Objective: The present study was designed to evaluate the phytochemical composition and antibacterial and antioxidant potential of methanolic leaf and root extracts of Indigofera tinctoria L.Methods: Phytochemical analysis was done using standard methods. The methanolic leaf and root extracts of the plant were tested against Staphylococcus aureus, Enterococcus faecalis, Klebsiella pneumoniae, Enterobacter aerogenes, and Salmonella paratyphi B by cup-plate agar diffusion method. The free radical scavenging activities of the methanol extracts of leaves and roots were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay.Results: Phytochemical screening revealed the presence of carbohydrates, reducing sugars, alkaloids, saponins, phenolic compounds, and flavonoids in methanolic leaf and root extracts. Methanolic leaf extracts of the plant exhibited antibacterial activity against a wide range of bacteria, but the root extracts failed to inhibit the tested bacterial pathogens. The antioxidant activity determination revealed that at 100 μg/ml, methanolic root extracts had the highest antioxidant activity (89.10%) on DPPH free radicals followed by methanolic leaf extracts (46.74%).Conclusion: The results of the present study conclude that the studied plant possesses broad-spectrum antibacterial and antioxidant properties and may act as a potent antioxidant for biological systems susceptible to free radical-mediated reactions.

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Withania somnifera (L.) Dunal commonly known as 'Ashwagandha' is a widely used herb in Ayurvedic medicine.In the present study, root extracts of Withania somnifera were analysed for phytochemical constituents, and antimicrobial property. Antibacterial activity of root extract was tested by agar-well diffusion method against Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa and Salmonella paratyphi B. The study also investigated the effect of temperature on its antibacterial activity. Qualitative phytochemical analysis revealed the presence of carbohydrates, reducing sugars, alkaloids, phytosterol, fixed oils, proteins, phenolic compounds and flavonoids. All the bacterial strains were found to be sensitive to acetone, ethyl acetate and ethanol extracts. Acetone and ethanol extracts were more effective against Klebsiella pneumoniae, whereas ethyl acetate extract was more effective against Pseudomonas aeruginosa and Salmonella paratyphi B. The effect of temperature on the antimicrobial potential of the root extracts of the plant remained reasonably unaffected. The present screening demonstrated that Withania somnifera root extract has potent antibacterial activity and a potential source of new class of antimicrobial compounds that could be useful for infectious disease chemotherapy and control.