Photodegradation of environmental mutagens by visible irradiation in the presence of xanthene dyes as photosensitizers.
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.
Department of Biochemistry, Faculty of Science, Okayama University of Science, Ridai-cho 1–1, Kita, Okayama, Japan. odo@dbc.ous.ac.jp
Junichi
J
Odo
Sei-ichi
S
Torimoto
Suguru
S
Nakanishi
Tomoya
T
Niitani
Hiroyuki
H
Aoki
Masahiko
M
Inoguchi
Yu
Y
Yamasaki
D003637:DEAE-Dextran / Q000737:chemistry; D004578:Electron Spin Resonance Spectroscopy; D004923:Erythrosine / Q000737:chemistry; D005452:Fluoresceins / Q000737:chemistry; D005456:Fluorescent Dyes / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000737:chemistry; D017665:Hydroxyl Radical / Q000737:chemistry; D007211:Indoles / Q000737:chemistry; D008027:Light; D009153:Mutagens / Q000737:chemistry*; D010782:Photolysis; D017319:Photosensitizing Agents / Q000737:chemistry*; D011804:Quinolines / Q000737:chemistry; D012395:Rose Bengal / Q000737:chemistry; D026082:Singlet Oxygen / Q000737:chemistry; D014966:Xanthenes / Q000737:chemistry*
D005452:Fluoresceins; D005456:Fluorescent Dyes; D007211:Indoles; D009153:Mutagens; D017319:Photosensitizing Agents; D011804:Quinolines; D014966:Xanthenes; D026082:Singlet Oxygen; D012395:Rose Bengal; D017665:Hydroxyl Radical; D003637:DEAE-Dextran; D006861:Hydrogen Peroxide; D004923:Erythrosine; C085059:phloxine