Studies on the Tannin of Japanese Persimmon (Diospyros KakiL.)

Kaki tannin was isolated from methanol extracts of unripe kaki fruit (Japanese persimmon) and it was found that a main constituent composing kaki tannin was a leucoanthocyanin. Its acetate and methyl ether were prepared and their properties and reactions were studied. From the results of these experiments, kaki tannin was presumed to be a (+) leucodelphinidin-3-glucoside (5,7,3′,4′,5′-pentahydroxyflavan-3,4-diol-3-g1ucoside).