Synergistic effects of neem (Azadirachta Indica L.) Methanolic leaves extract with clindamycin against some microbes

Abstract

The rapid emergence of antimicrobial resistance has become a major global health concern, reducing the efficacy of conventional antibiotics. Plant-based bioactive compounds have gained increasing attention as potential alternatives or adjuvants to enhance antibiotic activity. The present study investigates the synergistic effect of methanolic leaf extract of Azadirachta Indica (Neem) in combination with clindamycin against selected microorganisms. The phytochemical results Indicated positive reactions for carbohydrates (Molisch test), phenolic compounds (Ferric chloride test), saponins (Foam test), flavonoids (Alkaline reagent test), and cardiac glycosides (Keller-Killiani test). The Biuret test for proteins showed negative results, while lipids were weakly positive. Synergistic effects of neem with clindamycin extract has shown better antimicrobial activity with yeast and lactobacillus compared to individual samples. Compounds from neem showed better docking results. Molecular docking analysis is showing the better binding conformation of Nimbin within the active site of killer toxin from halotolerant yeast (1KVE)) and Azadirachtin within the active site of Lactobacillus acidophilus glyceraldehyde-3-phosphate dehydrogenase (5J9G). The synergistic antibiotic compound with neem also shows better results compared to single antibiotic.