Ca^2+、Mg^2+对苦丁茶总黄酮提取及其抑菌活性的影响

Effects of Ca^2+and Mg^2+on the Extraction and Antibacterial Activity of Total Flavonoids from Ilex kudingcha

在苦丁茶总黄酮的提取环节引入合适量的Ca^2+、Mg^2+,采用单因素试验和响应面法优化总黄酮的提取工艺,并研究Ca^2+、Mg^2+的加入对总黄酮提取物抑菌活性的影响。结果表明,总黄酮提取的最佳工艺是:Ca^2+浓度181 mg·L^-1、Mg^2+浓度180 mg·L^-1、乙醇浓度57%、料液比1:29、提取时间为1 h,此时提取率达到10.14%,引入Ca^2+、Mg^2+能明显提高苦丁茶总黄酮的提取效率。抑菌测试结果表明:引入Ca^2+、Mg^2+离子的苦丁茶总黄酮提取物对大肠杆菌、金黄色葡萄球菌、枯草芽孢杆菌的最小抑菌浓度(MIC)分别为12.18、6.09、12.18 mg·mL^-1,低于不含Ca^2+、Mg^2+离子的总黄酮提取物的MIC值,可见,Ca^2+、Mg^2+的引入可以增强苦丁茶总黄酮提取物的抑菌活性。

An appropriate amount of Ca^2+and Mg^2+was added to the extraction of total flavones from Kudingcha.The single factor test and response surface methodology were used to optimize the extraction process,and the effects of the added Ca^2+and Mg^2+on the antibacterial activity of total flavone extract were investigated.The results showed that the optimal extraction process of total flavonoids in Kudingcha was the Ca^2+concentration of 181 mg·L^-1,the Mg^2+concentration of 180 mg·L^-1,the ethanol concentration of57%,the solid-liquid ratio of 1:29 and the extraction time of 1 h.In the condition,the extraction rate reached 10.14%,and revealed the introduction of Ca^2+ and Mg^2+ could significantly improve the extraction efficiency of total flavonoids.Bacteriostatic test results showed that the minimum inhibitory concentration(MIC)of total flavone extract against E.coli,S.aureus and B.subtilis were 12.18,6.09 and 12.18 mg·m L^-1,respectively,which was lower than that without Ca^2+and Mg^2+.It can be proved that the introduction of Ca^2+and Mg^2+can enhance the antibacterial activity of total flavonoids extracts in Kudingcha.