Abstract:Objective To isolate and screen novel Weizmannia coagulans strains with high stress tolerance.Methods Using commercially fermented pickle brine as the sample, W. coagulans strains were isolated, purified, and identified by selective culture medium methods, morphological observation, physiological and biochemical characterization, and 16S rDNA sequencing. Taking survival rate as the evaluation index, the stress tolerance of the isolated strains and three laboratory-preserved W. coagulans strains was determined under high-temperature (80~100 ℃), acidic (pH 2.0~3.0), and bile salt (0.1%~0.5%) conditions. Principal component analysis (PCA) was applied to comprehensively assess the stress tolerance of the tested strains.Results Two W. coagulans strains, WC412 and WC413, were screened. The results of stress tolerance determination and comprehensive evaluation showed that strain WC412 exhibited the best overall stress tolerance, followed by WC413, S17, S15, and S8.Conclusion Two novel W. coagulans strains, WC412 and WC413, were obtained from commercially fermented pickle brine. Among them, strain WC412 exhibited excellent comprehensive stress tolerance and has high potential for development and application.