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Gamma radiation is an effective technique for the conservation of art collections, reducing microbial loads and can be obtained by the emission of a radioactive isotope, such as Cesium 137. A Portinari's artwork (National Museum, Brazil) was analysed, and the fungi contained therein were isolated and treated with gamma radiation for decontamination. Radiation doses used were 16, 19 and 22kGy. Results indicated 11 genera and 17 species of fungi isolated. Penicillium and Cladosporium were isolated from air, the artwork, and its support. The genera Penicillium, Cladosporium, Nigrospora and Curvularia showed high resistance to radiation (16kGy) being the most resistant species Cladosporium, with no growth just under 22kGy. The results outlined indicate that the rates of DNA damage and repair were critical, depending on chronic or acute doses. The biochemical mechanism acting on fungal cells under irradiation was basically the inactivation of specific enzymes and, probably, DNA damage, particularly stimulating double-strand breaks. [ABSTRACT FROM AUTHOR]

Cultural heritage sites often experience the unfavorable alteration of biodeterioration of mural paintings and wall inscriptions. Controlling or preventing biodegradation that may occur has been achieved through the use of various treatment methods, such as physical, chemical, and environmental control procedures. Regrettably, these treatments are often highly toxic to the health of conservators and visitors. Moreover, it causes pigmentation, is expensive, has low long-term results, and has poor long-term effectiveness. The use of Ag@ZnO core shell prototype in the field of cultural heritage was the first time in this research. The application was made to a painted wall inscription that dates back to the Middle Kingdom of ancient Egypt. A one-step chemical method was used to synthesize Ag@ZnO and it was examined using XRD, TEM, BET surface area, and Raman. These tests proved that the silver's core shell covered the zinc oxide's core and confirmed its purity. The painting on the wall was analyzed by SEN-EDX, Raman, and XRD analysis, and it was determined that the stone was limestone, the pigments were (Carbon for black pigment, Hematite for a red pigment, and Egyptian blue for blue pigment). These pigments and animal glue were combined to create the binding medium. The painted wall inscription was treated with Ag@ZnO treatments using a spray technique with a 5% concentration. The spectrophotometer was used to confirm that the color change has been below 5. This treatment method is non-hazardous, can be utilized both in vivo and in vitro, and does not necessitate the required environmental atmosphere or UV index. [ABSTRACT FROM AUTHOR]

Biological colonization and later biodeterioration damage are well-known phenomena affecting cultural heritage. Glasses, as those from historical stained glass windows, are frequently biocolonized under certain conditions. There is still limited knowledge about biocolonization growth patterns on glass and safe removing procedures to act before irreversible biodegradation damage occurs. This paper presents the results of an experimental study in which biological colonization of three different model historical glasses, namely sodalime, lead crystal, and potash-lime silicate glasses, has been naturally induced. Glass samples were exposed for 13-15 months to natural conditions at the mountain region near Madrid (Spain) and monitored over time. After exposition, samples were first observed through fluorescence microscopy (FM), scanning electron microscopy (SEM), and UV-Vis-NIR spectrophotometry. Next, the Acticide® CF biocide was applied on glass samples exposed and were then again observed through the same techniques to evaluate its effect. Biocolonizers detected were algae, fungi, cyanobacteria and heterotrophic bacteria in different combinations and amounts and sometimes forming a biofilm. Soda-lime silicate glasses were the ones that showed the highest biocolonization growth, while lead crystal silicate glass appeared more biocolonized than the potash-lime one. The biofilm formed appeared intensely damaged and was practically no longer visible after the biocide treatment which proves its efficiency for removing glass biocolonization. [ABSTRACT FROM AUTHOR]

