Evaluating the Antifungal Activity of Volatilized Essential Oils on Fungi Contaminating Artifacts from a Museum Collection

As is the case for all forms of cultural heritage, museum collections are under a serious threat of biodeterioration, with fungi playing a significant role in this phenomenon, compromising the preservation and dissemination of past knowledge, artifacts and traditions. As part of the ongoing efforts to study the fungal contaminations observed in the artifacts that compose the collection of the Science Museum of the University of Coimbra, non-invasive sampling of four objects present in the archive was conducted and 43 fungal isolates were retrieved. These isolates were subjected to a comprehensive analysis based on molecular and morphological characteristics and were identified as belonging to 15 different species. Of the 15 isolated species, 5 were selected for in vitro antifungal essential oil assays, based on their relative abundance and biodeteriorative potential. For these, essential oils of Cymbopogon citratus, Lavandula angustifolia, Thapsia gummifera, Mentha pulegium, Mentha suaveolens, Thapsia villosa, Thymus mastichina and Agastache foeniculum were obtained via hydrodistillation, in accordance with the European Pharmacopeia. Of the tested oils, most impacted fungal growth, with Cymbopogon citratus and Lavandula angustifolia being able to fully inhibit the growth of most fungi even at the lowest tested concentrations.