西青果总鞣质中没食子酸和没食子酸乙酯含量测定及抗菌作用研究

Determination and antibacterial effects of gallic acid and gallic acid ethyl ester in Terminalia chebula Retz

目的建立西青果总鞣质中没食子酸和没食子酸乙酯含量的测定方法,并测定其对金黄色葡萄球菌(SA)的杀菌作用。方法采用甲醇和0.2%磷酸水为流动相,检测波长276 nm,流速1.0 mL/min,柱温30℃。测定总鞣质及没食子酸乙酯对SA的最小抑菌浓度(MIC)与最小杀菌浓度(MBC);透射电镜探究其抗菌作用机制。结果没食子酸和没食子酸乙酯线性范围分别为8~64 mg/L和14~110 mg/L,加样回收率分别为101.18%和100.04%,RSD分别为2.88%和3.59%。总鞣质和没食子酸乙酯对SA的MIC均为0.3125 g/L,MBC分别为1.250 g/L和0.625 g/L。结论该方法操作简便、快速、准确、灵敏度高、重复性好,能准确检测西青果总鞣质中没食子酸和没食子酸乙酯的含量。西青果总鞣质与没食子酸的杀菌机制与改变细菌细胞膜形态有关。

Objective To establish a method for determination of gallic acid and gallic acid ethyl ester in Terminalia chebula Retz, and to analyse the anti Staphylococcus aureus （SA） effect of total tannins and gallic acid ethyl ester. Methods Methanol and 0.2% phosphoric acid was used as mobile phase. The detection wavelength was 276 nm, the flow rate was 1.0 mL/min, and the column temperature was 30 ℃. MIC and MBC was determined to show the antibac- terial activity of total tannins and gallic acid ethyl ester against SA. Results The linear range of gallic acid and gal- lic acid ethyl ester were 8 - 64 mg/L and 14 - 110 mg/L. The recoveries of gallic acid and gallic acid ethyl ester were 101.18% and 100.04% respectively,and RSD were 2.88% and 3.59% respectively. The MIC of total tannins and gallic acid ethyl ester on SA were 0.3125 g/L,MBC were 1. 250 g/L and 0. 625 g/L respectively. Conclusion The method of determination is simple, rapid, accurate, high sensitivity and good repeatability, which can accurately detect the content of gallic acid and gallic acid ethyl ester in Terminalia chebula Retz. The sterilization mechanism of total tannins and gallic acid ethyl ester is associated with changing the morphology of bacterial cell membrane.