Studies of the Interaction Between Hesperidin and Its Aglycone Hesperetin with Bovine Serum Albumin by Spectroscopic Methods

The interaction between hesperidin and its aglycone hesperetin with bovine serum albumin in physiological buffer (pH = 7.4) is investigated by spectroscopic methods. The results reveal that both hesperetin and hesperidin could strongly quench the intrinsic fluorescence of bovine serum albumin. The quenching mechanism of hesperetin for bovine serum albumin is a static quenching procedure, but hesperidin for bovine serum albumin is a dynamic quenching. The apparent binding constants (Ka) and number of binding sites 'n' of hesperetin and hesperidin with bovine serum albumin are obtained by fluorescence quenching method. The interaction of hesperetin with bovine serum albumin is driven mainly by hydrogen bonding and van't Hoff and hesperidin with bovine serum albumin is driven mainly by hydrophobic. The distance 'r' between bovine serum albumin and hesperetin is calculated to be 3.08 nm. The results of synchronous fluorescence spectra show that binding of hesperidin and hesperetin with bovine serum albumin can't induce conformational changes in bovine serum albumin.