Biodeterioration of cultural property is a major problem in almost all parts of the world. This paper focuses on the major biodeteriogens, the relative effects of the errant and uncontrollable environmental conditions, and the threat, vulnerability, and risk cause due to biodeterioration to the skin and skin-products most commonly found in the museum collections. The present paper was aimed to assess the investigation of three indigenous medicinal plants for their toxic and insecticidal activity against the Anthrenus verbasci, the stored product, and skin and skin-product pests. It also demonstrated a comparative study between the toxicities of three essential oils such as Ferula asafoetida, Syzygium aromaticum, and Mentha x piperita as fumigants against the larvae of Anthrenus verbasci after the 7 days of exposure under laboratory conditions (23°C ± 5 °C and 58% ± 6%RH). Probit analysis was done by SPSS software and then the transformed data were used to draw regression line graphs for determining LC90 values in each case of tests. The futuristic aspect of this study is to identify the active molecules from promising plant sources and evaluate them for application at the commercial level to develop environmentally friendly and human safe biopesticides with high efficiency and recyclability. [ABSTRACT FROM AUTHOR]

This paper describes the effect of various iron-gall inks on acid and alkaline papers and their relation to biodeterioration. Different types of papers were used in the present study, where several tests were performed: spot-tests for lignin and starch detection, chemical digestion to quantify total iron content, desorption studies to remove iron from the papers, followed by accelerated artificial aging, scanning electron microscopic studies and biodeterioration tests. Results indicated that lignin was only detected on acid papers, while starch was detected both on acid and alkaline papers. Treatment with calcium phytate proved to be an efficient process to remove excess iron from the inks. Scanning electron microscopic images showed distinct surface spreading of inks on the papers, depending on the iron content. Finally, in the absence of any other carbon source, papers strips containing iron-gall inks proved to be amenable to biodeterioration, indicating that chemical and biochemical deterioration simultaneously occur. [ABSTRACT FROM AUTHOR]

Fungi play a very important role in deterioration of ancient wood antiques and therefore must not be neglected due to the increasing aesthetic value of art objects as well as the impact on health of conservators. A number of chemicals have been used for the treatment of museum artefacts. Biocides are the most effective at eradicating spores and mature organisms. Dimethyl sulfoxide (DMSO) is frequently used as a solvent for anti-fungal drugs. This study was carried out to evaluate in vitro and in vivo antifungal efficacy of DMSO against Aspergillus parasiticus. In vitro, fifty percent of DMSO gave complete inhibition of the growth. Also, 25% of DMSO inhibition growth by 60%. On the other hand low concentrations of DMSO were less effective. In vivo studies, treatment with DMSO on biodeteriorated sycamore wood resulted in inhibition of fungal growth. Furthermore, the application of DMSO had no effect on the colour, structure and chemical characteristic of the wood as well as, DMSO removed extraneous wood components that easily dissolve in DMSO. [ABSTRACT FROM AUTHOR]

This paper describes the deterioration and preservation of an Ancient Egyptian polychrome wooden coffin, dating back to the 1st century. Common deterioration problems are the wood splitting and cracking, detachment of ground and paint layers, fungal damage, dirt adhesion and staining. The project entails securing the severely damaged wood, preparation of lime layer, the painting layer, and paint layer to a substrate, by consolidation, cleaning, dust removal and treatment of the degraded wood. Qualitative analysis of samples selected from the coffin, was reported. Studies that includes the identification of wood species, ground layer, paint layer, binding medium and microbiological identification were made. Several analytical methods were employed in the identification processes such as the Light optical microscopy (LOM), Scanning electron microscopy equipped with energy dispersive X-ray analyzer (SEM-EDS), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The obtained data were used to evaluate the deterioration status of the coffin and to establish suitable treatment methods.

Thirteen species of fungi were obtained out of ten samples (five samples of each monument) collected from various places of stone structures of the monuments. Aspergillus fumigatus Fr.species are found in all samples and their percentage frequency is very high. Aspergillus fumigatus Fr., Aspergillus terreus Thom. And Aspergillus flavus fungal species are common on stone of the monument. There should be given priority to the characteristic features of stone structures, their different forms, designs and materials in finding the cause(s) of their degradation and deterioration) This study infers that in the degradation and deterioration of stone there is equal contribution by microbes and the design of stone structures. Hence the nature of the substrate, the relation between substrate and organism, the relation between the design and growth of organism, their frequency distribution are essential components in stone monument preservation interventions.

