Dabrowski K
Zoologisches Institut, Universität Innsbruck.
Biol Chem Hoppe Seyler. 1990 Mar;371(3):207-14. doi: 10.1515/bchm3.1990.371.1.207.
Data in the literature imply that some fish species evolved with the capacity to synthesize ascorbic acid. Gulonolactone oxidase activity has been reported in kidney and/or liver tissues. However, it is shown here that this microsomal enzyme activity is missing in common carp hepatopancreas and kidney, whereas high activity was confirmed in pigeon kidney, rat liver, bovine liver and amphibian (Xenopus) kidney tissues. A new assay using either the whole tissue homogenate or microsomes solubilized by sodium deoxycholate was developed to directly measure the formation of ascorbic acid spectrophotometrically. Identical values were found using this assay as well as the assay in which formed ascorbate was determined by the dinitrophenyl hydrazine (DNPH) method. In some experiments, these results were confirmed by polarographically measured oxygen consumption.
文献中的数据表明，一些鱼类物种进化出了合成抗坏血酸的能力。已报道在肾脏和/或肝脏组织中存在古洛糖酸内酯氧化酶活性。然而，本文表明，这种微粒体酶活性在鲤鱼肝胰腺和肾脏中缺失，而在鸽肾、大鼠肝脏、牛肝脏和两栖动物（非洲爪蟾）肾脏组织中证实有高活性。开发了一种新的检测方法，使用全组织匀浆或用脱氧胆酸钠溶解的微粒体，通过分光光度法直接测量抗坏血酸的形成。使用该检测方法以及用二硝基苯肼（DNPH）法测定生成的抗坏血酸盐的检测方法，得到了相同的值。在一些实验中，这些结果通过极谱法测量的耗氧量得到了证实。
