Analysis of gamma-aminobutyric acid in gabaron tea by ionchromatography [Japanese]

摘要

Gabaron tea is the special tea enriched with gamma-aminobutyric acid by anaerobic treatment of fresh tea leaves. For analyzing gamma-aminobutyric acid in gabaron tea an ionchromatographic method was newly developed, Optimum mobile Phase concentration attaining more separative analysis and Preparation methods obtaining complete extraction of gamma-aminobutyric acid were investigated. A low coefficient of variation in determined values and high recovery percentages of pure gamma-aminobutyric acid added to sample teas were obtained. Experimental values obtained here agreed well with those obtained by the conventional method in the gamma-aminobutyric acid content. The proposed method in this paper provides simple and accurate analysis of gamma-aminobutyric acid : there is no need to use precolunn derivatization by o-phthalaldehyde and removal of polyphenols in sample preparation, and employment of gradient elution and internal standard in measurement as required in the conventional method.