Evaluation of probiotic potential and fermentation characteristics of Bacillus amyloliquefaciens LSG2‐8 from intestine of Rhynchocypris lagowskii

Abstract

In this study, 30 candidate bacterial strains were isolated from the intestine of Rhynchocypris lagowskii. LSG2‐8 was screened out through enzyme production test, antibiotic susceptibility test and anti‐pathogens ability. The LSG2‐8 was identified as Bacillus amyloliquefaciens. Bio‐safety assay confirmed that the LSG2‐8 was not pathogenic to the host fish and performed better in the tolerance test. The results of the adherence ability showed that the adhesion rate of LSG2‐8 was 36% in vitro intestinal mucosal adhesion model. Analysis of their surface‐adhesive proteins revealed that LSG2‐8 bacterial cell surface lectin mainly exhibited glycoprotein properties. The results of the interaction test on temperature, initial pH and inoculation amount showed that the optimum fermentation conditions for the LSG2‐8 were 30°C, 6.0 and 4%, respectively. In summary, the B. amyloliquefaciens LSG2‐8 from the intestine of R. lagowskii is a promising candidate strain for feed fermentation.