OBJECTIVETo investigate the intestinal absorption of naringin, hesperidin, neohesperidin and the extract of Fructus Aurantii Immaturus in rats.

METHODThe rat intestinal perfusion and enzymes incubation models were used, together with the determination of the n-octanol/water partition coefficient of the components (P).

RESULTIn perfusion model, the P(eff) of all components were low, and the P(eff) of naringin, hesperidin and neohesperidin were 0.140-0.252, 0.156-0.268 and 0.154-0.285, respectively. In four different regions of intestine of rat and with different concentration, the P(eff) of the components both had no significant difference, whereas the P(eff) of the extract were higher than the P(eff) of the single component. The metabolite of components was not detected in intestine. The P of naringin, hesperidin and neohesperidin were 0.36, 0.40 and 0.48, respectively, and the pH of buffer solution had no influence to its distribution coefficient.

CONCLUSIONPoor permeation contributed to the poor intestinal absorption of naringin, hesperidin and neohesperidin. The absorption of components in extract were increased, and the results suggest that the extract may enhance the intestinal absorption of the components.