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用抑菌圈法考察了田基黄总黄酮浓度、pH和处理温度对大肠杆菌、枯草芽孢杆菌、金黄色葡萄球菌的抑菌活性.结果表明,总黄酮提取物对大肠杆菌、枯草芽孢杆菌和金黄色葡萄球菌都具有良好的抑菌活性,最小抑菌浓度分别为3.125,6.25,1.562 5 μg/mL.总黄酮浓度为12.5 μg/mL的田基黄提取物对大肠杆菌、金黄色葡萄球菌和枯草芽孢杆菌分别在pH为8,7~8和5抑菌活性最大.总黄酮提取液具有较强的耐热性能,在20℃和80℃加热处理30 min后对大肠杆菌、枯草芽孢杆菌和金黄色葡萄球菌的抑菌圈分别为12.8,10.2,11.3 mm和12.0,10.0,10.8 mm. 相似文献
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为解决单一植物精油在抗菌应用时,用量相对较大、气味单一且浓郁刺激、易引起人们感官不适及过敏反应等问题。通过研究13种单一植物精油对大肠杆菌和金黄色葡萄球菌的抑菌效果,以山苍子精油为基调,采用棋盘稀释法、抑菌圈法、感官评价等方法筛选出具有协同抗菌效果的芳香复配精油,并以大肠杆菌为供试菌探究了其抑菌机理。结果表明,当V(山苍子精油) ∶V(肉桂精油)=2∶1时制备的复配精油对大肠杆菌和金黄色葡萄球菌具有优异的协同抗菌性,抑菌圈直径分别为(21.12±0.17)mm和(40.26±0.61)mm,且香气较愉悦、舒适、易接受。与单一山苍子精油和肉桂精油相比,复配精油对大肠杆菌的抑制效果更为明显,且可以破坏菌体细胞膜,影响细胞膜通透性,导致细胞内离子、核酸等成分泄露,使得菌液相对电导率明显增加,细菌细胞内容物泄露程度与单一山苍子精油和肉桂精油相比分别提升140%和20%。 相似文献
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为解决单一植物精油在抗菌应用时用量相对较大、气味单一且浓郁刺激、易引起人们感官不适及过敏反应等问题。通过研究13种单一植物精油对大肠杆菌和金黄色葡萄球菌的抑菌效果,以山苍子精油为基调,采用棋盘稀释法、抑菌圈法、感官评价法筛选出具有协同抗菌效果的芳香复配精油,并以大肠杆菌为供试菌探究了其抑菌机理。结果表明,当V(山苍子精油)∶V(肉桂精油)=2∶1时制备的复配精油对大肠杆菌和金黄色葡萄球菌具有优异的协同抗菌性,抑菌圈直径分别为(21.12±0.17)和(40.26±0.61)mm,且香气较愉悦、舒适、易接受。与单一山苍子精油和肉桂精油相比,复配精油对大肠杆菌的抑制效果更为明显,且可以破坏菌体细胞膜,影响细胞膜通透性,导致细胞内离子、核酸等成分泄漏,使菌液相对电导率明显增加,细菌细胞内容物泄漏程度与单一山苍子精油和肉桂精油相比分别提升140%和20%。 相似文献
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利用气相色谱-质谱法分析了毛竹和日本花柏精油的活性化学成分,结果表明:毛竹精油主要化学成分为柏木醇(44.03%)、罗汉柏烯(13.88%)、花侧柏烯(11.48%)、马兜铃烯(4.82%)和α-杜松醇(3.66%);日本花柏精油主要化学成分为δ-杜松醇(35.04%)、α-杜松醇(14.40%)、epi-双环倍半水芹烯(10.08%)、可巴烯(9.84%)、8-丙氧基-香松烷(7.84%)、卡达烯(3.60%)和γ-桉叶醇(3.41%)。α-杜松醇、罗汉柏烯和马兜铃烯是毛竹和日本花柏精油的共有化学成分,柏木醇和α-杜松醇是具有开发潜力的活性化学成分。 相似文献
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The essential oils in Phoebe hui Cheng ex Yang were extracted from its roots, trunk, bark, branches, and leaves by a hydrothermal method and then analyzed by gas chromatography–mass spectrometry. The essential oils extracted from the xylem of the roots and trunks of this species had similar chemical constituents (primarily α-bergamotene, calarene, 3,7-guaiadiene, β-sesquiphellandrene, β-farnesene, β-bisabolene, torreyol, and τ-muurolol) in similar quantities. Meanwhile, the main chemical constituents of the essential oil extracted from the xylem of this species were considerably different from those extracted from Phoebe zhennan. Hence, analysis of the oils extracted from the xylem can be used to distinguish between these species. The essential oils extracted from the bark, branches, and leaves of P. hui Cheng ex Yang had identical chemical constituents. The bark oil comprised mainly