Study of cell protective effects of alcohols against UV-C radiation and comparison to gamma radiation

Abstract A singlet oxygen production was monitored using a singlet oxygen sensor green chemical probe; reaction of chemical probe with singlet oxygen produces a fluorescent endoperoxide. Adding ethanol to the irradiated system resulted in decrease of the fluorescence signal, which indicates a decrease in concentration of singlet oxygen formed under UV-C irradiation. Thus, ethanol was likely to quench singlet oxygen in a system under study. This quenching did not occur with the use of methanol. When irradiating E. coli cells in the presence of ethanol and Rose Bengal for higher singlet oxygen production, there was a greater reduction in the radiation sensitivity of the cells compared to the system without Rose Bengal. Higher concentration of ethanol caused greater protection of cells; thus, it is likely that ethanol can scavenge singlet oxygen and provide a partial protection of bacteria from the effects of UV-C radiation. These results were compared with previously published data where the bacteria were irradiated by gamma radiation in presence of alcohols.