新疆风干肉中优势乳酸菌的分离及产酶特性分析

摘要

The dominant lactic acid bacteria (LAB) and the enzyme activities in the Xinjiang Air-dried meat were studied.Using the culturing method,LABs were screened and isolated.The isolates were then identified by 16S rRNA sequencing.The enzyme activities at different temperature.The results showed that the three isolation strains:Lactobacillus plantarum tL-4,Lactobacillus coryniformis tL-7,and Lactobacillus pentosus aL-16.The strain tL-4 and aL-16 showed higher lactic dehydrogenase activity (112.86 U/mL and 94.62 U/mL respectively) than tL-7.The strain aL-16 presented higher nitrite reductase activity,which reached 14.72 U/mL.Lactobacillus coryniformis had the lowest nitrite reductase activity (4.63U/mL).Compared with aL-16,the two strains tL-7 and tL-4 shoewd higher esterase activity,which were 13.25 U/mL and 11.45 U/mL,respectively.The inter-strain differences were presented in the optimal enzyme-producing temperature below.The optimum condition for the same strain also varied.The optimum temperature range for the isolated LAB strains to produce various enzymes were 30-40 ℃.Beyond this temperature range,the enzyme producing ability became weaker.%利用可培养方法,对新疆风干肉中乳酸菌进行分离筛选,结合生理生化和16S rRNA序列对其鉴定,并分析其在不同温度下的产酶特性.结果显示,菌株tL-4为植物乳杆菌(Lactobacillus plantarum);tL-7为棒状乳杆菌(Lactobacillus coryniformis),而菌株aL-16为戊糖乳杆菌(Lactobacillus pentosus).3株菌的乳酸脱氢酶活性都较高,相比而言,tL-4和aL-16比tL-7有较高活性,分别为112.86 U/mL和94.62 U/mL.aL-16的亚硝酸盐还原酶活力最高,为14.72 U/mL,tL-7的亚硝酸盐还原酶活力较低,为4.63 U/mL.菌株tL-7的酯酶活力较高为13.25 U/mL,tL-4的酯酶活力为11.45 U/mL,而aL-16的酯酶活力相对较低为9.67 U/mL.3株乳酸菌在不同温度下的产酶特性也不同,且菌株间的最适产酶温度存在差异,3株菌在30～ 40℃产酶能力强,超出这个温度范围,产酶能力下降.