Achaeometrical Research in Hungary II., 1988

BIBLIOGRAPHY - SUMMARIES - DATING

because of the large differences between radiocarbon dating and amino acid dating, we would like to emphasise that the higher Age data acquired from amino acid dating may be due to diaminopimelic acid of bacterial origin. Following the development of an analytical method, it was applied to the determination of the bacterial proteins prepared from the rumen fluid and from fossil bone samples. By This new method the DAPA content of the fossil bone can be determined and the D-alloisoleucine content of the fossil bones, determined by the traditionally amino acid analysis, can be corrected with the amount of the DAPA. In This manner after the correction of Dallo-isoleucine content with DAPA, the Age of fossil bones will be less, and will be similar to ages determined by the radiocarbon method. Csapó J., Csapó-Kiss Zs., Költő L., Némethy S.: Age estimation of materials with high keratin content based on cystine, cysteic acid, methionine and tyrosine content. Archaeological Sciences Conference, Liverpool, England, July 3-6 (1995) 47. A method for evaluation of Age of wool carpets and textiles was developed based on the Age dependent alteration of amino acid composition of proteins. Samples of 23 wool carpets and textiles of known Age obtained from different Hungarian Museums were analysed for amino acid content. Results were compared with data obtained for contemporary, untreated wool and wool carpet samples. The cysteic acid content of wool increased with Age. The contemporary wool carpet contained 0.31 g of cysteic acid in 100 g of protein. Comparable figures were 1.87 g for 550-year old carpet and 4.01-4.39 g for the 1600-1750-year old wool carpets. Cystine content decreased with Age corresponding figures being 7.88, 3.12, 1.19-0.97, respectively. Corresponding contents of methionine were 0.43, 0.21, and 0.20-0 and for tyrosine were 3.07, 2.11 and 0.20-0. Prediction equations were developed as linear regressions of Age of wool and hair on cysteic acid, cystine and tyrosine contents. The 95% confidence intervals of estimates for two samples of unknown Age were estimates plus or minus 30 and 38 years. Csapó J., Csapó-Kiss Zs.: Radiocarbon calibration for dating based on amino acid Racemization: Newest Results on the field of Age determination of fossil bone samples = International Symposium on Archaeometry, Urbana-Champaign, USA, May 20-24 (1996). A method was developed to determine the Age of fossil bone samples based on amino acid Racemization (AAR). Approximately one hundred fossil bone samples of known Age from Hungary were collected and analysed for D- and L- amino acids. As the Racemization of amino acids is affected by temperature, pH, metal content of the Soil, and time passed since death, These factors were eliminated by comparing the estimated Age to Age determined by the radiocarbon method. Determining the D- and L- amino acid contents in samples of known Age, determining the half life of Racemization and plotting the D/L ratio as a function of time, calibration curves were obtained. These curves can be used for the Age estimation of samples after determining their D- and Lamino acid content. The D/L ratio for 2 to 3 amino acids was determined for each sample and the mean value of estimated ages based on calibration curves was considered the best estimate of Age of the fossil sample. 282