摘要
ε-聚赖氨酸是一种高安全性天然食品防腐剂,具有抑菌谱广、抑菌活性强的特点。该研究以大肠杆菌(Escherichia coli)和枯草芽孢杆菌(Bacillus subtilis)为指标菌,利用荧光探针5-氰基-2,3-二甲苯基氯化四唑检测菌体细胞在ε-聚赖氨酸处理前后的代谢活性,计算相对活性,考察ε-聚赖氨酸的杀菌效果,利用Linear和Weibull模型拟合杀菌动力学过程。结果表明:液体体系条件下低质量分数(0.005%)ε-聚赖氨酸与大肠杆菌作用15 min,活性下降至起始活性的86.33%,120 min时为73.44%;ε-聚赖氨酸作用质量分数为0.025%时,处理15 min时活性为起始活性的21.06%,120 min时仅为3.61%。ε-聚赖氨酸杀灭枯草芽孢杆菌的效果与大肠杆菌相近。动力学分析显示ε-聚赖氨酸杀菌效果的Linear模型拟合度低,R2值低于0.70,Weibull模型在测试质量分数范围可精确拟合杀菌动力学过程,R2值大于0.97。该研究表明基于细胞代谢活性指标,Weibull模型可准确拟合ε-聚赖氨酸杀菌动力学过程。
ε-Poly-L-lysine(ε-PL)is a natural and safe food preservative with a broad-spectrum and strong antimicrobial activity.In the present study,Escherichia coli and Bacillus subtilis were used to investigate their metabolic activity before and after treatment with the fluorescent probe,5-cyano-2,3-ditolyl tetrazolium chloride.The relative activity was calculated to investigate the bactericidal effect ofε-PL.Both the Linear and Weibull models were used to describe the bactericidal dynamics ofε-PL.For E.coli in liquid culture,a low-concentration ofε-PL(0.005%)applied for 15 and 120 min decreased metabolic activity of E.coli to 86.33%and 73.44%of its original activity,respectively.When a relative higher concentration of 0.025%was used,E.coli metabolic activity was only 21.06%after 15 min treatment and 3.61%at 120 min treatment.The bactericidal effect ofε-PL on B.subtilis was similar to that on E.coli.The kinetic analysis revealed that the fit of the Linear model was low,with an R2 value<0.70.By contrast,the Weibull model showed a better fit in all test concentrations ofε-PL against E.coli and B.subtilis,with an R2 value>0.97.The findings indicate that using metabolic activity as an index,the Weibull model can accurately fit the bactericidal kinetics ofε-PL.
作者
刘振杰
黄培豪
陈述
容顺
彭飞艇
陈玲
郭伟鹏
LIU Zhenjie;HUANG Peihao;CHEN Shu;RONG Shun;PENG Feiting;CHEN Ling;GUO Weipeng(Institute of Microbiology,Guangdong Academy of Sciences,Guangdong Detection Center of Microbiology,State Key Laboratory of Applied Microbiology Southern China,Guangdong Provincial Key Laboratory of Microbial Safety and Health,National Health Commission Science and Technology Innovation Platform for Nutrition and Safety of Microbial Food,Guangzhou 510070,China)
出处
《现代食品科技》
CAS
北大核心
2023年第11期94-100,共7页
Modern Food Science and Technology
基金
广东省科技厅广东省微生物安全与健康重点实验室项目(2020B121201009)。
