Application of microencapsulated essential oils in cosmetic and personal healthcare products – a review

Nowadays, the consumers around the world are increasingly focused on health and beauty. The renewed consumer interest in natural cosmetic products creates the demand for new products and reformulated others with botanical and functional ingredients. In cosmetic products, essential oils (EOs) play a major role as fragrance ingredients. They can optimize its proprieties and preservation, as well as the marketing image of the final product. Microencapsulation of EOs can protect and prevent the loss of volatile aromatic ingredients and improve the controlled release and stability of this core materials. The importance of EOs for cosmetic industry and its microencapsulation was reviewed in this study. Also a briefly introduction about the preparation of microparticles was presented. Some of the most important and usual microencapsulation techniques of EOs, as well as the conventional encapsulating agents, were discussed. Despite the fact that microencapsulation of EOs is a very promising and extremely attractive application area for cosmetic industry, further basic research needs to be carried out, for a better understanding of the biofunctional activities of microencapsulated EOs and its release modulation, as well as the effects of others cosmetic ingredients and the storage time in the microparticles properties.     

Chemical composition and antimicrobial activity of essential oils of Thymus algeriensis,Eucalyptus globulus and Rosmarinus officinalis from Morocco

BACKGROUND: The present study reports on the antimicrobial activity and chemical composition of the essential oils (EOs) of Thymus algeriensis, Eucalyptus globulus and Rosmarinus officinalis from Morocco. RESULTS: The composition of these species was analysed by GC‐MS, and 65 components were identified. Eucalyptus globulus EO showed a great similarity with EOs from other regions, with 1,8‐cineole (79.85%) the major component. Also rich in this constituent was Rosmarinus officinalis (43.99%). However, the chemical profile of Thymus algeriensis was rather different, and for the first time such a high content of borneol (23.48%) has been described in this EO. The antimicrobial activity of these species has also been studied against seven pathogenic and spoiling bacteria of significant importance. According to the results, Thymus algeriensis showed the best bacteriostatic and bactericidal effect, followed by Eucalyptus globulus and Rosmarinus officinalis. CONCLUSIONS: As far as we know this is the first time that minimum inhibitory and bactericidal concentration values have been reported for Eucalyptus globulus EO. Our data support the possible use of this EO as well as Thymus algeriensis EO, as potential natural agents in preservatives for food and pharmaceutical products. Copyright © 2011 Society of Chemical Industry     

植物精油在可食性抗菌膜中的应用

本文简要介绍了可食性抗菌膜的种类和抑菌机理,综述了近年来国内外植物精油的提取技术、化学成分、抑菌机理、植物精油对可食性抗菌膜性能的影响及其在食品保鲜上的应用的研究进展,并分析了植物精油应用在可食性抗菌膜上可能存在的问题,对其未来发展前景进行了展望。      

辛香料精油在食品保藏中的应用研究进展

文章综述了近年来国内外对于辛香料精油在抑菌方面的研究,以及在果蔬采后保藏及肉品保藏方面的应用性研究进展。辛香料精油对多种食源性致病细菌和真菌均具有很好的抑菌效果,是一种高效、安全的食品防腐剂来源。     

Citrus essential oils: Extraction,authentication and application in food preservation

Citrus EOs is an economic, eco-friendly and natural alternatives to chemical preservatives and other synthetic antioxidants, such as sodium nitrites, nitrates or benzoates, commonly utilized in food preservation. Citrus based EOs is obtained mainly from the peels of citrus fruits which are largely discarded as wastes and cause environmental problems. The extraction of citrus oils from the waste peels not only saves environment but can be used in various applications including food preservation. The present article presents elaborated viewpoints on the nature and chemical composition of different EOs present in main citrus varieties widely grown across the globe; extraction, characterization and authentication techniques/methods of the citrus EOs; and reviews the recent advances in the application of citrus EOs for the preservation of fruits, vegetables, meat, fish and processed food stuffs. The probable reaction mechanism of the EOs based thin films formation with biodegradable polymers is presented. Other formulation, viz., EOs microencapsulation incorporating biodegradable polymers, nanoemulsion coatings, spray applications and antibacterial action mechanism of the active compounds present in the EOs have been elaborated. Extensive research is required on overcoming the challenges regarding allergies and obtaining safer dosage limits. Shift towards greener technologies indicate optimistic future towards safer utilization of citrus based EOs in food preservation.     

