## 3 Results and Discussion
### Fungal Isolation and Identification
The proteolytic activity of this fungus is particularly concerning in the context of this study, as it has been detected solely in the leather component of ANT.Moc.490. This activity poses a risk to collagen, a key component of leather, potentially leading to its degradation and compromising the artifact's overall integrity [61]. _Aspergillus chealieri_ has been previously isolated from limestone tombs, displaying deteriorative potential in this substrate [62]. Its proteolytic and cellulolytic abilities are also well established [51], the latter being of particular significance due to the nature of ANT.Moc.344, the artifact from where it was isolated. Also of significance is the strong orange pigment we observed in PDA culture media, which could lead to staining in more susceptible artifacts. As was the case for _A. pseudoglaucus_, this species is associated with health risks, namely cutaneous and cerebral aspergillosis, with its thermotolerant characteristics enabling invasion of deep tissue [58]. _Aspergillus conticus_ is also a known xerophilic contaminant of cultural heritage [63; 64]. _Aspergillus creber_'s biodeteriorative potential lies in its proteolytic and cellulolytic abilities [51], the former being cause for concern due to the artifact from where this species was isolated (MCUC.2013.1.3) being mostly made of animal skin. _Aspergillus proliferans_ was previously found contaminating canvas, easel paintings, archives and manuscripts [54], and possesses proteolytic abilities as well as the ability to produce a pale orange pigment [51; 56]. This pigment production was also observed on colonies growing on PDA culture media during this study. _Aspergillus ruber_ has already been reported as a contaminant of cultural heritage items such as paintings, paper and textiles [54; 65], but no further biodeteriorative potential is known for this species, having shown negative results for proteolytic, cellulolytic, calcium carbonate dissolution and pigment production assays [56]. As with _A. pseudoglaucus_, both _A. proliferans_ and _A. ruber_ have been associated with superficial human infections [58]. The _Penicillium_ genus was the second most abundant in this study, with two different species identified: _P. brevicompactum_ and _P. phoenicium_. As is the case for _Apergillus_, this genus is a frequent contaminant of indoor environments [56]. Of the two identified species, _P. phoenicium_, to the best of our knowledge, has no previous reports of contaminating cultural heritage or being involved in biodeterioration, and is classified as a cosmopolitan saprotrophic fungus [66]. _Penicillium brevicompactum_, on the other hand, has a well-established biodeteriorative potential, and is capable of calcium carbonate dissolution and mineralization, as well as producing a yellow-brown pigment, organic acids and enzymes with fibrinolytic, cellulolytic and proteolytic properties [51; 56], making it a serious threat to cultural heritage. Two different artifacts, ANT.Moc.349 and ANT.Moc.490 (in its leather components), led to the isolation of one species each that belong to the _Talromyces_ genus: _T. coalescens_ and _T. amestolkiae_, respectively. The first, similarly to _P. phoenicium_, has never been reported as a cultural heritage contaminant or biodeteriorant. It has, however, been recently reported as a potential causal agent for fungal keratitis [67]. As for _T. amestolkiae_, it has been previously reported contaminating limestone walls of the Old Cathedral of Coimbra [68], with biodeterioration capabilities including calcium carbonate dissolution and cellulolytic enzyme production, as well as pigment production [51; 68; 69].