Phenolic Components of Brown Scales of Onion Bulbs Produce Hydrogen Peroxide by Autooxidation
Phenolic Components of Brown Scales of Onion Bulbs Produce Hydrogen Peroxide by Autooxidation
复制标题
洋葱球茎棕色鳞片的酚类成分通过自动氧化产生过氧化氢
DOI：
10.1007/pl00014004
复制
发表时间：
2001
影响因子：
2.8
通讯作者：
S. Hirota
中科院分区：
文献类型：
--
作者：
U. Takahama;T. Oniki;S. Hirota
2 O2时，褐鳞屑悬浮于水中。从棕色鳞片中分离出的棕色组分也将分子氧转化为H2 O2。在自氧化过程中，可见光区的吸光度增加。在棕色部分的酸水解中，检测到2，4，6-三羟基苯乙醛酸、3，4-二羟基苯甲酸和苯甲酸的醌形式。此外，葡萄糖被检测为糖。在棕色馏分的自氧化过程中，3，4-二羟基苯甲酸优先被氧化。氧化产物之一是醌形式。在棕色组分中检测到稳定的电子自旋共振（ESR）信号。新的ESR信号出现在由hexacyanoferrate（III）的棕色馏分的氧化。其中一个新形成的自由基似乎具有3，4-二羟基苯基。在此基础上，对棕色组分的可能结构、H_2O_2生成机理及生物学意义进行了讨论。
2O2 when the brown scales were suspended in water. Brown components isolated from the brown scales also transformed molecular oxygen into H2O2. During the autooxidation process, absorbance in the visible region was increased. On acid hydrolysis of the brown fraction, 2,4,6-trihydroxyphenylglyoxylic acid, 3,4-dihydroxybenzoic acid and the quinone form of benzoic acid were detected. In addition, glucose was detected as a sugar. 3,4-Dihydroxybenzoic acid was preferentially oxidized during autooxidation of the brown fraction. One of the oxidation products was the quinone form. Stable electron spin resonance (ESR) signals were detected in the brown fraction. New ESR signals appeared on oxidation of the brown fraction by hexacyanoferrate (III). One of the newly formed radicals seemed to have a 3,4-dihydroxyphenyl group. Based on these results, possible structures, mechanism of H2O2 formation and biological significance of the brown components are discussed.