Potential of <em>Portulaca oleracea</em> Extract as a Green Reducing Agent for Silver Nanoparticle Synthesis to Enhance the Antibacterial Activity of Microcellulose Derived from Coconut Water

This study investigates the structural and antimicrobial properties of coconut water–derived microcellulose biocomposites incorporated with glycerol, chitosan, and silver nanoparticles. Microcellulose-based films were fabricated as silver nanoparticle–deposited microcellulose (MN), microcellulose–glycerol–silver nanoparticles (MG), microcellulose–chitosan–silver nanoparticles (MChN), and microcellulose–glycerol–chitosan–silver nanoparticles (MGChN). Antimicrobial performance was evaluated against Pseudomonas aeruginosa, Staphylococcus epidermidis, and Candida albicans using inhibition zone assays. The MG and MGChN films exhibited enhanced elasticity compared to MN and MChN, indicating the plasticizing effect of glycerol. Enzymatic hydrolysis using xylanase yielded microcellulose particles with sizes ranging from 1.19 to 2.07 μm and induced a bio-bleaching effect. Among all formulations, MGChN demonstrated the highest antimicrobial activity against P. aeruginosa and S. epidermidis (strong category), as well as moderate antifungal activity against C. albicans. Overall, the synergistic incorporation of glycerol, chitosan, and silver nanoparticles significantly improved the antimicrobial efficacy of coconut water–based microcellulose, underscoring its potential for advanced biomedical polymer applications.