Antibacterial Activity of Isolated Compounds from Allophylus spicatus (Poir.) Radlk (Sapindacea)

Abstract Phytochemical investigation on the roots of Allophylus spicatus (Sapindacea) led to the isolation of four compounds, namely cleomiscosin A (1), cleomiscosin C (2), scopoletin (3) and 3-oxotirucalla-7,24-dien-24-oic acid (4). The structures of the compounds were established by spectroscopic analysis: UV, IR, 1D and 2D NMR, EI-MS and HR-EI-MS and compared with the literature. These compounds are reported for the first time from the plant. The compounds showed potent antibacterial activity, marked inhibition against most of the tested bacterial strains: Pseudomonas aeruginosa (ATCC 27853), Escherichia coli (ATCC 25922), Salmonella typhi (ATCC 25923), Klebsiella pneumonia (ATCC 13883), Streptococcus faecalis (ATCC 29212) and Micrococcus luteus (ATCC 10240), with a zone of inhibition between 0.7±0.35 - 16±0.46 mm as compared with the zone of inhibition of Streptomycin (20±0.34 - 31±0.29 mm), a known antibacterial drug used as the standard. The antibacterial activity of the isolated phytochemicals could be responsible for the plant ethno-medicinal uses. GRAPHICAL ABSTRACT