The relationship between superoxide and singlet oxygen in PSⅡ particle of spinach under strong illumination was studied with spin-trap ESR technique. The generation of superoxide was increased under D 2O environment which prolonged the half life of singlet oxygen. The generation of superoxide was decreased when histidine existed as a scavenger of singlet oxygen. It is highly possible that the superoxide generated in PSⅡ particle originates from singlet oxygen.
The synthesis of a novel α phosphorus containing spin trap, DEPDMPO(5 diethoxy Phosphoryl 2, 5 dimethyl 1 pyrroline \%N\% oxide) and the evaluation of its ability to spin trap the hydroxyl and the superoxide anion radicals were described in the present article. The ability to trap an active superoxide anion radical generated in the photo system Ⅱ(PSII) and the stability of their spin adduct of DEPDMPO as well as three previously reported traps DMPO, DEPMPO and M 3PO were comparatively analyzed according to their chemical structures. In addition, the effects of 2 methyl and \%α\% phosphoryl substituted analogues of DMPO on the stabilities of the corresponding spin adduts were systematically
Synthesis of a novel α phosphorus containing spin trap, DEPPEPO[5 (diethoxyphosphoryl) 5 phenylethyl 1 pyrroline] N oxide and evaluation of its ability to spin trap the hydroxyl and the superoxide anion radicals were described in the present article. The ability for trapping an active superoxide anion radicals generated in the HX/XO system and the stability of their spin adduct of DEPPEPO were analyzed. In addition, the effects of 5 phenylethyl and 5 phenyl substituted analogues of DMPO on the stereochemistry of the corresponding spin adducts were systematically illustrated.
