Radical Scavenging Capability Influences the Multifarious Therapeutic Tendencies of Phyto-Engineered CuO Nanostructures

In this study, physicochemical and functional characterization of phyto-mediated copper oxide nanoparticles (CuO NPs) using three plants viz. Alternanthera pungens (Ap), Adiantum incisum (Ai) and Trichodesma indicum (Ti) were carried out in comparison with the vehicle control (Cu-V) produced under similar experimental conditions. CuO NPs revealed UV–Vis spectra in the range of 350–450 nm with distinct effect of different plants on their morphological and chemical characteristics as analyzed via SEM and FTIR. However, nanoparticle sizes (15–17 nm) as deduced via XRD were not influenced by the plants selected. Utilizing the biosynthesized CuO NPs, microbicidal assessment against selected bacterial and fungal strains revealed profound results against several microorganisms, with predominant action by Cu-Ap against Aspergillus fumigatus (MIC: 9.21 ± 0.5 µg/ml). Additionally, Cu-Ap but not Cu-V disclosed outstanding performance revealing noticeable inhibitory concentrations IC50 for antioxidant (49.66 ± 3.7 µg/ml), antidiabetic (22.74 ± 4.2 µg/ml), anti-inflammatory (100.82 ± 3.3 µg/ml), antitumor (20.61 ± 2.5 µg/ml) and MTT cytotoxicity (3.98 ± 0.8 µg/ml against HeLa cells) assessments. The use of Annexin V-FITC indicated that all types of CuO NPs prompted early apoptosis among HeLa cells. Pearson’s correlation suggested fairly strong positive relationship (r ~ 0.5–1) between antioxidant activities of tested nanoparticles with identified biological efficacies. Insignificant therapeutic potency of Cu-V established the profound impact of medicinal plants’ phytoconstituents upon augmented pharmacological capacities of biogenic CuO NPs.