摘要
大肠杆菌为低感染剂量肠道致病病原体,可引起严重的食品公共卫生问题。该研究从细胞壁通透性、胞内K+和生物大分子泄露、细胞表面疏水性、细胞膜通透性和表面zeta电位等方面系统研究了金属抗菌肽SIF_(4)对大肠杆菌的抑菌机制。研究发现,SIF_(4)的最小抑菌质量浓度为0.4 mg/L;SIF_(4)处理后菌体稳定期与衰亡期提前;细胞壁通透性与SIF_(4)浓度及温育时间呈正相关,温育1 h后,组别间细胞壁通透性有显著差异(P<0.05);胞内K+泄露随SIF_(4)浓度升高和温育时间延长呈递增趋势;胞内生物大分子泄露随SIF_(4)浓度升高与温育时间延长呈增加趋势,温育2 h后,试验组与对照组有显著差异(P<0.05);表面疏水性随SIF_(4)浓度增加呈递增趋势,SIF_(4)对细胞膜损伤可能以"毯式模型"进行;细胞表面zeta电位与SIF_(4)浓度呈线性递减趋势。研究认为,SIF_(4)可破坏细胞壁(膜)结构并使胞内容物泄露,可增强表面疏水性和降低表面zeta电位,造成细胞聚沉和生物代谢紊乱,最终诱导菌体凋亡,其可作为新型食品抗菌剂用于大肠杆菌的生物抑制。
The antimicrobial mechanism of SIF_(4) against Escherichia coli from cell wall permeability(CWP),intracellular K^(+)and biomacromolecule leakage,cell surface hydrophobicity(CSH),cell membrane permeability(CMP)and cell surface zeta potential(CSZP)were investigated.Results showed that minimum inhibition concentration of SIF_(4) was 0.4 mg/L.The stationary phase and decline phase of E.coli came early after treated by SIF_(4).CWP had a positively correlation with the SIF_(4) concentration and incubation time,after 1.0 h incubation,there was a significant difference between groups(P<0.05).The leakage of intracellular K+was enhanced with the increase of SIF_(4) concentration and incubation time;the leakage of intracellular biomacromolecules also increased with the increase of SIF_(4) concentration and incubation time,and there was a significant difference between the experimental group and the control group after 2 h incubation(P<0.05).CSH increased gradually with the increase of SIF_(4) concentration,and the cell membrane damaging caused by SIF_(4) might be carried out in“carpet model”.The CSZP had a linear decreasing tendency against SIF_(4) concentration.The research confirmed that SIF_(4) could destroy cell wall/membrane structure,cause leakage of intracellular substances,enhance CSH,reduce zeta potential,cause cell aggregation and metabolic disorder,and eventually induce cell apoptosis.All results deem that SIF_(4) could be adopted potentially as a new food antibacterial agent for the biological inhibition of E.coli.
作者
肖怀秋
李玉珍
林亲录
赵谋明
周全
赵一纯
XIAO Huaiqiu;LI Yuzhen;LIN Qinlu;ZHAO Mouming;ZHOU Quan;ZHAO Yichun(School of Pharmaceutical and Bioengineering,Hunan Chemical Vocational Technology College,Zhuzhou 412000,China;College of Food Science and Engineering,Central South University of Forestry and Technology,Changsha 410004,China;College of Food Science and Engineering,South China University of Technology,Guangzhou 510000,China)
出处
《食品与发酵工业》
CAS
CSCD
北大核心
2022年第1期111-116,共6页
Food and Fermentation Industries
基金
湖南省自然科学基金科教联合基金项目(2021JJ60040)
湖南省教育厅科研项目(20C0686)。
关键词
金属抗菌肽
大肠杆菌
细胞壁通透性
细胞膜损伤
metal antimicrobial peptide
Escherichia coli
cell wall permeability
cell membrane damage
