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This study proposes a method for the chamber disinfection of paper with biocide in the form of fine, volatile droplets using antifungal Rocima GT. This method provides a fungicidal effect, and within a short exposure time, a fungistatic one. At a concentration of 5% Rocima GT solution, the minimum treatment time to ensure the complete disinfection of paper was 15 min. The proposed method of disinfection by a chemical mist was less harmful to paper than disinfection using a swab saturated in a biocide solution. It was noted that when using Rocima GT at insufficient concentrations to inhibit fungal growth completely, Rocima GT can induce, as well as suppress, organic acid produced by Aspergillus niger depending on the concentration.

Three Sparassis crispa strains from the Komarov Botanical Institute Basidiomycetes Culture Collection (LE-BIN) were studied on various agar and liquid media for growth and phenol compound production. On agar media, the strains produced crystals of various shapes and sizes that glowed in ultraviolet light and were visible to the naked eye. Using gas chromatography-mass spectrometry, the crystals were identified as sparassol (methyl 2-hydroxy-4-methoxy-6-methylbenzoate). Other phenol compounds (i.e., methyl ester of sparassol and methyl ester of orsellinic acid) were also found in S. crispa mycelium. Phenol compounds were detected both in the mycelium and culture filtrate of all studied strains cultivated on various agar and liquid media, at different acidity and duration, but their composition and ratio varied. The initial pH of cultivated medium did not have a large influence on phenol compound production, unlike culture growth duration, which correlated directly with sparassol concentration in mycelium. Production of the phenol compounds presumably connected with constitutive processes of Sparassis metabolism, but the intensity of their production and accumulation in mycelium depends on the strain, conditions, and cultivation time. Strain LE-BIN 2902 is considered a promising sparassol producer.

GC–MS-based metabolomic profiling of different strains of basidiomycetes Lignomyces vetlinianus, Daedaleopsis tricolor and Sparassis crispa were studied. On different stages of growth in the methanol extracts of mycelium the different compounds including amino acids, organic acid of TCA cycle, sugars, fatty acids, sugar alcohols, and sugar acids were detected. Changes in the metabolite network occurring with age of the mycelium of L. vetlinianus and D. tricolor are discussed. The exponential phase of mycelium growth is characterized by pronounced differences during of growth, which manifests itself both in the analysis of specific compounds and in the modeling of the statistical model of the metabolic network. The metabolomic network in the stationary growth phase is less susceptible to changes over time, and is also characterized by a lower dispersion of samples from one aging group. For some compounds, including biotechnologically significant ones, targeted analysis by GC–MS was performed. 4, 6-dimethoxy-phthalide (4, 6-dimetoxy-1 (3H) -isobenzofuranone) was isolated from the mycelium of Lignomyces vetlinianus, accumulating in the mycelium in the form of large aggregates. The accumulation of sparassol and other orsellinic acid derivatives in Sparassis crispa culture under various conditions is described.

The pattern of elements accumulation in biodeposits formed by living organisms and extracellular products of their metabolism (biofouling, primary soils) on different bedrocks (of the monuments of Historical necropoleis in Saint Petersburg) were studied by a complex of biological and mineralogical methods (optical microscopy, SEM, EDX, XRD, ICP MS, XRFS). The content of 46 elements in biodeposits with various communities of microorganisms is determined. The model recreating the picture of the input and selective accumulation of elements in biodeposits on the stone surface in outdoor conditions is assumed. It is shown that the main contribution to the elemental composition of biodeposits is made by the environment and the composition of the microbial community. The contribution of leaching under the action of microbial metabolites of mineral grains, entering biodeposits from the environment, is significantly greater than that of the underlying rock.

Rock surfaces in natural systems are inhabited by multispecies communities of microorganisms. The biochemical activity of microorganisms and the patterns of microbial crystallization in these communities are mostly unexplored. Patterns of calcium carbonate and calcium oxalate crystallization induced by bacteria Bacillus subtilis and by B. subtilis together with Aspergillus niger on marble surface in vitro in liquid medium and in humidity chamber&mdash, were studied. Phase identification was supported by XRD, SEM, EDXS, metabolite composition was determined by GC&ndash, MS. It was found that the activity of B. subtilis&ndash, A. niger associations significantly differ from the activity of B. subtilis monocultures in the same trophic conditions. The phase composition and the morphology of the forming crystals are determined by the composition of the metabolites excreted by the microorganisms&mdash, particularly by the ratio of the concentrations of extracellular polymeric substances (EPS) and oxalic acid in the medium. The acidification activity of micromycetes may suppress the formation of bacterial EPS and prevent the formation of calcite. The present results can be used in the development of biotechnologies using microbial communities.

