The metabolism and antioxidant properties of probiotics and prebiotics in fish: a review

The issue of antimicrobial resistance in farm-raised fish presents a significant challenge for aquaculture operations. Long-term antibiotic treatment of fish for bacterial infections has led to bacteria thriving in the aquatic ecosystem and developing resistance to antibiotics. On the other hand, increasing research suggests that probiotics and prebiotics may be viable alternatives to antibiotics in regulating the immune system. Probiotics and prebiotics interact with fish metabolism in complex ways. These interactions offer promising alternatives to reduce antibiotic use in aquaculture. Introducing live microorganisms, known as probiotics, into an organism’s system can help improve overall health by altering the microflora and boosting immunity. Acting as immunostimulants, prebiotics directly impact the fish’s innate immune system. When used together, probiotics and prebiotics enhance immunomodulatory activity, providing numerous health benefits to aquatic animals. However, successfully replacing antibiotics with probiotics and prebiotics requires a deep understanding of metabolic pathways, optimization strategies, and innovative approaches. There has been a lack of extensive research on how probiotics and prebiotics impact lipid metabolism in various types of fish. This review aims to explore the intricate relationship between probiotics, prebiotics, and fish metabolism, with a specific focus on how these beneficial microorganisms and dietary fibers interact with fish antioxidant systems. We have also discussed the challenges faced by farmers when using probiotics and prebiotics. This review analyzes metabolic and antioxidant interactions mediated by probiotics and prebiotics in cultured fish species. It synthesizes findings on histological effects, enzymatic activity, and microbial interactions, with emphasis on lipid metabolism and immune modulation, and also discusses the practical implications for sustainable aquaculture.