According to our investigation carried out in July 2023, the wood of the Western Han Dynasty Dingtao M2 Tomb, stored in the preservation room, exhibited signs of microbial degradation. Our metagenomic analysis first revealed Penicillium as the dominant genus on the end of the wrapped wood. Furthermore, functional annotations demonstrated that the resident microbial community possessed cellulolytic and ligninolytic capabilities. Targeted metabolomic analysis evaluated the degradation capacity of Penicillium charlesii DTP₁, a strain isolated from the wrapped wood. We hypothesize that DTP₁ provides an acidic microenvironment via the production of organic acids; the functional microbial community then decomposes lignin into small metabolites via enzymatic action, and these products are then utilized by the microbial community, including DTP₁. Finally, we verified that liquid cinnamaldehyde and volatile gaseous allicin and carvacrol exhibit better inhibitory efficacy. Nevertheless, further optimization of plant-derived agents and application methods are still required. This study proposes a putative mechanism underlying the degradation of the Dingtao M2 Tomb wood by the microbial community, thereby providing theoretical support for the conservation of wooden cultural heritage and relics.
Wang et al. (Thu,) studied this question.