四川发酵香肠中乳酸菌的分离与鉴定

Isolation and identification of lactic acid bacteria in Sichuan fermented sausage

从四川发酵香肠中分离得到126株乳酸菌,采用透明圈法进行初筛,以发酵特性为复选指标,筛选得到2株乳酸杆菌(L1、L2)和1株乳酸球菌(P3)。对筛选出的3株乳酸菌研究其主要发酵特性,并进行产酸、耐盐和耐亚硝酸实验。结果表明,乳酸杆菌与乳酸球菌的产酸特性不同,杆菌比球菌生长快,pH下降快;3株乳酸菌对食盐和亚硝酸盐均具有较好的耐受性;对蛋白质、脂肪无明显的分解作用;对大肠杆菌、金黄色葡萄球菌有较好的抑制作用。生化鉴定以及菌株的16SrRNA测序结果表明,L1为植物乳杆菌,L2为植物乳杆菌,P3为戊糖片球菌。

A total of 126 strains of lactic acid bacteria（LAB） were isolated from Sichuan natural fermented sausages,two strains of lactobacillus（L1,L2） and one strain of streptococcus lactis（P3） were selected by transparent ring method and fermention capacity. Their important fermentation characteristics were identified by acid-producing,salt-tolerating and nitrite-tolerating experiments,respectively. Results indicated that there were some differences in growing curve and the ability of producing acid between the lactobacillus and the streptococcus lactis. The growth rate and pH decline rate of lactobacillus were more quickly than streptococcus lactis. Three strains of lactic acid bacteria exhibited excellent tolerance to salt and nitrite, no degradation ability to protein and fat,and excellent inhibitory effect against Escherichia coil and Staphylococcus aureus. According to biochemical characteristics and 16S rRNA sequences, L1, L2, P3 were identified to be Lactobacillus plantarum, Lactobacillus plantarum, Pediococcus pentosaceus.