[关键词]
[摘要]
目的选取大肠杆菌做为工具菌,建立板蓝根不同萃取部位的生物热力学研究方法。方法采用微量热法测定大肠杆菌在板蓝根不同萃取部位作用下的生长热曲线特征谱图,得到相应的生物热动力学参数,评价板蓝根不同萃取部位的差异性。结果板蓝根不同萃取部位能够不同程度地抑制或促进大肠杆菌的生长,其中水提物、萃取后残渣促进其生长,而有机溶剂萃取物则抑制其生长;在热力学参数上表现为随着有机溶剂萃取物的极性降低,萃取物的抑制率下降、细菌传代时间延长;在生长热特征曲线上则表现为最大产热峰强度和对应的培养时间具有显著的差异,其中水提物、萃取后残渣的最大产热峰强度不变或略下降、达峰时间提前,有机溶剂萃取物的最大产热峰强度明显下降、达峰时间滞后,且存在特异的后期产热现象,可以较好的表征提取物间的差异性。结论微量热法可以较好的反映板蓝根的生物热力学参数及特征,该方法可为其他生物模型的研究提供参考和指导。
[Key word]
[Abstract]
Objective To establish the characteristic biothermokinetic methods in different extract fractions of Radix Isatis using Escherichia coli as model bacteria under biothermodynamics. Methods Microcalorimetry was used to obtain the characteristic metabolic growth power-time curves and biothermodynamic parameters of bacteria affected by different extract fractions of Radix Isatis, and evaluate the differences among the different extract fractions of Radix Isatis. Results Different extracting fractions of Radix Isatis could inhibit or promote the growth and metabolism of E. coli in different levels. Water-extract fractions and residues could promote its growth while organic solvent extract fractions did the opposite. Furthermore, with the decline of the solvent polarity, the inhibiting rate of organic solvent extract fraction was decreased and the generation time of bacteria was prolonged. There were steady and distinct differences among the different extract fractions in the characteristic metabolic growth power-time curves, such as the maximum power value's decrease and peak time's delay of water-extract fraction and residue, the specific power enhancement in later stage of organic solvent extract fraction. Conclusion Microcalorimetry is a new and useful mean for the study on the biothermodynamic parameters and characteristics of Radix Isatis which can be helpful to investigate the other models using microcalorimetry.
[中图分类号]
[基金项目]
国家中医药管理局面上项目(04-05ZP70)