Establishment of a novel preliminary screening model for bioactive parts of folium of Isatis indigotica based on biothermodynamics / 中国中药杂志

ABSTRACT

<p><b>OBJECTIVE</b>To apply a novel method for screening the bioactive parts and substances of traditional Chinese medicines (TCM) based on biothermodynamic theories.</p><p><b>METHOD</b>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.</p><p><b>RESULT</b>The growth rate constant k1 and Pm of the studied bacterium in the presence of the decoction of FII were concentration-dependant. The k1 and Pm increased with the mass increase of the decoction and its water-extract of FII. However, the value of k1 and Pm decreased with the increasing concentrations of its other four organic solvent parts. The experimental results revealed that the sequence of inhibitory activity of different extracts was n-BuOH extract > EtOAc extract > chloroform extract > PE extract.</p><p><b>CONCLUSION</b>The decoction and its water-extract of FII stimulated the metabolism of E. coli. While the other four organic solvent extracts of the total decoction inhibited the growth of tested bacterium. The microcalorimetric method has many virtues such as extensive applicability, convenience, etc, and provides a new and useful means for primary screening the bioactive parts and substances of TCM.</p>