Pulse radiolytic study of alpha-tocopherol radical mechanisms in ethanolic solution.

Pulse radiolytic studies of alpha-tocopherol (alpha TH) oxidation-reduction processes were carried out with low doses (5 Gy) of high-energy electrons in O2-, N2-, and air-saturated ethanolic solutions. Depending on the concentration of oxygen in solution, two different radicals, A . and B ., were observed. The first, A ., was obtained under N2 and results from alpha TH reaction with solvated electron (k alpha TH + e-solv = 3.4 X 10(8) mol-1 liter s-1) and with H3C-CH-OH, (R.) (k alpha TH + R. = 5 X 10(5) mol-1 liter s-1). B., observed under O2, is produced by alpha TH reaction with RO2 . peroxyl radicals (k alpha TH + RO2 . = 9.5 X 10(4) mol-1 liter s-1).