Phytochemical Profiling and In vitro Antioxidant and Antimicrobial Evaluation ofAzadirachta indica and Melia azedarach

Abstract

The present study investigated the phytochemical composition, antioxidant potential, and antibacterial activity of Azadirachta indica and Melia azedarach leaf methanolic extracts. Preliminary phytochemical screening detected steroids, alkaloids, phenols, flavonoids, saponins, tannins, anthraquinones, and amino acids in both extracts. Phytochemical fingerprinting was performed using high-performance liquid chromatography (HPLC) and thin-layer chromatography (TLC). HPLC analysis revealed seven major chromatographic peaks in M. azedarach and three in A. indica. TLC profiling identified eight phenolic and three steroidal bands in A. indica, while M. azedarach exhibited sixteen phenolic and three steroidal bands. Antioxidant activity was evaluated using DPPH, ABTS, CUPRAC, and FRAP assays, while total phenolic content was determined using the Folin–Ciocalteu method. Antibacterial activity was assessed against Escherichia coli, Bacillus cereus, Staphylococcus epidermidis, and Enterobacter aerogenes using disc- and well-diffusion methods. A. indica exhibited the highest activity against E. coli, with inhibition zones of 18 ± 0.18 and 21 ± 0.18 mm, respectively, and against E. aerogenes, with zones of 16 ± 0.11 and 18 ± 0.27 mm. MIC analysis further demonstrated concentration- and exposure-timedependent antibacterial effects. Overall, both extracts demonstrated diverse phytochemical profiles, antioxidant activity, and antibacterial potential, supporting their further investigation as natural sources of bioactive compounds.