cubebene, α-muurolene, δ-cadinene, cadina-1,4-diene, guaiol, δ-cadinol, and α-cadinol, whereas the branch oil mainly included cubebene, α-selinene, δ-cadinene, cadina-1,4-diene, guaiol, δ-cadinol, and α-cadinol. The leaf oil extract consisted of cyclosativene, γ-muurolene, β-selinene, α-selinene, γ-cadinene, δ-cadinene, δ-cadinol, γ-eudesmol, α-cadinol, β-eudesmol, and α-eudesmol. Although the antimicrobial effects of the essential oils extracted from the individual tree parts were unclear, a mixture of these oils exhibited significant antitumor properties. 相似文献
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三种理气类中药挥发性成分的GC-MS分析 总被引:2,自引:0,他引:2
研究了三种(厚朴、檀香、木香)理气类中药挥发油的化学成分。用水蒸气蒸馏提取三种药材的挥发油,用GC-MS分离检测其化学成分,并结合气相色谱程序升温指数辅助定性确定出挥发油中的化学组分。鉴定出木香挥发油中29个成分(占挥发油总量的92.00%);厚朴挥发油中26个成分(占挥发油总量的91.88%);檀香挥发油中10个成分(占挥发油总量的94.51%),三中药物挥发油的主要成分大不相同。计算了各种化合物的保留指数,使用保留指数辅助定性鉴定出的化合物所占挥发油百分含量明显多于文献中所报道的数据。 相似文献
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亚临界水提取干花椒中精油的研究 总被引:3,自引:0,他引:3
采用亚临界水提取技术从干花椒中提取花椒精油.考察了原料颗粒度、提取时间、提取温度等因素对花椒精油提取得率的影响.确定亚临界水提取花椒精油的最佳工艺为:原料颗粒度0.5 mm、提取时间40 min、100~150℃的连续程序升温、压力5 Mpa,在此条件下花椒精油的提取得率为5.42%.同时,对亚临界水提取所得的花椒精油进行了抗氧化实验,并与常用抗氧化剂BHT和BHA进行了对比.结果表明,亚临界水提取所得的花椒精油具有较好的抗氧化性.用亚临界水提取技术提取花椒精油具有效率高、能耗低的优点. 相似文献
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Nancy Larocque C. Vincent A. Bélanger J.-P. Bourassa 《Journal of chemical ecology》1999,25(6):1319-1330
The formulations TSW (tansy essential oil, surfactant, distilled water) and TSWD (tansy essential oil, surfactant, distilled water, dillapiol) increased the feeding rate of oblique-banded leafroller (OBLR) larvae with increasing concentrations of tansy essential oil. When tansy essential oil was continuously present at 0.1% and 1% in the diet, all OBLR larvae from susceptible and resistant populations died. The presence of 0.01% tansy essential oil in the diet affected female pupal weight, but not larval weight gain, larval developmental time and male pupal weight. Our results suggest that the concentration of tansy essential oil that significantly affects the developmental variables should be between 0.01% and 0.1% of tansy essential oil. Residues of the formulation TE (tansy essential oil, ethanol 95%) deterred oviposition of OBLR female. 相似文献
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重庆含笑鲜花挥发油的化学成分分析 总被引:2,自引:1,他引:1
采用水蒸气蒸馏法(SD)和同时蒸馏萃取法(SDE)分别提取了重庆地区含笑鲜花的挥发油,并用气相色谱-质谱联用技术对其挥发油的化学成分进行了分离鉴定。从含笑鲜花水蒸气蒸馏和同时蒸馏萃取所得挥发油中,分别鉴定出38种和36种化合物,分别占挥发油色谱总峰面积的92.928%和90.555%。两种方法提取的含笑鲜花挥发油提取率分别为0.12%和0.26%,主要成分均为萜烯类、萜烯醇类、酯类化合物,相对质量分数较高的成分有τ-榄香烯、石竹烯、β-榄香烯、大根香叶烯D、α-布藜烯、(Z)-5,11,14,17-二十碳四烯酸甲酯等。 相似文献
