基于生物热动力学的拳参对大肠埃希菌抑制作用

Antibacterial Effect Evaluation of Bistortae Rhizoma Against Escherichia coli by Microcalorimetry

目的：测定不同产地、不同颜色拳参对大肠埃希菌生长代谢的影响,从生物热力学角度研究拳参对大肠埃希菌的抑制作用。方法：用微量热法测定18批拳参作用于大肠埃希菌生长代谢的热谱曲线,取得达峰时间（t1,t2）,最大产热功率（Pmax1,Pmax2）,生长速率常数（k1,k2）,抑制率（I）4个主要参数。结果：河北、山东、安徽产拳参可延长大肠埃希菌第二指数生长期达峰时间（t2）,降低最大产热功率（Pmax2）及生长速率（k2）,湖北产拳参与其他产地样品趋势不同;各产地拳参对第一指数生长期的峰时间（t1）,降低最大产热功率（Pmax1）及生长速率（k1）均无影响。不同产地拳参样品对大肠埃希菌抑制率不同（I）,河北、山东、安徽产拳参抑制率在20%～50%,湖北拳参样品抑制率较低。同一批次不同颜色拳参样品抑制率有差异,9个批号样品中,7批棕红色饮片抑制率高于紫红色饮片。结论：不同产地棕红色及紫红色拳参对大肠埃希菌的生长代谢曲线均有不同程度的抑制作用,其差异原因有待进一步研究。

Objective： To study the effect of Bistortae Rhizoma from different production places and colors on growth metabolism of Escherichia coli,and investigate its inhibitory effect on E. coli from the standpoint of biological thermodynamics. Method： The thermal spectrum curve reflecting the growth and metabolism of E.coli affected by 18 batches of Bistortae Rhizoma was determined by using microcalorimetry. Then the quantitative thermokinetic parameters, such as peak time（ t1,t2）,maximum heat-output（ Pmax1,Pmax2）,growth rate constant（ k1,k2）,and inhibition rate（ I） obtained from these curves were analyzed. Result： Bistortae Rhizoma from Hebei,Shandong and Anhui could prolong the peak time of E. coli in the second growth exponential period（ t2）,and reduce the maximum thermal power（ Pmax2） and growth rate（ k2）,different from the samples from Hubei. All samples from four production places had no influence on the parameters（ t1,Pmax1,and k1） in first growth exponential period. Bistortae Rhizoma from different production places showed different I values on E. coli,between 20%-50% for the samples from Hebei,Shandong and Anhui,while the I value was lower for the samples from Hubei. The Bistortae Rhizoma samples from the same batch but with different colors also showed difference in inhibitory rate. A total of 7 batches of brownish red Bistortae Rhizoma showed higher inhibition rate（ I） than its prunosus ones in all 9 batches. Conclusion： The Bistortae Rhizoma from different places and colors have different degrees of inhibitory effect on the growth and metabolism of E. coli,and the factors leading to the difference still need further study.