Biochemical Pathways Generating Post-Mortem Volatile Compounds Co-Detected During Forensic Ethanol Analyses

• NCJ Number: 222196
• Journal: Forensic Science International Volume: 174 Issue: 2-3 Dated: January 2008 Pages: 133-151
• Author(s): Vassiliki A. Boumba; Kallirroe S. Ziavrou; Theodore Vougiouklakis
• Date Published: January 2008
• Length: 19 pages
• Publication Format: Article
• Publication Type: Report (Study/Research)
• Language: English
• Country: United States of America

Annotation

This paper identifies and describes the microbial biochemical pathways that generate the volatile compounds detected in decaying corpses during the forensic ethanol analysis.

Abstract

Many species of bacteria, yeast, and fungi that may invade a body after death have been determined to produce ethanol. This paper lists the bacteria species believed to be the major colonizers in corpses and also the main ethanol producers. The following volatile compounds created through microbial biochemical pathways have been detected in corpses through ethanol analysis: ethanol, acetaldehyde, acetone, 2-propanol, 1-propanol, 1-butanol, isobutanol, isoamyl alcohol, d-amyl alcohol, acetic, propionic, butyric and isobutyric acids, and ethyl esters (mainly ethyl acetate). These volatiles result from the fermentation of the main substrates present in a putrefying corpse, namely, carbohydrates, amino acids, glycerol, and fatty acids. The forensic literature reports the detection of only a few volatiles compared with the spectrum of volatiles that could be formed. Besides ethanol, most of these studies have detected 1-propanol, acetaldehyde, acetone, 2-propanol, isobutanol, and 1-butanol. These volatiles have been considered biochemical markers for a corpse flagged as suspicious for microbial contamination if present in abnormally high concentrations; however, the studies do not define the measure of "abnormally high concentrations." Corpses in various stages of putrefaction, depending on environmental conditions, are attacked by different microbial species whose action results in the formation of variable and unpredictable volatile levels. Also, the deceased's pre-death consumption of alcoholic beverages could result in detectable amounts of volatiles along with microbial ethanol amounts after death. The authors advise that future studies should establish the minimum volatile levels that could indicate microbial contamination and subsequent ethanol products, along with the correlation of these levels with the ethanol concentration produced and possibly the stage of putrefaction. 1 table, 9 figures, and 150 references