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1.
The synbiotic ability of probiotic bacteria and konjac glucomannan hydrolysates (GMH) to inhibit acne‐inducing bacterium, Propionibacterium acnes growth was studied in vitro. All probiotic bacteria strains tested were able to inhibit the growth of this species of skin bacterium where the inhibition was significantly (P < 0.01) enhanced by the presence of the GMH prebiotic. As the current treatment of acne is based on topical or systemic drugs, it is worth examining further the biotherapeutic activities of the GMH and selected probiotics with a view to future use as prophylactic or therapeutic synbiotics for treating acne infections.  相似文献   

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The influence of drying on the aroma compounds, from a chemical and sensory standpoint, and on the structural integrity of basil (Ocimum basilicum L) was evaluated. The drying methods tested were oven drying at 45 °C, air drying at room temperature and freeze‐drying. The volatile compounds of fresh and dried basil were extracted and concentrated by simultaneous distillation/extraction and analysed by gas chromatography/mass spectrometry. In all, 27 volatile components were identified, linalool being the major component, followed by eugenol. The total quantity of volatiles of fresh basil decreased considerably during oven drying and freeze‐drying, whereas air drying of basil at room temperature brought about only small losses of volatile components. The cell damage produced on basil leaves during drying was evaluated by scanning electron microscopy. From a sensory standpoint, fresh basil was described as having a fresh, herbaceous and floral odour, while the dried samples had a mentholated, spicy, hay‐like and earthy odour. Copyright © 2004 Society of Chemical Industry  相似文献   

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该研究考察SO3微热爆(SO3 Micro-Thermal Explosion,STEX)预处理辅助提取泰国罗勒挥发油的工艺,并对所得挥发油化学成分和香气轮廓进行比较分析。结果表明:阴干和SD(水上蒸馏)法是最优的干燥方式和提取方法;STEX预处理的最佳工艺为SO3与干物质质量比1:3、预处理温度50 ℃、预处理时间30 min,此条件下挥发油得率为0.56%,相比于SD法和WD(水中蒸馏)法分别提高了41.41%和90.48%;放大验证实验中挥发油得率可进一步提高至0.60%;扫描电镜观察发现STEX预处理后的罗勒表面微观结构发生明显改变,表面皱缩严重,气孔扩张明显;元素和红外分析结果显示,STEX预处理会显著提高罗勒S元素含量(p<0.05),但不影响其化学官能团构成;经GC-MS鉴定,WD、SD和STEX-SD来源的挥发油均以甲基胡椒酚和甲基丁香酚为主,其中,STEX-SD来源的挥发油可鉴定化合物31种,种类最多;感官评价结果表明,三种挥发油均以茴香和柠檬香为主,但STEX-SD来源的挥发油具有更明显的香气。STEX可作为一种预处理方法用于提高罗勒等芳香性植物挥发油的得率和香气品质。  相似文献   

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Lipids are important constituents of the human epidermis. Either free and organized into broad lipid bilayers in the intercorneocytes spaces, or covalently bound to the corneocyte envelope, they play a crucial role in permeability barrier function and are major contributors to cutaneous anti-microbial defense. Free sphingoid bases are a recent addition to this family of active lipids, which emerged from studies of breakdown products from ceramides. Phytosphingosine (PS) is a lipid occurring naturally in the stratum corneum, both in its free form and as a part of the major fraction of ceramides. The biotechnological production of PS patented by Degussa yields to PS with the correct configuration present in the skin. So, application of a PS containing formulation leads to its integration into the natural lipid structures of the skin. In acne, different pathogenetic factors contribute to the inflammation process, defect in keratinization, increased sebaceous gland activity and increased colonization of Propionibacterium acnes. The results of in vitro and in vivo studies confirm the previous reports on strong anti-microbial effectiveness of skin-identical PS produced by Degussa in vitro and in vivo. In addition, PS shows excellent clinical results in the context of skin care in acne, based on both anti-inflammatory and anti-microbial activity. These results demonstrate the potential of PS to enhance or complement existing acne therapies acting as an active cosmetic ingredient.  相似文献   

