Abstract

The anti-diarrheic effects of the methanolic leaf extract of Palisota hirsuta (LEP) were evaluated using castor oil-induced diarrhea model and charcoal meal model to evaluate small intestinal transit (SIT). The plant material was extracted using cold maceration with 70% methanol for 48 h and concentrated in vacuo and was fractionated using column chromatography. LEP yielded 8.77% w/w material and seven fractions after column chromatography. LEP (100 mg/kg) significantly (P < 0.05) decreased total number of fecal output 3 h post-administration of castor oil compared with the 10 ml/kg distilled water treated group (negative control) and caused 46% inhibition of diarrhea compared with diphenoxylate (reference drug). The SIT was significantly (P < 0.05) decreased by all doses of LEP used (50, 100, 150 mg/kg), when compared with the negative control and caused 4% inhibition of intestinal fluid accumulation at 50 mg/kg compared with diphenoxylate. LEP fraction 2 (50 mg/kg) caused significant (P < 0.05) decrease in SIT compared with the negative control and caused 2% inhibition of intestinal fluid accumulation compared with diphenoxylate. The major phytochemical constituents of LEP fraction 2 were tannins. The methanolic leaf extract of P. hirsuta showed promising anti-diarrheic properties, possibly mediated by tannins, thus providing basis for its traditional use as an anti-diarrheic agent.

Key words: Palisota hirsuta, anti-diarrhea, small intestinal transit, fluid accumulation.

Abbreviation

LEP, Leaf extract of Palisota hirsute; LEPfr, leaf extract of P. hirsuta fraction; SIT, small hirsuta intestinal transit; FA, fluid accumulation.