Harnessing green chemistry for waste water remediation through Alpinia leaves silver nanoparticles

Addressing environmental concerns with sustainable nanomaterial is a vital step towards innovative and eco-friendly techniques that address important global issues like pollution, water contamination, and resource depletion. This eco-friendly approach offers a sustainable alternative to conventional methods and this study aims to showcase the applications of biogenic silver nanoparticles (AgNPs) synthesized using green synthesis techniques with aqueous leaf extracts from five Alpinia varieties; Alpinia purpurata, Alpinia caerulea, Alpinia zerumbet ‘variegata’, Alpinia calcurata and Alpinia zerumbet. The AgNPs were synthesized using water extracts (WE) and silver nitrate at the optimum conditions. Characterization of AgNPs using UV-Vis spectroscopy and scanning electron microscopy (SEM), confirmed their successful formation and morphology. Spherical A.zerumbet_AgNPs between 28–68 nm in size were observed. The photocatalytic activity was tested by degrading methyl Orange (MO) dye under solar irradiation and the use NaBH₄ with AgNPs significantly increased the degradation of MO. P-nitrophenol catalysis using AgNP and NaBH₄resulted promising results. Cytotoxicity of AgNPs using Artemia salina was evaluated and 100% viability was seen. The antibacterial activity was conducted using Escherichia coli and Staphylococcus aureus, unlike the WEs, all AgNPs showed antibacterial activity. This study revealed that the AgNPs synthesized using Alpinia leaves has diverse functional properties, presenting a promising avenue for future research and practical applications in environmental pollution.