Molds in museum environments: Biodeterioration of art photographs and wooden sculptures

Arch. Biol. Sci., Belgrade, 65 (3), 955-962, 2013 DOI:10.2298/ABS1303955G MOLDS IN MUSEUM ENVIRONMENTS: BIODETERIORATION OF ART PHOTOGRAPHS AND WOODEN SCULPTURES MILICA LJALJEVIĆ GRBIĆ*1, M. STUPAR1, JELENA VUKOJEVIĆ1, IVANA MARIČIĆ2 and NATAŠA BUNGUR1 1 University of Belgrade, Faculty of Biology, Institute of Botany and Botanical Garden “Jevremovac”, 11000 Belgrade, Serbia 2 Museum of Contemporary Art, Ušće 10, Blok 15, 11070 Novi Beograd, Belgrade, Serbia Abstract - Pieces of art stored in museum depots and display rooms are subject to fungal colonization that leads to biodeterioration processes. Deteriorated wooden sculptures and art photographs temporarily stored in the quarantine room of the Cultural Center of Belgrade were subject to mycological analyses. Twelve fungal species were identified on the wooden substratum and five species were detected on photograph surfaces. Trichoderma viride, Chaetomium globosum and Alternaria sp. were the fungi with proven cellulolytic activity detected on the examined cellulose substrata. Indoor air mycobiota were estimated to 210.09 ± 8.06 CFU m-3, and the conidia of fungus Aspergillus niger were the dominant fungal propagules in the air of the examined room. Key words: art objects, biodeterioration, cellulose substrata, fungi, indoor air, museum environment. INTRODUCTION the indoor air. The dominant fungal structures in indoor air are the conidia of mitosporic fungi (Florian, 2002). Fungi can be introduced into an indoor environment such as museum depots through transport by workers and visitors via their bodies, clothes and carried items or with outdoor air through ‘‘natural gates’’ such as doors and windows (Niesler et al., 2010). Incorrectly operating air-conditioning system may also be a source of fungal propagules (Ljaljević Grbić et al., 2008). The presence of fungal propagules in indoor air causes adverse health effects, especially allergies and asthma (Bush and Portnoy, 2001). When fungal propagules in an indoor environment settle on different surface conidia germination and mycelia formation can occur. The key factors that determine the germination and growth of fungi are the chemical and structural composition and water activity of the substratum and prevailing environmental factors of temperature, gas composition, pH and The fungal colonization of pieces of art presented in display rooms of museums, galleries or stored in depots is nowadays a significant problem for cultural heritage conservators (Sterflinger, 2010). Pieces of art are made of all types of organic and inorganic materials. It is well known that fungi are capable of colonizing, altering and degrading all kinds of materials, and pieces of art are no exception. There are many reports concerning the fungal deterioration of art objects such as paintings (Vukojević and Ljaljević Grbić, 2011), stone monuments and masonry (Ljaljević Grbić et al., 2010), wooden sculptures (Fazio et al., 2011), paper and parchment materials (Cappiteli and Sorlini, 2005), cinematographic films (Abrusci et al., 2005), textiles (Szostak-Kotowa, 2004) etc. Viable fungi isolated from pieces of art presented in an indoor environment in most cases come from 955 956 MILICA LJALJEVIĆ GRBIĆ ET AL. Fig. 1. Sampling objects for mycological analyses. A. “Educational sculpture” by Marko Crnobrnja, B. Art photograph from collection “Earth” by Aleksandar Rafajlović. light (Saiz-Jimenez, 1993). A fungal infestation on a piece of art contains fungal structures and metabolic products, such as enzymes, citric acid cycle products, secondary metabolites, pigments, odors, etc. Materials colonized by fungi usually undergo changes in their chemical and physical characteristics (Florian, 2002). Fungal infestation on pieces of art leads to biodeterioration and must not be neglected due to the increasing aesthetic value of art objects as well as the impact on health of conservators. MATERIALS AND METHODS Case report The collection consisted of deteriorated art photographs (Fig. 1B), 24 pieces of two artworks “Sky” and “Earth” made by the eminent photographer Aleksandar Rafajlović (part of the collection of the Museum of Contemporary Art in Belgrade), wooden sculptures (Fig. 1A) made by the artist Marko Crnobrnja as well as different textile and terracotta artworks. The deteriorated wooden sculptures and photographs were subjected to mycological analyses. The artworks were sent to Istanbul (Turkey) for an exhibition, “Belgrade’s experience: The October Salon”, as reputable pieces of contemporary art in Serbia. During the process of preparing the exhibition Istanbul was devastated by a flood and seawater seriously impaired the condition of the photographs and sculptures and they lost their artistic value. The sampling took place in a quarantine room of the Cultural Center of Belgrade (CCB) where the deteriorated art objects were temporarily stored. Sampling of aeromycobiota Sampling of aeromycobiota was carried out in a temporary quarantine room of the CCB by the passive sedimentation method described by Omeliansky (1940). Petri dishes containing malt extract agar (MEA) were placed open at approximately 2 m above the floor and were exposed for 30 min. The antibiotic streptomycin was added during the preparation of the medium in order to suppress bacterial growth. After 7 days of cultivation at 25˚C the fungal colo- MOLDS IN MUSEUM ENVIRONMENTS 957 nies were counted. The CFU (colony-forming unit) number per cubic meter of air (CFU m-3) was estimated according to Omelyansky’s formula: N=5a x 104(bt)-1 where N is fungal CFU m-3, a is the number of fungal colonies per Petri dish, b is the Petri dish surface (cm2), t is the exposure time (min). Relative fungal distribution was conducted according to Smith (1980) i.e. the number of colonies of genera or species/total number of colonies of all genera or species x 100. Sampling of surface mycobiota According to the surfaces, the examined samples were classified as photographic paper and wooden samples. Sampling was performed from 2 cm2 of each photograph and each wooden sculpture with sterile cotton swabs. Isolation and identification of fungi The swabs were immersed and homogenized in a sterile physiological solution and serial dilutions were made. Each dilution was inoculated (0.1 ml) on MEA with streptomycin added. After 7 days of cultivation at 25˚C, identification of the fungi was performed. Cultural and micromorphological characteristics of fungal colonies were observed and identification was performed using identification keys (Ainsworth et al., 1973; Arx, 1974; Ellis and Ellis, 1997; Pitt, 1979; Raper, and Fennel 1965; Samson et al., 2004). RESULTS The fungal concentration of air in the quarantine room of the CCB was estimated at 210.09 ± 8.06 CFU m-3. The prevailing fungal species documented in the air was Aspergillus niger Tiegh (62.5%), followed by Neurospora crassa Shear & B.O. Dodge (25%) and Trichoderma viride Pers. (12.5%) (Fig 2). T (...truncated)