Características comparativas da estabilidade térmica dos ácidos húmicos dos sapropels da região OB do meio e sul da bacia de OB-Irtysh da Sibéria Ocidental

The study of humic acids has more than a century history with a natural and logical evolution of focuses on their development processes, composition and properties. Despite the considerable material accumulated to date, the nature of this group of organic compounds still has not been sufficiently studied. We have decided that the distinctive features of hydrochemical and hydrobiological factors in the formation of sapropels of the studied lakes will be reflected in the thermal stability of humic acids extracted from them. Thermal analysis of humic acids extracted from the upper layers of bottom sediments of lakes of Kondinsk district of Khanty-Mansi Autonomous okrug and Barabinsk district of the Novosibirsk region, made using modern synchronous thermal analysis, has been resulted in the article. According to the obtained data, it is observed that with increasing of maximum temperature of the thermal effect, the value of Z decreases (the ratio of the mass loss in the low temperature space to the mass loss in the high temperature space), which indicates the increase in thermal stability, formation of humic acids. The indicator of humic acids of sapropels of the Kondinsk lakes varies from 0,56 to 0,67, and these intervals are much wider from 0.45 to 0.75 in the Barabinsk lakes. According to thermogravimetric analysis the only statement of changes in chemical structure is possible, and the direction of the process can be assumed taking into account the data of the structural chemistry in combination with other spectral and chemical analysis methods.El estudio de los ácidos húmicos tiene más de un siglo de historia con una evolución natural y lógica de enfoques en sus procesos de desarrollo, composición y propiedades. A pesar del considerable material acumulado hasta la fecha, la naturaleza de este grupo de compuestos orgánicos aún no ha sido suficientemente estudiada. Hemos decidido que las características distintivas de los factores hidroquímicos e hidrobiológicos en la formación de sapropeles de los lagos estudiados se reflejarán en la estabilidad térmica de los ácidos húmicos extraídos de ellos. El resultado del análisis térmico de los ácidos húmicos extraídos de las capas superiores de los sedimentos del fondo de los lagos del distrito de Kondinsk de Okrug Autónomo de Khanty-Mansi y el distrito de Barabinsk de la región de Novosibirsk, realizado con el moderno análisis térmico sincrónico, ha sido publicado. Según los datos obtenidos, se observa que al aumentar la temperatura máxima del efecto térmico, el valor de Z disminuye (la relación entre la pérdida de masa en el espacio de baja temperatura y la pérdida de masa en el espacio de alta temperatura), lo que indica El aumento de la estabilidad térmica, formación de ácidos húmicos. El indicador de ácidos húmicos de sapropeles de los lagos de Kondinsk varía de 0,56 a 0,67, y estos intervalos son mucho más amplios de 0,45 a 0,75 en los lagos de Barabinsk. Según el análisis termogravimétrico, la única declaración de cambios en la estructura química es posible, y la dirección del proceso se puede asumir teniendo en cuenta los datos de la química estructural en combinación con otros métodos de análisis espectral y químico.O estudo dos ácidos húmicos tem mais de um século de história com uma evolução natural e lógica de focos em seus processos de desenvolvimento, composição e propriedades. Apesar do considerável material acumulado até hoje, a natureza desse grupo de compostos orgânicos ainda não foi suficientemente estudada. Decidimos que as características distintivas dos fatores hidroquímicos e hidrobiológicos na formação de sapropelas dos lagos estudados serão refletidas na estabilidade térmica dos ácidos húmicos extraídos dos mesmos. Análises térmicas de ácidos húmicos extraídos das camadas superiores de sedimentos de fundo dos lagos do distrito de Kondinsk, distrito de Okrug e autônomo de Khanty-Mansi, na região de Novosibirsk, usando análise térmica síncrona moderna, resultaram no artigo. De acordo com os dados obtidos, observa-se que com o aumento da temperatura máxima do efeito térmico, o valor de Z diminui (a razão da perda de massa no espaço de baixa temperatura para a perda de massa no espaço de alta temperatura), o que indica o aumento da estabilidade térmica, formação de ácidos húmicos. O indicador de ácidos húmicos de sapropels dos lagos de Kondinsk varia de 0,56 a 0,67, e estes intervalos são muito mais largos de 0,45 a 0,75 nos lagos de Barabinsk. De acordo com a análise termogravimétrica, a única declaração de alterações na estrutura química é possível, e a direção do processo pode ser assumida levando em conta os dados da química estrutural em combinação com outros métodos de análise espectral e química

