烟酸也称为维生素PP或维生素B_3,是尼克酸和烟酰胺(尼克酸酰胺)及具有烟酰胺生物活性的衍生物的统称。烟酸的生理功能主要是作为辅酶的基本组成成分参与细胞的代谢过程。在体内,烟酰胺与ATP反应形成烟酰胺腺嘌呤二核苷酸(NAD)和烟酰胺腺嘌呤二核苷酸磷酸(NADP),它们作为脱氧化氢酶的辅酶,在许多生物性氧化还原反应中起电子受体或氢供体的作用。烟酸在血液中的主要形式是烟酰胺。膳食中烟酸 Niacin, also known as vitamin PP or vitamin B_3, is the generic name for nicotinic acid and nicotinamide (nicotinamide) and derivatives with the biological activity of nicotinamide. The physiological function of niacin is mainly involved in the metabolic process of cells as the basic component of coenzyme. In vivo, nicotinamide reacts with ATP to form nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP), which act as coenzymes of catalase and are found in many biological redox reactions In the role of the electron acceptor or hydrogen donor. The main form of nicotinic acid in the blood is nicotinamide. Dietary niacin