For the estimation of age, the measuring of D/L ratio in racemization of aspartic acid(Asp) in human dentine can be used and it estimates age more accurate than the conventional physiological methods. In the natural state, the optical isomers of
amino
acid slowly undergo spontaneous, nonenzymatic recemization, so the detectable amount of D-enantiomer will be formed from pure L-isomer in dentine. This fact can be used to determine the age of living human and animals or the age of fossil bones.
This
study, therefore, was measured D/L ratio of aspartic acid in human acid in human dentines to estimate the age of each individual.
The correlation or D/L ratio of aspartic acid with actual age was obtained was follows,
The correlation value between the D/L ratio and the actual age was 0.9886, the standard estimateddeviation(σ) was 2.07 years of age and the k(yr-1) was 8.0×10-4. The actual and the estimated ages coincided in 23% of the cases. The errors of ±1
year
were 15%, that of ±2 years were 40%, ±3 years 15%, ±4 years 4%,respectively.Errors of exceeding 5years were not obtained.
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