A review on physiological, behavioral and metabolic role of dietary tryptophan in fish

Abstract

Tryptophan is the sole amino acid in proteins deriving from the indole group that gives an advantage in life chemistry either from metabolizing its C11 skeleton or using its –R residue in proteins and peptides for structural stability. The input of tryptophan in a fish from external sources makes it one of the fundamentally essential amino acid supplies that can be managed and controlled in aquaculture practices for desirable performance of physiological and metabolic activities. As the precursor of serotonin, their roles as stress suppressor in several fish species have been well studied. Studies have shown that the enhancement of serotonin synthesis in the brain via supplementary dietary tryptophan has been linked to various behavioral patterns like aggression, stress reaction, feeding, fish maturation, social dominance and sexual behavior. The impact of tryptophan in various physiological, behavioral and metabolic aspects of fish has been generalized in the current review in the hope of futuristic insights and scope in the role that tryptophan plays in fish and aquaculture.