Chapter 16 - Pantothenic Acid

Abstract

Pantothenic acid functions as the essential precursor of coenzyme A (CoA) and acyl carrier protein (ACP). It is widely distributed in foods, particularly meats, although cooking, canning, and freezing can cause significant degradation. As pantothenic acid occurs in food primarily as CoA and ACP, hydrolytic digestion of these protein complexes must occur to release the free vitamin for absorption. As a water-soluble vitamin, pantothenic acid is absorbed by active transport and facilitated diffusion. CoA and ACP function metabolically as carriers of acyl groups and activators of carbonyl groups in a large number of vital metabolic transformations, including the tricarboxylic acid cycle and the metabolism of fatty acids. Acyl CoAs serve as essential cofactors for at least 100 enzymes involved in intermediary metabolism, ACP is a component of the multienzyme complex fatty acid synthetase. Deficiency in humans is rare and only occurs in severely malnourished individuals or with the use of an antagonist. Neurologic symptoms have been reported in pantothenic acid nutritional deficiency.