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The different organisms, ranging from plants to bacteria, and viruses that dwell on built cultural heritage can be passive or active participants in conservation processes. For the active participants, particular attention is generally given to organisms that play a positive role in bioprotection, bioprecipitation, bioconsolidation, bioremediation, biocleaning, and biological control and to those involved in providing ecosystem services, such as reducing temperature, pollution, and noise in urban areas. The organisms can also evolve or mutate in response to changes, becoming tolerant and resistant to biocidal treatments or acquiring certain capacities, such as water repellency or resistance to ultraviolet radiation. Our understanding of the capacities and roles of these active organisms is constantly evolving as bioprotection/biodeterioration, and biotreatment studies are conducted and new techniques for characterizing species are developed. This brief review article aims to shed light on interesting research that has been abandoned as well as on recent (some ongoing) studies opening up new scopes of research involving a wide variety of organisms and viruses, which are likely to receive more attention in the coming year

The irregular damp dark staining on the stonework of a salt-contaminated twelfth century granite-built chapel is thought to be related to a non-homogeneous distribution of salts and microbial communities. To enhance understanding of the role of microorganisms in the presence of salt and damp stains, we determined the salt content and identified the microbial ecosystem in several paving slabs and inner wall slabs (untreated and previously bio-desalinated) and in the exterior surrounding soil. Soluble salt analysis and culture-dependent approaches combined with archaeal and bacterial 16S rRNA and fungal ITS fragment as well as with the functional genes nirK, dsr, and soxB long-amplicon MinION-based sequencing were performed. State-of-the-art technology was used for microbial identification, providing information about the microbial diversity and phylogenetic groups present and enabling us to gain some insight into the biological cycles occurring in the community key genes involved in the different geomicrobiological cycles. A well-defined relationship between microbial data and soluble salts was identified, suggesting that poorly soluble salts (CaSO4) could fill the pores in the stone and lead to condensation and dissolution of highly soluble salts (Ca(NO3)2 and Mg(NO3)2) in the thin layer of water formed on the stonework. By contrast, no direct relationship between the damp staining and the salt content or related microbiota was established. Further analysis regarding organic matter and recalcitrant elements in the stonework should be carried out

[EN] Featured Application This work has developed an innovative and optimized in situ high dimension bio-desalination application protocol that has been applied for the bio-desalination of the 233 m(2) Conxo Chapel granite pavement. This optimized protocol has the potential to be transferable to other large scale in situ biocleaning strategies. Biocleaning technology is based on the use of safe environmental microorganisms for green cultural heritage (CH) restoration. Compared with traditional cleaning products, this biological technique is very specific, effective, and nontoxic. This innovative biotechnological application has been used for recovering diverse monuments and artworks. Most CH in situ surfaces that are treated with microorganisms are small areas; however, some important pathologies, such as salt contamination, can affect high dimension artistic surfaces. The purpose of this study is to analyze and overcome the problems and limitations of scaling up the bio-desalination protocol for in situ applications. Three water-based gel delivery systems and three heating systems were tested in situ and evaluated in terms of performance difficulty, efficacy, and costs. The tests were carried out on the salt contaminated granite pavement of Cristo Chapel of Sta Ma de Conxo in Santiago de Compostela (Spain). Ground agar 2% and a heating electric mat were selected as the best performing systems. The implemented protocol was applied for the bio-desalination of the 233 m(2) Chapel pavement. Conductivity, nitrate-nitrite measurements, biological monitoring, and digital image analysis were performed to determine the efficacy of the treatment. This research allowed for the development of an innovative and optimized in situ, high dimension bio-desalination application protocol transferable to other large scale, in situ biocleaning strategies.

