Date of Award
Doctor of Philosophy
Dr. Shawn R Campagna
Shawn R Campagna, Dawnie Steadman, Apofo Darko, Ziling (Ben) Xue
By focusing on solely forensic studies, this dissertation gives an overview of three seemingly independent studies, which at a deeper level, reveal their strong interconnectivity through their forensic importance. The consistent global theme carried through all chapters circles around the application of metabolomics on biological specimens collected postmortem at an outdoor taphonomy facility in Knoxville, Tennessee, USA. The overall intention was to fill the knowledge gap around postmortem metabolomics while stressing its importance in bridging analytical chemistry and forensic science. Global postmortem metabolomics studies will contribute to the so-far conducted taphonomic groundwork by providing a better understanding of the fundamental processes of decomposition and ultimately build a more comprehensive postmortem biochemical database.
The first chapter applies postmortem metabolomics to soils and human skeletal remains obtained from a multi-individual grave. The primary goals of this study were: (1) to obtain insights into the metabolite pulse released from buried remains into grave soils at different depths of a shallow burial and (2) to assess metabolic signatures of bones using an inter- and intraindividual analysis approach.
Decomposition progresses differently below ground compared to the soil surface with impacts on rates and patterns of decomposition. In contrast to the first chapter, the second chapter faces an environmental change with a study design constructed around surface decomposition. Additionally, given that rates and patterns of decay seem to vary among species, a comprehensive omics approach including metabolomics and lipidomics was utilized to investigate species-specific metabolic signatures in soils from the cadaver decomposition island.
The final chapter completes the aforementioned studies by investigating one of the most complex of all factors – intrinsic drivers of decomposition. We evaluated the trackability of drugs through several specimens such as serum, larvae, decomposition fluid, and soils from human donors. Furthermore, comprehensive postmortem metabolomics of the same specimens provided (a) matrix-specific metabolic signatures, (b) groups of metabolites potentially useful as decomposition biomarkers, and (c) an assessment of possible impacts of perimortem health conditions on the postmortem metabolome.
Hoeland, Katharina Melanie, "Investigating the Potential of Postmortem Metabolomics in Mammalian Decomposition Studies in Outdoor Settings. " PhD diss., University of Tennessee, 2021.