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研究了在分批发酵过程中补加氨水对1株薛氏丙酸杆菌(Propionibacterium shermanii)发酵及其代谢物对恶臭假单胞菌(Pseudomonas pudia)抑菌活性的影响。结果表明,薛氏丙酸杆菌代谢物在初始pH7.0时抑菌活性最高,为7.59AU/mL,显著高于其他实验组(p<0.05);每隔24h补加10%氨水溶液调节发酵液pH6.0时,薛氏丙酸杆菌的生物量和代谢物的抑菌活性都最大,分别为9.62mg/mL和16.42AU/mL;研究分别从第2、3或4d补加10%氨水开始调节发酵液pH6.0时发现,从发酵第2d开始调节pH效果最好,生物量和代谢物的抑菌活性分别达到9.55mg/mL和16.47AU/mL。这些结果表明,在分批发酵过程中补加氨水调节发酵液的pH可以显著提高丙酸杆菌代谢物的抑菌活性。   相似文献   

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Several tropical flowers have distinctive fragrances which are very appealing to use in perfumery, cosmetics and spa. However, to obtain a ‘natural fragrance’ from the flower is a challenge as the scent could change during the extraction process. The aim of the study is to find the suitable procedure for extraction of volatile oils from some Thai fragrant flowers. Three different methods: hydrodistillation, solvent extraction and enfleurage methods have been applied for the extraction of volatile oil from Jasminum sambac L. Aiton; Oleaceae (jasmine). The quantities and quality of jasmine volatile oils obtained from the different tested methods were compared. The solvent extraction method using 95% ethanol provided the greatest level of oil yield. However, sensory evaluation using preference test showed that the scents of the volatile oils from solvent extraction using diethyl ether and from enfleurage method were the closest to the fresh flowers compared with the volatile oils obtained from other methods. Their chemical constituents were analysed using gas chromatography coupled with mass spectrometer. Both volatile oils were then evaluated using a triangle discrimination test. From the triangle test, we found that 14 panellists from the total of 36 could not distinguish between the scents of jasmine oil from enfleurage and fresh jasmine flowers whereas only one panellist could not distinguish between the scent of jasmine oil from the solvent extraction and fresh jasmine flowers. These results suggest that the scent of the volatile oil obtained from the enfleurage method was the closest to fresh flowers compared with that obtained from other methods. This method was then successfully applied for extraction of volatile oils from three other Thai fragrant flowers, Michelia alba DC.; Magnoliaceae, Millingtonia hortensis L.; Bignoniaceae and Hedychium coronarium J. Konig; Zingiberaceae.  相似文献   

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The essential oils from dried leaves of Lavandula bipinnata (Roth) Kuntze (Lamiaceae), obtained by soxhlet extraction was analysed by gas chromatography–mass spectrometry (GC–MS) and was evaluated for in vitro antimicrobial activity. The most common components usually found in lavender essential oils were present in the oil samples analysed, out of 43 peaks, 29 components, which constitute 72.38%, were identified in the essential oil. The major constituents were transcarveol (18.93%), pulegone (8.45%), camphor (7.09%) and menthol (5.89%). Other constituents present in fairly good amounts are pipertone (4.65%), caryophyllene oxide (3.68%), linalyl acetate (3.37%) and bicyclogermacrene (3.09%). The essential oil was screened for antimicrobial activity by disc diffusion assay and minimum inhibitory concentration (MIC) against bacteria and fungus. Results reveal that L. bipinnata essential oils are inhibitory against the tested bacteria and fungal strains.  相似文献   

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The effects of basil (Ocimum basilicum L.) on soil organic matter biodegradation, nutritional mineral elements and bacterial colonies were studied in the laboratory. The air‐dried basil plant tissues incorporated at five different rates (0, 1, 2, 3, and 4 g per 50 g of soil) resulted in increases in organic carbon mineralization, mineral nitrogen forms in organic phosphorus and available potassium. The level of available forms of manganese and zinc was increased at all the rates of added basil whereas copper was increased at the two upper rates. Also, the addition of basil resulted in a decrease in soil bacterial colonies. The results of this study indicated that the basil could be used as a cover crop for suppressing weed or pathogens in organic soils, with a positive effect on soil productivity. In addition, the incorporation of basil in soil could reduce the number of bacterial colonies. Copyright © 2007 Society of Chemical Industry  相似文献   

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As part of ongoing research on Tanzanian plants used as edibles or spices, six samples of essential oils from four Ocimum species (O. basilicum, O. kilimandscharicum, O. lamiifolium, O. suave) were analyzed by GC and GC–MS. Eighty-one compounds, corresponding to 81.1–98.2% of the chemical components of the oils, were identified. Major compounds were either phenyl propane derivatives or terpenoids, including methyl eugenol, 1,8-cineole, camphor, bornyl acetate, germacrene-D, E-myroxide, germacrene-B, caryophylene oxide and p-cymene. The oils were also evaluated for antimicrobial activity against eight bacterial strains and three fungi. The oil of O. suave (B) showed the strongest antibacterial activity; O. suave (A), O. kilimandscharicum and, O. lamiifolium were moderately active, while O. basilicum oil was weakly active. However, none of the oils was active against the fungi species. The study has shown that, Ocimum oils could potentially be used as anti-infective agents.  相似文献   