Residual activity of α-chymotrypsin in water-1,2-propanediol mixtures

© 2017 Nova Science Publishers, Inc. All rights reserved.A novel experimental method was proposed to study the stability of enzymes in water-organic mixtures. This method is based on the analysis of the residual enzyme activity. Advantages of our method: (I) The residual activity curves can be determined in the entire range of the water content in organic liquids. (II) Enzyme activity values are measured at fixed reaction conditions. (III) Information on the changes in the state of the catalytically active site can be obtained separately from the other contributions (for example, changes in the solvation of the reagents and products in various water - organic mixtures). To show the efficiency of the proposed method we studied the residual activity of bovine pancreatic α-chymotrypsin (CT) in water-1,2- propanediol mixtures in the entire range of water content at 25°C. The obtained results show that the degree of stabilization/ destabilization of α- chymotrypsin depends strongly on the water content in organic solvent. (1) At high water content, the residual activity values are higher than 100%. (2) At low water content, the residual catalytic activity is~90-95%, compared with that observed after incubation in pure water. (3) A minimum on the residual activity curve was observed at intermediate water content

Hydration of proteins: Excess partial volumes of water and proteins

High precision densitometry was applied to study the hydration of proteins. The hydration process was analyzed by the simultaneous monitoring of the excess partial volumes of water and the proteins in the entire range of water content. Five unrelated proteins (lysozyme, chymotrypsinogen A, ovalbumin, human serum albumin, and β-lactoglobulin) were used as models. The obtained data were compared with the excess partial enthalpies of water and the proteins. It was shown that the excess partial quantities are very sensitive to the changes in the state of water and proteins. At the lowest water weight fractions (w 1), the changes of the excess functions can mainly be attributed to water addition. A transition from the glassy to the flexible state of the proteins is accompanied by significant changes in the excess partial quantities of water and the proteins. This transition appears at a water weight fraction of 0.06 when charged groups of proteins are covered. Excess partial quantities reach their fully hydrated values at w1 > 0.5 when coverage of both polar and weakly interacting surface elements is complete. At the highest water contents, water addition has no significant effect on the excess quantities. At w1 > 0.5, changes in the excess functions can solely be attributed to changes in the state of the proteins. © 2012 American Chemical Society

Effect of tetrahydrofuran on the binding of the competitive inhibitor proflavin and the storage stability of bovine pancreatic α-chymotrypsin

The binding of the competitive inhibitor proflavin by bovine pancreatic α-chymotrypsin in water-tetrahydrofuran mixtures was studied in the entire range of thermodynamic water activities at 25°C. The data on the binding of proflavin were compared with the results on the storage stability of α-chymotrypsin in water-organic mixtures. An analysis of the concentration dependency of these characteristics demonstrated that, at low water activity values, the interprotein contacts in the enzyme formed during its drying largely govern its functional properties, while at high water activity, they are determined by the interaction of the enzyme with the organic solvent. The interplay of these two factors is responsible for the complex shape observed for the isotherm of binding of proflavin, with a maximum degree of binding being attained at medium water activity values. © 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

Mutations in human genes that increase the risk for severe influenza infection

The system of genetic control of innate immune responses to influenza infection and gene function allows for the development of systemic treatment of influenza with a focus on the phenotype of mutations based on individual genetic susceptibility to severe disease and/or the development of complications.The system of genetic control of innate immune responses to influenza infection and gene function allows for the development of systemic treatment of influenza with a focus on the phenotype of mutations based on individual genetic susceptibility to severe disease and/or the development of complications

