Exploration of potent antimicrobial and antioxidant bioactive compounds of selected medicinal plants against drug-resistant pathogens.

Abstract

Antibiotic resistance is an escalating universal health threat in this modern era, driving the need for innovative therapeutic solutions. Medicinal plants extensively utilized in Ayurveda, offer significant promises as antibacterial agents. This study examines the metabolite composition of methanol crude extracts from Datura metel and Phyllanthus amarus and evaluates their antibacterial and antioxidant properties. The metabolite content of the crude extracts from the leaves of selected plants was investigated and characterized using HPLC and GC-MS techniques. The agar well diffusion method was used to evaluate antibacterial activity against eight pathogenic bacterial strains, and antioxidant activity was measured using the DPPH assay. Among the tested crude extracts, Datura metel exhibited the strongest antibacterial activity against Salmonella typhi, Acinetobacter baumannii, Klebsiella pneumoniae, and methicillin-resistant Staphylococcus aureus (MRSA). Phyllanthus amarus showed notable activity against Salmonella typhi, Acinetobacter baumannii, methicillin-susceptible Staphylococcus aureus (MSSA), and Klebsiella pneumoniae. The extracts exhibited antimicrobial activity against the tested organisms, with the average diameter of the zone of inhibition ranging from 19 to 21 mm and the two leaf extracts exhibited varying degrees of antibacterial activity. In antioxidant assays, the Datura metel extract demonstrated superior activity, with 78.3 ± 2% inhibition and an IC50 value of 40.1 ± 4 µg/mL. These findings highlight Datura metel and Phyllanthus amarus as promising sources of natural antibacterial and antioxidants, offering potential applications in managing infectious diseases.

Supplementary information: The online version contains supplementary material available at 10.1007/s13205-025-04228-2.