DOI: https://doi.org/10.55373/mjchem.v26i2.96

Keywords: Green synthesis; ·Blumea lacera; Leaf extract; Silver nanoparticles; Antibacterial; Antifungal

Abstract

Green synthesis of silver nanoparticles (AgNPs) has been proven as an alternative method owing to its environmentally benign nature. This study used an eco-friendly method utilising Blumea lacera leaf extracts to prepare AgNPs which were then characterized by UV-Vis, FTIR, XRD, SEM, EDX, SAED and TEM, and evaluated for their antimicrobial activity. The formation of Bl-AgNPs was primarily confirmed by the UV-Vis absorption maximum at 454 nm, while FTIR spectra confirmed the presence of biomolecules, e.g., ketones, ethers, esters, flavonoids, polyphenols or alkaloids that facilitated the green synthesis of AgNPs. SEM and TEM analyses determined that AgNPs had a spherical shape, with an average size of 19 ± 7 nm. Antibacterial tests were performed using disc diffusion and macro-broth dilution assays against both gram-positive (Bacillus cereus and Staphylococcus aureus) and gram-negative (Escherichia coli, Salmonella typhi, Pseudomonas sp.) bacterial strains, in which Bl-AgNPs showed substantial antibacterial activity. Antifungal tests conducted on Aspergillus nigar and Candida albicans fungal strains showed that their growths were inhibited by up to 72.97 % and 78.19 %, respectively, at a concentration of 650 μg/mL. Bl-AgNPs exhibited good antimicrobial action in a dose-dependent manner. The present study demonstrates that Bl leaf extracts may be employed to fabricate stable AgNPs for use in biomedical materials.