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Microbial-induced calcite precipitation (MICP) is an innovative technology in civil engineering. However, the high cost of components and the fragility of the treated soil limit its wide use. One of the possible solutions is organic waste incorporation at different stages of the technology. In the present study, we consider the use of spent brewer's yeast (BSY) to produce bacterial inoculates and wastepaper, flax shives and sawdust as reinforcing additives into the soil. We showed that the replacement of expensive components of LB medium by BSY extract increased biomass growth characteristics of Bacillus subtilis K51, B. cereus 4b and Micrococcus luteus 6 strains by 1.4, 1.5 and 1.8 times, respectively, while for B. subtilis 168, they were comparable to LB medium. The urease activities of all strains were not reduced compared to the control. Among the three kinds of cellulose-containing waste, wastepaper incorporation into MICP-treated soil samples led to an increase in compressive strength by 2.1 times and precipitated calcite percentage by almost 1.5 times compared to a sample without additives. Thus, we showed the potential for soil stabilization through MICP using organic waste. [ABSTRACT FROM AUTHOR]

Biomineralization is a universal process that has implications in a variety of areas, from civil engineering to medicine. While crystallization of amorphous CaCO3 formed in vitro is known to precede the vaterite-calcite/aragonite pathway, this process could be significantly altered when induced by bacteria, particularly within the extracellular matrix (ECM) of microbial cells. We used a combination of SEM, SANS, SAXS, FTIR and XRD methods to investigate the structure of CaCO3 formed during biomineralization induced by planktonic Bacillus cereus. Formation of precipitates in the presence of CaCl2 and urea was observed both during bacterial growth and in the medium devoid of bacteria and ECM (cell-free system). The pathway for polymorphic transformations of CaCO3 from the amorphous phase to vaterite and further to calcite was confirmed for the bacterium-induced mineralization and did not depend on the concentration of Ca2+ and urea. The structure of CaCO3 sediments differed when formed in cell-free and bacterial systems and varied depending on time and the medium composition. The rate of precipitation was accelerated in the presence of DNA, which had little effect on the solid phase structure in the cell-free system, while strongly affecting the structure and polymorphic composition of the precipitates in bacterial culture. [ABSTRACT FROM AUTHOR]

Kombucha tea was made by the fermentation of SCOBY culture of green tea broth with the addition of Fucus vesiculosus algae extract, Cetraria islandica lichen extract and their mixture. Kombucha was also made without the herbal supplements as a control. After 11 days of fermentation, in addition to the yeast Brettanomyces bruxellensis and the bacteria Komagataeibacter rhaeticus and Komagataeibacter hansenii contained in all of the samples, the yeast Zygosaccharomyces bailii and bacteria Komagataeibacter cocois were detected in the samples with the herbal extracts. In all of the kombucha with herbal additives, the total fraction of yeast was decreased as compared to the control. The total content of polyphenols and the antioxidant activity of the beverages with and without the addition of herbal extracts were comparable. The kombucha made with the algae extract showed an increased content of sucrose and organic acids, while the fructose and glucose content in the samples with algae and the mixture of extracts were lower than in the other samples. The samples with the algae extract had the highest organoleptic indicators "aroma", "clarity" and "acidity", while the control samples had slightly higher indicators of "taste" and "aftertaste". The results of this study indicate the potential of algae and lichens as functional supplements for obtaining non-alcoholic fermented beverages with additional nutraceutical value. [ABSTRACT FROM AUTHOR]

The organization of glycoside hydrolase (GH) families into clans is examined for GH27and GH36 by using biochemical analysis of GH36 [alpha]-galactosidase from Thermotoga maritima (TmGaIA). The results have shown that Asp387 is the acid/base residue of TmGaIA and the biochemical characteristics of GH36 TmGaIA are closely related to GH27 enzymes, confirming the mechanistic commonality of clan GH-D members.

The enzyme beta-xylosidase from Trichoderma reesei, a member of glycosil hydrolase family 3 (GH3), is a glycoside hydrolase which acts at the glycosidic linkages of 1,4-Beta-xylooligosaccharides and that also exhibits alpha-L-arabinofuranosidase activity on 4-nitrophenyl Alpha-L-arabinofuranoside. Enzyme forms monomers in solution and derive that low-resolution molecular envelope of the Beta-xylosidase from small-angle X-ray scattering (SAXS) data using the ab ignition simulated annealing algorithm.

Research has been conducted on Trichoderma reesei beta-mannosidase molecular envelope. Results indicate that this envelope has been produced via the use of small-angle X-ray scattering and protein crystallography and that the beta-mannosidase's molecular fold is similar to the one of beta-galactosidase.

In the 1970s, the strain Geotrichum candidum Link 3C was isolated from rotting rope and since then has been extensively studied as a source of cellulose and xylan‐degrading enzymes. The original identification of the strain was based only on morphological characters of the fungal mycelium in culture. Recent comparison of the internal transcribed spacer (ITS) fragments derived from the draft genome published in 2015 did not show its similarity to G. candidum species. Given the value of the strain 3C in lignocellulosic biomass degradation, we performed morphological and molecular studies to find the appropriate taxonomic placement for this fungal strain within the Ascomycota phylum. ITS, 18S rDNA, 28S rDNA sequences, and RPB2 encoding genes were used to construct phylogenetic trees with Maximum likelihood and Bayesian inference methods. Based on sequence comparison and multiple gene sequencing, we conclude that the fungal strain designated as Geotrichum candidum Link 3C should be placed into the genus Scytalidium (Pezizomycotina, Leotiomycetes) and is redescribed herein as Scytalidium candidum 3C comb. nov. [ABSTRACT FROM AUTHOR]