酸适应海德尔堡沙门氏菌对环境胁迫耐受性分析

发布时间：2018-09-04 12:28

【摘要】：目的:研究海德尔堡沙门氏菌(Salmonella heidelberg)低pH值酸适应性及酸适应对细胞其他胁迫环境耐受性的影响。方法:海德尔堡沙门氏菌在pH 5.5酸性培养基中生长2h诱导酸适应性,以pH 3.0酸胁迫培养基及不同温度、NaCl、胆盐、消毒剂环境的存活率评价其耐受性。结果:pH 5.5酸适应2 h后,海德尔堡沙门氏菌在pH 3.0酸胁迫环境的存活率大幅提高。低pH值酸适应也使海德尔堡沙门氏菌在45、50℃高温条件下的存活率显著提高,对4℃冷藏环境的耐受性显著低于非酸处理菌株,但对-20℃冷冻环境的生存无影响。酸适应海德尔堡沙门氏菌对高渗、胆盐胁迫也表现良好的耐受性,5~10 g/100mL NaCl溶液处理1 h,酸适应海德尔堡沙门氏菌的存活率大于60%,在1~10 g/100mL胆盐溶液的存活率比对照组高3.8倍。海德尔堡沙门氏菌酸适应性也使其对消毒剂的敏感性发生变化,酸适应性海德尔堡沙门氏菌在10~25 mmol/LH_2O_2溶液的存活率显著高于对照菌株,最高达3.1倍;但对NaClO、乙醇消毒剂的耐受性显著降低,高质量浓度下二者无显著差异。结论:海德尔堡沙门氏菌在低pH值酸性条件生长一段时间会诱导产生酸适应性,还会协同提高其对高温、高渗、胆盐、H_2O_2胁迫环境的交叉抗性;但对4、-20℃低温、NaClO、乙醇等杀菌、保藏措施敏感性提高。
[Abstract]:Aim: to study the low pH acid adaptability of (Salmonella heidelberg) and the effect of acid adaptation on the tolerance of other stress environments of Salmonella heidelliensis. Methods: the acid adaptability of Salmonella Heidelberg was induced in pH 5.5 acid medium for 2 h. The tolerance was evaluated by the survival rate of pH 3.0 acid stress medium and NaCll, bile salt and disinfectants at different temperatures. Results the survival rate of Salmonella Heidelberg under acid stress of pH 3. 0 was significantly increased after 5. 5% acid acclimation for 2 h. Low pH acid adaptation also increased the survival rate of Salmonella Heidelberg at 45 鈩，

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