Usefulness of Catechins and Caffeine Profiles to Determine Growing Areas of Green Tea Leaves of a Single Variety, Yabukita, in Japan

Abstract

Yabukita green tea leaves in Shizuoka, Kagoshima and Mie areas in Japan were analyzed for catechins and caffeine using 6-O-α-D-glucosyl-β-cyclodextrin-modified micellar electrokinetic chromatography (6G-β-CD-modified MEKC). Caffeine and seven catechins [(-)-catechin (C), (+)-C, (-)-epicatechin (EC), (-)-catechin gallate (CG), (-)-epicatechin gallate (ECG), (-)-epigallocatechin (EGC) and (-)-epigallocatechin gallate (EGCG)], but not (+)-EC, were detected in all extracts. Linear discriminant analysis was applied to differentiate green tea samples according to their geographical origins. As a result, all samples were correctly classified, which represented a recognition ability of 100%. These results suggest that catechins and caffeine profiles of Yabukita green tea leaves could be useful to determine their growing areas in Japan.