Effect of Ingestion of the Japanese Persimmon 'Saijo' Fruit on Ethanol Levels in the Blood of Humans and Rats

The Japanese astringent-type persimmon 'Saijo' fruit is considered to contain bioactive compounds that help to alleviate the deconditioning seen after excessive intoxication with alcohol in humans. To evaluate the contribution of ingestion of persimmons in lowering blood ethanol levels in intoxicated humans, we investigated the blood ethanol concentration with the ingestion of persimmons (fresh or semi-dried persimmon fruit and persimmon extract) before or after alcohol consumption (including a comparison with that of apples before alcohol consumption) . For rats, we investigated their blood ethanol concentration with the ingestion of persimmon extract before alcohol administration, and also detected the antioxidant activity (measured as ferric reducing antioxidant potential (FRAP) ) and flavonoid content in their blood after administration of persimmon extract. Ingestion of persimmons before alcohol consumption significantly reduced human blood ethanol levels compared with control values 1 h after alcohol consumption, and this was even more effective than that observed with apple ingestion. Rat data also suggested the same tendency of persimmon extract, but the difference was not significant. There was no significant difference in the human blood level of ethanol between ingestion of persimmons after alcohol consumption and that of control. In addition, neither an increase in the level of flavonoids nor an increase in antioxidant activity were detected in rat plasma; there was even a slight decrease in FRAP after administration of persimmon extract. Taken together, these data showed that the functional compound kaki-tannin alone or together with other components in persimmon fruit ingested by humans before alcohol consumption was effective in lowering blood ethanol levels. These components are not entirely absorbed to blood capillaries, so they might adsorb the ethanol in the human digestive system to depress the absorption coefficient of ethanol on the surface of the gastrointestinal epithelium.