPIs of higher generation. The interaction study between essential oils or more precisely their major components have been performed through NMR spectroscopy (1H NMR and DOSY NMR). No direct interactions between dendrimers and essential oils have been observed, but a surprising behavior of compression of the dendrimer in stable emulsions was observed. Indeed, the hydrodynamic radius of GD-PPI-3 has been reduced in the presence of cinnamon essential oil.

Encapsulation of Tunisian thyme essential oil in O/W nanoemulsions: Application for meat preservation

This study aims to optimize the preparation of thyme essential oil nanoemulsion using a ternary mixture design based on the following three components: chitosan, gum Arabic and median-chain triacyglycerols (MCT). The results showed that the formulation which contained 40% chitosan, 40% gum Arabicand 20% of MCT led to a stable nanoemulsion within 30 days of storage at 4 °C. Indeed, the observed mean diameter (d[4,3]) and the polydispersity index (PDI) are the lowest with a ζ-potential value greater than +30 mV. Moreover, the amount of thyme essential oil dissolved in MCT was optimized and the 2% (w/w) was selected to prepare O/W nanoemulsion for preserving meat products. Besides, the obtained data of the chemical characteristics of meat products demonstrated that the pH, TVNB, TBARS, shear strength increased slightly and insignificantly with storage time at 4 °C.However, there was a difference between control and sample treated with nanoemulsionsin terms of physicochemical characteristics.

Preparation and Characterization of Zein Electrospun Fibers for Nano Encapsulation of Ajowan (Trachyspermum copticum L.) Essential Oil

In this study, Ajowan essential oil was encapsulated in electrospun zein fibers at different amounts of loading (0, 22, 44, and 88 mg/ml). The resulting electrospun zein fibers containing Ajowan essential oil were characterized by scanning electron microscope (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), differential Scanning Calorimetry (DSC), fourier transform infrared (FTIR). Antimicrobial properties of fibers against Staphylococcus aureus and Escherichia coli were also determined by the disc diffusion method. GC/MS analysis was employed to identify the constituents of the Ajowan essential oil. The diameters of electrospun zein fibers increased with increasing concentration of Ajowan essential oil. Physical status of Ajowan essential oil in electrospun zein fibers was determined by XRD. Thermal properties of loaded electrospun fibers were studied by DSC. FTIR approved the encapsulation of essential oil in electrospun zein fibers. The encapsulation efficiency of Ajowan essential oil in electrospun zein fibers was about 100%. Antimicrobial results showed that the Ajowan essential oil loaded electrospun fibers were effective against S. aureus and E. coli. This could be due to the major constituents of Ajowan essential oil. Ajowan essential oil was successfully encapsulated in electrospun fibers for the first time.

Droplet-based millifluidic technique for encapsulation of cinnamon essential oil: Optimization of the process and physicochemical characterization

The “millifluidic” technique could be considered as a novel approach for encapsulation of bioactive compounds and has a promising perspective in the field of food engineering or pharmaceutical science. In this study, we aim to optimize the encapsulation of cinnamon essential oil (CEO) by droplet-based millifluidic technique with four responses: encapsulation efficiency (EE), loading capacity (LC), sphericity factor (SF) and size of calcium-alginate millicapsules. The effects of alginate concentration (20–30 g/L), flow rate of alginate (1–1.6 mL/min), and flow rate of CEO (0.6–0.8 mL/min) were considered by a Box-Behnken design. The best concentration of chitosan as a coating layer on the optimized samples was selected based on the Young modulus of millicapsules. The regression models showed the significant effect (p < 0.05) of the three variables on the characteristics of millicapsules. The optimal millicapsules with 3.58 ± 0.23 mm diameter and 0.96 ± 0.01 S F showed 98.96 ± 1.2% and 70.14 ± 1.8% EE and LC, respectively. SEM images exhibited a rough external surface which changed to a rigid and smooth surface through the chitosan coating. The results of DSC and FTIR tests demonstrated the CEO entrapment in the millicapsules without any chemical interaction with the encapsulant materials. The disarray of crystallinity structure in XRD patterns revealed the successful encapsulation of CEO in the millicapsules. The non-Fickian case II in the mouth and small intestine and anomalous transport in the stomach were the main release mechanisms in the coated millicapsules. The release profile of CEO also fitted well with Ritger-Peppas model.

Stability improvement of Chinese medicinal essential oils based on delivery systems and their application in medical field

Essential oils from Chinese medicine are popular in the fields such as medicine, food, and cosmetics because of their unique biological characteristics. However, since essential oils are lipophilic compounds with high volatility, poor stability, and strong irritation, various preparation technologies need to be employed to improve stability, reduce irritation, and increase bioavailability. At present, a variety of preparation technologies have been applied to the encapsulation of essential oils. Various encapsulation strategies are formed because of different delivery systems featured with multiple principles and characteristics and are widely used to improve the stability of essential oils. Essential oils of Chinese medicine are widely used in the medical field, and they are under continuous innovation and development in clinical research, the pharmaceutical industry, medical products, etc. The present study summarized various delivery systems that could improve the stability of essential oils and reviewed the applications of essential oils encapsulated in the delivery systems in the medical field to provide re-ferences for the improvement of stability of essential oils and their safety, efficiency, and wide use in the medical field.

