ε-聚赖氨酸抑菌性能研究

Study on the Antimicrobial Activity of ε-Polylysine

分别采用分光光度法、菌体量法以及孔扩散法研究了ε-聚赖氨酸对细菌和真菌的抑菌活性及ε-聚赖氨酸浓度、pH值和温度对其抑菌活性的影响。结果表明,ε-聚赖氨酸对金黄色葡萄球菌、大肠杆菌、黄曲霉、枯草芽孢杆菌、酿酒酵母、保加利亚乳杆菌等6种供试微生物均有一定的抑制作用,对大肠杆菌、金黄色葡萄球菌、保加利亚乳杆菌抑制效果较好,对黄曲霉较差;对各种菌的最小抑菌浓度(MIC)为大肠杆菌、金黄色葡萄球菌、保加利亚乳杆菌12.5 mg/L;枯草芽孢杆菌25 mg/L;酿酒酵母800 mg/L;黄曲霉1 600 mg/L。ε-聚赖氨酸的抑菌活性随其浓度的增加而增强,热稳定性非常好,能耐100℃的高温,在pH5～8抑菌活性最强,与甘氨酸、Nisin都有协同增效的作用。

The anti-microbial activity of ε-Polylysine and its effect factors（ including concentration, pH value,temperature ） were studied by spectrophotometry, dry bacteria cell weight and aperture pervasion method. The results showed that ε-Polylysine had a inhibition function on Staphylococcus aureus, Escherichia coli , Aspergillus flavus , Bacillus subtilis , Saccharomyces cerevisiae and Lactobacillus bulgaricus , the antimicrobial action was especially notable to Escherichia coli, Staphylococcus aureus and Lactobacillus bulgaricus, and it was not very effective to Aspergillus flavus. The minimal inhibitory concentration （MIC） was 12.5mg/L for Escherichia coli , Staphylococcus aureus and Lactobacillus bulgaricus, 25 mg/L for Bacillus subtilis, 800mg/L for Saccharomyces cerevisiae, 1 600mg/L for Aspergillus flavus. And it was proved that the stronger the concentration of ε-PL is, the stronger the anti-microbial activity is. It was also proved that e-Polylysine has very good thermal stability, being able to endure as high as 100℃ temperature and it can be effective from pH5-8. Besides, the addition of glycine or Nisin can improve antimicrobial ac tivity of ε-Polylysine.