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Received: February 8th, 2021 ; Accepted: April 24th, 2021 ; Published: April 30th, 2021 ; Correspondence: grigory.slesarev@urfu.ru We compared different extraction methods for isolation of isoflavones from soybean molasses. Since conventional extraction methods are time-consuming, expensive and unsustainable, we have compared them with the NADES extraction method, which does not have these disadvantages. Fermentation-assisted technique and extraction with Natural Deep Eutectic Solvents (NADES) were compared to the conventional extraction methods. Based on the results obtained, we selected the optimal technique for isoflavones isolation. Isoflavones were identified by gas chromatography equipped with mass spectrometer (GC-MS), whereas their quantities were determined using high performance liquid chromatography (HPLC). In vivo metabolism of daidzein to S-equol was performed in rats with quantification of a yield of S-equol as a result of daidzein in vivo conversion in rats’ intestines.

Тамбасова Дарья Павловна, инженер-исследователь лаборатории органического синтеза инновационного центра химико-фармацевтических технологий, Химико-технологический институт, Уральский федеральный университет (г. Екатеринбург), d.p.tambasova@urfu.ru Любякина Полина Николаевна, аспирант кафедры «Технологии органического синтеза», Химико-технологический институт, Уральский федеральный университет (г. Екатеринбург), lubiakina.polina@urfu.ru Антонов Денис Олегович, аспирант кафедры «Технологии органического синтеза», Химико-технологический институт, Уральский федеральный университет (г. Екатеринбург), d.o.antonov@urfu.ru Ковалева Елена Германовна, кандидат химических наук, профессор кафедры Технологии органического синтеза, Химико-технологический институт, Уральский федеральный университет (г. Екатеринбург), e.g.kovaleva@urfu.ru Daria P. Tambasova, Research Engineer of the Laboratory of Organic Synthesis of the Innovation Center for Chemical and Pharmaceutical Technologies, Institute of Chemical Engineering, Ural Federal University, Yekaterinburg, d.p.tambasova@urfu.ru Polina N. Lyubyakina, Post-graduate student of the Department of Organic Synthesis Technolo-gies, Institute of Chemical Engineering, Ural Federal, Yekaterinburg, lubiakina.polina@urfu.ru Denis O. Antonov, Post-graduate student of the Department of Organic Synthesis Technologies, Institute of Chemical Engineering, Ural Federal, Yekaterinburg, d.o.antonov@urfu.ru Elena G. Kovaleva, Candidate of Chemical Sciences, Professor of the Department of Organic Synthesis Technologies, Institute of Chemical Engineering, Ural Federal University, Yekaterinburg, e.g.kovaleva@urfu.ru В данной работе были получены гетерогенные катализаторы на основе порошкового γ-оксида алюминия с иммобилизованным ферментом ксиланазой и проведено исследование их каталитической активности возможности их многократного использования. Целью работы являлось создание эффективной гетерогенной каталитической системы на основе γ-оксида алюминия с иммобилизованным ферментом для разложения природного полисахарида ксилана с максимальным выходом целевого продукта. В ходе работы проводилась иммобилизация ксиланазы на γ-Al₂O₃ двумя способами, а именно, физической адсорбцией и ковалентным связыванием с использованием глутарового альдегида как сшивающего агента. Реакции ферментативного гидролиза ксилана, исследование каталитической активности и операционной стабильности иммобилизованного фермента в 4-х циклах проводились на полученных систе-мах. Образец оксида алюминия синтезирован золь-гель методом с температурой обжига 550 °С в течение 4 часов, что соответствует γфазе оксида алюминия. Заряд поверхности по-лученного образца был охарактеризован методом ЭПР pH-чувствительных нитроксильных радикалов. Установлено, что по сдвигам кривых ЭПР титрования поверхность γ-Al₂O₃ имеет положительный заряд, что подразумевает наличие центров Льюиса на поверхности. Было ус-тановлено, что каталитическая активность ксиланазы, иммобилизованной на поверхности γ-Al₂O₃ методом ковалентного присоединения через глутаровый альдегид выше, чем при им-мобилизации посредством физической адсорбции в 1,83 раза и составляет 12,23U/мг. Найдено, что, ферментативная активность ковалентно иммобилизованной ксиланазы при первых двух циклах достаточно высока, на третьем цикле она снижается до 37,5 % и выходит на плато. При иммобилизации фермента физической адсорбцией активность продолжает снижаться до 23 % в 4-м цикле. Разложение ксилана гетерогенными каталитическими системами на основе γ-Al₂O₃ и иммобилизованного на нем различными способами фермента ксиланазы, и проведение сравнительного анализа полученных данных, позволяет сделать вывод о перспективности дальнейшего использования полученных систем, например, в птицеводстве в силу эффективности применения иммобилизованной ксиланазы в высвобождении редуцирующих сахаров. In this work, heterogeneous catalysts based on powdered γ-alumina with an immobilized xylanase enzyme were obtained and a study of their catalytic activity and the possibility of their repeated use was carried out. The aim of this research work was to create an effective heterogeneous catalytic system based on γ-alumina with an immobilized enzyme for the decomposition of the natural polysaccharide xylan with the maximum yield of the target product. In the course of the work, xylanase was immobilized on γ-Al₂O₃ by two methods, namely, physical adsorption and covalent binding using glutaraldehyde as a cross-linking agent. The reactions of enzymatic hydrolysis of xylan, the study of the catalytic activity and operational stability of the immobilized enzyme in 4 cycles were carried out on the obtained systems. An alumina sample was synthesized by the sol-gel method with a temperature of calcination of 550 °C for 4 hours, which corresponds to the γ -phase of alumina. The surface charge of the obtained sample was characterized by EPR of pH-sensitive nitroxide radicals. According to the shifts of the EPR titration curves, the surface of γ-Al₂O₃ was found to have a positive charge which implies the presence of Lewis centers on its surface. The catalytic activity of xylanase immobilized on the γ-Al₂O₃ surface by the method of covalent attachment through glutaraldehyde is 1.83 times higher than in case of immobilization by physical adsorption and is equal to 12.23 U / mg. The enzymatic activity of covalently immobilized xylanase in the first two cycles was found to be quite high, in the third cycle it decreases to 37.5 % and reaches a plateau. When the enzyme is immobilized by physical adsorption, the activity continues to decrease to 23 % in the 4th cycle. The decomposition of xylan by heterogeneous catalytic systems based on γ-Al₂O₃ and the xylanase enzyme immobilized on it by various meth-ods, and a comparative analysis of the data obtained, allows us to conclude that further use of the obtained systems is promising, for example, in poultry farming due to the effectiveness of the use of immobilized xylanase in the release of reducing sugars. Статья подготовлена при финансовой поддержке гранта РФФИ по научному проекту № 18-29-12129 мк.

