Pyridoxine and Its Biological Functions in Fish: Current Knowledge and Perspectives in Aquaculture
M. S. Akhtar, Alexander Ciji
Abstract
The prominent functional versatility of pyridoxine makes it an essential dietary nutrient for aquatic animals. Ample investigations have been undertaken to determine the optimum levels of dietary pyridoxine for different commercial fish species. Available literature suggests that the pyridoxine requirement of animals, including fish, varies greatly depending on the dietary protein intake. The present review recapitulates the existing knowledge on the extensive range of physiological functions of pyridoxine, which includes its central role in the metabolism of various biomolecules including proteins, lipids, and nucleic acids, regulation of immune responses, biosynthesis of different neurotransmitters and porphyrins/heme. The antioxidant property of pyridoxine offers tremendous health benefits in different animals. The prospective role of pyridoxine as a stress mitigator forced to recommend high dose pyridoxine as an ‘anti-stress strategy’ in different animals, including fish. The potential of pyridoxine to enhance thermal tolerance and cold adaptation in fish is also highlighted in this review. Future studies are still necessary to unravel the exact mechanism by which pyridoxine potentiates thermal tolerance in aquatic animals. Further, the investigations on the optimum requirement of pyridoxine in many aquaculture candidate species are still missing, and this needs to be explored in the future.