Title
Anti-aggregation property of thymoquinone induce by copper-nanoperticles: A biophysical approach
Author
Mohd Ishtikhar, Rahisuddin, Mohsin Vahid Khan, Rizwan Hasan Khan
Year
2016
Journal
International Journal of Biological Macromolecules
Abstract
Quaternary amine of diethylaminoethyl rosin ester (QRMAE), chemically synthesized by rosin modified biocompatible cationic surfactant, has various biological applications in the field of pharmacy as well as used as food product additive. Here, we report biophysical insights in to the interaction mechanism of thymoquinone (TQ), copper nanoparticles (Cu-NPs) and QRMAE with bovine serum albumin (BSA) individually and also in complexes forms to determine their competitive binding affinity. We have also studied the aggregation–inhibition effects of Cu-NPs and TQ individually, as well as in complexes form in the presence of QRMAE surfactants which is responsible for induction of amorphous aggregates in BSA within hours of incubation at 65 °C and physiological pH. The formation of aggregates was established by using various spectroscopic methods and dye binding assay. The circular dichroism (CD) spectroscopy showed that QRMAE significantly altered the secondary structure of BSA. However, the presence of TQ and Cu-NPs restricted the aggregation process which was observed to be more efficient when TQ and Cu-NPs were present together. This study provides very significant competitive binding results of QRMAE, Cu-NPs, TQ and protein aggregation behavior at higher temperature which was induced by rosin surfactant QRMAE, and this aggregation process was inhibited by Cu-NPs, TQ individually and together. Therefore, our finding suggested that rosin surfactant QRMAE has high propensity to induce amorphous aggregation in BSA which was favored at elevated temperature and higher concentration of the protein. When BSA-QRMAE sample was incubated in the presence Cu-NPs under similar condition, the aggregation propensity reduced, and drastically inhibited by TQ and Cu-NPs together.
Instrument
J-815
Keywords
Circular dichroism, Secondary structure, Thermal stability, Nanostructures, Aggregation, Ligand binding, Biochemistry, Materials