UTTAR PRADESH JOURNAL OF ZOOLOGY

This study is to analyse the antibacterial activity of ethanolic extracts of Clerodendrum infortunatum L. (Lamiaceae) and Vanda spathulata (L.) Spreng. (Orchidaceae) were investigated against Escherichia coli and Klebsiella sp. Disc diffusion method was adopted to determine antimicrobial activity against two microorganisms and 1.2% DMSO, Gentamycin and Ampicillin were used as control. The selection of extract was based on a phytochemical screening for the presence of secondary metabolites. The ethanolic extracts of C. infortunatum and V. spathulata showed the presence of alkaloids, tannins, saponins, triterpenoids, and cardiac glycosides. C. infortunatum and V. spathulata showed zone of inhibition against the two bacterial strains. The ethanolic extract of V. spathulata showed the maximum inhibition zone against Klebsiella sp. compared to C. infortunatum and higher zone of inhibition than antibiotic ampicillin. C. infortunatum has high zone of inhibition (10.3±0.47) against E. coli and V. spathulata has higher zone of inhibition (15.6±0.47) against Klebsiella sp. The results of this study showed that ethanolic extracts of C. infortunatum and V. spathulata used against E. coli and Klebsiella sp. has antibacterial activity. Although the use of these plants as antibacterial agents require extraction of its active compound and further explorations, these plants show promising antibacterial properties.