Evaluation of the aqueous extract of Boswellia dalzielii stem bark for antimicrobial activities and gastrointestinal effects

Abstract

The aqueous extract of Boswelli dalzielii Hutch (family: Burseraceae) was investigated for therapeutic properties using aspirin-induced ulceration in rats, gastrointestinal motility in mice and castor oil-induced diarrhoea in rats. The median lethal dose (LD50) of the extract was carried out via the oral route in mice. Antimicrobial and preliminary phytochemical screening of the extract was also investigated. The extract did not show toxicity signs or death at doses < 2000 mg/kg p.o. The extract (50-200 mg/kg i.p.) dose dependently reduced acetylsalicylic acid (aspirin) (200 mg/kg p.o.) - induced ulceration in rats. The results obtained compared favourably with cimetidine (100 mg/kg i.p.). The extract (25-100 mg/kg p.o.) dose also dependently reduced intestinal propulsion of charcoal-treated mice. However, the extract (25-100 mg/kg i.p) did not produce significant (P >O.O5) protection against castor oil-induced diarrhoea in rats. No antimicrobial effects were shown by the extract (200 mg/kg) against any of the tested organisms. Tannins were detected in the aqueous extract. The above results show that B. dalzielii stem bark probably contains some active ingredients that could be developed for such gastrointestinal problems as have been claimed by traditional medical practitioners.             Key words: Boswellia dalzielii, peptic ulcer, gastrointestinal motility, diarrhoea, antimicrobial effects.