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

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 degrees 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.

Automated summary

The bacterial strain LSG2-8 isolated from the intestine of Rhynchocypris lagowskii showed potential for feed fermentation, with good characteristics in terms of safety, adhesion, and fermentation conditions.