Int. J. Med. Arom. Plants, ISSN 2249 – 4340 RESEARCH ARTICLE Vol. 2, No. 1, pp. 123-134, March 2012 *Corresponding author: (E-mail) sk_dutta<A.T.>yahoo.com http://www.openaccessscience.com ©2012 Open Access Science Research Publisher ijmap@openaccessscience.com Anti-diarrheal activities of medicinal plants of Similipal Biosphere Re- serve, Odisha, India Sujogya Kumar PANDA 1 , Niranjan PATRA 1 , Gunanidhi SAHOO 2 , Akshya Kumar BASTIA 3 , Sushil Kumar DUTTA 2 * 1 Department of Biotechnology, North Orissa University; Baripada, India-757003 2 Department of Zoology; North Orissa University; Baripada, India-757003 3 Department of Botany; North Orissa University; Baripada, India-757003 *Corresponding Author, Fax: + Tel: +91-9437143598, Fax: +91-6792253908 Article History: Received 17 th September 2011, Revised 23 rd January 2012, Accepted 23 rd January 2012. Abstract: This paper deals with ethnomedicinal uses and anti-diarrheal properties of medicinal plants used by the tribal people of District Mayurbhanj, Odisha, India. Aqueous and methanol extracts of 72 plants were tested for antibacterial activity using agar well diffusion (sample concentration of 100 mg/ml) against eight pathogenic bacteria responsible for diarrheal diseases. The results indicated that out of 77 plants species, 47 species exhibited antibacterial activity against one or more test organisms. Out of 168 extracts, 54 methanolic and 43 aqueous extracts expressed antibacterial proper- ties. Nineteen plants are newly reported to have ethnomedicinal uses to treat diarrheal diseases. Among these, Bombax ceiba, Buchanania lanzan, Butea superba, Coccinia grandis, Curculigo orchioides, Eleutherine bulbosa, Ficus racemo- sa, Flemingia nana, Helicteres isora, Lannea coromandelica, Mesua ferrea, Semecarpus anacardium and Smilax zeyla- nica experimentally proved to inhibit the diarrhea causing bacteria. Salmonella typhi, Escherichia coli and Vibrio cholera were the most sensitive strain. Shigella dysentriae showed least activity compared to all other test strains. Keywords: Anti-diarrheal; Similipal Biosphere Reserve; Preliminary screening; Plant extracts; Ethnomedicinal uses. Introduction Diarrhea, particularly infectious diarrhea is the second leading cause of mortality and mor- bidity throughout the world in children less than 5 yrs of age. This is especially true in develop- ing countries like India where there is poor sani- tation and overcrowding. Estimation of crude death rate due to diarrhea in India was 9.3 per 1000 population (WHO 2005). If this continues, then the predicted case of burden will rise to 126.35 cores during 2016 (WHO 2005). Among the leading causes of infectious diarrhea, Sal- monella and Shigella contributes highest num- ber. The current chemotherapeutical treatment of Salmonellosis and Shigellosis is complicated as a result of drug resistance. Moreover, majori- ty of the people in these developing countries have no access for modern health care facilities. This necessitated the search for alternative ther- apies such as, the use of medicinal plants. Shi- gellosis is an important cause of diarrheal deaths. It has been reported that not less than 140 million cases of Shigellosis occur world- wide with 6,00,000 deaths annually, 60% of such deaths are of under 5 years old children (Peirano et al. 2006; Sur et al. 2004). Among the different species of Shigella, S. dysentriae is known for its fatality, and life threatening situa- tion. The emergence of multiple drug resistant strains of diarrheagenic pathogens has made the treatment of dysentery more difficult hence there is increasing interest in plants as source of antimicrobial agents for the treatment of such diseases (Munshi et al. 1987; Monroe and Polk 2000). Salmonellosis, another type of diarrheal diseases is caused by a group of bacteria called Salmonella. It is primarily transmitted through ingestion of contaminated food by infected faeces from man or animal, through fecal oral route. Active cases of Salmonella in man are