[ES] Muchas veces nos hemos podido preguntar si de verdad los recursos multimedia que empleamos en nuestras asignaturas son los más adecuados. Recursos que implican una importante labor de preparación por parte del profesorado. Pero ¿de verdad cumplen, o alcanzan, lo que se persigue?, ¿son utilizados?, o ¿implican más problemas, que soluciones?, pueden ser algunas de las preguntas que nos podemos hacer una vez terminada la tarea. En la asignatura «Fotografía y Documentación Aplicada al Estudio de los Bienes Culturales» de tercero de Grado en Conservación y Restauración de Bienes Culturales (Facultad de Bellas Artes, Universitat Politècnica de València), hemos decidido hacer una rápida prueba de control para poder determinar algunas variables que pueden ayudar a trabajar mejor estos contenidos. En esta asignatura se ha tenido la oportunidad de trabajar de forma paralela con dos grupos de alumnos/as a los que se les ha facilitado una batería de recursos online diferentes. A través de una encuesta a ambos grupos se ha recogido el uso y la valoración que hacían de los recursos multimedia disponibles para el apoyo al aprendizaje de las herramientas informáticas necesarias para el desarrollo de los ejercicios y tareas asignadas en la asignatura., [EN] We have asked ourselves many times if the multimedia resources that we use in our subjects are really the most appropriate. Resources that entail an important preparation work on the part of the teaching staff. But, do they really fulfill or achieve what is being pursued? Are they used or involve more problems than solutions? These may be some of the questions we can ask ourselves once the task is done. In the third year subject "Photography and documentation applied to the study of cultural heritage" of the Bachelor's Degree in Conservation and Restoration of Cultural Heritage from the Faculty of Fine Arts of the Universitat Politècnica de València, we have decided to do a quick control test in order to determine some variables which can help to work better these contents. In this subject, we have the opportunity to work in parallel with two groups of students who have been provided with a battery of different online resources. Through a survey of both groups, the use and assessment they made of the available multimedia resources has been collected i order to support the learning of the computer tools needed for the development of the exercises and tasks assigned in this subject.

[EN] The first academic studies on the use of microorganisms in cleaning procedures appeared in the late 1980s/early 1990s. In the past thirty years, most of such studies have addressed the removal of nitrate and sulphate salts and organic matter from surfaces by using non-pathogenic anaerobic microorganisms, mainly sulphate-reducing bacteria. The successful use of microbes in the removal of graffiti paint remains, however, a work in progress. Biocleaning surfaces to remove graffiti is not a simple task, because of the complex chemical composition of graffiti paints. This study looks at ways of improving the bioremoval of graffiti and presents the latest findings regarding different methodological aspects of cleaning natural and man-made stone. Granite and concrete substrates were coated with silver and black graffiti spray paints for comparison of the efficacy of the biocleaning method on these different materials. Visual and microscopic examination along with colour and infrared measurements made after application of the bacterial strains tested (previously shown to be suitable candidates for bioremoval of graffiti) revealed remarkably successful results. The findings presented thus represent progress in the development of a biocleaning protocol applicable to the in-situ removal of graffiti. Important improvements have been made regarding the time of treatment, which has been reduced by up to 20 days, and the use of a culture medium enriched with powdered graffiti, which facilitates and accelerates the adaptation of the microorganisms to the target surface.

The first academic studies on the use of microorganisms in cleaning procedures appeared in the late 1980s/early 1990s. In the past thirty years, most of such studies have addressed the removal of nitrate and sulphate salts and organic matter from surfaces by using non-pathogenic anaerobic microorganisms, mainly sulphate-reducing bacteria. The successful use of microbes in the removal of graffiti paint remains, however, a work in progress. Biocleaning surfaces to remove graffiti is not a simple task, because of the complex chemical composition of graffiti paints. This study looks at ways of improving the bioremoval of graffiti and presents the latest findings regarding different methodological aspects of cleaning natural and man-made stone. Granite and concrete substrates were coated with silver and black graffiti spray paints for comparison of the efficacy of the biocleaning method on these different materials. Visual and microscopic examination along with colour and infrared measurements made after application of the bacterial strains tested (previously shown to be suitable candidates for bioremoval of graffiti) revealed remarkably successful results. The findings presented thus represent progress in the development of a biocleaning protocol applicable to the in-situ removal of graffiti. Important improvements have been made regarding the time of treatment, which has been reduced by up to 20 days, and the use of a culture medium enriched with powdered graffiti, which facilitates and accelerates the adaptation of the microorganisms to the target surface

