STUDIES ON THE ASYMMETRIC DECOMPOSITION OF D,L-LEUCINE INDUCED BY ~(60)Co γ-IRRADIATION

Sublimed D-,L-,and DL-leucine under vacuum were subjected to ~(60)Co γ-irradiation withdifferent doses.The enantiomeric compositions of samples were determined by chirasil-val capillary column gas chromatography,and the relative yields of radiolytic products(H_2,CO_2 and NH_3)were measured by packed column gas chromatography.The obtained datashowed the peak area ratios D/L of DL-leucine after different absorbed doses of irradiationare all the same as that of samples with no irradiation,within the limit of error.So are theratios for the separately irradiated D-and L-leuicne.This suggests that no asymmetric decom-position was found.The relative yields D/L of radiolytic products(H_2,CO_2 and NH_3)arevery close to 1.00,indicating that the D-leucine cleavage rate was the same with that of theL-leucine.From the view of dissipative structure,an explanation for the result was presented.