含笑精油抑菌活性研究及其化学成分分析-植物学专业论文.docxVIP

硕士学位论文 硕士学位论文 含笑精油抑菌活性研究及其化学成分分析 摘要 本文以优良园林树种含笑为原材料，以用水蒸气蒸馏法提取出的含 笑花精油和叶精油为研究对象，采用平板菌落法检测两种精油对供试细 菌的抑菌活性，通过滤纸片法测定两种精油对供试真菌的抑菌活性，采 用不同pH、温度及紫外线处理研究了含笑花精油和叶精油的抑菌稳定 性，通过气态防腐及其应用实验，测试了两种精油在气态氛围下对供试 细菌和空气中真菌的抑菌活性以及对新鲜猪肉和豆腐的保鲜作用，通过 气相色谱．质谱(GC．MS)联用技术分析了两种精油的化学成份。结果如 下： (1)含笑花精油和叶精油的抑菌活性 含笑花精油对枯草芽孢杆菌、大肠杆菌和总状毛霉抑制效果较佳， 抑菌率分别可达70．36％、60．24％、65．52％，对金黄色葡萄球菌、黄曲霉 具有一定的抑制效果，对米根霉无抑制效果；含笑叶精油对大肠杆菌、 金黄色葡萄球菌和枯草芽孢杆菌的抑菌效果很好，LCso值分别为： O．641．tL·mL‘1、O．771aL-mL一、0．62p,L·mL～，MIC值分别为：1 8．90l,tL·mL～、 20．109L·mL一、15．209L·mL-1．叶精油对总状毛霉、黄曲霉和米根霉的抑 菌效果较差，抑菌率达不到50％。 (2)含笑花精油和叶精油的抑菌稳定性 对两种精油通过不同pH、温度及紫外线照射时间的处理，来测定温 度和紫外线照射对精油抑菌活性的影响。结果显示两种精油的热稳定性、 紫外稳定性良好，这为含笑花精油和叶精油在工业上的利用提供参考。 (3)含笑花精油和叶精油的气态防腐及其应用 含笑花精油和叶精油在气态氛围下能够对供试细菌和空气中常见霉 菌具有一定的抑制活性，并且能够有效延长猪肉和豆腐的腐变期。 (4)含笑花精油和叶精油的化学成分 通过气相色谱．质谱(GC．MS)联用技术分析两种精油的化学成份，从 花精油中分离并鉴定出了30种化合物，从叶精油中分离并鉴定出了23 种化合物，确定了决定含笑花香型的6种酯类化合物，并初步分析了花 精油和叶精油的主要抑菌化合物。 关键词： 含笑；精油；抑菌：化学成分 0f 0f M．figo．The essential oils were extracted by steam distillation．The antimicrobial activities of the flowers and leaves essential oils on bacteria and fungi were tested with plate counts and filter paper methods．The antibacterial stabilities of the two essential oils were tested through di ffent pH，temperature and UV treatments．The antimicrobial activities of the essential oil s in gas condition on bacteria and fungi were tested，and gas antisepticise experiments to flesh pork and tofu were tested synchronously． At last，the chemical constituents of the flowers and the leaves essential oils were analyzed by GC．MS．The results were showed as follows： 1．The antimicrobial effect of the flowers essential oil on Bacillus s口btills、Escherichia coli and Mucor racemosus were fine，and their inhibitory rates were up to 70．36％、60．24％、65．52％．There were certain antimicrobial effect on Staphylococcus aureus and Aspergillus flavus，but no antimicrobial effect on Rhizopus oryzae． 2．The antimicrobial effect of the essential oil from the leaves on Escherichia coli，Staphylococcus aureus and Bacillus sabtills we