A cidade de Ouro Preto, Patrimônio Mundial, possui monumentos de grande importância cultural, como o Chafariz da Glória. Apesar da relevância da sua preservação, essas construções sofrem ...continuamente a deterioração provocada pela ação das intempéries e de agentes biológicos. Nomeadamente, os fungos são importantes biodeteriógenos devido à produção de enzimas e ácidos. Este trabalho tem como objetivo verificar a presença de fungos e identificá-los, buscando relacionar a sua colonização com as degradações visualizadas nas áreas mais deterioradas do Chafariz. Foram identificados os seguintes gêneros e espécies fúngicas: Aspergillus sp.; Fusarium sp.; Phialophora gregata; Scopulariopsis brevicaulis e Nigrospora sp. Sabendo- da ação deterioradora dos fungos, estudos que identifiquem os biodeteriógenos se tornam de grande importância, uma vez que possibilitam a adoção de medidas de controle direcionadas para tais agentes.
Display omitted
•Protection of stony materials against biodeterioration by ecofriendly compounds.•Electroprecipitation of borates of different solubility to increase their applicability.•The ...treatment allows the precipitation of different boron compounds.•The treatment is effective in preventing the fungal colonization.•The crystallization habit and penetrability differ depending on the material to be treated.
Biodeterioration is a serious threat to the preservation of cultural heritage. Currently, the chemical treatments used to combat it must fulfil a series of restrictions to ensure that they are not harmful to humans or the environment. Borates satisfy these conditions but due to its high degree of leaching its application is limited to indoor areas. The use of electroprecipitation may to increase the range of applicability by allowing to precipitate, along the entire section of the stony materials, of a mixture of boron salts with different solubility (zinc, magnesium, and sodium borates) to cover a wide range of moisture conditions. The results obtained show that electroprecipitation not only increases the penetration depth of boron compounds but also allows the formation of compounds of different solubility, which allows the treatment to last over time. Furthermore, the treatment increased the mechanical properties and reduced the porosity of the stones treated, all without causing significant aesthetic changes.
•The alcobaça monastery currently exhibits an extensive bacterial pink biofilms.•This biodeterioration evidence seems to be associated with salt efflorescences.•The colour is probably due to the ...production of bacterial pigments.•High-throughput sequencing allowed the identification of pink-pigmented bacteria.•This study is helpful to determine the best cleaning procedure to be implemented.
The Alcobaça Monastery (Portugal), a UNESCO World Heritage Site, currently exhibits a high degree of surface alterations of the stone architectural elements inside the church, including an extensive pink coloration in the walls and columns, bacteria biofilms, and salt efflorescences. The main goal was to identify the microbiota that colonizes the walls and columns of this monument, to help custodians and conservators-restorers in the selection of the correct procedure to be adopted for the conservation of the monument. Regarding the observed pink discoloration, and considering previous studies, we hypothesize that is caused by biofilms formed by bacteria or other microorganisms that produce pigments of the same color, particularly carotenoids. Curiously, a distinct phenomenon was noticed: the pink discoloration always seems to appear at a very similar height in most of the columns and walls, starting at 40 cm to the floor and associated with the presence of salts on the walls. Using high-throughput sequencing approaches, we were able to characterize the microbial community present. We identified several bacteria that are producers of pink pigments and halotolerant such as Rubrobacter radiotolerans, Domibacillus robiginosus, Bacillus licheniformis and Halalkalicoccus sp. that develop in areas of high salinity.
Cultural heritage plays a key role in understanding the history of humankind; therefore, the adoption of appropriate strategies for its conservation is essential. Microorganisms, such as bacteria, ...fungi and microalgae, which are usually organized on the surface in microbial communities as “biofilms”, can cause serious problems in the conservation of cultural heritage, making the adoption of prevention and conservation strategies a critical issue. This editorial focuses on studies published within the present Special Issue that present advances in the field of the biodeterioration of cultural heritage caused by microbial communities, with a particular focus on new methods for their elimination and control.
Biological growth represents one of the main threats for the conservation of subterranean cultural heritage. Knowledge of the conditions which favour the various taxonomic groups is important in ...delineating their control methods. Combining our experience regarding hypogea in Italy and the Republic of Korea, we aim to perform a critical review and comparison of the Biodeterioration Patterns (BPs) found, the materials used, and the conservative treatments applied. For this purpose, we focused on Etruscan tombs (Italy, 7th to 3th century BC) and the ancient tombs of the Baekje Dynasty (Republic of Korea, 6th to 7th centuries AD), most of which have been designated UNESCO World Heritage Sites, collecting original and bibliographic data as well as official documents. Results highlight the rich biodiversity of the bacterial and fungal species. Phototrophs were observed only in niches with sufficient light and the development of roots was also detected. Changes in humidity and temperature, the nature of the soil, nutrient accumulation, and vegetation above the hypogea along with human activities explain the different BPs. The effects of biocide treatments are also discussed, such as the emergence of dangerous fungal species. The shared data also enhance the role of overlaying tumuli and vegetation as well as protective barriers to reduce biological risk.
