Phytochemical evaluation, antioxidant, and antibacterial activity of extracts of Ammi visnaga Lam

This study aimed to identify chemical components and evaluate the antioxidant and antibacterial activities of ethanolic and dichloromethane extracts of Ammi visnaga (L.). Both extracts contained flavonoids, coumarins, and glycosides, with the ethanolic extract also exhibiting tannins and reducing sugars. Qualitative HPLC/UV-ESI-MS analysis revealed abundant polyphenols, particularly flavonoids and furanochromones, such as rhamnazin, kaempferol, rhamnetin, khellin, visnagin, khellinin, and khellol. Antimicrobial activity against Gram-positive and Gram-negative bacteria was assessed, with Klebsiella pneumoniae showing sensitivity to the ethanol extract, resulting in a 9 mm inhibition zone. The dichloromethane extract exhibited a 9 mm inhibition zone against Acinetobacter baumannii, with a minimum inhibitory concentration (MIC) of 10 µL/mL for both extracts and all susceptible strains. Antioxidant activity, measured by radical DPPH∙ radical reduction test revealed significant reducing power in the ethanolic extract, with an IC50 = 1.383 ± 0.069 mg/mL, compared to IC50 = 0.095 ± 0.009 mg/mL for ascorbic acid, used as reference.