Pyridoxal is the aldehyde form of vitamin B6 and serves as a precursor to the active coenzyme pyridoxal 5'-phosphate (PLP). It participates in over 140 enzymatic reactions, primarily in amino acid metabolism including transamination, decarboxylation, and racemization. Naturally occurring in animal-derived foods such as meat, fish, and poultry, it is heat-labile and can be lost during cooking. Pyridoxal is interconvertible with pyridoxine and pyridoxamine in vivo and is essential for neurotransmitter synthesis, hemoglobin formation, and glycogenolysis. Its structure features a pyridine ring with hydroxyl, hydroxymethyl, methyl, and formyl substituents.