The purpose of this study was to evaluate the natural durability of Cupressus lusitanica, Cryptomeria japonica and Pinus taeda woods subjected to a rotting field trial, through mass loss and ...deterioration index. The trial was conducted in an open field in the city of Curitibanos, State of Santa Catarina, Brazil, for a 24-month period, with evaluations carried out every 6 months. For developing the study, we used the woods of Cupressus lusitanica (16 years), Cryptomeria japonica (16 years) and Pinus taeda (juvenile=15 years and mature wood>30 years) species, from which test specimens were made with the dimensions of 2.5 x 5.0 x 50.0 cm in thickness, width and length, respectively, following the standards suggested by IUFRO. After 24 months of exposure to the rotting field the woods of C. japonica and C. lusitanica species showed a deterioration index that reflected an evident but moderate attack of fungi and termites, while the woods of P. taeda (juvenile) and P. taeda (mature) showed deterioration index that reflected an intense rotting and intense attack of termites. Regarding the mass loss the woods of C. japonica and C. lusitanica were classified as highly resistant, while P. taeda (juvenile) was considered resistant and P. taeda (mature) was considered moderately resistant. In general, the woods of C. lusitanica and C. japonica showed greater natural durability when used in contact with the soil.
Fungi play a considerable role for the deterioration of cultural heritage. Due to their enormous enzymatic activity and their ability to grow at low
a
w
values fungi are able to inhabit and to decay ...paintings, textiles, paper, parchment, leather, oil, casein, glue and other materials used for historical art objects. The weathering of stone monuments is significantly increased by epi- and endolitic fungi. In museums and their storage rooms, climate control, regular cleaning and microbiological monitoring are essential in order to prevent fungal contamination. Education and close collaboration of mycologists and restorers are needed to develop object specific methods for the conservation and treatment of contaminated objects.
2020 marks 25 years since Olivier Guillitte defined the term ‘bioreceptivity’, to describe the ability of a building material to be colonised by living organisms. Although Guillitte noted in his 1995 ...paper that several issues required further investigation, to the best of our knowledge the bioreceptivity concept has not been restated, reviewed, reanalysed or updated since then. The present paper provides an opinionated exposition of the status and utility of the bioreceptivity concept for built heritage science and conservation in the light of current knowledge, aimed to stimulate further discussion. A bibliometric analysis highlights the key dimensions of the past 25 years of published research, showing that the term bioreceptivity has been widely used in the field of built cultural heritage. In our reanalysis of the concept, special attention is devoted to the six types of bioreceptivity (primary, secondary, tertiary, intrinsic, extrinsic and semi-extrinsic) articulated by Guillitte in 1995. We propose that field-based studies of bioreceptivity are urgently needed, and that the intrinsic, extrinsic and semi-extrinsic types of bioreceptivity should be dropped, and a new category (quaternary bioreceptivity) added. Additionally, we propose that bioreceptivity in submerged and subsoil environments should also be considered. Bioreceptivity remains an important concept for managing both new build and built heritage, as it provides the key to understanding the drivers and patterns of biological colonisation of building materials.
The Jāmé Mosque of Isfahan or Masjed-e Jāmé is a historical mosque listed as a World Heritage Site by UNESCO in 2012. Tiles are one of the main materials used in this monument. This study was ...designed to assay the growth of fungi on the glazed tile and evaluating their alterations in the laboratory. Three fungi, Aspergillus niger and Parengyodontium album from outdoor of monument and Penicillium polonicum from indoor of monument, which were previously isolated, selected for this study. The axenic and mixed culture of the fungi was inoculated on glazed tiles (2.5 × 2.5 cm) with different colors of Mosaic, Anthracite blue and Soft fauna and incubated for 6 months at 28–30 °C. After six months incubation, the biodeterioration patterns were assessed via stereomicroscopy, scanning electron microscopy and colorimetry. The results showed that fungi have the ability to attach, grow and form crystals over the glazed tile surfaces. It seems that the growth pattern was affected by fungal species and color of tile. Modeling experiments can be used to evaluate fungal deterioration and to help prediction of appropriate time of restoration.
Display omitted
•The bioreceptivity and biodeterioration of Isfahan Masjed-e Jāmé glazed tiles was studied.•Glazed tile models with three different colors were tested.•Six-month laboratory colonization experiment was performed with the tiles inoculated by three fungi and mixed of them.•Biogenic minerals were observed due to fungal growth.•Bioreceptivity and biodeterioration was depended on tile color and fungal strain.
PDF
