Kaleab Alemayehu Zewdie, Dayananda Bhoumik, Dawit Zewdu Wondafrash, Kald Beshir
Diarrhoea is a pass of watery stool at least three times or more in a day. Up to know there is no definitive drug to cure patients with diarrhoea, emergency of drug resistance to the conventional antibiotics makes the treatment of diarrhoea more challenging. Brucea antidysenterica is one of the several medicinal plants used traditionally for the treatment of diarrhoea. Hence, the aim of the present study is to investigate the antidiarrhoeal and antibacterial activities of the crude root extract and solvent fractions of B. antidysenterica. Plant material was collected and authenticated. It was washed, dried, pulverized, and then extracted by cold maceration using 80% methanol and fractionated with different solvents. The antidiarrhoeal activity was tasted using castor oil-induced diarrhoea, castor oil-induced charcoal meal test and castor oil-induced enteropooling models. Moreover, the antibacterial activity of the crude extract was conducted using agar well diffusion and broth micro dilution method. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were also determined. In the castor oil-induced diarrheal model, the crude extract, ethyl acetate and chloroform fractions significantly delayed the diarrheal onset at 200 and 400 mg/kg doses (p < 0.001) and they also inhibit the number and weight of faecal output at all tested doses as compared with the negative control. Results from the charcoal meal test revealed that the test extract showed a significant anti-motility effect (p < 0.001) at all test doses. Likewise, in the enteropooling test, it displayed a significant reduction in the weight and volume of intestinal contents at the doses of 200 and 400 mg/kg (p < 0.01). The highest concentration (800mg/mL) of test extract showed maximum antibacterial effect in all tested standard strains of bacteria (18.3 mm-22 mm). While MIC and MBC values (0.39 mg/ml and 1.56 mg/ml) indicated that S. flexneri was the more susceptible pathogen for test extract. All models revealed that the root extract of Brucea antidysenterica has strong antidiarrhoeal and antibacterial activities. Therefore, this finding provides scientific support for the acclaimed traditional use of Brucea antidysenterica as a treatment of diarrheal diseases and can serve as baseline data for further related studies