Chemical vapor deposition of 2D crystallized g‑C3N4 layered films

We have developed a technology and for the first time, present here, the fabrication of continuous two-dimensionally crystallized g-C3N4 layered thin films oriented in a hexagonal lattice c-plane on glass and monocrystalline silicon substrates using chemical vapor deposition from a melamine source. Scanning electron microscopy and X-ray diffraction studies revealed that such films with a smooth surface and good crystalline quality as thick as up to 1.2 μm can be formed at a synthesis temperature of 550–625 °C. They are transparent in the visible range and demonstrate intense photoluminescence (PL) at room temperature. It was found that the band gap of the obtained material and its PL spectral range are shifting to the lower energies at high synthesis temperatures. Oriented g-C3N4 layered thin films deposited on flat solid substrates are promising for integrated electronics and optoelectronics

Plasma assisted-MBE of GaN and AlN on graphene buffer layers

The possibility of using chemical vapor deposition (CVD) graphene as a 2D buffer layer for epitaxial growth of III-nitrides by plasma assisted-MBE on amorphous substrates (SiO2 prepared by thermal oxidation of Si wafer) was investigated. The comparative study of graphene-coated parts of the wafers and the parts without graphene was carried out by scanning electron microscopy and X-ray diffractometry. It was shown that epitaxial GaN and AlN films with close to 2D surface morphology can be obtained by plasma assisted-MBE on amorphous SiO2 substrates with a multilayer graphene buffer using the HT AlN nucleation layer

Experimental Substantiation of New Presentation Form of Cholera Diagnostic Sera

Objective of the study is experimental substantiation of possibility to produce new presentation form of cholera diagnostic sera – lyophilizate in bottles. Materials and methods. Cholera diagnostic sera. Liophylization was performed in Martin Christ Epsilon 2-6D. Residual moisture of dry sera was determined using humidity meter Sartorius MA 150. Solubility of experimental samples was assessed visually. pH was evaluated by potentiometry with the help of PK SevenExcellence-475 Mettler Toledo device, measuring pH/ORP/Ion content/conductivity/concentration. Specific activity and specificity was analyzed through expanded agglutination reaction, using relevant control strains of cholera vibrio. Results and conclusions. Experimentally justified is the possibility to lyophilize cholera diagnostic sera in flasks. Specified are the optimum parameters of lyophilization. It is determined that lyophilization does not result in deterioration of properties, as judging by the quality indicators they meet the requirements of regulatory documentation. Using accelerated aging test, it is demonstrated that the new presentation form of cholera diagnostic sera – lyophilizate in flasks – maintains their specific activity within five years term (the set out shelf life), which fully conform to normative standards

Production of solid dosage forms of immunoglobulin products

At the moment, there are no scientific publications devoted to the technological aspects of production of immunoglobulin solid dosage forms. The aim of the study was to review Russian and foreign literature on production of immunoglobulin solid dosage forms, and present the results of the authors’ own research. The authors analysed data of the National Register of Medicines of the Russian Federation as of mid-2021 on the authorised medicines with a generic name ‘globulin in a solid dosage form’, and summarised their characteristics. They reviewed data on the qualitative and quantitative composition of excipients used in lyophilisation, preparation of tablets and capsules. A number of examples were used to illustrate the effect of technological parameters of immunoglobulin solid form production on the quality of the finished products. It was demonstrated that the production of solid forms of immunoglobulin products prevents aggregation and fragmentation of proteins during storage, which affect the product’s specific activity, and also help to preserve the product’s target characteristics for a longer period of time as compared to liquid dosage forms of immunoglobulins. The results of the study may be used as a basis for development of a manufacturing technology for solid forms of immunoglobulin products

Experimental Substantiation of Cultural Technologies Introduction into Manufacturing of Anti-Rabies Immunoglobulin

The review provides information on the major outcomes of research and development work, performed within the frames of the Federal Target Program “National system of chemical and biological safety” (2009-2014), aimed at elaboration and introduction of cultural techniques into the manufacturing of anti-rabies immunoglobulin. Described are the key phases in methodology engineering, deployed for the large-scale cultivation of fixed rabies virus, concentration of cultural liquid, quantitation of rabies virus using PCR, and immunization of producers. Obtained pilot batches of the enhanced anti-rabies immunoglobulin, complying with normative requirements to commercial formulations, testify to the effectiveness of the developed biotechnological and methodological procedures, as well as of the designed engineering-manufacturing project documentation