ABSTRACT
Aims: The crude ethanolic leaf extract of Bacopa monnieri (L) Penn. (family: Scrophulariaceae) was evaluated for its possible phytochemical nature (group determination of plant constituent) and selected pharmacological activities (analgesic, antidiarrhoeal and cytotoxic activity) growing in Bangladesh. Methodology: The antinociceptive activity was evaluated by acetic acid induced writhing model, antidiarrhoeal activity by castor oil induced diarrheal method and cytotoxicity by brine shrimp lethality bioassay. Results: Phytochemical analysis of the ethanolic extract of B. monnieri indicated the presence of reducing sugar, tannins, steroid, alkaloid, saponin and gum types of compounds. The ethanolic extract of B. monnieri has effect on acetic acid induced writhing in mice. At the dose of 250 mg/kg and 500 mg/kg of body weight, the extract produced 36.69% and 59.17% writhing inhibition in test animals respectively. The results were statistically significant (p <0.01 and p <0.001) and was comparable to the standard drug Diclofenac Na, which showed 72.78% at a dose of 25 mg/kg weight. The ethanolic extract of B. monnieri has effect on castor oil induced diarrhea in mice. The result showed that the extract decreased the mean number of defecation which were 35.42 % and 47.92 % (p <0.001) at the doses of 250mg/kg and 500mg/kg respectively. The latent period for the extract treated group was increased (p <0.01) as compared to control group. The ethanolic of extract of B. monnieri showed significant toxicity to the brine shrimp nauplii. The concentrations of crude extract for 50% mortality (LC50) and 90% mortality (LC90) were 40 μg/mL and 150 μg/mL respectively. Conclusion: Therefore, the obtained results tend to suggest the antinociceptive, antidiarrhoeal and cytotoxic activities of crude ethanolic extract of Bacopa monnieri leaves and thus provide the scientific basis for the traditional uses of this plant part as a remedy for pain and diarrhoea.