Phytochemical investigations and antibacterial activity of some medicinal plants against pathogenic bacteria

The antibacterial activity of various solvent extracts of medicinal plants was evaluated against the human pathogenic bacteria Escherichia coli, Klebsiella pneumonia, Bacillus subtilis Bacillus cereus, Salmonella typhi, Enterobacter aerogenes and Staphylococcus aureus by agar cup diffusion method. Methanol extracts of Clerodendrum inerme L., Terminalia chebula Retz., Curcuma amada Roxb., Anacardium occidentale L., Duranta repens L., Eucalyptus camaldulenis Dehnh and Euphorbia cotinifolia L. showed significant activity. The petroleum ether and chloroform extracts of Terminalia chebula, Curcuma amada and Piper betel also showed promising results. The antibacterial activity of promising plant extracts when compared with standard drugs streptomycin and gentamycin recorded siginificant inhibition. Phytochemical analysis of the different extracts of the screened plants indicated the presence of flavanoids, terpinoids, tannins steriodas, alkaloids and glysocides. The positive results of screening of medicinal plants for antibacterial activity forms primary platform for further phytochemical and pharmacological studies.