A partially purified tannin was prepared by a K₂HPO₄-precipitation method from immature persimmon fruit (Diospyros kaki L., cv. “Hiratanenashi, ” astringent type). The kaki-tannin gave deiphinidin and cyanidin on acid hydrolysis. Its methylated derivative showed v_max 1720cm^-1 in IR spectrum and had the molecular weight of ca. 1.38×10⁴ daltons in Mw. From the results of toluene-α-thiol treatment, it is suggested that the kaki-tannin consists of catechin, catechin-3-gallate, gallocatechin, gallocatechin-3-gallate and an unknown terminal residue, and belongs to proanthocyanidin B group with a carbon-carbon interfiavan linkage from C-4 of one unit to C-6 or C-8 of another unit.

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