Bacillus velezensis FiA2 as an Oxydifficidin-Producing Strain and its Effects on the Growth Performance, Immunity, Intestinal Microbiota, and Resistance to Aeromonas salmonicida Infection in Carassius carassius.

ABSTRACT: In aquaculture, biological control of bacterial infections is a promising strategy that, aside from preventing infections, also benefits the host in several ways. In this study, a Bacillus strain FiA2 isolated from the gut of Carassius carassius (crucian carp) exhibited broad spectrums of activity against multiple aquatic bacterial pathogens. The compound with antibacterial activity was successfully separated and identified as oxydifficidin, with a m/z of 559.47. The oxydifficidin retained its activity even after being exposed to high temperatures, ultraviolet light, proteolytic enzymes, chemical reagents, and alkaline and acidic pH. Furthermore, crucian carp, when supplemented with FiA2 in diet, reduced the infection rate (post-challenged survival rate of 45%), increased the total weight

SUBMITTER: Khan TA 

PROVIDER: S-EPMC12532693 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature