Аналіз посмертних змін мікробіома людини

Abstract

The article presents the results of the thanatomicrobiome study from 18 corpses. Biomaterial for the study was selected in the Department of forensic examination of corpses in "Dnipropetrovsk Regional Bureau of Forensic Medicine" of the Dnipropetrovsk Regional Council during September 2020. Microbiological investigation was conducted at the Department of Microbiology, Virology and Biotechnology of Oles Honchar Dnipro National University. The purpose of the study was to determine the composition of the human thanatomicrobiome and its characteristic marker microorganisms for using it in forensics. Therefore, the task of this research was to study the characteristics of the postmortem microflora depending on age, sex, causes of death, post-mortem time of objects. Material and methods. To solve the assigned tasks such methods were used: microbiological, biochemical, physicochemical, statistical. Identification of microorganisms was conducted with using of selective and differential-diagnostic nutrient medium. Results and discussion. Among the isolated microorganisms in the thanatomicrobiome, the most common were represented by bacteria of genera Staphylococcus, Streptococcus, Enterococcus and family Enterobacteriaceae. Determining of thanatomicrobiome characteristics depending on sex was shown that the highest frequency of isolation for most bacterial species was found in men. The highest frequency of detection of microorganisms was observed on the first day after death. Staphylococcus spp. and Streptococcus spp. were presented in the postmortem microflora during all three days of observation, but frequency of their detection after 48 hours was significantly reduced. Salmonella spp. and Pseudomonas spp. were detected in the thanatomicrobiome only on the third day after death. In the study of the dependence of the microbiota on the causes of death, it was found that the frequency of Streptococcus spp. was higher in subjects who died from hanging, and bacteria of the genera Staphylococcus, Enterococcus, and Klebsiella were predominantly isolated from those who died of cardiovascular disorders. Bacteria of genera Staphylococcus, Streptococcus, Enterococcus, which together make up the vast majority of microorganisms was 64% in the oral cavity and 82% in the armpits should be considered as biomarkers of thanatomicrobiome. An indicative biomarker is also the increase of certain species of enterobacteria in the process of corpses destruction. Yeast and clostridia were specific markers of oral thanatomicrobiome. Conclusion. The composition of the thanatomicrobiome and its features may provide additional information about the conditions of death