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Cueva del Viento, located in the Canary Islands, Spain, is the Earth's sixth‐longest lava tube, spanning 18,500 m, and was formed approximately 27,000 years ago. This complex volcanic cave system is characterized by a unique geomorphology, featuring an intricate network of galleries. Despite its geological significance, the geomicrobiology of Cueva del Viento remains largely unexplored. This study employed a combination of culture‐dependent techniques and metabarcoding data analysis to gain a comprehensive understanding of the cave's microbial diversity. The 16S rRNA gene metabarcoding approach revealed that the coloured microbial mats (yellow, red and white) coating the cave walls are dominated by the phyla Actinomycetota, Pseudomonadota and Acidobacteriota. Of particular interest is the high relative abundance of the genus Crossiella, which is involved in urease‐mediated biomineralization processes, along with the presence of genera associated with nitrogen cycling, such as Nitrospira. Culture‐dependent techniques provided insights into the morphological characteristics of the isolated species and their potential metabolic activities, particularly for the strains Streptomyces spp., Paenarthrobacter sp. and Pseudomonas spp. Our findings underscore the potential of Cueva del Viento as an ideal environment for studying microbial diversity and for the isolation and characterization of novel bacterial species of biotechnological interest. [ABSTRACT FROM AUTHOR]

The Alcobacenses are one of the most important Portuguese collections of Monastic codices. During a campaign study to further advance our knowledge on this important legacy and its state of conservation, a heavily deteriorated codex (ALC.338) stood out due to the presence of purple stains on the lower margins on virtually all folios. In some of them, the purple stains are accompanied by yellow and brown patches as well. Also noticed was the presence of these purple spots on the white tawed leather covering the codex. The codex was analyzed macro and microscopically, chemically and biologically using state-of-the-art technology such as next-generation sequencing. The biological deterioration associated with the appearance of these purple spots arises from the inside out and reveals significant abundance of the bacterial genus Saccharopolyspora sp., which accounted for 86% of the bacterial genera identified. For the fungal population, the most common genus was Malassezia sp. Visual inspection of the sample confirmed the presence of fungal and bacterial biofilms. Pressing questions, comparison to similar studies and future perspectives are also given. [ABSTRACT FROM AUTHOR]

The analyzed systems were the following: silica nanocapsules (NC) and silica nanoparticles (MNP) not loaded with biocides, two nanosystems loaded with ZS and MBT, and free biocides. The two biocides selected were: Zosteric sodium salt (ZS), a green biocide, and the commercial biocide, 2-mercaptobenzothiazole (MBT), widely used in the treatment of cultural heritage. This Special Issue of the I Applied Sciences i , entitled "Application of Biology to Cultural Heritage" aimed to cover all the latest outstanding progress of biological and biochemical methods developed and applied to cultural heritage. Full research articles and reviews on all aspects of biological causes, modes of action, biocidal treatment, protection, and prevention of cultural heritage, are here presented as well as long term studies on the biodeterioration of cultural heritage sites and monuments. [Extracted from the article]

The lichen Circinaria gyrosa is an astrobiological model defined by its high capacity of resistance to space conditions and to a simulated martian environment. Therefore, it became part of the currently operated BIOMEX experiment on board the International Space Station and the recent STARLIFE campaign to study the effects of four types of space-relevant ionizing radiation. The samples were irradiated with helium and iron ions at doses up to 2 kGy, with X-rays at doses up to 5 kGy and with γ rays at doses from 6 to 113 kGy. Results on C. gyrosa's resistance to simulated space ionizing radiation and its post-irradiation viability were obtained by (i) chlorophyll a fluorescence of photosystem II (PSII), (ii) epifluorescence microscopy, (iii) confocal laser scanning microscopy (CLSM), and (iv) field emission scanning electron microscopy (FESEM). Results of photosynthetic activity and epifluorescence show no significant changes up to a dose of 1 kGy (helium ions), 2 kGy (iron ions), 5 kGy (X-rays)-the maximum doses applied for those radiation qualities-as well as a dose of 6 kGy of γ irradiation, which was the lowest dose applied for this low linear energy transfer (LET) radiation. Significant damage in a dose-related manner was observed only at much higher doses of γ irradiation (up to 113 kGy). These data corroborate the findings of the parallel STARLIFE studies on the effects of ionizing radiation on the lichen Circinaria gyrosa, its isolated photobiont, and the lichen Xanthoria elegans. Key Words: Simulated space ionizing radiation-Gamma rays-Extremotolerance-Lichens- Circinaria gyrosa-Photosynthetic activity. Astrobiology 17, 145-153. [ABSTRACT FROM AUTHOR]

