Journal of Ethnopharmacology 69 (2000) 63 – 71 Short communication Antibacterial activity of some folklore medicinal plants used by tribals in Western Ghats of India R. Perumal Samy, S. Ignacimuthu * Entomology Research Institute, Loyola College, Chennai 600 034, India Received 10 May 1998; accepted 28 August 1998 Abstract A series of 30 Indian folklore medicinal plants used by tribal healers to treat infections, were screened for antibacterial properties at 10 mg/ml concentration by using disc diffusion method against Bacillus subtilis, Escherichia coli, Klebsiella aerogenes, Proteus ulgaris, Pseudomonas aerogenes and Staphylococcus aureus. Twenty plant species showed activity against one or more species of bacteria used in this assay; among them the leaf extracts of Cassia occidentalis and Cassia auriculata exhibited significant broad spectrum activity against B. subtilis and S. aureus. Ten plant species were not found active against all tested bacteria. These results were compared with results obtained using standard antibiotics, chloramphenicol (30  g/disc) and streptomycin (30  g/disc) which served as a reference for inhibition zone diameter © 2000 Elsevier Science Ireland Ltd. All rights reserved. Keywords: Antibacterial; Folklore medicine; Tribals; Plant extracts www.elsevier.com/locate/jethpharm 1. Introduction In many countries such as India and China, where thousands of tribal communities still use folklore medicinal plants today to cure sicknesses. The great interest in the use and importance of Indian medicinal plants by the World Health Or- ganisation in many developing countries has led to intensified efforts on the documentation of ethnomedical data of medicinal plants (Dhar et al., 1968; Waller, 1993; Perumal Samy and Patri- craja, 1996). It is a necessity from the scientific point of view, to establish a rational relationship between chemical, biological and therapeutical ac- tivities of folklore medicine (Levin, 1976; Coley and Aide, 1991; Gentry, 1993). Biologically active compounds from natural sources has always been of great interest to scientists working on infectious diseases. In recent years there has been a growing interest to evaluate plants possessing antibacterial activity for various diseases (Clark and Hufford, 1993). A number of studies have been reported, dealing with antimicrobial screening of extracts of medicinal plants (Malcom and Sofowora, 1969; Bhakuni et al., 1974; Taniguchi et al., 1978; * Corresponding author. 0378-8741/00/$ - see front matter © 2000 Elsevier Science Ireland Ltd. All rights reserved. PII S0378-8741(98)00156-1