【摘要】 以大肠杆菌、枯草芽孢杆菌、青霉为研究对象,考察ε-聚赖氨酸的抑菌作用。首先通过抑菌实验确定ε-聚赖氨酸对大肠杆菌,枯草芽胞杆菌的最小抑菌浓度均为25mg/L,对青霉最小抑菌浓度为200mg/L。对于不同细菌,ε-聚赖氨酸表现出相似的抑菌动力学特征。通过细胞损伤实验,研究ε-聚赖氨酸不同浓度、不同时间后对菌体造成的伤害。通过细胞形态观察以及生化检测研究ε-聚赖氨酸对细菌的抑菌机理。初步结论:当ε-聚赖氨酸作用于菌体细胞后,逐渐破坏细胞结构,最终导致细胞死亡,从而起到抑菌作用。更多还原

【Abstract】 Antimicrobial effect of ε-poly-L-lysine against Gram-negative Escherichia coli, Gram-positive Bacillus subtilis and Penicillum were studied by colormetry. Analysis on bacteria cell injury was conducted to investigate the detrimental effects of varying concentration of ε-poly-L-lysine and incubation time with ε-poly-L-lysine at its minimum inhibitory concentration on the morphology of bacteria. Results indicated that the MIC against the above two bacteria is less than 25 mg/L and less than 200 mg/L against Penicillium. ε-Poly-L-lysine shows analogical antimicrobial kinetics against different bacteria. The mechanism of action was further investigated by cell integrity and outerand inner-membrane permeability assays and the profile of protein expression in bacteria. ε-Poly-L-lysine killed pathogenic bacteria by causing irreversible changes in both the inner and outer membranes.更多还原