苦瓜总皂甙最小抑菌浓度和最佳抑菌条件的研究

苦瓜总皂甙是苦瓜中有效成分,具有抑菌等作用。通过绘制生长曲线判断苦瓜总皂甙对大肠杆菌、金黄色葡萄球菌、枯草芽孢杆菌和黑曲霉菌生长曲线的影响。采用琼脂稀释法测定苦瓜总皂甙的最小抑菌浓度(MIC)。运用正交实验设计法确定苦瓜总皂甙的最佳抑菌条件。结果表明,苦瓜总皂甙对黑曲霉菌的生长几乎没有抑菌作用。浓度为50、100、150、200mg/mL的苦瓜总皂甙对大肠杆菌、枯草芽孢杆菌、金黄色葡萄球菌生长均有抑制作用,且以150mg/mL浓度时为最强,MIC分别为30、40、30mg/mL。苦瓜总皂甙对大肠杆菌和金黄色葡萄球菌的最佳抑菌条件为:40℃下,pH为6.0时,抑菌20h。 

Study on the minimum inhibitory concentrations and the optimal antibacterial conditions of momordicosides

Momordicosides were the active ingredient of Momordica Charantial L.and had antibacterial effects.The different antibacterial concentrations of momordicosides on Escherichia coli,bacillus subtilis,and staphylococcus aureus were judged by the growth curves.The minimum inhibitory concentrations(MIC) of momordicosides were detected by agar dilution methods.The best momordicosides antibacterial conditions of Escherichia coli,and staphylococcus aureus were detected by orthogonal experimental design methods.The results showed that momordicosides almost had no inhibition on the growth of Aspergillus niger.50,100,150,200mg/mL concentration of momordicosides could inhibit the growth of Escherichia coli,bacillus subtilis and Staphylococcus aureus.And the strongest inhibition concentration was 150mg/mL.The MICs of momordicosides on Escherichia coli,and staphylococcus aureus were both 30mg/mL,and on bacillus subtilis 40mg/mL.The best momordicosides inhibitory conditions of Escherichia coli and staphylococcus aureus were temperature at 40℃,inhibition time of 20h,and pH for 6.0.