Interações Competitivas De Complexos De Rutênio Contendo Dimetilsulfóxido E Ligantes N-Heterocíclicos Com Albumina De Soro Humano

Abstract

COMPETITIVE INTERACTIONS OF RUTHENIUM COMPLEXES CONTAINING DIMETHYLSULFOXIDE AND N-HETEROCYCLIC LIGANDS WITH HUMAN SERUM ALBUMIN. Two ruthenium complexes of the type [RuCl(dmso)(L) 2 ] Cl {L = 4,4'-dimethyl-2,2'-bipyridine (dmbpy); 4,4'-dinonyl-2,2'-bipyridine (dnbpy)} have been synthesized and characterized by elemental analysis, 1 H NMR, FTIR, electronic spectra, and molar conductivity. The IR spectral studies revealed that the DMSO molecule is S-bound (ν SO = 1100 cm-1 ; 1079 cm-1). For complexes, MLCT bands were observed around 390 nm and 440 nm. The measurements of conductivity revealed the presence of 1:1 electrolyte. Interactions of ruthenium complexes with human serum albumin were examined by fluorescence spectroscopy. The results revealed a combined quenching mechanism of HSA fluorescence by [RuCl(dmso)(dmbpy) 2 ]Cl, with binding constant of 5.82 ± 0.08 x 10 5 mol-1 L (297 K), 5.29 ± 0.06 x 10 5 mol-1 L (303 K), and 4.68 ± 0.06 x 10 5 mol-1 L (313 K), whereas the [RuCl(dmso)(dnbpy) 2 ]Cl caused static quenching predominantly, with binding constant of 9.87 ± 0.05 x 10 5 mol-1 L (297 K), 3.41 ± 0.04 x 10 5 mol-1 L (303 K), and 0.89 ± 0.05 x 10 5 mol-1 L (313 K). The binding process occurred spontaneously and was mainly driven by enthalpy, as evidenced by thermodynamic parameters. Site marker competitive experiment showed that ruthenium complexes bind to the warfarin binding site in subdomain IIA of HSA.

Minimizing Ochratoxin A Contamination through the Use of Actinobacteria and Their Active Molecules

“…Another assumption could be that secondary metabolites are produced in higher quantity when the bacteria is in contact with the fungi. Many recent studies have highlighted that the co-culture of microorganisms can lead to an overproduction of secondary metabolites [45][46][47][48]. Thus, the secretion of OTA or other secondary metabolites by the fungi could enhance the secretion of antifungal compounds or antitoxinogenic compounds by actinobacteria.…”