Evaluation of Medicinal Properties of Azadirachta indica Extracts and Their Biosynthesized Silver Nanoparticles

Abstract

Purpose: Harnessing the therapeutic wealth of medicinal plants through nanotechnology has emerged as a powerful frontier in drug discovery. This study explores the medicinal properties of Azadirachta indica (Neem) leaf extracts and their biosynthesized silver nanoparticles, bridging traditional knowledge with modern biomedical innovation. Methods: Aqueous and ethanolic leaf extracts of A. indica were prepared and analyzed for proximate composition, mineral content, and key phytochemicals using standard procedures. Antioxidant activity was assessed by DPPH, nitric oxide, FRAP, and TBARS assays. Silver nanoparticles were synthesized using the aqueous extract and monitored by UV–Visible and Fourier-transform infrared (FTIR) spectroscopy. Antibacterial activity of the extracts and biosynthesized AgNPs was evaluated using the disk diffusion method. Results: Proximate analysis indicated that A. indica leaves are nutritionally dense, with high protein (25.35%) and carbohydrate (33.32%) content, and moderate levels of crude fat (10.20%) and fiber (9.74%). Mineral profiling revealed appreciable amounts of essential elements such as magnesium, calcium, potassium, iron, and zinc. Phytochemical evaluation showed that the extracts contained flavonoids, steroids, saponins, and phenolic constituents. Antioxidant screening demonstrated efficient scavenging of DPPH and nitric oxide radicals, along with notable ferric reducing antioxidant power. The aqueous extract displayed measurable antibacterial activity, whereas the biosynthesized silver nanoparticles produced markedly stronger antibacterial effects. FTIR analysis confirmed the involvement of hydroxyl, carbonyl, and amine functional groups in AgNP formation. Conclusion: These findings show that A. indica possesses rich bioactive constituents and effectively mediates AgNP synthesis, producing nanoparticles with enhanced antibacterial activity.