薄荷叶提取液对三种细菌抑菌效果的影响

将新鲜的薄荷叶用蒸馏水洗净晾干、无菌捣碎、过滤等获得薄荷叶提取液。配置不同浓度的提取液进行抑菌试验，用贴片法测量抑菌圈的直径，比较不同浓度的薄荷叶提取液对大肠杆菌、枯草芽孢杆菌和巨大芽孢杆菌的抑菌作用。试验表明，不同浓度的薄荷叶提取液所产生的抑菌圈大小不同，薄荷叶提取液对大肠杆菌、枯草芽孢杆菌和巨大芽孢杆菌均有一定的抑制作用，在浓度为80％时的抑菌作用最强，浓度大于80％和低于80％抑菌作用都有所降低。

Inhibition Effects of the Extracts from Peppermint Leaf on Three Kinds of Bacteria

The fresh peppermint leaves were washed with distilled water, and were dried, sterilely mashed, and filtered to obtain the exacts of peppermint leaf. Then the diameter of inhibition zone was measured with coating method in order to compare the inhibition effects of different concentrations of peppermint leaf extracts on bacteriostasis on Escherichia col, Bacillus subtilis and Bacillus megaterium. The results showed that the different concentrations of the peppermint extracts produced different sizes of inhibition zone, and the extracts of peppermint leaf had inhibition effect on Escherichia coil Bacillus subtilis and Bacillus megaterium; the inhibition effect reached the maximum when concentration of peppermint extracts was 80%, and the inhibition effect was weakened when concentration of peppermint extracts was either higher than 80% or lower than 80%.