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Mesoporous solids include metal oxides, silica, phosphates and other materials. They may contain various acidic and basic sites which are, in combination with metal nanoparticles, metal atoms, functional groups, etc., could be efficient multifunctional catalysts for cascade reactions. In this shot review, the most important aspects of such catalysts that furnish their catalytic activity and selectivity for cascade reactions in biomass processing discussed. A combination of one metal with another or with metal oxid...

Multi-enzymatic cascade reactions, that is, the integration of several biocatalytic transformations occurring simultaneously, offer a wide range of possibilities and new ways to synthesize products with high added value. Such systems improve biocatalytic processes by saving time and reducing waste, while being self-sufficient in terms of requirements for related factors. As a more environmentally friendly and sustainable alternative method for the production of chemicals and biological products increases in import...

Mannitol is an important raw material in the production of resins, lubricants, coatings, surfactants, explosives, cosmetics and drugs. One of the promising ways to obtain it is the catalytic conversion of inulin, a natural polyfructosan found in large quantities in some agricultural crops. In this study a Ru-containing magnetic catalyst was proposed for the process of hydrolytic hydrogenation of inulin to mannitol. Under optimal reaction conditions a high mannitol selectivity of 44.3 % was obtained 100 % conversio...

The scale of annual reproduction of cellulose-containing biomass in nature allows us to draw an unambiguous conclusion that cellulose is the only source of raw materials for the chemical and fuel industries, representing a real alternative to fossil resources and, first of all, oil. Cellulose is the main component of plant biomass. According to some estimates, almost half of the organic carbon in the biosphere is contained in cellulose. Hydrolytic hydrogenation is a special case of carbohydrate hydrogenation. With...

A new biocatalyst based on glucose oxidase immobilized on Fe3O4 magnetite nanoparticles modified with chitosan and sodium tripolyphosphate was synthesized. Magnetite nanoparticles were obtained by mixing solutions of FeCl2 and FeCl3 with ammonia while heating to a temperature of 65 ?C. To stabilize the nanoparticles and ensure the presence of amino groups on their surface, chitosan and sodium tripolyphosphate were sequentially deposited on magnetite. Immobilization of glucose oxidase on the support was carried out...

The use of magnetic nanoparticles in biocatalysis, due to their unique properties, such as controlled particle size, large surface area, and ease of separating them and the reaction mixture by applying an external magnetic field, makes it possible to reuse enzymes immobilized on magnetic nanoparticles for catalytic processes. In this work, horseradish root peroxidase was immobilized on Fe3O4 magnetic nanoparticles. The carrier surface was modified and activated before enzyme immobilization using 3- aminopropyltrie...

The immobilization of glucose oxidase (GOx, enzyme of oxidoreductases class) was carried out on non-magnetic (SiO2, Al2O3) and magnetic mesoporous oxides (Fe3O4-SiO2, Fe3O4-Al2O3). Magnetic supports were synthesized by in-situ crystallization of magnetite nanoparticles in mesopores. The surface of the support was preliminarily modified with amino groups and the glutaraldehyde was used as a linker for covalent binding of the enzyme. The supports and biocatalysts were fully characterized using a combination of physi...

Porous supports including oxides and polymers have been employed for enzyme immobilization for many years. In recent times, the research focus has been placed on hierarchical structures, dependencies on pore sizes, and the use of magnetic porous oxides for magnetic recovery. The presence of pores or cavities where enzymes could locate to create an optimal degree of crowding achieved in cells is not a prerequisite, but it could significantly enhance the catalytic activity of biocatalysts. For the last five years, t...

In this research work, we examined the types and nature of bonds that are formed upon immobilization of peroxidase on three types of carriers: SiO2, Al2O3, Fe3O4. To solve this problem, the method of FTIR spectroscopy was used. As a result of the analysis, many spectra were obtained at all stages of enzyme immobilization. Analyzing the spectra of pure carriers and the spectra obtained after modification of the carriers,it can be said that polystyrene sulfonic acid does not form any chemical bonds with the carriers...

As a result of joint research of employees of the All-Russian Research Institute of Reclaimed Lands and Tver State Technical University, aerobic-anaerobic solid-phase fermentation of a mixture of organic animal waste and hard-to-hydrolyze raw materials of plant origin was developed. Biotransformation of the fermented mixture takes place over several days, and the pasteurization effect is achieved as a result of short-term processing of the fermentation product with ultrasound intensity of 50-60 W/sq.cm. Liquid ani...

