title: Binding of the bioactive component jatrorrhizine to human serum albumin.
abstract: The interaction between Jatrorrhizine with human serum albumin (HSA) were studied by fluorescence quenching technique, circular dichroism (CD) spectroscopy, and Fourier transform infrared (FT-IR) spectroscopy. Fluorescence data revealed the presence of a single class of binding site on HSA and its binding constants (K) are 7.278 x 10(4), 6.526 x 10(4), and 5.965 x 10(4) L.mol(-1) at 296, 303, and 310 K, respectively. The CD spectra and FT-IR spectra have proved that the protein secondary structure changed in the presence of Jatrorrhizine in aqueous solution. The effect of common ions on the binding constants was also investigated. In addition, the thermodynamic functions standard enthalpy (DeltaH(0)) and standard entropy (DeltaS(0)) for the reaction were calculated to be -10.891 kJ.mol(-1) and 56.267 J.mol(-1) K(-1), according to the van't Hoff equation. These data indicated that hydrophobic and electrostatic interactions played a major role in the binding of Jatrorrhizine to HSA. Furthermore, the displacement experiments indicated that Jatrorrhizine could bind to the site I of HSA, which was also in agreement with the result of the molecular modeling study.
authors.affiliation: Department of Chemistry, Lanzhou University, Lanzhou 730000, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Li
authors.forename: Wenying
authors.initials: W
authors.lastname: He
authors.forename: Jiaqin
authors.initials: J
authors.lastname: Liu
authors.forename: Fenling
authors.initials: F
authors.lastname: Sheng
authors.forename: Zhide
authors.initials: Z
authors.lastname: Hu
authors.forename: Xingguo
authors.initials: X
authors.lastname: Chen
mesh_terms: D001599:Berberine / Q000031:analogs & derivatives* / Q000378:metabolism*; D001665:Binding Sites; D002942:Circular Dichroism; D006801:Humans; D007477:Ions / Q000737:chemistry; D008958:Models, Molecular; D015394:Molecular Structure; D010936:Plant Extracts / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D017433:Protein Structure, Secondary; D012709:Serum Albumin / Q000737:chemistry / Q000378:metabolism*
chemical_list: D007477:Ions; D010936:Plant Extracts; D012709:Serum Albumin; C055785:jatrorrhizine; D001599:Berberine