Müller-Enoch D, Seidl E, Thomas H
Z Naturforsch C Biosci. 1976 May-Jun;31(5-6):280-4.
6,7-Dihydroxycoumarin (Aesculetin) was found to be a substrate of rat liver Catechol-O-methylfransferase (COMT) (EC 2.1.1.6). Incubation of this substrate with S-Adenosyl-L-[methyl-14C]methionine and/or S-Adenosylmethionin-hydrogensulfate in the presence of COMT yields the highly fluorescent compounds 7-hydroxy-6-methoxycoumarin (Scopoletin) and 6-hydroxy-7-methoxycoumarin (Isoscopoletin) in the ration of about 2:1. The O-methylated products obtained from Aesculetin were identified after separation by thin layer chromatography mainly by the reversed isotope dilution technique. The fluorescence of the isolated methylethers was proportional to concentration within the range from 10(-5)-10(-7) M. A reciprocal plot of activity versus substrate concentration gives a Km of 1 X 10(-6) M.
6,7-二羟基香豆素（秦皮乙素）被发现是大鼠肝脏儿茶酚-O-甲基转移酶（COMT）（EC 2.1.1.6）的一种底物。在COMT存在的情况下，将该底物与S-腺苷-L-[甲基-¹⁴C]甲硫氨酸和/或S-腺苷甲硫氨酸硫酸氢盐一起孵育，会产生比例约为2:1的高荧光化合物7-羟基-6-甲氧基香豆素（东莨菪亭）和6-羟基-7-甲氧基香豆素（异东莨菪亭）。从秦皮乙素获得的O-甲基化产物在通过薄层色谱分离后，主要通过反向同位素稀释技术进行鉴定。分离出的甲基醚的荧光在10⁻⁵ - 10⁻⁷ M范围内与浓度成正比。活性与底物浓度的倒数作图得出Km为1×10⁻⁶ M。