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19世纪末到20世纪的工业革命期间,随着电力、石油、汽车等工业的发展,人类对能源的使用和消耗以指数速度迅速增长。能源开采、生产及使用等行为导致全球气候变暖、资源匮乏,人类的健康和生存受到威胁。保护环境、节省资源、开发新能源便成为现代工业发展以及人类生产生活的核心,而提高效率、减少污染,再生、再利用及持续性发展则成为发展的主要驱动力。过滤分离作为一种低能耗技术过程,近年来其应用领域在能源、资源及环境方面得到深广的发展,而其自身产品技术则同时得到日新月异的发展。其发展趋势体现在高能效、低能耗、自动、连续、更高的分离精度,更广的温度压力适用范围,更长的使用寿命以及更低的对环境的影响。本文围绕环境、资源、能源等方面现在及未来的应用需求,重点介绍欧美近年来过滤分离在如页岩天然气开采中的采出水处理,生物柴油、生物甲烷等可再生能源,水处理,工业废气、汽车尾气及室内空气过滤等方面的新技术新产品,以及传统过滤分离技术的新应用,并对过程计算模拟的发展应用及过滤分离基础理论研究状况做了简略介绍。 相似文献
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Huey-Chun Huang Hsiao-Fen Wang Kuang-Hway Yih Long-Zen Chang Tsong-Min Chang 《International journal of molecular sciences》2012,13(11):14679-14697
The study was aimed at investigating the antimelanogenic and antioxidant properties of essential oil when extracted from the leaves of Artemisia argyi, then analyzing the chemical composition of the essential oil. The inhibitory effect of the essential oil on melanogenesis was evaluated by a mushroom tyrosinase activity assay and B16F10 melanoma cell model. The antioxidant capacity of the essential oil was assayed by spectrophotometric analysis, and the volatile chemical composition of the essential oil was analyzed with gas chromatography-mass spectrometry (GC/MS). The results revealed that the essential oil significantly inhibits mushroom tyrosinase activity (IC50 = 19.16 mg/mL), down-regulates B16F10 intracellular tyrosinase activity and decreases the amount of melanin content in a dose-dependent pattern. Furthermore, the essential oil significantly scavenged 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and 2,2′-azino-bis (3-ethylbenzthiazoline- 6-sulphonic acid) ABTS radicals, showed an apparent reduction power as compared with metal-ion chelating activities. The chemicals constituents in the essential oil are ether (23.66%), alcohols (16.72%), sesquiterpenes (15.21%), esters (11.78%), monoterpenes (11.63%), ketones (6.09%), aromatic compounds (5.01%), and account for a 90.10% analysis of its chemical composition. It is predicted that eucalyptol and the other constituents, except for alcohols, in the essential oil may contribute to its antioxidant activities. The results indicated that essential oil extracted from A. argyi leaves decreased melanin production in B16F10 cells and showed potent antioxidant activity. The essential oil can thereby be applied as an inhibitor of melanogenesis and could also act as a natural antioxidant in skin care products. 相似文献