In this study, we explored the biodiversity and abundance of culturable fungi in four samples associated with different biodeterioration outlines collected from the Lemos Pantheon, a limestone-built artwork in Portugal. We compared the results from prolonged standard freezing with those previously obtained from fresh samples to analyze differences in the obtained community and assess the effectiveness of the standard freezing incubation protocol in uncovering a different segment of culturable fungal diversity. Our results showed a slight decrease in culturable diversity, but over 70% of the obtained isolates were not present in the previously studied fresh samples. We also identified a high number of potential new species with this procedure. Moreover, the use of a wide variety of selective culture media positively influenced the diversity of the cultivable fungi obtained in this study. These findings highlight the importance of developing new protocols under varying conditions to accurately characterize the culturable fraction in a given sample. The identification and study of these communities and their possible contribution to the biodeterioration process is crucial knowledge for formulating effective conservation and restoration plans to prevent further damage to valuable cultural heritage assets.

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.

Fungal organisms play a major role in the contamination and biodeterioration of natural history museum collections and cultural heritage as a whole, leading to the potential loss of key knowledge preserved by these. As part of the ongoing efforts to study the fungal contaminations observed in the Science Museum of the University of Coimbra (Portugal) collections, eight taxidermized birds were sampled and 27 fungal isolates were retrieved. A comprehensive analysis of these isolates led to the identification of 14 different species belonging to 13 different genera, with Aspergillus accounting for 37% (1 species), Talaromyces for 11.11% (1 species); Cladosporium, Paramicrodochium, and Periconia accounting for 7.4% each (2, 1, and 1 species, respectively); and Arcopilus, Beauveria, Coprinellus, Hyphodermella, Mycoaciella, Neokalmusia, Paraeutypella, and Penicillium collectively accounting for 3.7% each, all represented by a single species. Among these were two isolates of an unknown Periconia species. These isolates were thoroughly studied through an integrative analysis based on a multi-locus phylogeny of a combined dataset of ITS rDNA, LSU, SSU, TEF1α, and RPB2, along with morphological characteristics. Based on the data obtained from this study, we propose a new addition to this genus, Periconia callaina sp. nov. This discovery provides further insight into the fungal diversity present in natural history museums and the communities that colonize and threaten our cultural heritage.

Background/Objectives: Fungal keratitis (FK) is a current challenge in ophthalmology, due to its association with severe visual impairment and limitations of current antifungal therapies. We aim to evaluate the antifungal activity of essential oils (EOs) from aromatic and medicinal plants Cymbopogon citratus and Lavandula pedunculata against selected FK pathogens collected from FK patients in two Portuguese hospitals. Methods: The antifungal activity of EOs was tested at concentration of 25%, 50%, 75%, and 100%, up to 7 days, through solid-phase disk diffusion testing in vitro assay. Results: Candida albicans were the more prevalent (28.6%), followed by Candida parapsilosis (21.4%) and Dicyma olivacea (14.2%). Other species identified were Aspergillus fumigatus and Scedosporium boydii (7.1%). Clinical diagnostic methodologies showed agreement with the molecular identification (data not shown). Cymbopogon citratus EO showed higher antifungal activity than Lavandula pedunculata EO. Highest antifungal activity was observed against Aspergillus fumigatus and Scedosporium boydii (inhibition zone diameter, IZD=90.0mm), up to 7 (Cymbopogon citratus EO) or 3 days of incubation (Lavandula pedunculata EO). While the antifungal activity of Cymbopogon citratus EO was maintained during the study (for Aspergillus fumigatus, Candida albicans and Scedosporium boydii), it decreases with time with Lavandula pedunculata EO. Conclusions: Cymbopogon citratus EO and Lavandula pedunculata EO showed optimal antifungal activity against molds (Aspergillus fumigatus and Scedosporium boydii), up to 3 days of incubation. Against yeasts (Candida albicans and Candida parapsilosis), the EOs showed lower activity. Our study shed light on developing new pharmacological strategies for FK based on EOs extracted from aromatic and medicinal plants.

Background/Objectives: Fungal keratitis (FK) is a current challenge in ophthalmology due to its association with severe visual impairment and the limitations of current antifungal therapies. We aim to evaluate the antifungal activity of essential oils (EOs) from the aromatic and medicinal plants Cymbopogon citratus and Lavandula pedunculata against selected FK pathogens collected from FK patients in two Portuguese hospitals. Methods: The antifungal activity of the EOs was tested at concentrations of 25%, 50%, 75%, and 100% for up to 7 days using the solid-phase disk diffusion in vitro assay. Results: Candida albicans was the most prevalent pathogen (28.6%), followed by Candida parapsilosis (21.4%) and Dicyma olivacea (14.2%). The other identified species were Aspergillus fumigatus and Scedosporium boydii (7.1%). Clinical diagnostic methodologies showed agreement with the molecular identification. Cymbopogon citratus EO showed higher antifungal activity than Lavandula pedunculata EO. The highest antifungal activity was observed against Aspergillus fumigatus and Scedosporium boydii (inhibition zone diameter, IZD = 90.0 mm) after 7 (Cymbopogon citratus EO) or 3 days of incubation (Lavandula pedunculata EO). While the antifungal activity of Cymbopogon citratus EO was maintained during the study (for Aspergillus fumigatus, Candida albicans, and Scedosporium boydii), the antifungal activity of Lavandula pedunculata EO decreased with time. Conclusions: Cymbopogon citratus EO and Lavandula pedunculata EO showed optimal antifungal activity against molds (Aspergillus fumigatus and Scedosporium boydii) after 3 days of incubation. Against yeasts (Candida albicans and Candida parapsilosis), the EOs showed lower activity. Our study sheds light on the development of new pharmacological strategies for FK based on EOs extracted from aromatic and medicinal plants.