Screening the bioactive compounds in aqueous extract of Coptidis rhizoma which specifically bind to rabbit lung tissues beta2-adrenoceptor using an affinity chromatographic selection method.
A receptor affinity chromatographic selection method was developed for screening the bioactive compounds binding to beta(2)-adrenoceptor (beta(2)-AR) in Coptidis rhizome. The bioactive compounds were analyzed by molecular recognition with a beta(2)-AR affinity column. The retention compounds eluted from the beta(2)-AR column were separated online with reverse-phase high-performance liquid chromatography by column switching technology, and identified by a coupled ion-trap mass spectrometer. Four compounds were screened as the bioactive compounds of Coptidis rhizome and identified as 2,9,10-trimethoxy-3-hydroxyl-protoberberine (jateorhizine), 2,3-methylenedioxy-9-methoxy-protoberberine, 2,3,9,10-tetramethoxy-protoberberine (palmatine) and 2,3-methylenedioxy-9,10-dimethoxy-protoberberine (berberine). The association constants of jatrorrhizine, palmatine and berberine to the beta(2)-AR were determined by the zonal elution method with standards. Berberine and palmatine had only one type of binding site on the immobilized beta(2)-AR. Their association constants were (2.28+/-0.11)x10(4)/M and (3.00+/-0.10)x10(4)/M, respectively. Jatrorrhizine had at least two type of binding sites on the immobilized beta(2)-AR, and the corresponding association constants were (2.20+/-0.09)x10(-4)/M and (6.78+/-0.001)x10(5)/M.
Zhao
Xinfeng
X
Key Laboratory of Resource Biology and Biotechnology in Western China, Ministry of Education, College of Life Sciences, Northwest University, Xi'an 710069, China.
Nan
Yefei
Y
Xiao
Chaoni
C
Zheng
Jianbin
J
Zheng
Xiaohui
X
Wei
Yinmao
Y
Zhang
Youyi
Y
D000818:Animals; D002846:Chromatography, Affinity / Q000379:methods*; D000089042:Coptis chinensis; D004365:Drugs, Chinese Herbal / Q000737:chemistry* / Q000378:metabolism; D008168:Lung / Q000737:chemistry* / Q000378:metabolism; D011485:Protein Binding; D011817:Rabbits; D018343:Receptors, Adrenergic, beta-2 / Q000737:chemistry* / Q000378:metabolism
D004365:Drugs, Chinese Herbal; D018343:Receptors, Adrenergic, beta-2; C107393:Coptidis rhizoma extract