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1.
尿液在哺乳动物间的化学通讯中具有重要作用。本研究采用顶空固相微萃取-气质联用(HS-SPME-GC/MS)方法分析四川短尾鼩尿液中挥发性物质化学组成。结果表明,(1)通过检索国家标准与技术研究所质谱库,发现四川短尾鼩尿液中的化学成分主要为醛类、醇类、酮类、杂环、酯类、烷烃类、芳香烃类、含硫化合物、烯烃类、酚类等86种化合物,并且不同个体气味包含特有的挥发性化合物;(2)雌雄个体尿液中分别特有的挥发性化合物共计10种,其中雌性特有6种,雄性特有4种,表明四川短尾鼩尿液的化学成分存在性别差异。雌性的尿液中挥发性化合物76种,雄性只有33种,说明四川短尾鼩尿液中化学信号雌性多于雄性;(3)四川短尾鼩尿液中不同化学成分相对含量不同,同一组分在不同个体间相对含量存在差异。本研究有助于揭示四川短尾鼩尿液挥发性成分的化学通讯功能,并为引诱剂的研制提供基础资料。  相似文献   

2.
肠道益生菌体外抑菌活性的研究   总被引:4,自引:1,他引:3  
以6种常见肠道致病菌作为指示菌,研究了来自健康青年和儿童肠道的25株益生菌发酵浓缩液的体外抑菌效果.进一步研究了抑菌作用良好的LMa1和LMa3经pH调节、热处理、蛋白酶处理以及发酵过程中的抑菌活性变化.短链有机酸作为发酵终产物的主要成分之一,其抑菌效果也被测定.结果表明,抑菌物质包括短链有机酸(主要为乙酸和乳酸)和一类对热稳定、对部分蛋白酶敏感的物质,可能是某种细菌素.低pH是表现抑菌活性的必要条件,但仅有低pH(如低pH缓冲液)并无明显抑菌效果.  相似文献   

3.
本研究选用肉桂(Cinnamomum cassia)的桂皮、桂叶、桂枝、果实、花萼5种植物部位为研究对象,通过气质联用对各部位精油的主要成分组成进行了分析比较。在此基础上,从抑菌圈、最低抑菌浓度(MIC)、最低杀菌浓度(MBC)等方面比较各部位精油对金黄色葡萄球菌(Staphylococcus aureus)、大肠杆菌(Escherichia coli)抑制活性。结果表明,各部位精油中的主要成分均为反式肉桂醛、邻甲氧基肉桂醛等,但各成分的含量存在明显差异,以花萼中的反式肉桂醛含量最高(87.68%)。各部位精油对两种供试微生物均具有显著抑菌效果,以桂枝中所含精油的抑菌效果最佳,对E.coli和S.aureus的MIC分别为0.05%和0.025%,MBC同样也分别为0.05%和0.025%。  相似文献   

4.
壳聚糖抑菌机制的初步研究   总被引:4,自引:0,他引:4  
壳聚糖在医学、食品、环保、日化用品等领域有着广泛而重要的应用.近年来,壳聚糖由于对不同的菌类都具有良好的抑菌效果而被研究者们密切关注.然而,有关壳聚糖抑菌机制的研究却并不多,其抑菌机制也没有被完全阐明.在本研究中,我们发现很多金属离子可以对壳聚糖的抑菌效果产生影响,高浓度金属离子(0.5%)可以使壳聚糖完全丧失抑菌活性.还发现金黄色葡萄球菌和白色念珠菌在壳聚糖的作用下会发生钾离子和ATP的渗漏,而且五万分子量的壳聚糖引起钾离子和ATP的渗漏大约比五千分子量壳聚糖多2到4倍.不同分子量的壳聚糖对金黄色葡萄球菌和白色念珠菌都具有较好的抑菌效果,但是引起钾离子和ATP的渗漏量却存在很大差异,这说明小分子量壳聚糖很可能存在与大分子量壳聚糖不同的抑菌机制.  相似文献   

