Antibacterial Potential and Time-Kill Kinetics of Calotropis procera Extracts

The escalating challenge of bacterial resistance to antibiotics has prompted interest in exploring the antibacterial potential of Calotropis procera. To investigate the antibacterial efficacy of C. procera, the leaves and stems of the plant were collected and macerated in ethanol to obtain crude extracts. Using GC-MS analysis, we identified key phytochemicals in the leaf and stem extracts of the plant. Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, and Staphylococcus aureus were selected for the study. We used the Kirby Bauer disc diffusion test to evaluate bacterial susceptibility to C. procera extracts, while the minimum inhibitory concentration (MIC) was determined using microdilution plates. Additionally, time-kill kinetics were assessed for each bacterium. The stem extract demonstrated superior activity, achieving complete bactericidal effects against Pseudomonas aeruginosa and Escherichia coli within 20 hours. Phytochemicals such as Lupenyl Acetate and Phytol were identified as key bioactive compounds. These findings highlight the potential of C. procera as a natural source for developing antimicrobial agents. Statistical analysis strongly suggests that C. procera extracts significantly affect the test bacteria (p = 0.001). In conclusion, the leaf and stem extracts of C. procera exhibit distinct variations in the relative abundance of bioactive compounds and further demonstrate multiple antimicrobial mechanisms. These properties of the plant highlight its potential as a valuable resource in addressing antibiotic-resistant bacterial strains.