AbstractThe enzymic cooxidation of β‐carotene (BC) by xanthine oxidase (XO) in aqueous solutions leads to β‐ionone (BI) and derivatives: epoxy‐β‐ionone (EPBI), dihydroactinidiolide, β‐cyclocitral, pseudoionone, etc. We demonstrate, in this article, that this is due to free radical (R⋅) formation during the first hour of stirring and the use of aldehydes as substrate. The bleaching of BC does not occur when the common substrate of XO, xanthine, is used; this proves that the superoxide anion O2⋅‐alone is not active on BC. BI formation in this c
展开▼
机译：摘要黄嘌呤氧化酶（XO）在水溶液中对β-胡萝卜素（BC）进行酶促共氧化，得到β-紫罗兰酮（BI）及其衍生物：环氧-β-紫罗兰酮（EPBI）、二氢锕化物、β-环柠檬醛、假紫罗兰酮等。在本文中，我们证明这是由于在搅拌的第一个小时内形成自由基（R⋅）以及使用醛作为底物。当使用XO的共同底物黄嘌呤时，不会发生BC的漂白;这证明超氧阴离子 O2⋅‐ 单独在 BC 上没有活性。BI的形成在这个c
展开▼
