K. Banno
1997
Citations
0
Influential Citations
7
Citations
Journal
Methods in enzymology
Abstract
Publisher Summary This chapter investigates the properties of hopantenic acid (HOPA)—a natural homolog of pantothenic acid (PaA) containing γ -aminobutyric acid (GABA) in place of β -alanine. Its calcium salt and pharmacologic properties have been used to improve blood circulation and metabolism in the brain. Because hopantenic acid is used pharmacologically it is important to be able to determine HOPA and PaA separately for pharmacokinetic studies. Gas chromatography–mass fragmentography (GC–MF) has been used to assay HOPA after administration of calcium hopantenate. Other methods for the assay of HOPA have also been developed, such as the GC–MF determination of pantoyllactone, which is a product of HOPA hydrolysis, the colorimetric determination of GABA with sodium 1,2-naphthoquinone 4-sulfate, and a high-performance liquid chromatographic (HPLC) method with 9-anthryldiazomethane as a fluorescent derivative. A bioassay method using Lactobacillus arabinosus for the determination of trimethylsilylated pantoyllactone by GC–MF and for the assay of PaA is developed. The simultaneous rapid microanalysis for PaA and HOPA in biological samples and natural products by GC–MF with a wide-bore column and multiple ion detection (MID) is described in the chapter. 5-[(2,4-dihydroxy-3,3-dimethyl-1-oxobutyl)amino]pentanoic acid calcium salt is used as an internal standard (IS) to measure PaA and HOPA simultaneously in plasma samples from humans, monkeys, dogs, pigs, rabbits, mice, rats, chickens, and soft-shelled turtles; in brain samples of chicken and soft-shelled turtle; and also in natural products.