Microcolonial black fungi have their natural ecological niche on rocks and walls of hypogean environments, playing an important role in the deterioration of materials and aesthetical alteration of monumental stones and mortars. Three black fungi (Sarcinomyces sp., Pithomyces sp. and Scolecobasidium sp.) have been isolated from cultural assets of historical interest. These fungal strains have been used to test the microwave heating method as a new control methodology for eradicating the fungal biological growth on cultural stone artifacts. This methodology is based on a 2.45 GHz microwave electromagnetic radiation, generated by a new apparatus with an appropriate applicator. The first results showed the best dose of 65°C for three minutes, for all the investigated fungal strains. This methodology is very promising because is safety for the operator and the environment, and can be easily applied on site. The use of this method to kill biodeteriogens can avoid the application of chemicals formulates potentially dangerous for substrates and environment.

Chhattisgarh is a land of ancient culture, with many ancient monuments, temples and forts. Every nook and corner of Chhattisgarh has traditional heritage. There are numerous factors that affect the durability of stone. Stone surfaces are continuously exposed to physical, chemical and biological degradation. Physical, chemical, and biological agents act in co-association, ranging from synergistic to antagonistic and leading to deterioration. Among biological agents, micro-organisms are of critical importance in stone deterioration. They can cause various damages on the stone surface. Biodeterioration processes result from complex interactions of surface-invading microbes with each other, as well as with the surface material. The ability of fungi to produce pigments and organic acids is crucial for the discoloration and degradation of monuments. Air acts as a vehicle for the dispersion of microorganisms. They are introduced into air from different sources: soil, water, organic waste, plant leaves, sneezes and cough. This investigation focuses on the scientific conservation of The Sita Devi Temple of Deorbija DistricDurg, [Chhattisgarh]. The stone surface of the temple grew dark due to deposits of dust, dirt, dried vegetation and the growth of micro vegetation on the exterior as well as the interior portions.

Five natural antibiofoulants with terrestrial (capsaicine - CS, cinnamaldehyde - CI) and marine origin (zosteric acid - ZA, poly-alkylpyridinium salts - pAPS and Ceramium botryocarpum extract - CBE) have been selected and tested against phototrophic biofilm formation on the stone surfaces for their inhibitory properties. The antibiofouling agents (ABAs) were incorporated into two commercial silicone based coatings (Silres BS OH 100 - S and Silres BS 290 - W). In this work, phototrophic growth was evaluated by epifluorescence microscopy and semi-quantitative image analysis. The results showed an inhibitory efficiency for almost all tested ABAs. However, this efficiency has been found for short time or when the incorporating agent were incompletely cured. Among the ABAs tested, the poly-alkylpyridinium salts and cinnamaldehyde incorporated into Silres BS 290 showed the best inhibitory efficiency.

The aim of this study was to evaluate the biocidal activity of essential oils of Syzygium aromaticum (L.) Merr. and L. M. Perry (nail) and Allium sativum L. (garlic) against different fungal species producing paper biodeterioration. Essential oils (EOs) were obtained from harvested plants in their natural habitat in Cuba, and were tested against the species Aspergillus niger, Aspergillus flavus and Penicillium sp. which were isolated from archival indoor environments and documents with patrimonial value The biocidal activity was studied at different concentrations (70, 50, 25, 12.5 and 7.5%) using the agar diffusion method. The effect of extracts on paper alterations was studied through different techniques including determination of pH and number of copper and scanning electron microscopy (SEM) observations. EOs were analyzed by gas chromatography coupled to mass spectroscopy (GC/MS). The determination of inhibition zones by the agar diffusion method of the tested EOs showed a moderate and/or positive effect. The study of the antifungal activity on paper ("in vivo") shows that both clove and garlic oils were potent biocides. Although the paper structure was not affected by EOs pure, some molecular damages were observed at lower concentrations across determinations of the pH and copper number. [ABSTRACT FROM AUTHOR]

