Green fabrication of copper oxide nanoparticles via Cinnamomum zeylanicum Blume bark and its role in antimicrobial, antioxidant, antidiabetic, and photocatalytic applications
摘要
The present study proposes a cost-effective and ecofriendly technique for the green fabrication of CuO-NPs using the ethanol extract of C. zeylanicum Blume bark (family Laureaceae), commonly known as Dalchini. C. zeylanicum bark extract was used as a biological reduction agent for synthesizing CuO-NPs by optimizing the synthesis conditions to achieve a narrow size range of nanoparticles. Our primary objective was to comprehensively characterize the ethanol extract of C. zeylanicum bark and CuO-NPs and assess their antioxidant, antidiabetic, and antimicrobial efficacies. The structural and compositional properties were analyzed using UV-Vis, FTIR, XRD, FESEM-EDX, HRTEM, DLS, zeta potential, and Raman spectroscopy. UV-visible spectroscopy revealed a distinct absorption peak at 350 nm. FTIR confirmed the presence of various functional groups and physical interactions of macromolecules with CuO-NPs. The peaks observed at 561.31 and 700.19 cm-1 indicate the formation of CuO nanostructures and the CuO stretching mode. XRD revealed the monoclinic crystalline morphology of the CuO-NPs with an average crystal size of 30 nm. DLS showed the presence of nanoparticle agglomeration, and the zeta potential was − 27.11 mV. FESEM and HRTEM micrographs confirmed the spherical shape of CuO-NPs and revealed nanoparticle dimensions of approximately 20–30 nm, respectively. The percentages of Cu, O, and C present in the CuO-NPs were 25.65, 23.87, and 39.73%, respectively, as determined by EDX. The green-synthesized CuO-NPs exhibited significant multifaceted bioactivity and catalytic efficiency. The CuO-NPs exhibited high antimicrobial activity against Escherichia coli, Enterococcus faecalis, and Candida albicans, and potent radical scavenging activity against DPPH, achieving an IC50 value of 10.89 ± 0.03 µg/mL. Antidiabetic potential using an α-glucosidase inhibition assay, where 65.55% inhibition was achieved at a concentration of 20 µg/mL with an IC50 value of 5.48 µg/mL. Furthermore, the CuO-NPs acted as effective photocatalysts, successfully degrading 83.75% of Methylene Blue (MB) dye within 120 min. of exposure. These results suggest that C. zeylanicum-mediated CuO-NPs are a viable and sustainable alternative for developing next-generation agents to combat microbial infections, diabetes, oxidative stress, and environmental pollutants.