Abstract
The antioxidative ability of inosine 5'-monophosphate (IMP) and guanosine 5'-monophosphate (GMP) at various water activities (Aw, 0-0.75) and at 40°C was investigated. IMP and GMP exhibited antioxidative ability above Aw 0.25, and this ability was strongest at Aw 0.5. There was no obvious difference between the ability of IMP and GMP. IMP-related substances (hypoxanthine, inosine and ribose 5-phosphate) did not have antioxidative ability, suggesting that both the base and phosphate moieties of 5'-ribonucleotide are necessary to exhibit this ability. The ability of IMP and GMP was weaker than of 2, 6-di-tert-butyl-4-methylphenol (tert-butyl-hydroxytoluene; BHT) and ethylenediamine tetraacetic acid (EDTA). The possible mechanism for the antioxidative ability of IMP and GMP was assumed to be their chelating action.
