基于生物热力学表达的大青叶活性部分初筛

Establishment of a novel preliminary screening model for bioactive parts of folium of Isatis indigotica based on biothermodynamics

目的:从生物热力学角度出发,构建筛选中药活性部分的方法并探讨其可行性。方法:采用生物物理化学中较先进的微量量热方法,测定大青叶水煎液及其不同化学萃取部分对大肠杆菌的代谢影响,通过大青叶对大肠杆菌的热活性谱图(即热功率-时间曲线,P-t图)分析,得到一系列生物热力学参数。结合中医药理论分析了大青叶水煎液及其化学萃取部分的药效作用及差异。结果:大青叶水煎液对大肠杆菌的生长具有促进作用,且随着药液含量的增加,该促进作用逐渐增强。大青叶水煎液的5个化学部分对大肠杆菌生长的影响存在显著差异,其中水层部分能够刺激大肠杆菌的生长,而其他4个部分即石油醚部分、氯仿部分、醋酸乙酯和正丁醇部分对大肠杆菌的生长有不同程度的抑制作用,其抑制作用的大小依次为正丁醇部分>醋酸乙酯部分>氯仿部分>石油醚部分。结论:生物热力学的研究手段微量量热方法具有适用性广,便捷快速的优点,该方法的运用为中药的药效物质初筛提供了一个新的研究思路和方法。

Objective： To apply a novel method for screening the bioactive parts and substances of traditional Chinese medicines （TCM） based on biothermodyrnamic theories. Method： The power-time curves of Escherchia coli proliferation at different concentrations of decoction and its five bioactive parts of folium of Isatis indigotica （FII） were determined by TAM Air Isothermal Calorimeter. The growth rate constants of promotive and inhibitory actions were calculated. Moreover, the potential pharmacological action of FII was analyzed from the point of view of TCM theory. Result： The growth rate constant k1 and Pm of the studied bacterium in the presence of the decoction of FII were concentration-dependant. The kland Pm increased with the mass increase of the decoction and its water-extract of Fll. However, the value of k1 and Pm decreased with the increasing concentrations of its other four organic solvent parts. The experimental results revealod that the sequence of inhibitory activity of different extracts was n-BuOH extract 〉 EtOAc extract 〉 chloroform extract 〉 PE extract. Conclusion： The decoction and its water-extract of FII stimulated the metabolism of E. coli. While the other four organic solvent extracts of the total decection inhibited the growth of tested bacterium. The micrnealorimetric method has many virtues such as extensive applicability, convenience, ete, and provides a new and useful means for primary .screening the bioactive parts and substances of TCM.