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Recent consumer demand for non-dairy alternatives has forced many manufacturers to turn their attention to cereal-based non-alcoholic fermented products. In contrast to fermented dairy products, there is no defined and standardized starter culture for manufacturing cereal-based products. Since spontaneous fermentation is rarely suitable for large-scale commercial production, it is not surprising that manufacturers have started to adopt centuries-known dairy starters based on lactic acid bacteria (LABs) for the fermentation of cereals. However, little is known about the fermentation processes of cereals with these starters. In this study, we combined various analytical tools in order to understand how the most common starter cultures of LABs affect the most common types of cereals during fermentation. Specifically, 3% suspensions of rice, oat, and wheat flour were fermented by the pure cultures of 16 LAB strains belonging to five LAB species—Lacticaseibacillus paracasei, Lactobacillus delbrueckii, Lactobacillus helveticus, Streptococcus thermophilus, and Lactococcus lactis. The fermentation process was described in terms of culture growth and changes in the pH, reducing sugars, starch, free proteins, and free phenolic compounds. The organoleptic and rheological features of the obtained fermented products were characterized, and their functional properties, such as their antioxidant capacity and angiotensin-converting enzyme inhibitory activity, were determined. [ABSTRACT FROM AUTHOR]

As a toxic xenobiotic compound, the anthraquinone dye Remazol Brilliant Blue R (RBBR) poses a serious threat to aquatic ecosystems. In the present study, the ability of Trametes hirsuta to remove RBBR from the medium was investigated, and the role of adsorption by fungal mycelium and biodegradation by fungal enzymes was evaluated. It was shown that the whole fungal culture was able to remove up to 97% of the dye within the first four hours of incubation. Based on enzymatic activities in the culture broth, laccases were proposed to be the main enzymes contributing to RBBR degradation, and RT-qPCR measurements demonstrated an increase in transcription for the two laccase genes—lacA and lacB. Composite mycelial pellets of T. hirsuta with improved adsorption ability were prepared by adding activated carbon to the growth medium, and the induction of laccase activity by carbon was shown. For composite pellets, the RBBR decolorization degree was about 1.9 times higher at 1 h of incubation compared to carbon-free pellets. Hence, it was shown that using fungal mycelium pellets containing activated carbon can be an effective and economical method of dye removal. [ABSTRACT FROM AUTHOR]

The concept «power» has a significant status in the system of global regionalism. All concepts of political research originated in different branches of knowledge. Despite the great attention of scientists, the specific definition of this concept and the various approaches of the academic community cause the complexity and inconsistency to study the concept «power» in political science. Geopolitical space in this century is changing and the challenge of the phenomenon is to make an attractive country image. The national idea and mission of it can be concentrated and used by soft power mechanism in practice. «Soft power» has a goal to create motivation for action and make a decision by an object that has a «soft» effect. Therefore, to study indirect impact on the countries’ politics becomes the most burning. This work analyses the methodological genesis of the concept «Soft Power», gives the features of some theories considering the concept «power», including: classical, political, offensive realism, liberalism, democratic peace, the theory of international organizations, etc.

A conventional UV-vis spectroscopy at pH 3-7 and 25 degree Celsius is employed to study the reactivity of the acido [Ru.sup.II] complexes toward laccase from Coriolus hirsutus. The acido and cyclometalated complexes readily oxidized into the corresponding [Ru.sup.III] species, but differed substantially in reactivity and obey different rate laws.

Laccases are members of a large family of multicopper oxidases that catalyze the oxidation of a wide range of organic and inorganic substrates accompanied by the reduction of dioxygen to water. A new laccase was isolated from the basidiomycete Coriolopsis caperata strain 0677 and its amino-acid sequence was determined. According to its physicochemical properties and spectroscopic features, the laccase from C. caperata is a high redox-potential blue laccase. Attempts to crystallize the native enzyme were unsuccessful. The copper type 2-depleted (T2D) laccase was prepared and crystallized. The structure of T2D laccase from C. caperata was solved at 1.6 Å resolution, and attempts to reconstruct the T2 copper centre were performed using Cu+ and Cu2+ ions. The structure of T2D+Cu+ laccase was solved at 1.89 Å resolution. It was shown that the T2D+Cu+ laccase structure contained four copper ions in the active site. Reconstruction could not be achieved when the T2D laccase crystals were treated with CuSO4. [ABSTRACT FROM AUTHOR]

This paper describes the structural analysis of the native form of laccase from Trametes hirsuta at 1.8 Å resolution. This structure provides a basis for the elucidation of the mechanism of catalytic action of these ubiquitous proteins. The 1.8 Å resolution native structure provided a good level of structural detail compared with many previously reported laccase structures. A brief comparison with the active sites of other laccases is given. [ABSTRACT FROM AUTHOR]

Bioactive peptides derived from milk proteins are an active research area. Exhibiting numerous positive physiological effects on digestive, cardiovascular, immune and nervous systems, these peptides thought to be one of the most promising ingredients for functional food. Generally, these peptides are inactive within the parent proteins and can be liberated during milk fermentation by the specific proteolytic systems of various Lactobacillus spp. Here we present the study of milk fermentation by Lactobacillus helveticus NK1, Lactobacillus rhamnosus F and Lactobacillus reuteri LR1 strains. It was demonstrated that the antioxidant activity of the milk fermented by these strains concomitantly increased with the strains' proteolytic activity. For the angiotensin I-converting enzyme (ACE) inhibitory activity, the same tendency was not observed. Although the proteolytic activity of L. helveticus NK1 was two times higher than that of L. rhamnosus F, the milk fermented by these strains showed comparable ACE inhibition. The analysis of the peptide profiles of the fermented milk samples allowed us to hypothesize that some previously unreported peptides can be produced by L. rhamnosus F. In addition, it was demonstrated that these potential ACE-inhibiting peptides originated from the C-terminus of αS2-casein. [ABSTRACT FROM AUTHOR]

Laccases are copper-containing oxidases that catalyze a one-electron abstraction from various phenolic and non-phenolic compounds with concomitant reduction of molecular oxygen to water. It is well-known that laccases from various sources have different substrate specificities, but it is not completely clear what exactly provides these differences. The purpose of this work was to study the features of the substrate specificity of four laccases from basidiomycete fungi Trametes hirsuta, Coriolopsis caperata, Antrodiella faginea, and Steccherinum murashkinskyi, which have different redox potentials of the T1 copper center and a different structure of substrate-binding pockets. Enzyme activity toward 20 monophenolic substances and 4 phenolic dyes was measured spectrophotometrically. The kinetic parameters of oxidation of four lignans and lignan-like substrates were determined by monitoring of the oxygen consumption. For the oxidation of the high redox potential (>700 mV) monophenolic substrates and almost all large substrates, such as phenolic dyes and lignans, the redox potential difference between the enzyme and the substrate (ΔE) played the defining role. For the low redox potential monophenolic substrates, ΔE did not directly influence the laccase activity. Also, in the special cases, the structure of the large substrates, such as dyes and lignans, as well as some structural features of the laccases (flexibility of the substrate-binding pocket loops and some amino acid residues in the key positions) affected the resulting catalytic efficiency. [ABSTRACT FROM AUTHOR]