Authors: Ruchi Upadhya, Varun Jain
Abstract: The escalating global threat of antimicrobial resistance has intensified the need for novel therapeutic agents derived from natural sources. Adhatoda vasica (Family: Acanthaceae), a traditional medicinal plant in Indian systems of medicine (Ayurveda and Unani), is widely used for respiratory and inflammatory disorders. This study evaluated the in vitro antimicrobial activity of ethanolic leaf extracts of A. vasica against common bacterial pathogens. Using the agar disc diffusion method, the extract demonstrated significant inhibition of Staphylococcus aureus (12.6 ± 0.4 mm), Escherichia coli (8.9 ± 0.3 mm), Klebsiella pneumoniae (10.7 ± 0.5 mm), and Candida albicans (13.1 ± 0.2 mm). Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined via broth dilution, revealing effective concentrations ranging from 62.5–250 µg/mL. Phytochemical screening confirmed the presence of alkaloids (vasicine), flavonoids, and tannins, aligning with reported mechanisms of antimicrobial activity. While the extract outperformed standard antibiotics in some cases, further in vivo studies and compound isolation are warranted to harness its therapeutic potential.