N-methyl-D-glucose amine is an amine formed by reduction of glucosylamine or glucose oxime. N-alkylated glucamines are prepared from D-glucose and relevant alkylamines. Here synthesis of N-methyl-D-glucose amine by consecutive condensation of D-glucose with methylamine in ethanol media followed by reduction over Ni containing hyper crosslinked polystyrene is reported. In typical synthesis 50 g sample of D-glucose monohydrate was added to 150 ml of ethanol (96 wt.%) and stirred under 600 rpm for 30 minutes. Suspens...

Suzuki cross-coupling reaction is one of the most widely used and environmentally friendly methods of carbon-carbon bond formation for the synthesis of various chemicals including APIs, crop protection agents, and polymers. In this work, the Suzuki cross-coupling of 4-bromoanisole and phenylboronic acid was carried out as at ambient pressure (nitrogen atmosphere was used) while using EtOH/water mixture as a solvent at mild reaction conditions (60oC, NaOH) and at the absence of phase transfer agents. It was shown t...

Levulinic acid (LA) is a substance, which can be obtained from cellulosic biomass via acid hydrolysis. Hydrogenation of LA to gamma-valerolactone (GVL) is one of the most promising reactions in the field of biomass valorization to fine chemicals and liquid transportation fuels. Potentially, GVL obtained from lignocellulosic biomass is a versatile intermediate for the production of fuel additives and chemicals. Due to the high demand for GVL, its efficient production is currently a topic of intensive research. This...

This paper presents the results of the study of Kraft lignin hydrogenolysis process, using 5%Pd/C. The catalyst was investigated using the following physico-chemical methods: X-ray photoelectron spectroscopy, infrared spectroscopy of diffuse reflection of the adsorption of CO (DRIEFT), transmission electron microscopy, thermal gravimetric analysis, differential scanning calorimetry, the low-temperature nitrogen adsorption. Among the products obtained during hydrogenolysis of lignin the most promising for fuels are...

Last years the use of sub- and supercritical fluids in the catalyst synthesis is a great attention. Because of the unique properties subcritical water allow synthesizing the metal-based catalysts with the desired size, dispersity, structure and morphology of the active phase. In this work, we report the study of the structure of polymer-based Pdcontaining catalysts synthesized by hydrothermal deposition. It is shown that the use of palladium chloride as a metal precursor decreases significantly the specific surfac...

Here, we developed an effective D-glucose oxidation with magnetically recoverable biocatalysts. These biocatalysts were synthesized on magnetite particles obtained by different methods, polyol and co-precipitation. These MPs were coated with a layer of silica modified with amino groups. The GOx covalent attachment has been carried out via the reaction with glutaraldehyde. We established that the method of MPs synthesis affect the enzyme catalytic activity. It should be noted that the magnetically recoverable bioca...

Here, we developed an effective D-glucose oxidation with magnetically recoverable biocatalysts. These biocatalysts were synthesized on magnetite particles obtained by different methods, polyol and co-precipitation. These MPs were coated with a layer of silica modified with amino groups. The GOx covalent attachment has been carried out via the reaction with glutaraldehyde. We established that the method of MPs synthesis affect the enzyme catalytic activity. It should be noted that the magnetically recoverable bioca...

Conversion of vegetable oils and fats are of the great attention in the last decades. The main processes used in the triglyceride processing are transesterification, hydrolysis, hydrodeoxygenation, and hydrogenation. The last two reactions can be concerned with hydrotreatment processes, allowing the formation of hydrocarbons, fatty alcohols, and fatty aldehydes. These compounds can be used as fuel components, intermediated for the synthesis of surfactants, fragrances, pharmaceutical etc. In the current work, the s...

The magnetically recoverable biocatalyst was developed. The catalyst support is based on magnetite particles (MPs) composed of magnetite particles and coated with the amino terminated silica layer to facilitate further functionalization. This functionalization involves the attachment of the glutaraldehyde linker followed by the covalent attachment of horseradish peroxidase (HRP) via its amino groups. The catalyst was tested in the reaction of 2,3,6-trimethylphenol (TMP) oxidation to 2,3,5-trimethylhydrochinone (TM...

The magnetically recoverable biocatalyst was developed. The catalyst support is based on magnetite particles (MPs) composed of magnetite particles and coated with the amino terminated silica layer to facilitate further functionalization. This functionalization involves the attachment of the glutaraldehyde linker followed by the covalent attachment of horseradish peroxidase (HRP) via its amino groups. The catalyst was tested in the reaction of 2,3,6-trimethylphenol (TMP) oxidation to 2,3,5-trimethylhydrochinone (TM...