食品科学2017，Vol.38Issue(8)：1-5,5.DOI:10.7506/spkx1002-6630-201708001
超高压对大肠杆菌O157∶H7细胞膜的损伤效应
Cell Membrane Injury of Escherichia coli O157∶H7 Caused by Hydrostatic Pressure
摘要
Abstract
This study investigated the membrane injury of Escherichia coli O157∶H7 cells exposed to high hydrostatic pressure.Different pressure levels (200,400 and 500 MPa) were used to evaluate the inactivation of the bacteria.The leakage of nucleic acids,K+ and Mg2+,and propidium iodide (PI) intake of the cells,as well as changes in Na+/K+-ATPase and Ca2+/Mg2+-ATPase activities were determined after pressure treatment.Results indicated that,after 200 and 400 MPa treatments for 5 min,the number of viable cells decreased from an initial level of 8.8 to 8.2 and 6.3 (lg(CFU/mL)),respectively.When treated at 500 MPa,no viable cells were detected on plate count agar.As the pressure level rose,the leakage of intratracellular constituents and the fluorescence (OD) of PIintake increased significantly and both enzyme activities significantly decreased.Ca2+/Mg2+-ATPase was more sensitive to pressure than Na+/K+-ATPase,and the enzyme activities were almost completely inactivated after pressurization at 500 MPa.High pressure treatment caused obvious damage to the membrane of E.coli O157∶H7 cells.The major cause ofE.coli O157∶H7 death after high hydrostatic pressure treatment was the inactivation of Ca2+/Mg2+-ATPase.关键词
超高压/大肠杆菌O157∶H7/细胞膜Key words
high hydrostatic pressure/Escherichia coli O157∶H7/cell membrane分类
生物科学引用本文复制引用
孔晓雪,付勇,姬赛赛,江芸,张志国..超高压对大肠杆菌O157∶H7细胞膜的损伤效应[J].食品科学,2017,38(8):1-5,5.基金项目
国家自然科学基金面上项目(31371861) （31371861）
