Myco- and microbiological profiling of a human cadaver reveals drug-resistant strains and new fungal records.

In this study, the composition of the postmortem mycobiome and microbiome of a cadaver in an advanced stage of decomposition, had been deposited outdoors and showed extensive mycelial growth, was characterized using culture methods. This approach allowed for the identification of a total of 26 fungal and 16 bacterial species. The dominant fungal species were Penicillium polonicum, Debaryomyces hansenii, and Penicillium commune. Sensitivity tests for voriconazole and amphotericin B were also performed, to which several isolates were resistant. In the case of bacteria, the distribution of dominant species differed between samples taken from outside the body and samples taken from inside the body. Sensitivity tests for 16 antibiotics showed that 23.08% of isolates were resistant to the tested drugs. Importantly, to the best of our knowledge, we detected several species that have not been previously associated with cadavers: Botryotrichum domesticum, Chaetomium subaffine, Penicillium allii, Scopulariopsis crassa, Scopulariopsis fusca and Yarrowia deformans. These results not only expand our understanding of the ecological roles of fungi in cadaver decomposition but also highlight their potential forensic value. First and foremost, it broadens our understanding of local fungal communities associated with human remains, which in the future may provide valuable information about the location or environmental conditions of body deposition, while specific taxa could assist in estimating the postmortem interval. Moreover, the identification of drug-resistant strains underscores the importance of biosafety in forensic practice and raises awareness of the potential for pathogen dissemination from decomposing remains. KEY POINTS: • Twenty-six fungi and sixteen bacterial species were identified from the cadaver • New fungal records isolated from human remains, expanding forensic mycology knowledge • Antimicrobial susceptibility testing revealed the presence of drug-resistant fungal and bacterial isolates.