| Budget Amount *help |
¥1,700,000 (Direct Cost: ¥1,700,000)
Fiscal Year 1986: ¥300,000 (Direct Cost: ¥300,000)
Fiscal Year 1985: ¥300,000 (Direct Cost: ¥300,000)
Fiscal Year 1984: ¥1,100,000 (Direct Cost: ¥1,100,000)
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| Research Abstract |
Chemical examinations on tannins and related compounds in Chinese crude drugs (rhubarbs and cinnamon barks), beverage teas (green tea, oolong tea and black tea) and several plant materials (Punica granatum, Quercus stenophylla, Elaeocarpus sylvestris var. ellipticus, Kandelia candel, Dioscorea cirrhosa and Salix sieboldiana) have been made. From several commercial rhubarbs, three new flavan-3-ols, three procyanidin glucosides, one proanthocyanidin and seven dimeric procyanidin gallates were isolated and structurally elucidated. Chemical studies on five commercial cinnamon barks produced from Kannan, Tohko, Viet-Nam, Ceylon and Japan yielded lots of proanthocyanidins, among which the isolation of two sweet-taste trimers is of great interest. Quantitative determination of procyanidins in these cinnamons was also made by HPLC combined with the ordinary hide powder method, and it has become clear that the contents and compositions of the procyanidins differ remarkably in each cinnamon. Examination of three types of commercial teas led us to the isolation and characterization of more than fourty polyphenols in total, and comparison of their patterns and contents in these teas has clearly demonstrated the oxidaiton pathways of tea phenols in the fermentation steps. On research into polyphenols in the leaves and bark of Punica granatum, we have isolated twenty hydrolyzable tannins including six new and two structurally revised compounds. The leaves of Elaeocarpus sylvestris var. ellipticus yielded a novel and biogenetically important ellagitannin, elaeocarpusin possessing the structure in which ascorbic acid and geraniin are connected. We have isolated and structurally determined sixty-eight phenolics (including thirty-nine new compounds) from Quercus stenophylla and totally fifty-one proanthocyanidins (including twenty-eight new compounds) from the above-mentioned plants (K. candel, D. cirrhosa and S. sieboldiana) growing in Taiwan.
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