Abstract

This eight-week feeding trial was conducted to investigate whether adding yeast cell wall extract mixed with bacteria producing mycotoxin-degrading enzymes (YEMDE) to an aflatoxin B 1 (AFB 1 )-contaminated diet affects the growth performance, liver health, antioxidant status, and intestinal microbiota status of juvenile turbot. A total of 480 fish were divided into four groups (three replicate tanks each group): basal diet (Control); Control diet supplemented with 100 μg/kg AFB 1 (AFB 1 ); and AFB 1 supplemented with 500 mg/kg or 1000 mg/kg YEMDE (AFY500 and AFY1000, respectively). The results showed that a minor variation in growth performance was observed among all groups ( P  > 0.05). Compared to the Control diet, the AFB 1 diet significantly deceased the activities of triglyceride and catalase in the serum ( P  < 0.05); Compared to the Control diet, the AFB 1 diet significantly increased the gene expression of cyp3a and apoptosis-related genes ( p53 , Bax, caspase3, caspase7 and caspase9 ) ( P  < 0.05), reduced the expression of catalase in the liver ( P  < 0.05); In addition, the AFB 1 diet negatively changed the communities of intestinal microbiota and down-regulated the abundance of some potential probiotics Bifidobacterium and Stenotrophomonas ( P  < 0.05). However, both the AFY500 and AFY1000 diets markedly recovered the antioxidant capacity, inhibited the apoptosis of hepatocytes, and improved the communities of intestinal microbiota ( P  < 0.05). More positive effects were observed in the AFY1000 group. Compared to the AFB 1 diet, the AFY1000 diet markedly increased the abundance of some potential beneficial bacteria in the intestine, such as Faecalibacterium and Lachnoanaerobaculum ( P  < 0.05). In conclusion, dietary YEMDE can effectively reduce the harmful impacts caused by AFB 1 on turbot, and in particular, it had beneficial effects on the communities of intestinal microbiota. It is promising to use YEMDE to control AFB 1 contami