ABSTRACT
Aims: The crude methanolic flower extract of Polygonum lapathifolium (s.l.) (family: Polygonaceae) was to evaluate for its possible phytochemical constituents and selected pharmacological activities (anthelmintic and anti-emetic activity) growing in Bangladesh. Study Design: In vitro anthelmintic and in vivo antiemetic activities were evaluated by Pheretima posthuma model and chick emesis model respectively. Place and Duration of Study: Department of Pharmacy, Noakhali Science & Technology University, Noakhali, September, 2012 to December, 2012. Methodology: Phytochemical screening was done by characteristic color changes using standard procedures. In anthelmintic activity test, the parameters like: time of paralysis (vermifuge) was noted when no movement of any sort could be observed except when the worms were shaken vigorously. Time of death (vermicide) was determined by observing no movement when the worms were shaken vigorously or dipped in warm water (50ºC). The methanol extract was used at the concentration of 20, 40, 60, 80 and 100 mg/ml. Piperazine citrate (10 mg/ml) was used as standard reference. In anti-emetic test, sample extract was administered at a dose of 150 mg/kg orally and emesis was induced by copper sulphate (50 mg/kg orally). Metoclopramide (50 mg/kg .b.w intraperitoneally) was used as a standard drug. The antiemetic activity was determined by calculating the mean decrease in number of retching in contrast with those of control disorders. Results: The phytochemical investigation indicated the presence of alkaloids, phytosterols, diterpins, amino acids and proteins, flavonoids and phenolic compounds. The flower extract exhibited significant anthelmintic activity at a concentration of 40 mg/ml compared with standard reference. The flower extract also showed statistically significant antiemetic effect (85.42% inhibition) compared with reference drug which showed 81.25% antiemetic activity. Conclusion: So, the flower extract exhibited potential anthelmintic and anti-emetic properties, thus provide scientific basis for its use in folk medicine for the management of GI disorders. The plant may further be explored for its various pharmacological activities.