Phytochemical Screening, Antibacterial and Antioxidant Activity of Senna Alata Leaf Extract

Medicinal plants are gaining acceptance globally, Senna alata being one of the many that herbal practitioners are using to cure a wide range of diseases. This study is aimed to determine the antibacterial effect of Senna alata on multidrug resistant strains of Pseudomonas aeruginosa and Staphylococcus aureus and to determine its antioxidant activity. Cold, Hot aqueous and 80% Methanolic extracts of Senna alata were used for the analysis. Kirby-Bauer disc diffusion method, Agar Well Diffusion (AWD), Minimum Inhibitory Concentration (MIC), and Minimum Bactericidal Concentration (MBC) techniques according to established standards were used to analyze the antibacterial property of the plant extracts on clinical isolates. Antioxidant studies of the Methanol extract component were carried out using 2,2-di-phenyl-1-picrylhydrazyl (DPPH), Total Oxyradical Scavenging Capacity and the Total Phenolic Content of the extracts were estimated. The 80% Methanolic extract showed a better mean diameter zone of inhibition at a statistically significant difference of P<0.05 than the cold and hot aqueous extracts, with a DZI value as high as 17±0.61 at a concentration of 400mg/ml. The MBC/MIC ratio was 2. The phytochemical analyses revealed an abundance of flavonoids, tannins and cardiac glycosides. The antioxidant activity showed abundance of phenols and the IC50 was 1.22 and 2.34 for DPPH and TOSC respectively. This study proves the antibacterial property of Senna alata, thus justifying its use among the local herbal practitioners. It is hereby recommended that more researches be carried out on Senna alata to establish its safety in human tissues.