5.
为探究山苍子不同种之间化学成分及抑菌效果的差异,本研究通过生长速率法和抑菌圈法测定三种山苍子精油对尖孢镰刀菌、大肠杆菌和李斯特菌的抑菌活性,同时对三种山苍子精油进行GC-MS挥发性成分鉴定,进一步对精油主要化学成分与抑菌率进行相关性分析。结果表明,山鸡椒果实精油含量最高且对尖孢镰刀菌、大肠杆菌和李斯特菌的抑菌效果优于毛叶木姜子和毛山鸡椒;三种山苍子精油抑菌效率均与柠檬醛、芳樟醇的含量分别呈现显著正相关,提示主要成分柠檬醛含量适合作为山苍子优良精油筛选的可靠指标。研究结果为山苍子精油抗菌物质的开发利用提供了理论依据。  相似文献   

6.
柚子皮是一种富含精油的具有药用价值的生物质资源,但其精油成分与生物活性尚未深入研究。本文首先通过水蒸汽蒸馏法提取了12个不同品种的柚子皮精油,接着用气相色谱质谱联用仪(GC-MS)对精油成分与相对含量进行了测定,然后采用DPPH自由基清除法、滤纸片法对不同品种柚子皮精油的抗氧化和抑菌能力进行比较,最后对不同品种柚子皮精油GC-MS分析数据进行主成分分析和聚类分析,结合抗氧化和抑菌实验结果,着力于理清柚子皮精油成分与抗氧化、抑菌能力的关系。实验结果表明:柚子皮精油的提取率为0.22%~1.52%;GC-MS法从不同品种柚子皮精油中鉴定出D-柠檬烯、β-月桂烯、α-蒎烯、α-水芹烯、芳樟醇等35种化学成分;DPPH自由基清除实验表明柚子皮精油的抗氧化能力与精油浓度呈正相关性;滤纸片法抑菌实验表明柚子皮精油有一定的抑菌效果,且对特定的菌种抑菌效果更明显。主成分分析和聚类分析结果表明,抗氧化和抑菌效果显著的成分有D-柠檬烯、柠檬醛、芳樟醇,而石竹烯、香叶烯醇、α-水芹烯也具有一定的抗氧化和抑菌能力。  相似文献   

7.
对有柄石韦活性成分的抑菌作用做了初步探讨.以不同有柄石韦提取物作用于临床常见的8种病原菌,测定其半数抑菌浓度(IC50).结果证明有柄石韦不同粗提物对多种病原菌均有不同程度的抑制作用,其中黄酮类化合物抑菌效果尤为显著.  相似文献   

8.
目的:对苦豆籽中抑菌活性物质进行跟踪筛选。方法:采用溶剂萃取法获得苦豆籽不同极性溶剂萃取的浸膏,对其浸膏及实验室自制单体类化合物通过纸片扩散法(K-B)法进行抑菌试验研究。结果:苦豆籽粗提物对实验所用菌种都有不同程度的抑制作用,尤其是氯仿浸膏中可能含大量生物碱,因此表现出强的抑菌效果;苦豆籽单体类化合物对实验所用菌种都具有较强的抑制作用,苦参碱的抑菌效果最好。结论:苦豆籽中主要抑菌成分为生物碱类化合物,其中苦参碱的抑菌效果优于氧化苦参碱。  相似文献   

9.
杨梅果实不同溶剂提取物抑菌特性的研究   总被引:3,自引:1,他引:2  
目的探讨4种溶剂杨梅果实提取物对14种致病菌的抑菌作用,并对其中活性成分的含量进行测定和比较。方法利用常压浸提法制备杨梅果实的水、乙醇、乙酸乙酯和丙酮提取物;采用管碟法、琼脂平板稀释法测定各种杨梅提取物的抑菌活性,采用常规含量测定方法对各提取物中的主要成分及含量进行研究。结果4种杨梅果实提取物对革兰阴性和阳性菌均表现出了较强的抑菌活性,其中水提取物的抑菌活性最强。含量测定结果表明4种提取物的主要成分中总酚、黄酮含量以及总酸度相差较大,单宁含量差异较小。结论推测提取物中的主要抑菌成分为单宁类物质并确定杨梅果实的最佳提取溶剂为水。  相似文献   

