Differences in caffeine, flavanols and amino acids contents in leaves of cultivated species of Camellia.

Abstract

Caffeine, flavanols and amino acids in the frst flush shoot leaves of 23 species belonging to the genus Camellia were assayed by gas and high performance liquid chromatography Based on these results, principal component analysis was performed. Camellia sinensis and C.taliensis of section Thea contained caffeine, five flavanols (catechins) and theanine (the most abundant amide in tea), whereas C.irrawadiensis of the same section was characterized by the absence of caffeine. Chemically, C.taliensis was closely related to C.sinensis. Most species in sections other than Thea did not contain detectable amounts of caffeine or theanine, except for a clone of C.kissi of section Paracamellia that contained a small amount of caffeine and C.furfuracea of section Heterogenea which contained theanine. An approximate correlation of the flavanol patterns with subgeneric sections was made. ECG (epicatechin gallate) and EGCG (epigallocatechin gallate) were present in only the plants of section Thea. In most of the species studied, the EC (epicatechin) content was higher than that of (+)-C ((+)-catechin), but in four species, C.furfurabea and C.granthamiana of section Heterogenea, and C.oleifera of section Paracamellia and C.japonica subsp. hozanensis of section Camellia, (+)-C w, as the predominant flavanol. The flavanol gas chromatograms of C.sasanqua, C.saluenensis and C.japonica subsp. hozanensis showed 4 marked peaks derived from unidentified components.