渗透压胁迫对耐盐乳酸菌发酵特性的影响

采用传统分离培养法从新疆伊犁昭苏县土壤样品中分离筛选耐盐乳酸菌，通过形态观察及分子生物学技术对其进行鉴定，并探究高盐胁迫（7%、8% NaCl）下其生长速率、产酸性能、耐酸、耐胆盐胁迫能力的变化。结果表明，筛选得到4株耐盐乳酸菌，其中菌株a、b、c被鉴定为海氏肠球菌（Enterococcus hirae），菌株d被鉴定为植物乳杆菌（Lactobacillus plantarum）。在高盐胁迫（7%、8% NaCl）下，L. plantarum d的生长特性、产酸及耐酸性能最好，但耐胆盐能力最差，E. hirae a、b、c的耐胆盐胁迫能力更佳；在10%和12%的NaCl含量下胁迫3 h，4株菌的存活率均能维持在36%以上，其中E. hirae b的耐盐能力最佳，存活率最高。

Effect of osmotic stress on the fermentation performance of salt tolerant lactic acid bacteria

Using traditional isolation methods, the salt tolerant lactic acid bacteria were isolated and screened from the soil samples in Zhaosu County, Yili, Xinjiang, and identified by morphological observation and molecular biology techniques. Changes in growth rate, acid production performance, acid tolerance and bile salt tolerance of the screened strains under high salt (7%, 8% NaCl) stress were investigated. The results showed that 4 strains of salt tolerant lactic acid bacteria were screened, of which strains a, b and c were identified as Enterococcus hirae and strain d was identified as Lactobacillus plantarum. The growth characteristics, acid production performance and acid tolerance of L. plantarum d was the optimal under high salt stress (7%, 8% NaCl), but the bile salt tolerance was the worst. The bile salt tolerance of E. hirae a, b, c was better. Under the stress of 10% and 12% NaCl for 3 h, the survival rate of the 4 strains could be maintained at more than 36%, of which E. hirae b had the optimal salt tolerance and the highest survival rate.