鼠李糖乳杆菌的培养上清液对几个致病菌和腐败菌的抑菌作用研究

研究了Lactobacillus rhamnosus6013菌在MRS中的最佳培养条件，再用琼脂杯扩散法研究该条件下的培养上清液对金黄色葡萄球菌、枯草杆菌、沙门氏菌、大肠杆菌和EHEC0157的抑菌作用，发现该菌的最佳培养条件为37℃，厌氧培养48h，该培养上清液对金黄色葡萄球菌、枯草杆菌、沙门氏菌有良好的抑菌作用。通过HPLC分析得知，乳酸含量高达4．38g/100mL，该浓度的乳酸溶液对金黄色葡萄球菌有很好的抑菌效果。抑菌效果受1mol／L的NaOH溶液，胰蛋白酶，胃蛋白酶处理的影响，表明发酵上清液的抑菌效果可能是乳酸和蛋白质类物质的综合作用。

STUDIES ON ANTIMICROBIAL EFFECTS OF LACTOBACILLUS RHAMNOS US 6013 CULTURE SUPERNATANTS ON SOME PATHOGENIC AND SPOILAGE MICROORGANISMS

The optimal fermentation conditions of Lac tobacillus rhamnosus 6013 in MRS medium, the inhibitory effect of this strain against Staphylococcus aureus, Bacillus cereus, Salmonella typhimurium, Escherichia coli and EHEC O157 by the agar-cup diffusion method and the characteristic of the culture supernatants were investigated. The Lactobacillus rhamnosus 6013 was grown best at 37 ℃ for 48 h anaerobicly. The culture supernatants produced at these culture conditions had good inhibition against growth of Staphylococcus aureus, Bacillus cereus and Salmonella typhimurium but less against rest of two. The observed content of lactic acid in culture supernatants was 4.38 % (M/V), which had excellent inhibitory effect on Staphylococcus aureus. The culture supernantants were partially affected by trypsin, pepsin and 1 mol/L NaOH solution treatments, suggesting that the overall inhibitory activity may be a combined action of lactic acid and proteinaceous substances.