Fungal stains on paper: is what you see what you get?

Abstract

Mitigation of fungal biodeterioration on paper documents and artworks represents a challenge to conservators worldwide. Numerous lists of fungal species have been identified from paper collections, but are those species responsible for the respective biodeterioration phenomena or just environmental contaminants? The present work was aimed at obtaining an association between specific fungal stains and causative fungal species. 23 stains from three paper documents were sampled. Fungal structures observed in situ with optical and scanning electron microscopy were compared with the identification of isolates by molecular biology tools. Correlation between the observed fungal structures and the identified fungal isolates was achieved, varying from 13% to 64% of the samples within the three studied documents. Grey/black and dark brown stains were associated with Chaetomium globosum, C. murorum, Penicillium chrysogenum, P. commune, Myxotrichum deflexum and Stachybotrys chartarum. Eurotium rubrum was isolated from a foxing stain and Penicillium citrinum was identified on light orange stains. Resumo A mitigação da biodeterioração causada por fungos em obras de arte e documentos em papel representa um desafio para os conservadores em todo o mundo. Inúmeras listas de espécies fúngicas têm sido identificadas a partir de coleções em papel, mas serão estas espécies responsáveis pelos respetivos fenómenos de biodeterioração? O presente estudo teve como objetivo associar espécies de fungos específicas a manchas observadas em documentos e obras de arte em papel. Foram amostradas 23 manchas existentes em três obras em papel. A observação in situ das estruturas fúngicas, com recurso a microscópio ótico e microscópio eletrónico de varrimento, foi comparada com a identificação de isolados através de técnicas de biologia molecular. As manchas negras e de tom castanho-escuro foram associadas às espécies Chaetomium globosum, C. murorum, Penicillium chrysogenum, P. commune, Myxotrichum deflexum e Stachybotrys chartarum. A espécie Eurotium rubrum foi isolada de uma mancha de foxing e a espécie Penicillium citrinum foi identificada em manchas de tom laranja claro.

Preserving cultural heritage: Analyzing the antifungal potential of ionic liquids tested in paper restoration

“…For our study, we selected four fungal strains known to cause paper deterioration in archives, namely Chaetomium globosum, Penicillium chrysogenum, Penicillium glabrum and Aspergillus versicolor [8, 10, 11] plus one recently isolated wild type strain of the highly cellulolytic genus Trichoderma, T. capillare [32]. All of the five selected fungal strains were reported to have good cellulolytic capabilities [34-37], making them suitable for the evaluation of the antifungal potentials of ILs on paper-decomposing molds.…”

“…Exogenous abiotic factors, such as humidity and temperature for example, not only affect abiotic deterioration processes, but also facilitate microbial attack [7]. In a recent survey among 57 institutional participants from 20 different countries, Sequeira et al [8] have found that 79 % of the participants had to deal with fungal infestations even though common preventative measures against fungal deterioration had been undertaken. According to the authors, most of these infestations were caused by unforeseen water contact (floods, leakage, fire suppression, outdoor humidity) or failure of (micro-)climate control systems, illustrating the importance of this issue beyond (sub-)tropical areas [1].…”

Conservation intervention on an embroidery with beads on perforated cardboard: problems and solutions

“…Nesta intervenção mínima incluiu-se a limpeza superficial do bordado, a consolidação e preenchimento do papel perfurado de modo a reforçar a sua resistência colonização biológica não confirmou esta hipótese, pois, por um lado, só numa das oito amostras recolhidas para colonização biológica se observou microorganismos (fungos do género Aspergillus) e, por outro lado, o desenvolvimento desse fungo apenas numa zona marginal da caixa de Petri sugere que essa identificação, como acontece com alguma frequência [11], resultou de contaminação.…”

Preserving cultural heritage: Analyzing the antifungal potential of ionic liquids tested in paper restoration

“…In a recent survey among 57 institutional participants from 20 different countries, Sequeira et al . [8] have found that 79% of the participants had to deal with fungal infestations even though common preventative measures against fungal deterioration had been undertaken. According to the authors, most of these infestations were caused by unforeseen water contact (floods, leakage, fire suppression, outdoor humidity) or failure of (micro-)climate control systems, illustrating the importance of this issue beyond (sub-)tropical areas [1].…”

“…Extensive literature on deterioration-causing microorganisms, especially fungal isolates from libraries and archives, is available [6–11]. For example, Chaetomium globosum , Penicillium chrysogenum as well as other species of the respective genera were isolated from and identified as causative for dark stains in historic documents [8]. Species such as Aspergillus versicolor (among Aspergillus species) in addition to a diverse set of Trichoderma species were also reported to be ubiquitously found in archives, museums and libraries [10, 11].…”