Soil fungal community shift evaluation as a potential cadaver decomposition indicator. (December 2015)

• Record Type: Journal Article
• Authors: Chimutsa, Monica; Olakanye, Ayodeji O.; Thompson, Tim J.U.; Ralebitso-Senior, T. Komang
• Is Part Of: Forensic science international. Volume 257(2015)
• Page Start: 155
• Page End: 159
• Publication Date: 2015-12
• Subjects: Forensic ecogenomics -- Decomposition -- Fungal communities -- Soil -- PCR–DGGE; Medical jurisprudence -- Periodicals; Chemistry, Forensic -- Periodicals; Forensic Medicine -- Periodicals; Médecine légale -- Périodiques; Chimie légale -- Périodiques; Gerechtelijke geneeskunde; Gerechtelijke chemie; Gerechtelijke psychiatrie; Chemistry, Forensic; Medical jurisprudence; Electronic journals; Periodicals; Electronic journals; 614.1
• DOI: 10.1016/j.forsciint.2015.08.005
• Languages: English
• ISSNs: 0379-0738

Abstract

Highlights: Sus scrofa domesticus decomposition effected changes in fungal diversity. Decreased Simpson dominance index was recorded for the experimental microcosm. Unlike bacterial profiles, no statistically significant diversity shifts resulted. Longer on-going studies are testing 18S-DGGE applicability in forensic ecogenomics. Applicability is also being advanced with sequencing and in situ studies. Abstract: Fungi metabolise organic matter in situ and so alter both the bio-/physico-chemical properties and microbial community structure of the ecosystem. In particular, they are responsible reportedly for specific stages of decomposition. Therefore, this study aimed to extend previous bacteria-based forensic ecogenomics research by investigating soil fungal community and cadaver decomposition interactions in microcosms with garden soil (20 kg, fresh weight) and domestic pig ( Sus scrofa domesticus ) carcass (5 kg, leg). Soil samples were collected at depths of 0–10 cm, 10–20 cm and 20–30 cm on days 3, 28 and 77 in the absence (control −Pg) and presence (experimental +Pg) of Sus scrofa domesticus and used for total DNA extraction and nested polymerase chain reaction and denaturing gradient gel electrophoresis (PCR–DGGE) profiling of the 18S rRNA gene. The Shannon–Wiener ( H ′) community diversity indices were 1.25 ± 0.21 and 1.49 ± 0.30 for the control and experimental microcosms, respectively, while comparable Simpson species dominance ( S ) values were 0.65 ± 0.109 and 0.75 ± 0.015. Generally, and in contrast to parallel studies of the bacterial 16S rRNA and 16S rDNA profiles, statistical analysis ( t -test) of the 18S dynamics showed no mathematically significant shifts in fungal community diversity ( H ′; p = 0.142) and dominance ( S ; p = 0.392) during carcass decomposition, necessitating further investigations.