摘要
为了提高溶菌酶对革兰氏阴性菌的抑菌性能,研究蛋清溶菌酶和渗透剂甘氨酸、EDTA-Na2复配对大肠杆菌ATCC25922、DH5α的抑菌效果,及细胞外膜渗透性和细胞表面形态的变化。结果表明:大肠杆菌ATCC25922对溶菌酶的敏感性明显强于DH5α,其外膜渗透性也高于大肠杆菌DH5α。当溶菌酶分别和渗透剂甘氨酸或EDTA-Na2复配后,对大肠杆菌ATCC25922和DH5α的抑菌性能都显著提高;三者共同作用时,对大肠杆菌ATCC25922的抑菌能力从101.0提高到103.45,对大肠杆菌DH5α则从100.35提高到103.15,表现出协同抑菌作用。细胞外膜渗透性的N-苯基-1-萘胺(NPN)测定结果表明:溶菌酶与甘氨酸、EDTA-Na2复配后,两种大肠杆菌的外膜渗透性相应提高,TEM电镜结果也证实溶菌酶与渗透剂对大肠杆菌细胞表面有协同破坏作用。因此改善大肠杆菌的外膜渗透性有助于增强溶菌酶对其抑菌效果。
In order to enhance the antibacterial activity of hen egg white lysozyme against gram-negative bacteria such as Escherichia coli ATCC25922 and DH5α,the antibacterial effect of lysozyme combined with each or both of the permeabilizers glycine and ethylenediaminetetraacetate(EDTA-Na2) was analyzed,and the outer membrane permeability and cell surface morphology of E.coli were also examined.The results showed that ATCC25922 was more sensitive to lysozyme than DH5α and its outer membrane permeability was higher than that of DH5α.Due to the combinatorial application with glycine or EDTA-Na2,the antimicrobial activity of lysoyme against both E.coli strains was obviously improved,which indicated the synergistic antibacterial effect of lysoyme and each of the permeabilizers.1-N-phenylnaphthylamine(NPN) uptake assay showed that the outer membrane permeability of E.coli strains was increased when the cells were treated with lysozyme supplemented with cell permeabilizers.TEM image of ATCC 25922 cells also revealed the synergistic effect of lysozyme supplemented with cell permeabilizers on damaging cell surface structure.Therefore,improving the outer membrane permeability of E.coli is helpful for enhancing the antibacterial effect of lysozyme on the bacterium.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2011年第11期176-180,共5页
Food Science
基金
食品科学与技术国家重点实验室自由探索资助课题(SKLF-TS200802)