三种中草药提取物对大肠杆菌的抑制作用

Inhibitory Effect of Chinese Herbal Medicine Extracts on Escherichia Coli

文章以大肠杆菌为实验对象,用地榆、大黄、苦参三种中草药的乙醇提取液研究对该菌的抑制作用.通过培养法测定三种中草药的抑菌率、最小抑菌浓度,大黄、苦参最小抑菌浓度为1000 mg/mL;地榆最小抑菌浓度为500 mg/mL,抑菌率达100%,用此最小抑菌浓度经比浊法测出大肠杆菌的生长曲线,与对照组对比得出:地榆乙醇提取液作用下的大肠杆菌对数生长期缩短,衰亡期延长,且吸光度值(OD)均低于对照组,说明地榆对大肠杆菌的抑制作用较强,而大黄和苦参前期吸光度值(OD)低于对照组,但在22 h后,两者曲线呈上升状态,说明此阶段抑制作用在减弱.因此,大黄和苦参的乙醇提取液对大肠杆菌抑制作用较地榆弱.

The escherichia coli were used as the experimental object.The ethanol extracts bacteriostasis on Escherichia coli of three kinds of Chinese herbal medicine including the Sanguisorba officinalis,rhubarb and Sophoraflavescens were studied to study the inhibitory effect of the bacteria.The inhibition rate of two kinds of Chinese herbal medicine and the minimum bacteriostasis concentration by cultivating method,it was concluded that rhubarb,bitter and the minimum bacteriostasis concentration of 1000 mg/mL.The minimum inhibitory concentration of Elm was 500mg/mL,and the inhibitory rate reached 100%.The growth curve of E.coli was measured by turbidimetry with this minimum inhibitory concentration.Compared with the control group,the logarithmic growth period and death period of E.coli were shortened and the absorbance(OD)values were all lower than those of the control group.While rhubarb and sophora early absorbance value(OD)value is lower than the control group,but after 22 h,both curve rising trend,that is weakened inhibition in at this stage.Therefore,the bacteriostasis effect of the ethanol extracts of rhubarb and Sophoraflavescens on Escherichia coli was weaker than that of Sanguisorba officinalis.