Green synthesis, characterizations, and in vitro biological evaluation of Cu (II) complexes of quercetin with N ^ N ligands

The primary goal of this research was to focus on the synthesis of two complex compounds, i.e., [{Cu (Q) (2, 2ʹbipyridalBpy) (acetate)} complex 1] and [{Cu (Q) (1, 10-phenanthrolinePhen) (acetate)} complex 2], which were found soluble in dimethyl sulfoxide and dimethylformamide. Complex 1 and 2 were incorporated and secluded as sole items in significant returns (>97%) by granulating strong fixing, i.e., quercetin (Q), copper acetate supported with Bpy, and Phen without any solvent. Both the synthesized compounds were characterized spectroscopically (Fourier transformation infrared spectroscopy, ultraviolet– visible, high-resolution mass spectroscopy, and elemental analysis) and biological (antioxidant, antibacterial, cytotoxicity, enzymatic, and nonenzymatic assay) evaluation was carried out against microbes. IC50 of synthesized complex 1 and 2 was determined as 168.97 and 125.932 μg/ml, respectively, whereas Q was found to be 38.1427 μg/ml. Minimum inhibitory concentration of both complexes (1,2) was determined as 25.83, 50.37, and 6.35, 13.74 μg/ml, respectively, in both strains (Escherichia coli and Staphylococcus aureus). Cell proliferation activity was carried out by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay method in both microbes and MG-63 cells. Treated organisms were researched for enzymatic (superoxide dismutase and catalase) and nonenzymatic (glutathione) assays, alongside lipid peroxidation and protein leakage tests. MTT assay was carried out in both microbes and MG-63 cells (toxicity was found to be safe up to 500 ppm compared to Q).