Studies on the Antidiarrhoeal and Antimicrobial Effect of the Methanol Extract of harungana madagascariensis Leaves.

Abstract

Harugana.madagascariensis leaf is a rich source of flavonoid saponin,carbohydrates ,terpenoid, steroids, phenolics,tannin and has been reported to have medicinal property as well as some physiological potentials. This study evaluated the antidiarrhoeal and antimicrobial activity of methanol extract of Harugana madagascariensis leaves. The qualitative phytochemical constituents of the extract showed the relative presence of flavonoids in relatively high concentration, tannins, reducing sugars, steroids, phenols, alkanoids, terpenoids and saponins in moderately high concentration, whereas soluble carbohydrates, glycosides and hydrogen cyanides were in low concentration. The median lethal dose (LD50) of the extract recorded no death at the highest dose of 5000 mg/kg b.w. In the castor oil induced diarrhoea, the group treated with 50 and 200 mg/kg b.w of extract had significantly (p < 0.05) reducced wet feacal droppings when compared with positive control (group 2). Group treated with 100 mg/kg b.w(p.o) was significantly (p < 0.05) higher wet feacal droppings at 1 hr when compared to 4 hr. The wet feacal dropping of the group treated with 100mg/kg b.w (p.o) of extract was observed to be non-significantly (p > 0.05) lower when compared with positive control. Group treated with 200 mg/kg b.w (p.o) of extract was significantly (p < 0.05) higher wet feacal droppings at 1hr when compared with 4hrs. In the castor oil-induced enteropolling assay in rats, all the treatrd groups (50 -200) mg/kg b.w of extract non-significantly (p > 0.05) decreased the intestinal fluid accumulation when compared with group 2 (positive control). The treated groups (50-200) mg/kg b.w extract reduced the fluid accumulation in a dose dependent manner with a percentage inhibition of 10.09%, 19.74%, and 27.63% respectively. The result of the methanol extract of H .madagascariensis on weight of the intestinal contents of the castor oil-inducced enteropoling showed a non-significant increase (P > 0.05) in group 2 and 5 rats administered 50 and 100 mg/kg b.w of the extract when compared with positive control while the weight of the intestinal contents for the group treated with 200 mg/kg b.w(p.o) was significantly (P < 0.05) lower when compared with group 2 ( positive control). The effect was observed to be in a dose dependent manner in all the treated groups (50-200) mg/kg b.w extract reducing the weight of intestinal content with percentage inhibition of 18.82%, 27.53%, and 50.59% respectively. The result of methanol extract of H.madagascariensis on gastrointestinal transits showed that the intestinal motility effect of the extract at all the tested doses (50-200) mg/kg b.w extract was significantly (p < 0.05) lower when compared with group 2 (positive control). The K+, Na+, HCO3- and Cl- ion concentration of all the treated groups was significant (p < 0.05) higher when compared with group 2 (positive control). The creatinine and urea level of the group treated with 50, 100 and 200 mg/kg b.w of extract was significantly (p < 0.05) lower when compared with positive control. There was a decrease (p < 0.05) in sensitivity of methanol extracts of H.madagascariensis in all the tested organism when compared with standard drug (ciprofloxacin).The result showed that standard drug (ciproflaxacin) produced the least minimum inhibitory concentration (MIC) in all the bacteria samples. The MBC on all the tested organisms were also found to be higher for the extract when compared with the standard drug.