Odo Junichi, Torimoto Sei-ichi, Nakanishi Suguru, Niitani Tomoya, Aoki Hiroyuki, Inoguchi Masahiko, Yamasaki Yu
Department of Biochemistry, Faculty of Science, Okayama University of Science, Ridai-cho 1–1, Kita, Okayama, Japan.
Chem Pharm Bull (Tokyo). 2012;60(7):846-53. doi: 10.1248/cpb.c12-00114.
The photodegradation of environmental mutagens, such as 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1), 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2), 2-amino-3-methyl-9H-pyrido[2,3-b]indole (MeAαC), and 2-amino-3-methyl-imidazo[4,5-f]quinoline (IQ), was investigated by visible irradiation in the presence of xanthene dyes as photosensitizers. Although the environmental mutagens themselves were very stable during visible irradiation under the conditions in this study, they were effectively photodegraded in the presence of the xanthene dyes (erythrosine, rose bengal, and phloxine). Moreover, photodegradation of the mutagens was further enhanced for xanthene dyes loaded onto a water-soluble diethylaminoethyl (DEAE)-dextran anion-exchanger via ionic interactions (xanthene-dyeDEX). Photodegradation was inhibited by O2 removal from the reaction solution. In ESR spin-trapping experiments using 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) as a trapping reagent, signals characteristic of DMPO-•OH (hydroxyl radical) were observed in the presence of xanthene-dyeDEX. These results suggest that reactive oxygen species derived from O2, such as singlet molecular oxygen (•1O2) and/or •OH, were active participants in photodegradation of the mutagens in the presence of xanthene dyes or xanthene-dyeDEX.
在以呫吨染料作为光敏剂的可见光照射下，研究了环境诱变剂3-氨基-1,4-二甲基-5H-吡啶并[4,3-b]吲哚（Trp-P-1）、3-氨基-1-甲基-5H-吡啶并[4,3-b]吲哚（Trp-P-2）、2-氨基-3-甲基-9H-吡啶并[2,3-b]吲哚（MeAαC）和2-氨基-3-甲基-咪唑并[4,5-f]喹啉（IQ）的光降解。尽管在本研究条件下可见光照射期间环境诱变剂本身非常稳定，但在呫吨染料（赤藓红、孟加拉玫瑰红和荧光素）存在下它们能被有效光降解。此外，通过离子相互作用负载在水溶性二乙氨基乙基（DEAE）-葡聚糖阴离子交换剂上的呫吨染料（呫吨染料-DEX）能进一步增强诱变剂的光降解。从反应溶液中除去O2会抑制光降解。在使用5,5-二甲基-1-吡咯啉-N-氧化物（DMPO）作为捕获试剂的电子自旋共振（ESR）自旋捕获实验中，在呫吨染料-DEX存在下观察到了DMPO-•OH（羟基自由基）的特征信号。这些结果表明，在呫吨染料或呫吨染料-DEX存在下，源自O2的活性氧物种，如单线态分子氧（•1O2）和/或•OH，是诱变剂光降解的积极参与者。
