Abstract

Methanol extract of the leaf of Heliotropium indicum was evaluated for its antimicrobial activity against five bacterial isolates comprising of four Gram-negative namely: Escherichia coli, Pseudomonas aeruginosa, Klebsiella spp. and Proteus mirabilis; and one Gram positive, Staphylococcus aureus at 6.25, 12.5, 25, 50, 100 and 200 mg/ml including phytochemical analysis. While both S. aureus and Klebsiella spp. were inhibited at 50, 100 and 200 mg/ml with minimum inhibitory concentration (MIC) of 3 mg/ml; P. aeruginosa and P. mirabilis with MIC of 10 mg/ml were inhibited at 100 mg/ml and 200 mg/ml. E. coli with MIC of 20 mg/ml was inhibited only at 200 mg/ml concentration of the extract. Phytochemical analysis revealed the presence of plant metabolites as alkaloids, saponin and tannins. While activity-directed assay is advocated, the plant promises to be of tremendous assistance in the treatment of infections with which bacterial isolates used for the study are associated. 

Key words: Phytochemical, antimicrobial, Heliotropium indicum alkaloids, saponin, tannin.