Antidiarrhoael and antimicrobial effects of ethanol root bark extract from Salacia lehmbachii

Introduction: The roots of Salacia lehmbachii are used in Nigerian folklore medicine without scientific basis. The present study was aimed to investigate the antidiarrheal and antimicrobial activities of the ethanol extract of S. lehmbachii root bark. Methods: The antidiarrheal activity was examined using castor oil induced diarrhoea method. The ethanol root bark extract effects on intestinal transit time and enteropooling were also evaluated in rats, while antimicrobial activity was conducted on selected microorganisms. The acute toxicity test and phytochemical screening of the extract were also carried out. Results: The extract produced significant (P < 0.05) dose dependent protection on rats against castor oil induced diarrhoea. The extract inhibited intestinal transit time and caused significant dose related inhibition of castor oil induced enteropooling in rats, comparable to the standard drug, atropine (P < 0.05). The root bark extract significantly and dose dependently delayed the onset of castor oil induced diarrhoea, reduced the frequency of defecation and decreased the severity of diarrhoea in rats. S. lehmbachii ethanol root bark extract significantly and dose dependently decreased the volume of intestinal fluid accumulation in the castor oil induced enteropooling. The extract also significantly inhibited the growth of test organisms. The acute toxicity test produced no lethality in rats, whereas the phytochemical analysis revealed the presence of alkaloids, saponins, tannins, flavonoids, terpenoids, steroids, cardiac glycosides, resins and balsam. Conclusion: The results of this study confirm the ethnomedicinal use of S. lehmbachii root bark as a valuable natural agent for the treatment of diarrhoea and microbial infections.