One of the most important point for the restoration and protection of cultural heritage objects is the early identification of material deterioration caused by microbial colonization. Biodegradation has to be understood as a result of the activity of an entire microbial community, rather than that of individual members of such community. Fungi are among the most degradative organisms inducing biodeterioration processes of ancient and modern materials. Electrophoresis in denaturing gradient gel (DGGE) is the technique most often used to study the structure of the microbial communities colonizing artworks like painted art objects, mural paintings, historical window glass, historical limestone buildings and the like. The present article describes the usage of this method to analyze the diversity of fungal taxons on the sixteenth century textile material. Additionally the procedure of main taxon identification by sequencing was described. [ABSTRACT FROM AUTHOR]

Honeycomb weathering is a common surface phenomenon affecting a variety of rocks in a range of environments. The processes involve the appearance of closely spaced cavities which are generally small, with an average width of a few millimeters to several centimeters in diameter. Honeycomb weathering is also known as fretting, cavernous weathering, alveoli/alveolar weathering, stone lattice, stone lace or miniature tafoni weathering. Incipient honeycomb weathering in a homogeneous limestone has been experimentally reproduced by wind exposure and salt crystallization. It is a type of salt weathering common on coastal and semi-arid limestone. Honeycomb weathering occurs in many populated region and must have been noted in archaeological sites at Leptis Magna (Libya). Leptis Magna is a World Heritage site on the Mediterranean coast of North Africa in the Tripolitania region of Libya. In order to create an appropriated conservation concept, it was necessary to investigate the damage processes. For this purpose we used X-ray powder diffraction (XRD), optical and scanning electron microscope (SEM) coupled with EDX, Stereo microscope, polarizing microscopes (PM). Biodeterioration problems in the site were analyzed by taking into account their impact on the substrate and their relationship with environmental factors. Chemical analysis and field observations indicated that honeycomb weathering in coastal exposures of limestone in the archaeological sites of Leptis Magna resulted from the evaporation of salt water deposited by waves from the Mediterranean Sea. Microscopic examination of weathered samples showed that erosion resuled from the disaggregation of mineral grains, rather than from chemical decomposition. Thin walls separating adjacent cavities seem to be the result of the protective effects of organic coatings produced by microscopic algae inhabiting the rock surface. [ABSTRACT FROM AUTHOR]

Biodegradation and biodeterioration of mural paintings by microorganisms is an important research field that needs novel approaches to fully understand the mechanisms and effects. In this work, the presence of microorganisms and their biological activity were investigated by extra and intracellular enzymatic monitorization. The enzymes arylsulphatase, β-glucosidase, dehydrogenase and phosphatase were used as biomarkers of the microbial metabolic activity. The viability cellular assays revealed a relationship with the degradation levels of the paintings. In this way, the metabolic activity of the microbial population can be correlated with the contamination levels detected and with biodegradation and biodeterioration status of the paintings. Therefore, enzymatic approaches constitute good biomarkers to be applied in this research field and are useful to detect biodeteriogenic and biodegradation agents. [ABSTRACT FROM AUTHOR]

This paper describes the deterioration and preservation of an Ancient Egyptian polychrome wooden coffin, dating back to the 1st century. Common deterioration problems are the wood splitting and cracking, detachment of ground and paint layers, fungal damage, dirt adhesion and staining. The project entails securing the severely damaged wood, preparation of lime layer, the painting layer, and paint layer to a substrate, by consolidation, cleaning, dust removal and treatment of the degraded wood. Qualitative analysis of samples selected from the coffin, was reported. Studies that includes the identification of wood species, ground layer, paint layer, binding medium and microbiological identification were made. Several analytical methods were employed in the identification processes such as the Light optical microscopy (LOM), Scanning electron microscopy equipped with energy dispersive X-ray analyzer (SEMEDS), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The obtained data were used to evaluate the deterioration status of the coffin and to establish suitable treatment methods. [ABSTRACT FROM AUTHOR]

