Ikegami F, Matsunae K, Hisamitsu M, Kurihara T, Yamamoto T, Murakoshi I
Research Center of Medical Resources, Faculty of Pharmaceutical Sciences, Chiba University, Japan.
Biol Pharm Bull. 1995 Nov;18(11):1531-4. doi: 10.1248/bpb.18.1531.
beta-D-Glucuronidase (baicalinase, GUS [EC 3.2.1.31]) activity in the crude drug, Scutellaria root, was assayed in line with the quality control standards of Kampo (Japanese Herbal) medicines. GUS was purified to homogeneity in the purification steps including DEAE-Sepharose Fast Flow and chromatofocusing used PBETM94 and Polybuffer 74. These results suggest that the Scutellaria GUS is composed of 55kDa active subunits and that the isoelectric point of this enzyme is pH 5.4. Optimal catalytic activity was found at pH 4.7 in the pH range 3.6--6.2 in 50 mM Na-citrate buffer. The purified enzyme hydrolyzed baicalin and wogonin glucuronide, but did not hydrolyze glycyrrhizin or some beta-glucosides found in other crude drugs. GUS activity in several crude drugs is also described.
按照汉方药（日本草药）的质量控制标准，对生药黄芩根中的β-D-葡萄糖醛酸酶（黄芩苷酶，GUS [EC 3.2.1.31]）活性进行了测定。在包括DEAE-琼脂糖快速流动和使用PBETM94和Polybuffer 74进行色谱聚焦的纯化步骤中，将GUS纯化至同质。这些结果表明，黄芩GUS由55kDa活性亚基组成，该酶的等电点为pH 5.4。在50 mM柠檬酸钠缓冲液中，在3.6-6.2的pH范围内，在pH 4.7时发现最佳催化活性。纯化的酶水解黄芩苷和汉黄芩苷葡萄糖醛酸，但不水解甘草甜素或其他生药中发现的一些β-糖苷。还描述了几种生药中的GUS活性。
