The effect of quercetin flavonoid (

The effect of quercetin flavonoid (QUE), on the binding interaction of antihypertensive drug, amiloride (AMI) with bovine serum albumin (BSA) was investigated in this work. Spectroscopic methods such as steady state, synchronous, threeヾimensional fluorescence and circular dichroism spectroscopy were employed to study the interaction. Fluorescence data were analyzed using the Stern￢olmer equation and a static quenching process was found to be involved in the formation of AMI〣SA and QUE–BSA complexes which were in good agreement with the thermodynamic study. The thermodynamic parameters illustrated that the process is spontaneous and enthalpy driven. Hydrophobicity is acting as the primary force in the binding interaction. Fluorescence spectral data were resolved using multivariate curve resolution゛lternating least squares method (MCR〢LS). Site marker and molecular docking study confirmed the binding site of AMI on BSA, i.e . site II. The binding distance between amino acid of BSA and AMI was calculated and found to be 2.18 nm which indicated that energy transfer has occurred from amino acid of BSA to AMI. The binding affinity of AMI to BSA was found to be reduced in presence of QUE, which may lead to the poor distribution of AMI at the desired site.收