目的 分析板蓝根三氯甲烷提取部位抗内毒素作用的谱效关系，以阐明板蓝根药材药理活性与其物质基础间的相关性。方法 采用动态浊度法检测不同产地板蓝根三氯甲烷萃取物抗内毒素生物活性，得到板蓝根对内毒素抑制的量效关系曲线及其参数斜率（k、半数有效剂量（IC₅₀；采用HPLC色谱法获取板蓝根三氯甲烷部位指纹图谱，运用多元线性回归等统计方法，将抗内毒素活性参数IC₅₀与HPLC指纹图谱共有峰的标准化峰面积比值关联。结果 不同产地板蓝根三氯甲烷萃取物抗内毒素活性干扰实验最小稀释倍数为5倍；其量效关系直线k为48.64～55.19，说明各批次药材对内毒素的作用趋势相同；IC₅₀为0.260～1.099 g·mL-1，说明不同药材对内毒素的抑制作用差别较大；指纹图谱中与抗内毒素活性关系密切的峰为3，8和9。结论 板蓝根三氯甲烷部位有较好的体外抗内毒素作用，其中苯甲酸和其他2成分为其主要活性成分。

OBJECTIVE To analyze the spectrum-effect relationships between HPLC fingerprints and anti-endotoxin activity of the chloroform extract from Isatidis Radix， and to reveal the correlation between the pharmacological activity and material of herbs. METHODS The anti-endotoxin activity of the chloroform extract from Isatidis Radix was detected by kinetic turbidimetric assay. The concentration-response curve and parameters（k， IC₅₀were obtained. The fingerprints of the chloroform extract were investigated by HPLC method. The spectrum-effect relationships between the standardized peak area ratio of every characteristic absorption peak from HPLC fingerprints and the main anti-endotoxin activity parameters IC₅₀ from the responce curve were investigated by multiple linear regression. RESULTS The minimal dilution time of the interference test was 5. The k of the concentration-response curve of 10 batches of Isatidis Radix was 48.64-55.19， and the IC₅₀ was 0.260-1.099 g·mL-1. Peak 3， 8 and 9 had significant correlation with the anti-endotoxin activity. Benzoic acid and the other 2 constituents in the chloroform extraction part from Isatidis Radix were the main active components. CONCLUSION According to this in-depth research on the anti-endotoxin activity of the chloroform extract from Isatidis Radix， the relationship between chemical substances and effect is objectively clarified.