Green Synthesis of Copper Nanoparticles from Pineapple Peel Dietary Fibers: Antibacterial, Antifungal, Antioxidant, and Antidiabetic Activities

Dietary fiber-based approaches have recently gained notable attention in biomedical applications due to their biocompatibility, biodegradability, and eco-friendliness. Ripe Ananas comosus (pineapple) peel, typically discarded as waste, is a rich source of soluble dietary fiber, cellulose, and hemicellulose. In the present study, a green method was employed for first-time synthesis of copper nanoparticles (Cu-Nano) using dietary fiber extract derived from A. comosus peel powder. UV-Visible analysis and ATR-FTIR spectroscopy confirmed the reduction of copper ions and successful synthesis of Cu-Nano. The nanoparticles exhibited hydrodynamic diameter of 253.6 nm, confirming their nanosized dimensions, and showed zeta potential of −17.34 mV, indicating good colloidal stability. Furthermore, HR-TEM analysis revealed uniformly dispersed spherical particles with average diameter of 6.57 ± 1.50 nm, while XRD analysis confirmed their crystalline nature. The Cu-Nano exhibited significant antibacterial activity against Staphylococcus aureus and Escherichia coli, as well as antifungal activity against Aspergillus niger and Fusarium moniliforme. Additionally, Cu-Nano demonstrated strong antioxidant activity (IC50: 88.27 ppm) and effective inhibition of α-amylase (IC50: 420.32 ppm), indicating promising antidiabetic potential. In conclusion, green-synthesized Cu-Nano utilizing dietary fibers from pineapple peel waste represents promising multifunctional therapeutic platform with potent antimicrobial, antioxidant, and antidiabetic effects, holding significant potential for future biomedical applications. First report on green-synthesis of copper-based dietary fiber nano-agents (Cu-Nano) using waste Ananas comosus peels.It exhibited enhanced antibacterial aptitude against both gram-positive and gram-negative bacterial strains.It displayed excellent antifungal activity against Aspergillus niger and Fusarium moniliforme.The stable, nanosized, and uniformly dispersed Cu-Nano showed significant antioxidant potential.The inhibition of α-amylase confirmed the antidiabetic potential of green-synthesized Cu-Nano. First report on green-synthesis of copper-based dietary fiber nano-agents (Cu-Nano) using waste Ananas comosus peels. It exhibited enhanced antibacterial aptitude against both gram-positive and gram-negative bacterial strains. It displayed excellent antifungal activity against Aspergillus niger and Fusarium moniliforme. The stable, nanosized, and uniformly dispersed Cu-Nano showed significant antioxidant potential. The inhibition of α-amylase confirmed the antidiabetic potential of green-synthesized Cu-Nano.