Further Identification of Flavonoids Deposited in the National Museum of Nature and Science in Japan―Flavonoids Isolated from the Flowers of Cacti―

抄録

Further identification of 28 flavonoid powder and crystal samples which are deposited in Department of Botany, National Museum of Nature and Science, Japan were performed by UV, LC-MS, and HPLC comparisons with authentic samples. They were isolated from the flowers of 21 cactus species by one of the authors (T. Iwashina) in 1978–1983. Almost samples were identified as quercetin 3-O-rhamnosyl-(1→6)-glucoside (rutin) which has previous been partially characterized as quercetin 3-O-rhamnosylglucoside. Other some samples were identified as quercetin 3-O-galactoside (hyperin), rarely isorhamnetin and kaempferol 3-O-rutinosides and 3-O-robinobiosides, and quercetin 3-methyl ether 7-O-glucoside. Although quercetin 3-O-galactoside has been reported by Iwashina and Ootani (1986), it was shown by HPLC survey in this survey that small amount of quercetin 3-O-glucoside (isoquercitrin) of which the presence was not shown in previous reports was accompanied in all samples of hyperin. Flavonoids in the flowers of Tephrocactus ferocior, Lobivia atrovirens, Rebutia paraguaiensis and Epiphyllum hybrida were reported in this survey for the first time.