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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Vitamin synthesised from amino acid is
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The correct answer is  Vitamin synthesized from amino acid niacin.Niacin, or nicotinic acid, is a substituted pyridine derivative. The biologically active coenzyme forms are nicotinamide adenine dinucleotide (NAD+) and its phosphorylated derivative, nicotinamide adenine dinucleotide phosphate.Reference: Lippincott Textbook of Biochemistry, fifth edition, pg no. 379