降亚硝酸盐乳酸菌的鉴定及生长特性的研究

Study on identification and growth character of lactic acid bacteria strains degrading nitrite

从传统发酵食品中分离乳酸菌,筛选鉴定降解亚硝酸盐能力较强的菌株,并研究其在白菜汁培养基中的生长及产酸情况,为制作泡菜发酵剂储备优良菌株。结果分离了144株乳酸菌,并获得5株亚硝酸盐降解率在99%以上的菌株,经鉴定菌株Mao21.1和Mao6.2为戊糖乳杆菌,Wang3.1和Mao20.1为植物乳杆菌,Lin2.4为戊糖片球菌。5株菌在白菜汁培养基中生长4h后,各菌株培养液的pH均快速下降;培养20h后,除菌株Mao21.1外,其他菌株培养液pH均降到3.5以下;对数生长末期菌株Mao6.2和Lin2.4活菌数达到108cfu/mL,该两株菌可作为制作泡菜发酵剂的储备菌株。

Lactic acid bacteria strains with high nitrite degradation ability were isolated,screened and identified from traditional fermented food as the good strains for pickler starter through researching the strains growth and acid production in cabbage juice culture medium.The result was that nitrite degradation rate of 5 strains selected from 144 lactic acid bacteria strains separated be more than 99%.The identification result indicated that Mao21.1 and Mao6.2 were Lactobacillus pentosus,Wang3.1 and Mao20.1 were Lactobacillus plantarum,Lin2.4 was Pediococcus pentosaceus.5 strains were cultured in Chinese cabbage juice after 4h,pH values of the culture medium were falling fast.After 20h,pH values were all below 3.5 except Mao21.1.The count of Mao6.2 and Lin2.4 cultured in cabbage juice reached 108cfu/mL in logarithmic growth stage,the two strains could be used as reserve strains of making pickler starter.