## 1 Introduction  
Cultural heritage is an important part of all societies and cultures. In its various forms, be it monuments, paintings, sculptures, books or other artifacts, it allows for a deeper understanding of past events and experiences, connecting past and present in a unique and extremely educational way. However, cultural heritage monuments, sites and artifacts are constantly under threat of deterioration from multiple threats, such as air pollution, with several gases, particulate matter and acid rainfall having corrosive effects on monumentsand other culturally significant structures exposed to such conditions [1]. However, one more complex and ubiquitous form of deterioration is caused by the activity of living organisms, a phenomenon commonly known as biodeterioration. This can be caused by several types of organisms, such as archaea, algae, bacteria, fungi, lichen and sometimes even animals and plants, and through different means, be it chemical or mechanical processes that affect the appearance and/or the integrity of the materials [2]. Among the several microorganisms responsible for biodeterioration, fungi are of particular note due to their ubiquitous nature, ability to grow even in environments not suitable for life, such as those with low water activity values (a\({}_{\text{w}}\)), and complexity and variety of metabolic pathways. The latter allows them to break down not only organic matter but also hard-to-degrade biopolymers and produce organic and inorganic metabolites, such as organic acids and chelating agents, which can lead to chemical transformations of the substrate they inhabit [3]. All these characteristics allow fungi to colonize and, by consequence of their biological activity, deteriorate paintings, stone monuments, books, parchments, leather and other materials that compose historically relevant objects [4]. It is important to note that there is a close relationship between materials and colonizing organisms, with colonization being heavily dependent on the chemical and mineralogical composition of the substrate as well as environmental conditions [5; 6; 7]. And while fungi play a multifaceted role in deterioration, with filamentous fungi, alongside lichens, sometimes playing a protective role against environmental parameters [8; 9], more often than not, that role is a deteriorative one. Fungal growth in cultural heritage artworks affects the object in distinct but often concurrent ways, leading to aesthetic, physical and/or chemical alterations of the artifact. Physical processes such as hyphal apical growth or fruiting body formation on the surface and/or on the interior of the colonized material result in significant aesthetic alterations, such as darkening and discoloration [7; 9], changing the original appearance of the piece, as well as compromising its integrity if the colonization happens at an inner layer level, with mycelial growth potentially causing exfoliation (detachment of painted layers) in paintings and similar artworks [7]. These processes can also promote the deterioration of stone monuments and similar artifacts by hyphal penetration and lead to phenomena such as biopitting, particularly present in monuments and artifacts colonized by highly melanized fungi, as melanin enhances the strength of the cell wall and facilitates invasion of the inner stone layers [4; 10; 11]. Simultaneously, chemical damage can happen as a consequence of fungal metabolism, both by digestion of the substrate and excretion of metabolites to the contaminated area. Excretion of enzymes such as cellulases and proteases can lead to the deterioration of artifacts such as books, parchments and even cinematographic films [12; 13], while the produced metabolites can cause mass loss through material dissolution and formation of soluble or insoluble salts [14]. In museum environments, fungi belonging to the _Alternaria_, _Aspergillus_, _Cladosporium_ (in particular _C. cladosporioides_) and _Penicillium_ genera, among others, are the most common [4].