ENKAPSULASI SERBUK SIMPLISIA DAN EKSTRAK KULIT JERUK SERTA APLIKASINYA PADA VEGETABLES JAM

Mandarin peel contains essential oil with limonene as the dominant compound that can be used as a flavor additive and source of antioxidants in food products. Vegetables jam is an innovation of vegetable processing that requires flavor additive to increase its acceptability and quality. The aim of this study was to determine formulation, sensory, and chemical characteristics of vegetables jam with addition of encapsulated mandarin peel simplicia powder and extract. The factors that used in this study are type of active substance [simplicia powder (A1) and extract (A2)] and proportion of maltodextrin and arabic gum [1:3 (E1), 2:3 (E2), 3:3 (E3), 3:2 (E4) and 3:1 (E5)]. Based on the results of the study, vegetables jam with addition of encapsulated essential oil extract with proportion of maltodextrin and arabic gum 2:3 (A2E2) was the best treatment, where the sensory evaluation consisted of color has a score of 3.67 (orange-green to greenish orange), aroma 3.53 (slightly typical of jam to typical of jam), taste 3.00 (slightly sweet), smearing power of 4.53 (average to very average), total liking of 3.4 (slightly like to like), the water content of 77.32%, the antioxidant activity of 7.75%, beta carotene content of 15017.99 μg/100 g, and total dietary fiber content of 0.62%.&#x0D; Keywords: encapsulation, extract, mandarin peel, simplicia powder, vegetables jam

Bioactive properties of nanofibers based on poly(vinylidene fluoride) loaded with oregano essential oil: Fabrication, characterization and biological evaluation

Essential oils have promising therapeutic potentials (antioxidant, anti-inflammatory, and antibacterial activities). However, its instability (volatility and easily degradation) represents a big challenge for using them as a therapeutic agent. This study describes encapsulation of oregano essential oil (OEO) into poly(vinylidene fluoride) polymer (PVDF) through electrospinning to extend and preserve their bioactive properties (OEO@PVDF). Bead free and homogenous nanofibers formation was confirmed by scanning electron microscopy (SEM). Successful OEO incorporation was confirmed by Fourier transform infrared spectroscopy (ATR-FTIR). Hydrophobicity of OEO@PVDF nanofiber scaffold was unaffected by OEO integration. Biocompatibility of OEO@PVDF nanofiber scaffold on human normal cells (Wi-38) showed safety and apoptosis-mediated anticancer activity of OEO was enhanced. OEO@PVDF nanofiber scaffold had strong antioxidant and anti-cancer activities even after 6 months of storage at room temperature compared to OEO-free. Our study reports a simple and effective method to prepare OEO@PVDF nanofiber scaffold and opens up many new applications of essential oils for different applications.

Application of cellulose plate modified with encapsulated Cinnamomum zelanicum essential oil in active packaging of walnut kernel

In this study, Cinnamomum zelanicum essential oil was encapsulated with β-cyclodextrin and sodium caseinate (EO/BCD/Ca) and nanoemulsion was optained. In order to encapsulation of essential oil, different formulations of nanoemulsions containing essential oil were produced by ultrasound method and the effect of different polymers on the particle size and turbidity of the nanoemulsion was investigated. Scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR) techniques were used to study the structure and morphology of the produced nanoemulsions. Cinnamomum zelanicum essential oil encapsulated with β-cyclodextrin and sodium caseinate was used to modify porous cellulose plates (Cel/EO/BCD/Ca). Cellulose/encapsulated essential oil plates were used to package the walnut kernel to control oxidative changes during storage. The effect of packaging type (under vacuum and ordinal), plate type and storage time on quality control of walnut kernel and oil extracted from walnut kernel was investigated. The results showed that the particle size of essential oil, essential oil/β-cyclodextrin and essential oil/β-cyclodextrin/sodium caseinate were in the range of 84–85, 713–713 and 237–234 (nm), respectively. The encapsulation efficiency of both formulations was above 70%. Zeta potential was negative for essential oil/β-cyclodextrin/sodium caseinate samples and free essential oil samples. The effect of different polymers on the turbidity of emulsions was significant. The results of sensory evaluation of walnut kernel showed that the use of encapsulated essential oil compared to free essential oil caused the protection of color, taste and other quality characteristics during storage. Also, the essential oil encapsulated with β-cyclodextrin/sodium caseinate had a greater effect on quality control of walnut kernel and its oil than the essential oil encapsulated with β-cyclodextrin. Also, the quality characteristics of walnut kernels and walnut kernel oil packed in vacuum conditions were better than walnut kernels and walnut kernel oil packed in non-vacuum conditions during storage.

In Vitro Potential of Clary Sage and Coriander Essential Oils as Crop Protection and Post-Harvest Decay Control Products.

