Characterization of Fungal Melanins from Black Stains on Paper Artefacts

Melanins play a fundamental role in the biology and ecology of several fungal species. Unfortunately, this group amorphous macromolecules also severely (and most times irreversibly) stains cultural heritage objects. Despite efforts made throughout years, knowledge chemical composition structure melanins is still insufficient, which hampers task safely cleaning these colourants from materials targeted way without causing further deterioration. This work aimed therefore to contribute towards enlightening characteristics three fungi that are common paper colonizers: Aspergillus niger, Chaetomium globosum Cladosporium cladosporioides. The extracted were characterized by FTIR, Raman, UV-vis, Solid-State NMR MALDI-TOF MS spectroscopies effect inhibitors DHN-melanin DOPA-melanin pathways on colony pigmentation growth was evaluated. Although all show predominantly aromatic with carbonyl phenolic groups, some differences between can be highlighted. obtained Ch. Cl. cladosporioides exhibited similar structures both presented characteristics, while A. niger’s revealed more complex ordered structure, higher prevalence highly conjugated carbonyls than others, besides additional presence yellow/green component. These conclusions cannot overlooked selecting methodologies for melanin materials.