Patent ID: 10638771

Abstract:
The present invention relates to a mutant strain of Lactococcus lactis and its application, and belongs to the field of food biotechnology. The mutant strain, Lactococcus lactis WH101, was screened for its better tolerance to harsh environmental factors, especially higher acid tolerance. The OD600 of Lactococcus lactis WH101 was increased by 5.5 times than that of the parent strain when cultured at pH 4.5. The survival rate of the mutant strain was 22.4 times higher than that of the parent strain after 3 hr treatment in pH 4.0 culture medium. The survival rate of the mutant strain was 5.2, 2.0 and 1.9 times over that of the parent strain treated with 15% ethanol for 4 hr, 15% NaCl for 6 hr and 1 mM H2O2 for 3 hr, respectively.