[关键词]
[摘要]
目的 探究超声对超临界提取的强化作用。方法 在超临界提取厚朴稳定的工艺参数下,以提取物中厚朴酚与和厚朴酚的量和提取率为指标,比较了超声强化超临界提取、超声提取、超临界提取的效果。结果 超声强化超临界的提取效果明显优于两者的单独提取。结论 超声可强化超临界对厚朴有效成分的提取。
[Key word]
[Abstract]
Objective To study the interaction of quercitrin with human serum albumin (HSA) and the influence of glucose. Methods To investigate the interaction mechanism between quercitrin and HSA by spectroscopic method; to calculate the binding constants, binding sites, and binding distance according to double logarithmic plot and F?ster’s energy transfer theory, respectively; to explain the type of interaction force between quercitrin with HSA by thermodynamic parameters; to discuss the conformation change of HSA via synchronous fluorescence spectra. Results The fluorescence quenching mechanism of quercitrin to HSA was static quenching; The binding constants and the number of binding sites decreased with the increasing of temperature and glucose; The distance between the donor and acceptor was less than 7 nm; The hydrophobic forces played a major role in stabilizing quercetrin and HSA complex; The binding reaction had changed the micro-environmention of tryptophan residues. Conclusion Quercetrin could bind with HSA and change the conformation of HSA; The physiological concentration of glucose increases the binding constants and the number of binding sites of quercetrin with HSA.
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[基金项目]
国家自然科学基金资助项目(20872083);中国中医科学院中药研究所自然基金资助项目(ZZ20090107);山东省科技攻关项目(2010GSF10287);济南市高等院所自主创新计划项目(201004010)