Culture characteristics and metabolomic profiling (on the basis of gas chromatography-mass spectrometry) of 3 strains of Lignomyces vetlinianus were studied. Growth rate, macromorphology, and micromorphology of mycelia grown on various media are described. More than 60 compounds were detected in the mycelial extracts, including amino acids, organic acids that are active during the tricarboxylic acid cycle, sugars, fatty acids, sugar alcohols, and sugar acids. Principal component analysis of low-molecular-weight compounds in mycelial methanol extracts of L. vetlinianus strains at different stages of growth demonstrated that the pattern of mycelial metabolomes grouped by age of the culture indicates a significant relation between the development of the culture and the specificity of its metabolite spectrum. Slow-growing cultures develop gradually and are characterized by several changes in metabolite states. The pattern of points is grouped more tightly for fast-growing strains. The production of crystal-like aggregates was observed for aging mycelia at the stationary phase of growth. These aggregates were isolated from mycelia and identified as clusters of 4,6-dimethoxy-phthalide. The molecular structure of this substance was confirmed by nuclear magnetic resonance analysis. The results show that the concentration of 4,6-dimethoxy-phthalide increased during cultivation. Fruiting bodies contained very small amounts of 4,6-dimethoxy-phthalide compared with amounts in mycelia. It can be assumed that L. vetlinianus is a powerful natural producer of phthalides of biotech-nological interest and can be used as a model to study phenolic metabolism in fungi.

The formation of biolayers of various taxonomic and biochemical composition occurs on the rock surfaces under various environmental conditions. The composition of metabolites in various types of biolayers on the marble surface in natural outcrops and urban environment was studied. Metabolome profiling was fulfilled by GC-MS. It was found that communities in urban environment are much less biochemically diverse than in a quarry. The seasonal differences in metabolite network between samples dominate over taxonomic ones in biolayers with predomination of algae and cyanobacteria and in biolayers with predomination of fungi. The biolayers of different stage of soil formation are less susceptible to seasonal variability.

Granite rapakivi was widely used in the construction of historical buildings in St. Petersburg. This rock was mined in Karelia and southern part of Finland where old quarries are preserved. Biofouling of granite can be observed both in urban environments and in natural outcrops. Biofilms on granite rapakivi have a different structure, composition, speed of development. The aim of this work is the complex analysis of biological colonization of granite rapakivi in different environment. The biodiversity of biofilms was studied on granite monuments of Saint Petersburg as well as in the abandoned quarries of the southern part of Finland. The composition of micromycetes, cyanobacteria and organotrophic bacteria in biofilms was determined at different stages of colonization and destruction of the granite rapakivi. The composition of metabolites in biofilms and sediments on the surface of the rock was determined. More than 200 compounds were found in the samples from the quarry and about 60–100 low molecular weight organic compounds were detected in the samples from the urban environment. Concentration of certain compounds, especially polyols, was significantly higher in biofilms in the urban environment. The main features of biological colonization of granite rapakivi in the urban environment and natural outcrops were shown by scanning electron microscopy. The differences in the character of colonization of feldspar, quartz and mica were revealed. It was found that under the influence of bacteria Bacillus subtilis the intensity of elements leaching from granite minerals in the aquatic environment (model experiment) was significantly increased. Feldspars and mica were destroyed first of all.

The history and temporary changes in the condition of outstanding artistic monuments in the museum Necropoleis, made of various materials, are surveyed: those to A.I. Kosikovsky (Paolo Catozzi and A.I. Terebenev, sculptors, 1840), E.A. and V.N. Kochubey (A. Costoli, sculptor, 1856), A.Ya. Okhotnikov (F. Thibaut, sculptor, 1800s), M.V. Lomonosov (J. Stalin, author of the design, 1766), V.V. Stasov (I.Ya. Ginzburg, sculptor, I.P. Ropet, architect, 1908), P.V. Kindyakov (Paolo Catozzi, sculptor, 1828), N.M. Karamzin (of unknown authorship, 1820s) and E.A. and E.N. Karamzin (of unknown authorship, 1850s), A.Ya. Potemkina (of unknown authorship, 1830s). The materials of the monuments are described, the results of restoration work and dated materials science analyses are given.

