ABSTRACT

Boerhavia dffusa is a perennial herbaceous plant; member of the family Nyctaginaceae. It is widely distributed in the tropics and subtropics. The aims of this work were to evaluate the phytoconstituents, antioxidant and antidiarrheal potential of methanolic extract of Boerhavia c4ffiisa leaf. Fresh leaves of B. diffussa were collected from Umugbalu in Ikwuano Local Government Area of Abia State, South Eastern Nigeria. The in vitro antioxidant activities were determined using nitric oxide scavenging assay, 2,2—diphenyl-1-picrylhydrazyl (DPPH) and the ferric reducing antioxidant power (FRAP) Assays. Phytochemical spot test was used to determine the phytoconstituents. The antidiarrheal potential of B. dffusa extract (BDE) was determined using the castor oil induced diarrhea, intestinal accumulation (enteropooling) and the small intestinal transit models. The phytochemical test showed the presence of tannins, saponins, flavonoids, glycosides and terpenes at low concentration. The BDE produced concentration dependent nitric oxide scavenging activity which was significantly (p <0.05) lower when compared with ascorbic acid. The BDE produced concentration dependent DPPH radical scavenging activity which was significantly (p <0.05) reduced when compared with ascorbic acid. BDE at 25, 50 and 100 p.g/ml concentration, produced no activity on FRAP assay, while at 200 and 400 g/ml concentration it didn't produce a significant effect when compared to the ascorbic acid. In the castor oil induced diarrhoea, loperamide (5 mg/kg) and BDE (50, 100 and 200 mg/kg) produced significantly (p <0.05) lower percentage of wet feaces when compared with distilled water treatment at 1 hour. At 2 h post diarrhea induction, loperamide and BDE (100 mg/kg) caused significant (p < 0.05) percentage reduction in the number of wet feaces in the treated groups when compared with distilled water treated group. At 3 and 4 h post diarrhea induction, only loperamide produced significant (p < 0.05) decrease in the percentage wet feaces when compared with distilled water treated group. The volume of the intestinal content of the extract (50, 100 and 200 mg/kg) treated groups were not significantly (p > 0.05) reduced when compared with distilled water treated group. The percentage intestinal charcoal meal transit of loperamide and BDE 50 mg/kg treated group is significantly (p < 0.05) reduced when compared to distilled water treated group. BDE at all concentrations in the presence of acetyicholine produced significant anti cholinergic effects on the jejunum of the rabbit. The study showed that methanol extract of boerhavia diffusa contained tannins, saponins, flavonoids, glycosides and terpene that validated the use of B. diffusa in the ethnobotanical management of diarrhoea.