耐酸乳酸菌的筛选及生长特性研究

Study on screening and growth characteristics of lactic acid bacteria with acid resistant ability

从徐州地区天然发酵泡菜中筛选出一株耐酸能力较强的菌株HLAB0143,该菌株能在pH2.5的条件下生长;通过形态、生理生化和16sDNA序列测定,确认该菌株为干酪乳杆菌;在单因素实验的基础上进行正交实验,确定了该菌株的最佳生长条件,即温度为37℃,初始pH为5,接种量为1%(v/v)。对其耐酸机制进行了初步研究,认为谷氨酸脱羧酶活性是其耐受低酸性环境的机制之一。

The strain HLAB0143 with acid resistant ab The strain could grow under pH2.5. The strain was ty was screened from Xuzhou natural fermented pickles. identified Lb. casei by morphological,physiological and biochemical characteristics and 16sDNA sequence analysis. Orthogonal experiments were carried out based on single factor experiments ,the optimal growth parameters for this strain was determined ,the temperature was 37℃,the original pH was 5,inoculation amount was 1% （v/v）. The acid mechanism was studied,glutamic acid decarboxylase activity was one of the mechanism of resistance low acid environment.