Biogenic Copper Oxide Nanoparticles from Chamaecostus cuspidatus Leaves: Dual Action Against Hyperglycemia and Oxidative Stress

Chamaecostus cuspidatus, naturally referred as the “insulin plant,” is renowned for its potent antidiabetic properties. This study explores the sustainable synthesis of CuO NPs using a methanolic extract from C. cuspidatus leaves. A reactive hydrogen atom in plant flavonoids reduces Cu²⁺ to form copper nuclei in the nucleation of CuO NPs. The manufactured CuO NPs were analysed using multiple analytical approaches. UV–visible spectroscopy confirmed their formation with a peak at 491 nm, while FTIR identified functional groups aiding stabilization. XRD confirmed their crystalline nature, SEM revealed morphological variations, and EDAX verified the presence of copper and oxygen. The antioxidant efficacy of CuO NPs evaluated through DPPH and ABTS assays, showing significant free radical scavenging. Additionally, α-amylase and α-glucosidase inhibition assays demonstrated notable antidiabetic activity, with inhibition rates of 53.25% and 46.29%, respectively. These results emphasize the potential of C. cuspidatus as a natural, green source for copper oxide nanoparticles with propitious antioxidant and antidiabetic properties.