荷叶提取液的抑菌特性研究

Studies on the Antimicrobial Characteristics of Lotus Leaf Extracts

为研究荷叶提取液对大肠杆菌的抑制特性,进行了不同提取液浓度、培养基pH值、热处理、环境离子浓度、作用时间对荷叶提取液抑菌作用影响的试验。结果表明:荷叶提取液对大肠杆菌的最低抑菌浓度(MIC)为0.125g/mL;抑菌pH值范围6～9;对高温处理较稳定;钠离子和镁离子的浓度对抑菌效果的影响不大;提取液与菌悬液作用3h可抑制大肠干菌的生长,从而说明荷叶提取液对大肠杆菌有较好的抑菌效果,且受环境条件的影响较小,为荷叶天然食品防腐剂的开发提供了理论基础。

In order to study the antimicrobial characteristics of lotus leaf extract, the effects of different factors on antimicrobial action were systematically studied in this paper, including the different extract concentrations, initial pH values of the medium, the stable of heat, the ion concentration of environmental, and the reactive times. Result showed that lotus leaf extract had strong antimicrobial effects on Escherichia coli. The minimum inhibition concentrations （MIC） was 0.125 g/mL. The pH range of antimicrobial was 6-9. The activities were effected by the longtime treatment under low temperature but not by the instant treatment at high temperature. Ion concentration had little influence on the antimicro- bial effect. The lotus leaf extract could completely restrain the growth of Escherichia coil in three hours. The lotus leaf extract had notable antimicrobial effects on Escherichia coli. The research will provide theoretical basis for development of nature lotus leaf preservative on food.