植物精油对真菌微生物抑制作用的研究进展

随着消费者对绿色产品的要求越来越高,人们开始考虑用天然植物精油作为抑菌剂代替化学合成杀菌剂.精油是从植物中分离的天然杀菌剂,具有对抗多种病原微生物的活性,在抑制真菌病害和减少真菌毒素积累方面具有较好的功效,逐渐被广泛应用于食品防腐保鲜、化妆品、医药等领域.该文综述了不同植物精油的化学组成和抑菌作用,分析了植物精油的抑菌...     

Enteric methane production in lactating dairy cows with continuous feeding of essential oils or rotational feeding of essential oils and lauric acid

Rumen microbes can adapt to feed additives, which may make the decrease in enteric CH₄ production upon feeding an additive a transient response only. This study investigated alternate feeding of 2 CH₄ mitigating feed additives with a different mode of action on persistency of lowering CH₄ production compared with feeding a single additive over a period of 10 wk. Four pairs of cows were selected, and within pairs, cows were randomly assigned to either the control (AR-AR) or the alternating (AR-LA) concentrate treatment. The AR concentrate contained a blend of essential oils (Agolin Ruminant, Agolin SA, Bière, Switzerland; 0.17 g/kg of dry matter) and the LA concentrate contained lauric acid (C12:0; 65 g/kg of dry matter). A basal concentrate without Agolin Ruminant and lauric acid was fed during the pretreatment period (2 wk). Thereafter, the cows assigned to the AR-AR treatment received the AR concentrate during all 10 treatment weeks (5 periods of 2 wk each), whereas cows assigned to the AR-LA treatment received AR and LA concentrates rotated on a weekly basis. Methane emission was measured in climate respiration chambers during periods 1, 3, and 5. From period 3 onward, dry matter intake and milk protein concentration were reduced with the AR-LA treatment. Milk fat concentration was not affected, but the proportion of C12:0 in milk fat increased upon feeding C12:0. Molar proportions of acetate and propionate in rumen fluid were lower and higher, respectively, with the AR-LA than with the AR-AR treatment. Methane yield (g/kg of dry matter intake) and intensity (g/kg of fat- and protein-corrected milk yield) were not affected by treatment. Methane yield and intensity were significantly lower (12 and 11%, respectively) in period 1 compared with the pretreatment period, but no significant difference relative to pretreatment period was observed in period 3 (numerically 9 and 7% lower, respectively) and in period 5 (numerically 8 and 4% lower, respectively). Results indicate a transient decrease in CH₄ yield and intensity in time, but no improvement in extent or persistency of the decline in CH₄ due to rotational feeding of essential oils and C12:0 in lactating dairy cows.     

植物精油应用研究进展

植物精油是植物体内的次生代谢物质,化学组成较为复杂。在医学领域,植物精油在去痛、降压、消炎、提高免疫力、抗菌、保健等方面得到了广泛的应用。在害虫防治方面,植物精油具有对害虫生物活性很高,又不易产生抗药性,且对人畜毒性很小,不污染环境等优点,是一种很好的生物农药原料。在化妆品方面,植物精油被广泛的应用于香水、香皂、洗面奶、护肤露等各种化妆品。此外,植物精油在饲料和食品添加剂、胶黏剂、生态旅游等方面也有广泛的应用价值。     

Preferential solubilization behaviours and stability of some phenolic-bearing essential oils formulated in different microemulsion systems

The solubilization behaviour of a number of essential oils (EOs) containing volatile phenolic constituents was investigated in five different micellar solutions. These oils include clove bud (Eugenia caryophyllata), thyme (Thymus serpyllum) and oregano (Thymus capitatus). Ternary and pseudo‐ternary phase diagrams were constructed to assess the ability for microemulsion formation and dilutability of each system using non‐ionic surfactants. Results showed that Tween 20 (T20) was more suitable to solubilize these oils compared with Tween 80 (T80). Clove EO was found to be easily microemulsifiable compared with the other EOs, whereas oregano showed the least tendency to form a microemulsion. Particle sizes measured at different dilution lines ranged between 5.9 and 16.9 nm. The chemical composition of each EO was revealed by gas chromatography and was correlated with the observed solubilization behaviour. The presence of solubilization enhancers like poly‐ols and short‐chain alcohols improved solubilization of all EOs; however, establishment of new dilution lines was controlled by EO type. Physical stability assessment showed that all microemulsions were stable against alternate freeze/thaw cycles which extended for 1 week. On the contrary, each system showed different temperature sensitivity in the thermal stress assessment. The results of this investigation can be useful in fabrication of thermodynamically stable aqueous system carrying aromatic and bioactive phenolics for different applications in personal hygiene, cosmetic, fragrance and pharmaceutical products.     

