中文摘要：

开发药用植物首先必须确定其活性部位.我们采用微量热法鉴定了一种植物Vitex negundo Linn的四种不同提取物：正己烷提取物、氯仿提取物、乙酸乙酯提取物和甲醇提取物对大肠杆菌（E.coli）的抑制作用.结果表明甲醇提取物对大肠杆菌生长的代谢热谱抑制作用最强.通过计算该提取物作用下大肠杆菌的生长速率常数,表明该提取物的抑制作用随浓度的升高而增强.

英文摘要：

Identification of the active position is the first step in the exploration of medical herbs. The effects of four Vitex negundo Linn extracts： n-hexane extracts, chloroform extracts, ethyl acetate extracts, and methanol extracts on Escherichia coli （E. coli） were investigated by microcalorimetry. The methanol extracts displayed strongest influence on the thermogenic growth curves of E. coli. The ethyl acetate extracts displayed lower influence than the methanol extracts. The n-hexane extracts and chloroform extracts displayed no obvious influence. The growth rate constants of E. coli and inhibition ratio under the actions of methanol and ethyl acetate extracts were calculated. Their inhibitory effects increased with concentrations.