This is the peer reviewed version of the following article: Ranalli, Giancarlo, Zanardini, E. , Andreotti, A. , Colombini, M.P. , Corti, C. , Bosch-Roig, Pilar, De Nuntiis, P., Lustrato, G. , Mandrioli, P. , Rampazzi, L. , Giantomassi, C. , Zari, D. . (2018). Hi-tech restoration by two-steps biocleaning process of Triumph of Death fresco at the Camposanto Monumental Cemetery (Pisa, Italy).Journal of Applied Microbiology, 125, 3, 800-812. DOI: 10.1111/jam.13913 , which has been published in final form at http://doi.org/10.1111/jam.13913. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving., [EN] AimsIn this work, the hi-tech' complex biocleaning and restoration of the 14th-century fresco Triumph of Death (56x150m) at the Camposanto Monumental Cemetery (Pisa, Italy) is reported. Since 2000, the restoration based on the biological cleaning of noble medieval frescoes, has been successfully utilized in this site. Methods and ResultsThe novelty of this study is the two-steps biocleaning process using Pseudomonas stutzeri A29 viable cells, previously applied for recovering other valuable frescoes. In this case, after the fresco detachment from the asbestos-cement support (eternity), both the animal glue and the residues of calcium caseinate were biologically removed respectively from the front and from the back of the fresco in 3h as indicated by GC-MS and PY/GC-MS analyses. The data obtained during the monitoring of the biorestoration process confirmed that the adopted procedure does not leave residual cells on the fresco surfaces as showed by plate count method, ATP determination and also SEM observation. In addition, to avoid the risk of condensation phenomena after the relocation of the restored fresco sections onto the original walls, the use of a new support has been set up together with the design of a control system that allows a continuous monitoring of environmental parameters for prevention and conservation purposes. ConclusionsThis large-scale biorestoration work clearly shows and confirms that this biotechnology is highly efficient, safe, noninvasive, risk-free and very competitive compared to the traditional cleaning methods, offering an unusual resurrection' of the degraded artworks also in very complicated and delicate conditions such as the Triumph of Death fresco, defined for its dimension and artistic importance the Pisa's Sistina frescoes'. Significance and Impact of the StudyThese findings can be of significant importance for other future new restoration activities and they are crucial for determining preservation strategies in this fiel

[ES] En el marco de la restauración de las pinturas murales y revestimiento ornamental de la nave central de la Iglesia Parroquial de San Nicolás Obispo y San Pedro Mártir de Valencia, se propone una metodología de intervención que contempla tanto la estricta intervención restaurativa como los pertinentes trabajos de apoyo, control y definición de pautas de conservación del conjunto intervenido. El presente artículo expone la metodología empleada y los primeros resultados de la monitorización de las condiciones medioambientales, que comprende la toma de datos termo-higrométricos, partículas en suspensión y del nivel de microorganismos presentes en el aire. Para ello se dispone de un sistema de control centralizado con sensores combinados de temperatura y humedad relativa ambiental y de temperatura superficial, situados a lo largo de la nave principal y en el exterior. Con este sistema se pretende la observación en un período anual de las variaciones de la temperatura y humedad relativa en los diferentes espacios que componen el edificio, así como sobre las superficies pictóricas. El sistema permite la obtención y transmisión de datos en tiempo real. Paralelamente se realiza muestreo trimestral (para determinar las variaciones estacionales) de los contaminantes atmosféricos, para el control de la evolución de las partículas en suspensión y microorganismos presentes en el aire, en el ambiente interior de la iglesia. Esta investigación microclimática pretende caracterizar la evolución y tendencias de parámetros psicrométricos en el ambiente objeto de estudio, y poner en relación estos datos con la evolución de las partículas en suspensión y actividad microbiológica en el aire. Este conjunto de sistemas de control permiten por un lado la monitorización de la restauración, y por otro lado la realización de una estrategia de conservación preventiva que permitirá prolongar en el tiempo los resultados de la presente restauración.