title: [Functional saponins in tea flower (flower buds of Camellia sinensis): gastroprotective and hypoglycemic effects of floratheasaponins and qualitative and quantitative analysis using HPLC].
abstract: As a part of our characterization studies on the bioactive saponin constituents of tea flowers (Camellia sinensis, flower buds), the methanolic extract and 1-butanol-soluble portion (the saponin fraction) from the flower buds were found to exhibit potent inhibitory effects on ethanol- and indomethacin-induced gastric mucosal lesions in rats and on serum glucose elevation in sucrose-loaded rats. Among the constituents of the 1-butanol-soluble portion, floratheasaponins A, B, and C showed gastroprotective and hypoglycemic activities. Furthermore, we have developed qualitative and quantitative methods using HPLC for the principle saponins, floratheasaponins A-F, in tea flowers, which were previously found to show antiallergic and antiobesity effects. Using those methods, the saponin composition of Indian tea flowers were found to be similar to those of Chinese (Anhui) but not of Japanese tea flowers. On the other hand, it was found that the floratheasaponin contents in tea flowers varied markedly during the blooming period, and they were abundant at half-bloom. Additionally, the contents of caffeine in the tea flowers were examined using HPLC.
authors.affiliation: Kyoto Pharmaceutical University, shityono-cho, Misasagi, Yamashina-ku, Kyoto, Japan. myoshika@mb.kyoto-phu.ac.jp
authors.forename: Masayuki
authors.initials: M
authors.lastname: Yoshikawa
authors.forename: Tao
authors.initials: T
authors.lastname: Wang
authors.forename: Sachiko
authors.initials: S
authors.lastname: Sugimoto
authors.forename: Seikou
authors.initials: S
authors.lastname: Nakamura
authors.forename: Akifumi
authors.initials: A
authors.lastname: Nagatomo
authors.forename: Hisashi
authors.initials: H
authors.lastname: Matsuda
authors.forename: Shoichi
authors.initials: S
authors.lastname: Harima
mesh_terms: D000818:Animals; D028241:Camellia sinensis / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D035264:Flowers / Q000737:chemistry*; D006943:Hyperglycemia / Q000188:drug therapy*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D017208:Rats, Wistar; D012503:Saponins / Q000032:analysis / Q000302:isolation & purification* / Q000627:therapeutic use*; D013276:Stomach Ulcer / Q000517:prevention & control*
chemical_list: D012503:Saponins