DNA binding, cytotoxic effects and probable targets of an oxindolimine–vanadyl complex as an antitumor agent

The vanadyl–oxindolimine complex as an antitumor agent.

α-AMYLASE INHIBITION AND ELECTROCHEMICAL BEHAVIOR OF SOME OXOVANADIUM (IV) COMPLEXES OF L-AMINO ACIDS

Objective: Diabetes is complex metabolic disease having a symptom of hyperglycemia. Oxovanadium (IV) and l-amino acids are used to normalize the hyperglycemic condition. The aim of this study was to screen the α-amylase inhibitory activity of l-amino acids, their oxovanadium (IV) complexes, and electrochemical activity of oxovanadium (IV) complexes.Methods: All the oxovanadium (IV) complexes were synthesized according to the solubility of l-amino acids; the molar ratio of metal to l-amino acid was 1:2. The synthesized oxovanadium (IV) complexes were examined for their electrochemical behavior in 0.01 M sodium perchlorate solution. Further, the oxovanadium (IV) complexes of l-amino acids and l-amino acids were screened for their α-amylase inhibitory activity using spectrophotometric assay system.Results: The synthesized complexes were divided into four groups according to nature of amino acids. Entire complexes show simple irreversible wave for VO redox couples in −900–50 mV potential range and scan rate was 300 mV/S. All the complexes and l-amino acids were screened for their α-amylase inhibitory activity. L-Histidine and their oxovanadium (IV) complex show the minimum IC50 value, i.e. 4199.05 μM and 101.015 μM, respectively, in their respective groups.Conclusion: The data obtained from our study, it reveals that the entire oxovanadium (IV) complexes are an irreversible wave for VO redox system and the l-histidine and its oxovanadium (IV) complex is the most potent inhibitor for the α-amylase. Further, the complexes show minimum IC50 value on comparing their respective ligands due to the interaction of Vanadyl complex to the enzyme, at the sixth vacant position of Vanadyl complex.

Textural and morphology changes of mesoporous SBA-15 silica due to introduction of guest phase

The research focuses on study of guest phase effect on the surface area and pore volume of SBA-15 with the emphasis on elucidation of reasons for these changes. The changes of surface area and pore volume are evident from evaluated N2 adsorption isotherms of VOx-SBA-15 even for samples with relative low content of supported guest phase, which is “atomically” spread on the surface in the form of anchored monomeric vanadyl species. These species cannot block the pore with diameter of 10 nm, nevertheless the presence of such phase causes decrease in adsorbed nitrogen during physisorption. Comparison of guest phase amount with differences in adsorbed amount of nitrogen led to conclusion that each vanadyl complex prevents adsorption of about one or two N2 molecules in the layer and influences two adsorption layers. Significant pore blocking occurs in the VOx-SBA-15 materials only in the case of presence bulk oxide-like nanospecies. Re-structuralization of silica mimicking phase separation phenomena relying on spinodal decomposition of a system was observed by SEM/TEM analysis and adsorption isotherms inspection for materials with high vanadium content.