天竺桂挥发油对小鼠的体外抗氧化作用研究

目的:通过提取天竺桂挥发油,对小鼠进行体外的抗氧化的实验,研究天竺桂挥发油的抗氧化作用。方法:使用ROS测定试剂盒测定挥发油的抗活性氧能力;使用丙二醛(MDA)测定试剂盒和GSH-Px活力测定试剂盒测定天竺桂挥发油对小鼠体外MDA含量的影响;用分光光度法来测定天竺桂挥发油对H2O2所诱导的小鼠红细胞溶血和Fe2+-Vc诱导的肝线粒体肿胀度的抑制效果;通过化学方法考查了天竺桂挥发油清除DPPH自由基以及羟自由基的能力。结果:挥发油在浓度为0.25%～1.00%的范围内,有较强的体外抗氧化性,且能减少小鼠肝匀浆和心脏匀浆MDA的含量,对H2O2诱导的小鼠红细胞溶血和由Fe2+-Vc诱导的肝线粒体肿胀度均具有显著的抑制作用,具有较强的清除DPPH自由基以及羟自由基的能力。     

Analysis of essential oils from chemotypes of Thymus vulgaris in Catalonia

Essential oils from aerial parts of Thymus vulgaris have been obtained by hydrodistillation. Their components have been identified by gas chromatography/mass spectrometry. Samples were collected in Catalonia (northeastern Iberian peninsula), specifically in four locations along the Llobregat river basin. Such locations have different altitudes with respect to sea level (1500 m; 700 m; 300 m; 100 m), and have differences in pluvial regime and mean temperature. At 700 m, samples were collected from a transplanted specimen from 1500 m, in order to check the influence of the change in environmental conditions. Two different chemotypes have been characterized. Samples collected at 300 m have a dominant chemotype 1,8‐cineole, with 20% (approx.) essential oil content. The other samples have linalool as dominant chemotype with a 40–70% content, according to vegetative stage. Copyright © 2007 Society of Chemical Industry     

New and unexpected cosmetic properties of perfumes. Effects upon free radicals and enzymes induced by essential oils, absolutes and fragrant compounds

The biological properties of several different perfume components have been investigated. It has been demonstrated, through appropriate test methods, that essential oils, absolutes and even compounds show significant (anti/pro)-radical, (anti/pro)-elastasic and (anti/pro)-tyrosinasic activities. These unexpected properties open up new opportunities for the formulation of cosmetic products and could contribute to the understanding of activities traditionally attributed to essential oils by Aromatherapy.     

Lavender,tea tree and lemon oils as antimicrobials in washing liquids and soft body balms

The aim of this study was to evaluate the antimicrobial activity of commercial essential oils: lavender, tea tree and lemon, antimicrobials in washing liquid and O/W soft body balm. The inhibition efficacy of essential oils in washing liquid (1% alone or in mixtures), in soft body balm (0.5% alone), as well as combined with the synthetic preservative DMDM hydantoin and 3‐iodo‐2‐propynyl butyl carbamate mixture (0.1 and 0.3%), was tested against S. aureus ATCC 6538, P. aeruginosa ATCC 9027, Candida sp. ?OCK 0008 and A. niger ATCC 16404 in compliance with the European Pharmacopoeia standards. The components of the system preserving soft body balm were supplemented with a solubilizer. Washing liquids containing only essential oils met Criterion A E.P. only for S. aureus, Candida sp. and A. niger. In soft body balm formulations, oils at a concentration of 0.5% did not reveal any preserving activity. The introduction of a solubilizer to a system containing 0.5% tea tree oil led to a substantial increase in the bacteriostatic activity of the formulation, but did not significantly affect its fungistatic properties. A combination of 0.5% tea tree oil, 5% solubilizer and 0.3% synthetic preservative ensured the microbiological stability of soft body balm in accordance with Criterion A E.P.     

Biosynthesis of essential oils in aromatic plants: A review

In aromatic plants species, biosynthesis of essential oils occurs through two complex natural biochemical pathways involving different enzymatic reactions. Isopentenyl diphosphate (IPP) and its isomer dimethylallyl diphosphate (DMAPP) are the universal precursors of essential oil biosynthesis and are produced by the cytosolic enzymatic MVA (mevalonic acid) pathway or by plastidic and enzymatic 1-deoxy-d-xylolose-5-phosphate (DXP) pathway, also called the 2-C-methylerythritol-4-phosphate (MEP) pathway. In the particular plant cell part, prenyl diphosphate synthases condense isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP) further to form prenyl diphosphates, which are used as substrates for geranyl diphosphate (GPP; C₁₀) or for fernesyl diphosphate (FPP; C₁₅). Essential oils are final terpenoid products and are formed by a huge group of enzymes known as terpene synthases (TPS). Essential oils are important secondary metabolites of plants and have been used not only in different industries but also in ethnobotanical medicines for centuries. Hence, considerable research has been undertaken to understand the essential oil biosynthetic pathways. This review will be a valuable source of information in the field of natural products, as we give detailed insights about biosynthesis of essential oils in plants and thus indicate also new unexplored horizons for further research.     