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Essential oils, distilled from seeds of Coriander sativum and Carum carvii and from leaves of five different varieties of Ocimum basilicum, were fractionated by column chromatography and tested in the laboratory for volatile toxicity against three stored rice pests (Sitophilus oryzae, Rhyzopertha dominica and Cryptolestes pusillus). The active fractions were analyzed by GC-MS. Coriander contained linalool (1617 ppm of the oil) as the main product active against the three pests. Camphor-rich fractions (over 400 ppm) were very toxic to R. dominica and C. pusillus. The caraway profile included carvone and limonene as expected but (E)-anethole, generally regarded as a minor product in the essential oil of this species, was also a major component, being present at 365 ppm. Carvone was the most effective (972 ppm) monoterpenoid against S. oryzae. In addition, (E)-anethole at 880 ppm was toxic to R. dominica while vapors of limonene (1416 ppm) and fenchone-rich (554 ppm) fractions killed adults of C. pusillus only. Three major essential oil profiles were present in the five varieties of O. basilicum analyzed: methyl eugenol/estragole, estragole and estragole/linalool chemotypes. The abundance of components had a strong influence on the outcome of the bioassays. Fractions, where combinations of products occurred with or without other minor compounds, were often more toxic than any one compound alone.  相似文献   

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Antimicrobial activity of garlic (Allium sativum L.) and holy basil (Ocimum sanctum L.) essential oils (GEO and HBEO, respectively) was evaluated in liquid vs. vapour phases. Diallyl disulphide and diallyl trisulphide in GEO while eugenol, caryophyllene and methyl eugenol in HBEO were predominant active compounds. Individually, GEO was highly effective in the vapour phase, showing the greatest antimicrobial activity (P ≤ 0.05) against Bacillus cereus and Staphylococcus aureus with complete inhibition, followed by Salmonella typhimurium and Pseudomonas fluorescens, but had no effect on Escherichia coli, Lactobacillus plantarum or Listeria monocytogenes. The combined GEO:HBEO (a 1:1 ratio) at 30 μL demonstrated inhibitive activity against all bacteria tested with complete inhibition against Bcereus and Saureus. Minimum bactericidal concentration (MBC) of the combined oil was <0.4% v/v, except for Pfluorescens requiring a higher MBC (1.5%, v/v). This study demonstrated potential of the combined GEO:HBEO to be used for food preservation applications.  相似文献   

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Spices and herbal plant species have been recognized to possess a broad spectrum of active constituents that exhibit antimicrobial (AM) activity. These active compounds are produced as secondary metabolites associated with the volatile essential oil (EO) fraction of these plants. A wide range of AM agents derived from EOs have the potential to be used in AM packaging systems which is one of the promising forms of active packaging systems aimed at protecting food products from microbial contamination. Many studies have evaluated the AM activity of synthetic AM and/or natural AM agents incorporated into packaging materials and have demonstrated effective AM activity by controlling the growth of microorganisms. This review examines the more common synthetic and natural AM agents incorporated into or coated onto synthetic packaging films for AM packaging applications. The focus is on the widely studied herb varieties including basil, oregano, and thyme and their EOs.  相似文献   

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The essential oils from the dried leaves, pseudostems and rhizomes of Alpinia conchigera Griff. (KL 5049), collected from Jeli province of Kelantan, east coast of Peninsular Malaysia, were isolated by hydrodistillation. The collected oils were analyzed by capillary GC and GC–MS. Forty one compounds were identified, among which 13 have not been detected previously. The leaf, pseudostem and rhizome oils afforded 40, 33 and 39 constituents, respectively. The most abundant components in the leaf oil included β-bisabolene (15.3%), β-pinene (8.2%), β-sesquiphellandrene (7.6%), chavicol (7.5%) and β-elemene (6.0%), while β-bisabolene (19.9%), β-sesquiphellandrene (11.3%), β-caryophyllene (8.8%) and β-elemene (4.7%) were the main components in the pseudostem. In the rhizome, 1,8-cineole (17.9%), β-bisabolene (13.9%), β-sesquiphellandrene (6.8%) and β-elemene (4.0%) were the major components. The essential oils were also subjected to antifungal and antibacterial tests, using the minimum inhibitory concentration (MIC) method. Results revealed weak inhibitions against the microorganisms tested.  相似文献   

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