Abstract

The antibacterial screening of Celosia leptostachya Benth leaves was carried out using the agar well diffusion technique and the methanolic extract of the leaves showed considerable activity on Escherichia coli and Staphyllococcus aureus both at 60 and 80 mg/ml with zones of inhibition of 15.50, 18.00 and 16.50, 19.00 mm respectively. Whereas, it showed activity only at a concentration of 80 mg/ml with a zone of inhibition of 17.50 mm on Salmonella typhi. However, the C. leptostachya Benth extract showed no activity on Shigella dysentriae.The phytochemical properties of the extract were also determined. The result reveals the presence of alkaloids, flavonoids, cardiac glycosides, and tannins, whereas phlobatannins, anthraquinones, steroids and saponins were not detected in the extract. The extract containssome major bioactive compound that inhibit the growth of microorganisms thereby proving very effective as alternative source of antibiotics.

Key words: Phytochemical, antibacterial, methanolic extract, Celosia leptostachya Benth.