In-Vitro Anti-Bacterial, Phytochemical and Antioxidant Activity of Gezawa (Withania somnifera (L.) Dunal) Extracts Against Human Pathogenic Bacteria

Withania somnifera (L.) Dunal is frequently used as traditional medicine for the treatment of numerous diseases. This study was aimed to assess bioactive compounds, antimicrobial activities and antioxidant studies on different part of W. somnifera. The plant parts were shaded dried and grinded to powders for biological activities. The ethanol, methanol and chloroform extracts were tested for antimicrobial activities. The extracts were subjected to a test of their antimicrobial properties by paper disc diffusion method. Minimum inhibitory concentrations (MICs) of the plant extracts against selected pathogens were also assessed using the agar dilution method. The highest potential was observed from methanol extract of the stem bark and ethanol extract of the leaf against Staphylococcus aurous with zone of inhibition 15.02 and 13.22 mm, respectively. Alkaloids, steroids, saponins, tannins, reducing sugars, phlobatanins, flavonoids, terpenoids, cardiac glycosides, anthraquinone, emodins and coumarins are result of phytochemical assessment. Strong antioxidant effect of free radical scavenging activity was recorded at 100µg/ml concentration for ethanol stem and root, methanol leaf extracts (72.22%, 80.84%, 74.24%) respectively. Chloramphenicol and DMSO were used as positive and negative controls. W. somnifera could show powerful antimicrobial and antioxidant properties.