10.
植物精油抑菌活性研究进展   总被引:8,自引:0,他引:8  
本文综述了国内外植物精油在农用抑菌活性及抑菌活性成分研究方面所取得的成果。阐述了具有农用抑菌活性的31种植物精油及其抑菌效果,并列举了植物精油中13种具有开发潜力的抑菌活性成分,简要分析了植物精油及其主要活性成分的作用机理。  相似文献   

11.
Myoglobin was isolated from the skeletal muscle of the water tortoise, Trionyx niloticus. The myoglobin is monomeric with an apparent molecular weight of 18,000 daltons as determined on Sephadex G-75 (with a non-denaturing eluant) and 18,547 from the amino acid composition. Spectrophotometric characteristics for a variety of ferrous and ferric derivatives have been determined.  相似文献   

12.
Treatment with phenobarbital causes an increased urinary excretion of tetrahydroxylated bile acids in patients suffering from intrahepatic cholestasis. The main components were isolated from urine by means of column and thin-layer chromatography and were studied as methyl esters by nuclear magnetic resonance spectroscopy. The results obtained strongly support the contention that the main components are 1 beta-, 6 alpha- and 6 beta-hydroxylated derivatives of cholic acid.  相似文献   

13.
桃儿七和南山荷叶内生真菌的生物活性研究   总被引:11,自引:0,他引:11  
通过研究桃儿七(Sinopodophyllum hexandrum)与南方山荷叶(Diphylleia sinensis)的内生真菌的生物活性,探讨内生真菌作为生物活性物质资源开发利用的价值。测定内生真菌发酵液的抗细菌、抗真菌、抗卤虫活性后,发现大多数菌株的发酵液都具有不同的生物活性。高活性菌株集中于镰孢霉属、柱孢属、木霉属、色串孢属。桃儿七内生真菌抗真菌活性较强,南方山荷叶内生真菌抗细菌和抗卤虫活性较强。桃儿七和南方山荷叶内生真菌是寻找有价值的活性成分的良好资源。  相似文献   

14.
The major lipid classes, their fatty acid profiles, and the amounts of the lipid‐soluble components, vitamin E, vitamin A, and carotenoids, were determined for egg yolks of the Hermann’s tortoise (Testudo hermanni boettgeri) with the aim of identifying any features that may potentially impair the adaptation of this endangered species to deteriorations in habitat. Total lipid formed 16% (wt/wt) of the fresh yolk and consisted of (wt/wt) 74.4% triacylglycerol, 18.1% phospholipid, 3.0% cholesteryl ester, and 3.4% free cholesterol. Despite a diet based on green plants, contributing α‐linolenic acid as the main polyunsaturate, this fatty acid formed only 3.8% of the total mass of fatty acid of the total lipid. The main acyl component of the yolk lipids was the monounsaturated fatty acid, oleic acid, which formed 45.6% of the total. The most striking feature of the yolk composition was the almost complete lack of two nutrients, docosahexaenoic acid and vitamin A, which are essential for the developing embryo. Although it is feasible that the embryo synthesizes docosahexaenoic acid from yolk‐derived α‐linolenic acid and also converts yolk‐derived β‐carotene to vitamin A, the yolk is poorly endowed with both these precursors. The stringencies displayed by the yolk composition in this species may limit the flexibility to adapt to changes in the availability of food items when the habitat is threatened. Zoo Biol 20:75–87, 2001. © 2001 Wiley‐Liss, Inc.  相似文献   

