Fungal melanins that deteriorate paper cultural heritage: An overview.

Paper-based works of art and documents of cultural importance kept in museums and libraries can show notorious signs of deterioration, including foxing stains, caused by fungal colonization. Some of the main chromophore agents of fungal origin that deteriorate paper and therefore affect paper cultural heritage both aesthetically and structurally are the group of pigments called melanins. Thus, knowledge of the diversity and features of fungal melanins and of the melanization pathways of fungi growing on paper is key to removing these pigments from paper-based works of cultural importance. This review provides an approach about the current knowledge of melanins synthesized by paper-colonizing fungi, their localization in the fungal structures, and their role in the deterioration of paper. This knowledge might contribute to developing new, effective, and sustainable strategies of restoration and conservation of historical documents and works of art based on paper.

Fungal monitoring of the indoor air of the Museo de La Plata Herbarium, Argentina.

BACKGROUND: Biological agents, such as fungal spores in the air in places where scientific collections are stored, can attack and deteriorate them. AIMS: The aim of this study was to gather information on the indoor air quality of the Herbarium of Vascular Plants of the Museo de Ciencias Naturales de La Plata, Argentina, in relation to fungal propagules and inert particles. METHODS: This study was made using a volumetric system and two complementary sampling methods: (1) a non-viable method for direct evaluation, and (2) a viable method by culture for viable fungal propagules. RESULTS: The non-viable method led to ten spore morphotypes being found from related fungal sources. A total of 4401.88spores/m3 and 32135.18 inert suspended particles/m3 were recorded. The viable method led to the finding of nine fungal taxa as viable spores that mostly belonged to anamorphic forms of Ascomycota, although the pigmented yeast Rhodotorula F.C. Harrison (Basidiomycota) was also found. A total count of 40,500fungal CFU/m3 air was estimated for all the sites sampled. CONCLUSIONS: Both the non-viable and viable sampling methods were necessary to monitor the bio-aerosol load in the La Plata Herbarium. The indoor air of this institution seems to be reasonably adequate for the conservation of vascular plants due to the low indoor/outdoor index, low concentrations of air spores, and/or lack of indicators of moisture problems.