银杏叶黄酮的超声波提取及其抗菌研究

Studies on Ultrasonic-assisted Extraction and Anti-microbial Activities of Flavonoids from Ginkgo Leaves

利用超声波法提取银杏叶总黄酮,在单因素试验的基础上,采用正交试验对提取工艺进行了优化研究,并采用二倍稀释法进行了银杏叶黄酮对细菌(大肠杆菌、金黄色葡萄球菌)、霉菌(青霉菌、黑曲霉菌)及酵母(酿酒酵母)的抑菌试验。结果表明,银杏叶黄酮的最佳提取工艺为:乙醇体积分数70%,超声提取时间为50 min,液料比为30∶1;在该条件下银杏叶中黄酮提取率为3.51%;银杏叶黄酮对不同的菌种有不同的抗菌效果,对细菌有明显的抗菌作用,对霉菌的抗菌作用较弱,对酵母抗菌作用不明显。

On the basis of single factor test, the orthogonal design was employed to optimize ultrasonic-assisted extraction of total flavonoids from ginkgo leaves, anti-microbial activities of flavonoids from ginkgo leaves were evaluated against bacteria （Escherichia coli, Staphylococcus aureus ） , mold （Penicillium, Aspergillus niger）, as well as yeast （Saccharomyces cerevisiae） using the microdilution broth method. The results indicated that the highest extraction yield of flavonoids by ultrasonic-assisted extraction could obtain to be 3.51% using ethanol concentration of 70% （V/V） as solvent and liquid to solid ratio of 30：1 （mL/g） for 100 min. Anti-microbial effect offlavonoids from ginkgo leaves to the bacteria was obvious, but it was not so effective to yeast and mold.