Owing to their various application fields and biological properties, natural products and essential oils (EO) in particular are nowadays attracting more attention as alternative methods to control plant pathogens and pests, weeds, and for post-harvest applications. Additionally, to overcome EO stability issues and low persistence of effects, EO encapsulation in β-cyclodextrin (β-CD) could represent a promising avenue. Thus, in this work, the EO distilled from two aromatic plants (Salvia sclarea L. and Coriandrum sativum L.) have been evaluated in vitro for their antifungal, herbicidal and insecticidal activities, against major plant pathogens and pests of agronomical importance. Both plants were grown on unpolluted and trace-element-polluted soils, so as to investigate the effect of the soil pollution on the EO compositions and biological effects. These EO are rich in oxygenated monoterpenes (clary sage and coriander seeds EO), or aliphatic aldehydes (coriander aerial parts EO), and were unaltered by the soil pollution. The tested EO successfully inhibited the growth of two phytopathogenic fungi, Zymoseptoria tritici and Fusarium culmorum, displaying IC50 ranging from 0.46 to 2.08 g L−1, while also exerting anti-germinative, herbicidal, repellent and fumigant effects. However, no improvement of the EO biological effects was observed in the presence of β-CD, under these in vitro experimental conditions. Among the tested EO, the one from aerial parts of coriander displayed the most significant antifungal and herbicidal effects, while the three of them exerted valuable broad-range insecticidal effects. As a whole, these findings suggest that EO produced on polluted areas can be of great interest to the agricultural area, given their faithful chemical compositions and valuable biological effects.

Encapsulation of Cumin essential oil in zein electrospun fibers: Characterization and antibacterial effect

Encapsulation of Cumin essential oil in zein electrospun fibers: Characterization and antibacterial effect

Encapsulation of thyme essential oil using electrospun zein fiber for strawberry preservation

BackgroundStrawberry is a nutrient-rich and important small fruit because of its high content of beneficial phytochemicals and several vitamins like vitamin C, vitamin E and vitamin B6. However, strawberry is highly perishable due to its susceptibility to mechanical damage, microbiological decay, and softening in texture. Recently, there has been an increasing interest in using various essential oils as natural food preservatives. Although, they have limited stability to exposure to high temperatures, light and oxygen, which could eventually affect sensory quality attributes. The electrospinning method is a simple and well-organized process that has been used to encapsulate essential oils. In this study, the effect of thyme essential oil (TEO) encapsulated into zein electrospun fiber film was assessed on extending the shelf life and preserving the quality of strawberry fruit during storage.FindingsResults indicated that TEO presented potent antibacterial activity against Bacillus cereus, Escherichia coli and Aspergillus fumigatus. The scanning electron microscopy images of zein fiber had a linear shape, absence of beads, and smooth surface. The encapsulation efficiency (EE) of TEO in the zein fiber was about 75.23%. Encapsulated TEO released at a slower rate than free TEO. The zein/TEO fibers (zein fiber film loaded with TEO) significantly (p ˂ 0.05) decreased weight loss and maintained the anthocyanin content, firmness and color of the strawberries during storage. After 15 days of storage, weight loss reduced about 15% and firmness was higher about 20% in packed fruit with zein/TEO fibers compared to control.ConclusionsInterestingly, after 15 days of cold storage, the strawberries firmness, appearance, and sensory evaluation, which are important quality factors from both postharvest and consumers’ viewpoint, in zein/TEO fiber treatment were acceptable and had higher scores compared to the control. In conclusion, the present study demonstrated the benefits of incorporating TEO into zein films, which could play a significant role in the active packaging and preservation of strawberry fruits.Graphical

The Effects of Dietary Supplementation of Encapsulated Thyme Essential Oil on Growth, Pro-Inflammatory Cytokines, and Serum Amino Acid Profiles of Broiler Chicks Challenged with Salmonella Typhimurium

Abstract Salmonella Typhimurium (S. Typhimurium) causes inflammation and has adverse effects on the growth of broiler chicks. Meanwhile, plant derivations improve the growth performance and decrease inflammation, but they do not have enough stability. Encapsulation of essential oils is a new strategy for decreasing their instability. This study was conducted to investigate the effects of dietary supplementation of encapsulated thyme essential oil (ETEO) on growth, inflammatory cytokines, and amino acid profiles of broiler chicks challenged with S. Typhimurium. Three hundred one-d-old broiler chicks were assigned into 6 groups, and 5 replications per group. The broiler chicks (3 groups) were challenged with S. Typhimurium on day 21 and birds received basal diet (positive control), encapsulated thyme (P-ETEO), and non-capsulated thyme (P-NETEO), while other groups received the same diets, but under normal as a negative control, encapsulated thyme (N-ETEO) and non-capsulated thyme (N-NETEO). Growth performance, pro-inflammatory cytokines, and serum amino acid profiles were assessed on day 42. The challenged birds in positive control showed lower growth performance, higher concentration for inflammatory cytokines, and disturbed blood serum concentrations for amino acid profiles compared to the negative control (P&lt;0.05). The result showed that dietary supplementation of the ETEO could improve growth performance and amino acid profiles, and also decrease inflammatory responses (P&lt;0.05). In sum, S. Typhimurium had negative effects on growth, immunity, and inflammation, but dietary inclusion of the ETEO could decrease its negative effects.