Structurally varied Cu(II) complexes involving kinetin and its derivatives: Synthesis, characterization and evaluation of SOD-mimic activity

Physiological and biochemical effects of nanoparticulate copper, bulk copper, copper chloride, and kinetin in kidney bean (Phaseolus vulgaris) plants

It is essential to understand the interactions of engineered nanoparticles (ENPs) with additives used in agriculture and their impacts on crop plants. In this study, kidney bean (Phaseolus vulgaris) plants were grown in potting soil amended with either nano copper (nCu), bulk copper (bCu), or copper chloride (CuCl₂) at 0, 50, and 100mg/kg, combined with 0, 10, or 100μM of kinetin (KN). Plant growth, Cu, micro and macroelement concentrations, chlorophyll content, and enzymatic activity were examined in 55-day old plants. Results showed that root Cu content was at least 10-fold higher, compared to other tissues. Accumulation of Cu in roots was decreased by 100μM KN up to 25%. A concentration-dependent increase of Cu content in leaves by Cu×KN was observed. Chlorophyll production was diminished by CuCl₂+KN between 22 and 30%, showing a hormetic response. Catalase activity was repressed by 65% to 82% in bCu and CuCl₂ treatments. From all essential elements, Ca, Mn, and P were reduced by 33% to 97% in bCu, CuCl₂, and CuCl₂+KN treatments. However, this did not impact stem elongation and tissue biomass that increased up to 55% under exposure to bCu and CuCl₂. Our results demonstrate that KN combined with ionic Cu could have negative implications in kidney bean plants, since this combination impacted chlorophyll production and nutrient element accumulation.

SOD-Mimic Cu(II) Dimeric Complexes Involving Kinetin and Its Derivative: Preparation and Characterization

Two SOD-mimic active dimeric Cu(II) chlorido complexes of the compositions [Cu(2)(μ-HL(1))(4)Cl(2)]Cl(2) (1) and [Cu(2)(μ-HL(2))(2)(μ-Cl)(2)(HL(2))(2)Cl(2)] · 4H(2)O (2) involving the cosmetologically relevant cytokinin kinetin (N6-furfuryladenine, HL(1)) and its derivative N6-(5-methylfurfuryl)adenine (HL(2)) have been synthesized and characterized by elemental analysis, infrared, and electronic spectroscopy, ESI+ mass spectrometry, conductivity and temperature dependence of magnetic susceptibility measurements, and thermogravimetric (TG) and differential thermal (DTA) analyses. The results of these methods, particularly the temperature dependence of magnetic susceptibility, showed the complexes to be dimeric with a strong antiferromagnetic exchange (J = -290 cm(-1) for complex 1 and J = -160 cm(-1) for 2). The complexes have been identified as auspicious SOD-mimics, as their antiradical activity evaluated by the in vitro SOD-mimic assay resulted in the IC(50) values equal to 8.13 μM (1) and 0.71 μM (2).