The comparative studies on the interaction of baicalein and baicalin with bovine serum albumin and the influence of glucose
- VernacularTitle:黄芩素及黄芩苷与牛血清白蛋白结合作用比较研究及葡萄糖的影响
- Author:
Yun HUANG
;
Lijian CUI
;
Chen CHEN
;
Yuhong DOU
;
Wenhong ZHAN
;
Yongli WANG
- Publication Type:Journal Article
- Keywords:
baicalein;
baicalin;
bovine serum albumin;
fluorescence quenching;
thermodynamic parameters;
glucose
- From:
Chinese Pharmacological Bulletin
1986;0(06):-
- CountryChina
- Language:Chinese
-
Abstract:
Aim To compare the interactions of baicalein and baicalin with bovine serum albumin (BSA) and their mechanism. Methods The binding reactions of baicalein and baicalin with BSA and the effects of glucose on them were studied by spectroscopy to compare the binding constants and binding distances of baicalein-BSA and baicalin-BSA,which were calculated according to Lineweaver-Burk equation and F?ster' energy transfer theory. Thermodynamic parameters were used to calculate the types of interaction force between BSA with baicalein or baicalin and the technique of synchronous fluorescence spectra was used to observe the effects of baicalein or baicalin on the conformation of BSA. Results Both the binding constants and binding distances of baicalein-BSA and baicalin-BSA decreased with temperature increasing and were increased by glucose. Relative to baicalein,the binding affinity of baicalin to BSA decreased obviously with an increase in binding distance. Both baicalein and baicalin could form non-covalent compounds with BSA mainly to quench the intrinsic fluorescence of BSA through a static quenching procedure. Baicalein could interact with BSA through hydrogen bonds and Van der Waals force,and baicalin did it mainly through electrostatic force. Though baicalein or baicalin could induce the conformational changes of BSA by binding reaction,only the former reduced the hydrophobicity in microenvironment around the tryptophan moieties of BSA. Conclusions The glycosylation substitution of baicalein molecule can decrease the binding to BSA (baicalin-BSA) and change the types of interaction force. The physiological concentration of glucose increases the binding constants and the number of binding sites of baicalein and baicalin with BSA.
