间接水解法测定含甲氧基黄酮UGT代谢物的摩尔消光系数转化因子

摘要

OBJECTIVE: To establish the method for the determination of conversion factors (K) of molar extinction coefficients for methoxylated flavonoids glucuronides. METHODS: Indirect hydrolysis method was applied to determine the conversion factors (K) for glucuronides of wogonin, tectochrysin, eupatorin, 5-hydroxy-7,8-dimethoxyflavone. As wogonin and wogonoside (glucuronide of wogonin) were both commercially available, wogonoside conversion factor could be also derived directly, and the derived result could investigate the accuracy of indirect method. RESULTS: The conversion factors of above flavonoids glucuronides were derived respectively to be (1.05 ± 0.03) , (1.47 ± 0.09), (1.04 ± 0.04) and (1.25 ± 0.09) by indirect method, and wogonoside conversion factor was derived to be (1.03 ± 0.02) by direct method, which was close to results of indirect method. CONCLUSION: The common indirect hydrolysis method could be used for the conversion factor determination and provide more precise quantification for flavonoids glucuronides.rnIndirect hydrolysis; Methoxylated flavonoids; Glucuronides; Molar extinction coefficient; Conversion factor; Determination%目的:建立测定含甲氧基黄酮尿苷二磷酸葡萄糖醛酸转移酶(UGT)代谢物转化为相应苷元的摩尔消光系数转化因子(K)的方法,实现对无对照品代谢物的准确定量.方法:以间接水解法测定含甲氧基黄酮汉黄芩素、杨芽黄素、泽兰黄素及5-羟基-7,8-二甲氧基黄酮的UGT代谢物K值;且因汉黄芩素及其UGT代谢物汉黄芩苷均有对照品,采用两对照品直接测定汉黄芩苷K值以验证间接水解法的准确性.结果:间接水解法测得上述含甲氧基黄酮UGT代谢物的K值分别为(1.05±0.03)、(1.47±0.09)、(1.04±0.04)、( 1.25±0.09),直接测定汉黄芩苷的K值为(1.03±0.02),与间接法所测K值相近.结论:采用间接水解法测定K值可准确对无对照品黄酮化合物UGT代谢物进行定量.