In vitro antioxidant and antibacterial activities of biogenic synthesized zinc oxide nanoparticles using leaf extract of Mallotus philippinensis Mull. Arg

= 66.87 µg/ml). Furthermore, the ZnO NPs demonstrated significant antibacterial activity against both gram-positive and gram-negative bacteria, including Klebsiella pneumoniae (K. pneumoniae), Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), and Streptococcus pneumoniae (S. pneumoniae). The highest antibacterial activity was observed against S. pneumoniae, with a zone of inhibition of 14.97 ± 0.38 mm for ZnO NPs synthesized using zinc nitrate. These findings suggest that M. philippinensis leaf extract is an effective reducing and capping agent for the biosynthesis of ZnO NPs. The resulting nanoparticles exhibit potent antioxidant and antibacterial properties, highlighting their potential applications in biomedical and environmental fields.