DNA-Based Detecton of Ethanol-Producing Microorganisms in Postmortem Blood and Tissues by Polymerase Chain Reaction

Forensic investigation of fatal aircraft accidents usually includes the analysis of biological samples for ethanol to establish if alcohol intoxication is a factor in the accidents. The quantitative aspects of ethanol are often complicated by postmortem putrefactive changes, leading to microbial fermentation-mediated production of alcohol and its subsequent redistribution. Without establishing the ethanol origin (antemortem consumption or postmortem production), a precise interpretation of the alcohol analytical results remains a challenge. Therefore, a DNA-based assay was developed using the polymerase chain reaction and microbial DNA primers designed for identifying 3 commonly encountered ethanol-producing microorganisms- Candialbicans, Proteus vulgaris, and Escherichia coli. The present study focused on examining the applicability of the microbial DNA primers in establishing the existence of postmortem alcohol in samples. The results suggested that species- specific primers could be employed to identify ethanol-producing microorganisms in forensic samples without requiring bacterial cultivation. Continued studies are warranted to define additional primer sequences that are distinctive for ethanol-producing microorganisms.