Phytochemical screening and antibacterial activity of leaf extracts of <i>Senna siamea</i> (LAM) on <i>Pseudomonas aeruginosa</i>

Abstract

The anti-pseudomonal activities of aqueous, chloroform and ethanolic extracts of leaf of Senna siamea (LAM) were evaluated by agar disc diffusion method. This was with the aim of substantiating the ethnomedicinal use of the plant as anti-bacterial. All the extracts were not active to Ps. aeruginosa at the concentration levels of 100μg/disc and 200μg/disc, however the extracts were active at high concentration levels of 500μg/disc and 1000μ/disc revealing a dose – dependent antibacterial activity. Aqueous extract was the most active with zone diameter of inhibitions of 16mm and 30mm followed by ethanolic extract which had zones of inhibition of 10mm and 16mm and the least was chloroform extract which has zone diameter of inhibitions of 08mm and 14mm, all at 500μg/disc and 1000μg/disc concentrations respectively. Ciprofloxacin (oxoid) as positive control had zone diameter of inhibition of 35mm in all the test plates. The antipsedomonal potential of the leaves of Senna siamea Lam leaf may be due to the phytochemical compounds present in the leaf extracts, which were found to be tannins, saponnins and steroids. However aqueous extract proved to be a more suitable candidate for use in the treatment of diseases cause by Pseudomonas aeruginosa. Hence, antimicrobial evaluation and biotechnological study of the whole plant are thus recommended.

Keywords: Antipseudomonal, Senna siamea, Phytochemicals. Screening, Pseudomonas aeruginosa