A study of the ambient air, soil, vegetation, and biogenic layers on the surface of the monuments was carried out in order to identify environmental factors that have an adverse effect on the condition of the monuments in the Museum necropoleis. It was found out that the corrosivity of the air at the Necropoleis corresponds to the medium category C3 and gradually decreases (primarily due to a reduction in the sulfur dioxide content). The soil near the monuments is another source of contamination of their surface, occurring with the participation of various microorganisms. Selective accumulation of miscellaneous elements on the surface of monuments from the environment and low-molecular organic substances depends, above all, on the species composition of the lithobiont community. The presence of woody plants produces microclimate effects in different parts of the Necropoleis, which has a significant impact on the condition of the monuments.

The crystallization of calcium oxalates (weddellite and whewellite) by interaction of calcite marble with fungus Aspergillus niger , one of the most active stone destructors, was studied under in vitro conditions. The temporal development of acid production of fungus as well as the sequence of formation and morphogenesis of the growing oxalate hydrates crystals were investigated in detail. Furthermore, the relationships between morphology and growth conditions of crystals within the biofilms on the surface of carbonate rocks are discussed.

Heavy metals, Zn and Cu, in high concentration (2 mM for Zn and 0.5 mM for Cu) have some inhibiting effect on the growth of Aspergillus niger and Penicillium citrinum. Toxic effects of these metals considerably depend on cultivation conditions including nitrogen sources, pH of nutrient media, and its consistency (presence or absence of agar). In general, nitrate media provides less inhibiting effect on fungal growth under heavy metal exposure than ammonium-containing media. Adding of Zn in nitrate media induces oxalic acid production by fungi. Importance of oxalic acid production in detoxification of heavy metals is confirmed by the formation of Zn-containing crystals in fungal cultures. Cu bringing to the cultural media had no stimulating effect on oxalic acid production as well as no copper-containing crystals were observed. But proceeding from essential increase in oxalic acid production during a long-term fungi adaptation to Cu, it may be proposed that oxalic acid plays some functional role in Cu tolerance of fungi as well. It may be concluded that the role of organic acids and oxalate, in particular, in fungi tolerance and adaptation to heavy metals can be determined by the nature of the metal and its ability to form stable complexes with an acid anion. Stimulating effect of metals on acid production is not universal for all species of fungi and largely depends on metal concentration, nitrogen form in a medium, and other cultivation conditions.

The single-crystal structures of four biomimetic weddellites CaC2O4 · (2 + x)H2O with different contents of zeolitic water (x = 0.10–0.24 formula units) produced by the microscopic fungus Aspergillus niger were refined from X-ray diffraction data (R = 0.029–0.038). The effect of zeolitic water content on the structural stability of weddellite was analyzed. The parameter a was shown to increase with increasing x due to the increase in the distance between water molecules along this direction. The water content and structural parameters of the synthesized weddellites are similar to those of weddellites from biofilms and kidney stones.

According to the results of screening acidification activity of 24 species of micromycetes in vitro, 18 of them produced organic acids in artificial medium. The fungi from genera Penicillium and strains of Aspergillus niger have the most active production of organic acids. The ratio of acids formed by fungi on a liquid glucose-containing medium changes during ontogenesis: gluconic acid and acids of the Krebs cycle dominated in a log phase of growth; oxalic acid accumulated in a stationary phase while concentrations of other organic acids reduced. Oxalic acid is the main acid produced by fungi in a culture and apparently in a natural habitat. Formation of gluconate improves the efficiency of other carbon substrates consumption by fungi. Citric, succinic, malic, and fumaric acids are produced only at higher concentrations of carbohydrate and high ratio of C/N. Production of oxalic acid by micromycetes increases on the media containing only nitrate nitrogen. Zn in concentration up to 2 mM induces secretion of oxalic acid on nitrate media. Copper has stimulation effect on oxalic acid production only in very low concentration (25 µM). Presence of Zn in culture leads to formation of oxalate Zn crystals on the surface of mycelium. On ammonium-containing culture Zn and Cu does not stimulate oxalic acid production, but induce significant morphological changes.