Brief communication: Mass spectroscopic characterization of tetracycline in the skeletal remains of an ancient population from Sudanese Nubia 350-550 CE.

Histological evidence of tetracycline use has been reported in an ancient X-Group population (350-550 CE) from Sudanese Nubia (Bassett et al., 1980). When bone samples were examined by fluorescent micros- copy under UV light at 490 Ayellow-green fluorophore deposition bands, similar to those produced by tetracy- cline, were observed, suggesting significant exposure of the population to the antibiotic. These reports were met skeptically with claims that the fluorescence was the result of postmortem taphonomic infiltration of bacteria and fungi. Herein, we report the acid extraction and mass spectroscopic characterization of the antibiotic tetracy- cline from these samples. The bone samples were demine- ralized in anhydrous hydrogen fluoride which dissolved the bone-complexed tetracycline, followed by isolation by solid phase extraction on reverse-phase media. Chemical characterization by high pressure liquid chromatography mass-spectroscopic procedures showed that the retention times and mass spectra of the bone extract were identical to tetracycline when treated similarly. These results indi- cate that a natural product tetracycline was detectable within the sampled bone and was converted to the acid- stable form, anhydrotetracycline, with a mass 1 Ho f 427.1 amu. Our findings show that the bone sampled is labeled by the antibiotic tetracycline, and that the NAX population ingested and were exposed to tetracycline-con- taining materials in their dietary regime. Am J Phys Anthropol 143:151-154, 2010. V C 2010 Wiley-Liss, Inc.