抄録
An intermediate radical, CH2OH, was produced in aqueous methanol solution containing nitrous oxide by γ-irradiation.Yields of ethylene glycol and formaldehyde, the major and the minor product from CH2OH, respectively, changed on the addition of some solutes. Cysteine lowered the both product yields to zero even at a low concentration of 5×10-5M. Oxygen of low concentrations (2.5 7.5×10-5M) changed effectively the major product from ethylene glycol to formaldehyde as shown in Fig. 4. k(CySH+CH2OH)/k(O2+CH2OH) was calculated as 0.5 from the straight line in Fig.5.
Ascorbic acid (5×10-5M) lowered ethylene glycol yield to 48%, cystine (10-3M) to 15%, methionine (10-3M) to 31%, histidine (10-3M) to 42%, tryptophan (10-3M) 46%, tyrosine (10-3M) to 77%, phenylalanine (10-3M) to 73%, hypoxanthine (10-3M) to 37%, adenine (10-3M) to 52%, uracil (10-3M) to 20%, thymine (10-3M) to 10%, cytosine (10-3M) to 49%, rutin (10-3M) to 23%, pyrogallol (10-3M) to 41%, and gallic acid (10-3M)to 78% of the control as shown in Fig. 6 and listed in Table I.
These results suggest that the reactions of the secondary radicals such as CH2OH perform an important role in material change of foods irradiated with γr rays.
(Abstracted from the original paper which appears in Agr. Biol. Chem. 33, 250 (No.2), 1969).