The article presents a study that reviews the literature on cyanobacteria and chlorophyta that give rise to the worsening of outdoor monuments and works of art in European countries of the Mediterranean Basin. An analysis was made for some 45 case studies from 32 scientific papers printed between 1976 and 2009. The study considered six lithotypes which include marble, limestone and travertine. The results indicate that cyanobacteria and chlorophyta colonize a diversity of substrata.

Historical glazed wall tiles are a unique vehicle of artistic expression that can be found outdoors, integrating the buildings of many countries, therefore they are often subjected to biodeterioration. In this work, the applicability of protective coatings on glazed tiles to prevent biological colonization was evaluated. Thin films of titanium dioxide (TiO2) obtained by sol-gel were applied on glazed tiles to appraise its anti-biofouling properties and to evaluate their suitability for cultural heritage application. The TiO2 coating was tested on four different Portuguese glazed tiles and a modern tile. The chemical and mineralogical characterization of the glaze and ceramic body of the tiles was examined by wavelength dispersive X-ray fluorescence spectroscopy (WDXRF) and X-ray diffraction (XRD). The produced TiO2 coating was chemically and morphologically characterized by micro Raman spectroscopy (µ-Raman) and field emission scanning electron microscopy (FESEM). The anti-biofouling properties of the TiO2 treatment were evaluated by inoculating the fungus Cladosporium sp. on the glazed tiles. Potential chromatic and mineralogical alterations induced by the treatment were assessed by color measurements and XRD. The TiO2 coating did not prevent fungal growth and caused aesthetical alterations on the glazed tiles. A critical analysis evidenced that the tested coating was not suitable for cultural heritage application and highlighted the challenges of developing protective coatings for glazed tiles. [ABSTRACT FROM AUTHOR]

Unlike the spectacular speleothems that can often be found in numerous caves, vermiculations are rather unassuming formations, whose origin and evolution still subject of several heated debates. In order to provide a quantitative basis for the understanding of the nature and evolution of vermiculations in karst environments, the geochemical properties of one of the most important karst systems of southern Italy, the Pertosa-Auletta Cave, were studied through a comprehensive approach which included elemental, mineralogical and microscopy analyses. The chemical element abundances, mineral composition and microstructure of the vermiculations covering the entire range of morphologies and colours observed in the case-study cave were investigated, thus providing the first quantitative record of these traits. The vermiculations presented exceptional diversity in their morphology, colour, chemical and mineral composition, with it being due to exogenous determinants such as the deposition of stream sediments or organic matter as well as the development of photoautotrophic communities. They were invariably composed of calcite, associated to quartz as well as clays and other secondary minerals, the formation of which may be biologically mediated. This occurrence, and the evidences of microbial activity observed through dissolution traces, support the possible involvement of biogenic processes in vermiculation development. • Morphology, chemistry and mineralogy of vermiculations have been investigated. • Vermiculations from Pertosa-Auletta Cave exhibit exceptional diversity. • Local and broad-scale factors contribute to vermiculation diversity. • Clays and other minerals on a calcite matrix constitute vermiculations. • Microbial involvement in micro-scale vermiculation traits has been documented. [ABSTRACT FROM AUTHOR]