Thirteen species of fungi were obtained out of ten samples (five samples of each monument) collected from various places of stone structures of the monuments. Aspergillus fumigatus Fr.species are found in all samples and their percentage frequency is very high. Aspergillus fumigatus Fr., Aspergillus terreus Thom. And Aspergillus flavus fungal species are common on stone of the monument. There should be given priority to the characteristic features of stone structures, their different forms, designs and materials in finding the cause(s) of their degradation and deterioration) This study infers that in the degradation and deterioration of stone there is equal contribution by microbes and the design of stone structures. Hence the nature of the substrate, the relation between substrate and organism, the relation between the design and growth of organism, their frequency distribution are essential components in stone monument preservation interventions. [ABSTRACT FROM AUTHOR]

Microcolonial black fungi have their natural ecological niche on rocks and walls ofhypogean environments, playing an important role in the deterioration of materials and aesthetical alteration of monumental stones and mortars. Three black fungi (Sarcinomyces sp., Pithomyces sp. and Scolecobasidium sp.) have been isolated from cultural assets of historical interest. These fungal strains have been used to test the microwave heating method as a new control methodology for eradicating the fungal biological growth on cultural stone artifacts. This methodology is based on a 2.45 GHz microwave electromagnetic radiation, generated by a new apparatus with an appropriate applicator. The first results showed the best dose of 65°C for three minutes, for all the investigated fungal strains. This methodology is very promising because is safety for the operator and the environment, and can be easily applied on site. The use of this method to kill biodeteriogens can avoid the application of chemicals formulates potentially dangerous for substrates and environment. [ABSTRACT FROM AUTHOR]

Chhattisgarh is a land of ancient culture, with many ancient monuments, temples and forts. Every nook and corner of Chhattisgarh has traditional heritage. There are numerous factors that affect the durability of stone. Stone surfaces are continuously exposed to physical, chemical and biological degradation. Physical, chemical, and biological agents act in co association, ranging from synergistic to antagonistic and leading to deterioration. Among biological agents, micro-organisms are of critical importance in stone deterioration. They can cause various damages on the stone surface. Bio deterioration processes result from complex interactions of surface-invading microbes with each other, as well as with the surface material. The ability of fungi to produce pigments and organic acids is crucial for the discoloration and degradation of monuments. Air acts as a vehicle for the dispersion of microorganisms. They are introduced into air from different sources: soil, water, organic waste, plant leaves, sneezes and cough. This investigation focuses on the scientific conservation of The Sita Devi Temple of Deorbija DistricDurg, [Chhattisgarh]. The stone surface of the temple grew dark due to deposits of dust, dirt, dried vegetation and the growth of micro vegetation on the exterior as well as the interior portions. [ABSTRACT FROM AUTHOR]

Five natural antibiofoulanis with terrestrial (capsaicine - CS, cinnatnaldehyde - Cl) and marine origin (zosteric acid - ZA, poly-alkylpyridinium salts - pAPS and Ceramium bofryocarpum extract - CBE) have been selected and tested against phototrophic biojilin formation on the stone surfaces for their inhibitory properties. The antibiofouling agents (ABAs) were incorporated into two commercial silicone based coatings (Silres BS OH 100 - S and Silres BS 290 - W). in this work, pholotrophic growth was evaluated by epifluorescence microscopy and semi-quantitative image analysis. The results showed on inhibitory efficiency for almost all tested ABAs. However, this efficiency has been found for short time or when the incorporating agent were incompletely cured. Among the ABAs tested, the poly-alkylpyridinium salts and cinnamaldehyde incorporated into Silres BS 290 showed the best inhibitory efficiency. [ABSTRACT FROM AUTHOR]