15.
<正>哺乳动物的尿液挥发性成分被认为是同哺乳动物信息激素一样重要的物质,迄今报道的野生动物尿液挥发性成分研究的有狮(Panthera leo)(Andersen and Vulpius,1999)、山猫(Lynx rufus)(Mattina et al.,1991)、土狼(Canis lupus)(Raymer et al.,1986)、郊狼(Canis latrans)(Schultz,1988)、红狐(Vulpes vulpe)(Jorgensen et al.,1978)以及鼬科物种(Zhang et al.,2005)。Robert和Joseph(1991)利用山猫和土狼尿液气味抑制白尾鹿(Odocoileus leucurus)对日本  相似文献   

16.
Depending upon preceding dietary exposure, the tortoise beetle, Cassida nebulosa L. (Coleoptera: Chrysomelidae), exhibits various feeding responses to spinach, Spinacia oleracea L. (Chenopodiaceae). Adult tortoise beetles reared as adults on the main host Chenopodium album var. centrorubrum Makino (CAC) (Chenopodiaceae) eat little spinach, whereas those reared on spinach accept this plant as food. In this study, we investigated the suppressive effect of exposure to CAC on the feeding response of tortoise beetles to spinach. To investigate the effect of chemical factors in CAC, we provided beetles with Gomphrena globosa L. (Amaranthaceae) as the base food and exposed them to a CAC extract, because bioassays have indicated that exposure to G. globosa did not affect the feeding response of beetles to spinach. Adults reared on G. globosa treated with CAC extract consumed significantly less than adults reared on untreated G. globosa . Thus, we determined that exposure to CAC components is responsible for the suppressive effect on the feeding response to spinach observed in the beetles. In a choice feeding test with membrane filter discs, we found that adults reared on G. globosa treated with CAC extract exhibited a greater feeding deterrent response to the spinach deterrent than adults reared on untreated G. globosa leaves. Therefore, the suppression of spinach consumption due to exposure to CAC is probably caused by the development of a response to the feeding deterrents present in spinach.  相似文献   

17.
New methods involving high-performance liquid chromatography/inductively coupled plasma mass spectrometry were examined for the determination of phenylarsenic compounds derived from chemical warfare agents. Several methods were examined for the separation of diphenylarsinic acid (DPAA), phenylarsonic acid, phenylmethylarsinic acid (PMAA), phenyldimethylarsine oxide, and diphenylmethylarsine oxide. Analysis of the urine samples of the patients exposed to phenylarsenic compounds indicated that the main phenylarsenic components were DPAA and PMAA; moreover, some unknown arsenicals, which were also found in contaminated groundwater and rice samples, were also detected.  相似文献   

18.
Recent studies from the author’s laboratory indicated that camel urine possesses antiplatelet activity and anti-cancer activity which is not present in bovine urine. The objective of this study is to compare the volatile and elemental components of bovine and camel urine using GC–MS and ICP–MS analysis. We are interested to know the component that performs these biological activities. The freeze dried urine was dissolved in dichloromethane and then derivatization process followed by using BSTFA for GC–MS analysis. Thirty different compounds were analyzed by the derivatization process in full scan mode. For ICP–MS analysis twenty eight important elements were analyzed in both bovine and camel urine. The results of GC–MS and ICP–MS analysis showed marked difference in the urinary metabolites. GC–MS evaluation of camel urine finds a lot of products of metabolism like benzene propanoic acid derivatives, fatty acid derivatives, amino acid derivatives, sugars, prostaglandins and canavanine. Several research reports reveal the metabolomics studies on camel urine but none of them completely reported the pharmacology related metabolomics. The present data of GC–MS suggest and support the previous studies and activities related to camel urine.  相似文献   

19.
旨在探究健康大鼠的尿液代谢物在生长、发育和衰老过程中的年龄相关性变化.采集大鼠出生后3周、5周、7周、9周、12周、56周和111周共7个年龄点的尿液样本,利用GC/TOF-MS平台进行代谢组学检测.结果显示,所有尿液样本在主成分分析与偏最小二乘法判别分析中出现组内聚类和组间分离.氨基酸类、有机酸类和碳水化合物类代谢物...  相似文献   

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