Green Chemistry and Archaeological Biomarkers: a new and safe DES-based approach for the extraction of absorbed lipid residues from archaeological samples of ceramic potsherds

摘要

This work aimed at comprehensively evaluate the potential and effectiveness of natural Deep Eutectic Solvents (DESs) for the extraction of different natural compounds from archaeological samples. We compared the procedure by DESs, which are now emerging as green and sustainable solvents, with the more conventional solvent extraction protocols, which gave measurable yields of lipid extract. The different techniques were applied on the absorbed residues of small samples of a replica pottery vessel after cooking experiments of animal fats. Direct extraction by DES and derivatization proved efficient to obtain enough fatty acids for quantification analysis of absorbed lipid residues by GC-MS. The next step was the application of DES extraction procedure on some archaeological samples previously submitted to conventional extraction methods. GC-MS analyses gave comparable results as regards the amounts and relative proportions of fatty acids identified in the archaeological samples, thus encouraging to further refine in the future the analytical protocol by DES.