Natural essential oils as reducing agents of peroxidase activity in leafy vegetables

The effectiveness of natural essential oils eucalyptus (Eucalyptus globulus), tea tree (Melaleuca alternifolia), melisa (Melissa officinalis), roomer (Rosmarinus officinalis), clove (Syzygium aromaticum) and lemon (Citrus limonum) to reduce peroxidase activity of organic leafy vegetables extracts was evaluated. Three oil concentrations at the minimum inhibitory concentration (MIC, 2×MIC and 4×MIC) of each natural essential oils were used. Crude vegetable extracts of Swiss chard, spinach, lettuce, butter lettuce and cabbage were the source of peroxidase activity. The effectiveness of the essential oils as natural antioxidants varied with the enzyme sources. At the MIC, clove, rosemary, lemon, melisa and tea tree had the high antioxidant properties being clove more effective than the other oils.     

几种香辛料精油对产气荚膜梭菌的体外抑菌效果

研究白芷精油、黑胡椒精油、茴香精油、肉桂精油、姜精油和艾草精油对产气荚膜梭菌（Clostridium perfringens,C.perfringens）的抑制作用,筛选出对产气荚膜梭菌有抑菌效果的香辛料精油。采用牛津杯法和两倍稀释法分别判定不同香辛料精油对C.perfringens（ATCC13124、CICC22949、C₁和C₂）的抑菌圈大小和最小抑菌浓度（Minimum inhibitory concentration,MIC）。结果显示:肉桂精油对C.perfringens的抑菌圈直径最大,且对产气荚膜梭菌ATCC13124、CICC22949、C₁和C₂的MIC分别为2.75、2.75、5.5、2.75 mg/m L;艾草精油对C.perfringens的MIC分别为11、2.75、11、2.75 mg/m L;黑胡椒精油对C.perfringens的MIC分别为22、11、11、5.5 mg/m L;茴香精油对C.perfringens的MIC分别为11、5.5、11、2.75 mg/m L;姜精油对C.perfringens的MIC分别为88、22、22、22 mg/m L。结论:除白芷精油以外,其他5种香辛料精油对C.perfringens均有不同程度的抑菌作用,其中肉桂精油对C.perfringens的抑菌效果最佳。      

Identification by epr spectroscopy of carvacrol and thymol as the major sources of free radicals in the oxidation of plant essential oils

The formation of stable free radicals upon reaction of the essential oils of 10 plant species with ultraviolet radiation and the superoxide radical anion, O₂^?, has been investigated by electron paramagnetic resonance (EPR) spectroscopy. Only the oils from oregano, summer savory and thyme produced EPR spectra and the results can be accounted for in terms of free radicals produced by the closely related phenolics, carvacrol and thymol. These observations are interpreted in terms of the known antioxidant properties of these molecules.     

Fragrance raw materials and essential oils can reduce prostaglandin E(2) formation in keratinocytes and reconstituted human epidermis

Essential oils and certain perfumery raw materials exhibit a wide range of beneficial biological activities. Besides the antimicrobial and antioxidant activity, the anti-inflammatory and anti-irritant effects are most often cited. One specific mode of action is the reduction of the formation of the key mediator prostaglandin E(2) (PGE(2)). To study this activity in detail and to create cosmetically useful fragrances with the potential to reduce a key marker of skin irritancy in keratinocytes, an initial screening with pig blood platelets was conducted on 900 perfumery raw materials. Active compounds were then validated in a human keratinocyte cell line. Compounds which successfully reduced PGE(2) formation in this assay were used for the creation of active fragrances. These final fragrances reduced PGE(2) formation by >80% when dosed at 0.8 mug mL(-1) to keratinocytes. Application of such a fragrance in a hydrogel allowed reduction of UVB-induced PGE(2) formation in reconstituted epidermis (MatTec EpiDerm(TM)). Similarly, antiperspirant-induced formation of PGE(2) in reconstituted epidermis was reduced to background levels if these novel fragrances were used in the antiperspirant formulation. In conclusion, fragrances with this added cosmetic benefit can be created based on a database from a comprehensive screening. These fragrances may find use as a part of a formulation strategy optimizing each part of a cosmetic formulation for optimal product mildness.