湘西“蒿菜粑粑”原料植物鼠麴草总黄酮的提取及抑菌活性研究

Extraction and antibacterial activity of total flavonoids from Gnaphalium affine D.Don in Xiangxi

为研究湘西“蒿菜粑粑”原料植物鼠麴草总黄酮的微波响应面法提取工艺及鼠麴草的抑菌活性,在微波法提取单因素的基础上,采用响应面法考察了液料比、乙醇浓度、提取时间对得率的影响,并以K-B纸片法进行抑菌实验.结果显示,鼠麴草总黄酮最佳提取工艺为:液料比7∶1,乙醇浓度40%,微波提取时间9 min.最佳工艺下总黄酮的得率为3.62%.鼠麴草乙醇提取液对6种实验所用菌种(枯草芽孢杆菌Bacillus subtilis ATCC 6051、大肠埃希菌Escherichia coli ATCC 128、变形杆菌Proteus vulgaris ATCC 8427、藤黄八叠球菌Sarcina lutea CGMCC 1.880、白色念珠菌Canidia Albicans NCPC 1027和黑曲霉Aspergillus niger NCPC 1003)均表现出抑菌活性,分极性部位提取液中正丁醇部位、二氯甲烷部位与乙酸乙酯部位表现出各异的抗菌活性,以正丁醇部位为主要的抑菌活性部位且总黄酮含量最高.

In order to study the microwave response surface methodology for extracting total flavonoids from Gnaphalium affine,a raw material plant of Haocaibaba from Xiangxi region,and the bacteriostasis activity of Gnaphalium affine,based on the single factor extraction by microwave method,the effect of liquid to material ratio,ethanol concentration and extraction time on the yield was investigated by response surface method,and the antibacterial experiment was carried out by K-B paper method.The results showed that the best extraction process for total flavonoids from Gnaphalium affine was:liquid to material ratio of 7∶1,ethanol concentration of 40%,and microwave extraction time of 9 min.Under the optimal process,the yield of total flavonoids was 3.62%.Ethanol extract from Gnaphalium affine exhibited antibacterial activity against the strains used in the experiment(indicator bacteria:Bacillus subtilis ATCC 6051,Escherichia coli ATCC 128,Proteus vulgaris ATCC 8427,Sarcina lutea CGMCC 1.880,Canidia Albicans NCPC 1027 and Aspergillus niger NCPC 1003).The n-butanol,dichloromethane and ethyl acetate parts of the polar fraction extract showed different antibacterial activities,with n-butanol part as the main antibac terial active part and the highest total flavonoid content.