In the present investigation, culture A. niger was used for the biosynthesis of CuO-NPs using mango (Mangifera indica) leaves aqueous extract. This method of green synthesis is simple, more environment friendly and easy to scaled up. The obtained CuO-NPs were characterized using FT-IR, XRD, TEM, EDX and DLS to evaluate their structure, morphology, elemental composition, and particle size distribution. These findings verify the generation of spherical, crystalline CuO-NPs with an average size of 35.1 nm. The biosynthesized plant-based CuO-NPs showed potential antimicrobial and catalytic, with the higher concentration (till 6.0 mg/mL) having effect better the effect. When used for wastewater treatment, under solar light, the NPs exhibited superior decolorization with a performance of 80.1 ± 1.5% at 6.0 mg/mL after 250 min, which is better than the 61.3 ± 1.3% observed in the dark. Moreover, the physicochemical parameters, viz., (TSS), (TDS), (COD) and (BOD) were also decreased significantly by 90.93%, 82.59%, 91.2% and 82.65%, respectively in the best process condition. Also the concentrations of heavy metals (cobalt, Co; lead, Pb; nickel, Ni; cadmium, Cd; and hexavalent chromium, Cr (VI)) were significantly reduced up to 69.9%, 79.7%, 75.0%, 77.0%, and 91.2%, respectively. Antimicrobial analysis demonstrated the CuO-NPs at the minimum inhibitory concentrations (MICs) of 100, 25, 100, 100, 25, and 50 μg/mL against Bacillus subtilis, Enterococcus faecalis, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae, correspondingly. To sum up, mango leaf mediated synthesis of CuO-NPs acts as potent antibacterial agent as well as a catalyst for the wastewater treatment so as to their application in sustainable treatment of industrial effluent.
Talib et al. (Tue,) studied this question.