chrysin/β-cyclodextrin supramolecular system: a quantum mechanical investigation

Chrysin is a bioflavonoid which possesses a wide range of important biological activities. in present study, we used a quantum mechanical approach to shed light on the antioxidant ability and antioxidant mechanism of chrysin to scavenge hydroxyl radical (˙oh) in solution phase. the analysis of the theoretical bond dissociation enthalpy (bde) values and spin density of the radicals to determine the delocalization possibilities at b3lyp/6-311++g** level clearly shows the importance of the a-ring and the 7-oh group in antioxidant reactivity. in the next step, the inclusion of chrysin with β-cd has been investigated extensively using theoretical methods. density functional theory (m05-2x) employing the 6–31+g* basis set has been used to research the lowest energy geometry for all studied complexes in gas and water mediums. the results of calculations show that the a ring of chrysin with large cavity side of β-cd significantly formed the favorable β-cd/chrysin complex in both phases. our observations also inferred that hydrogen bonds were the key interactions which stabilized the chrysin/β-cd complex. we used bader’s atoms in molecules (aim) theory to perform a topological study on chrysin/β-cd complex to emphasize the hydrogen bonds. according to our findings, the process of inclusion increased not only the solubility of chrysin but also its antioxidant potential.