The in vitro antidiarrhoeal activity of Holarrhena antidysenterica (bark) wall extracts
The in vitro antidiarrhoeal activity of ethanolic (by maceration) & aqueous (by soxhlet) extracts of the bark of Holarrhena antidysenterica and its comparison with that of standard drugs was evaluated. It showed significant activity against Shigella boydii, Shigella soneii and Shigella flexneri whereas the activity of both extracts was found to be moderate against Shigella dysenteirae. The minimum inhibitory concentration (by micro dilution) against the strains of Shigella was recorded between 250 to 500µg/ml. Viable cell count method was also used to decipher bactericidal or bacteriostatic action of each extract. All the extracts were bactericidal within 2h. The extract was found to be more effective than the standards at lower end of the concentrations tested (0.5mg/ml and 1.0mg/ml). The antimicrobial activity of the extract is comparable to standard antibiotic ciprofloxacin.
The results support the efficacy of ethanolic and aqueous extracts of bark of Holarrhena antidysenterica as bacteriocidal and antidiarrhoeal agent. Our present work suggests that preclinical and clinical trials of both aqueous and alcoholic extracts of the stem bark of Holarrhena antidysenterica can be carried out against different enteric pathogens, causative agents of diarrhoea in population.
References:  Ahmad, I. et al. (1998)J. Ethnopharmacol. 62:183–93.
 Ballal, M. et al. (2001) Indian J. Pharmacol. 33:392–393.