Phaffia rhodozyma (also known as Xanthophyllomyces dendrorhous) is one of the most promising natural sources of commercial astaxanthin. It has high growth rates, easy cultivation conditions and able to utilize different carbon substrates. This provides an opportunity to further lower production cost by using industrial waste such as molasses. This research therefore evaluates the growth dynamic and astaxanthin production of P. rhodozyma Y1654 growing on soy and sugar beet molasses-based media. Liquid growth media based on soy molasses (SM), sugar beet molasses (SBM) and glucose (control) as main sugar source with peptone and yeast extract supplementation were inoculated with 48 h old seed culture (grown in standard glucose media: 2.0% glucose, 1.0% peptone, 0.2% yeast extract) and incubated at 20 °C with stirring speed of 180 rpm for 7 days. Samples were taken daily throughout the study period to assess; cell count, dry cell weight (DCW) and amount of astaxanthin. Soy molasses-based media resulted in the highest biomass yield (7.7 g L -1 ) followed by SBM (5.8 g L -1 ). Generally, more than 90% of initial fermentable sugar was consumed at the end of the study. However, about 40% of total sugar in SM was unassimilable by P. rhodozyma Y1654. The highest astaxanthin yield was observed in the control media (77 µg g -1 of DCW). Cultivation of P. rhodozyma Y1654 in SBM resulted in as much as twice (32.8 µg g -1 of DCW) the astaxanthin yield of SM (12.4 µg g -1 DCW). Molasses-based media are good for growth of P. rhodozyma Y1654 but for astaxanthin production, they need further optimization.

Article Antioxidant evokes numerous health benefits to the consumer as well as stabilisation of the beverages flavours. Therefore, this paper provides detailed information on the application of Monascus purpureus IHEM LY2014 - 0696 in combination with vario us malts in brewing antioxidant rich beverage (ARB). Starter culture Angkak was prepared by solid state bioprocessing (SSB). Single infusion method of mashing was used. Physicochemical parameters, volatile compounds, DPPH (2, 2 - diphenyl - 1 - picrylhydrazyl) r adical scavenging activity and fermentability of the wort were evaluated. Distillation procedure based on pycnometry technique was use to quantify the alcohol content (%ABV). Fermentability of the wort was found to be 97.6 ± 0.46% whilst %ABV was equal to 5.42 ± 0.03 . It was observed that ARB showed a strong DPPH radical scavenging activity of 1.00 × 10 – 4 mol × equ (R 2 = 0.91) whereas 3.43 × 10 - 5 mol × equ (R 2 = 0.81) for wort. The strong antioxidant activity (AOA) is thought to be caused by pigments produced by M. purpureus IHEM LY2014 - 0696 and other compounds originated from the malts and hops utilised in brewing ARB. A total of 4 volatile compounds were identified in the present study. Incidence of microbial load ranged from 2.14 ± 0.04 × 10 7 and 0.8 ± 0.1 × 10 5 for M. purpureus IHEM LY2014 - 0696 and bacterial respectively was observed in the ARB. This study contradicts some previous ones, as the ARB brewed did not take the red pigment produced by the M. purpureus . Panellists generally ex pressed their acceptance for the ARB as they assessed it as a new product, moreover, taking account its health benefits.

Article In recent years, there has been a growing demand for non-traditional beer (craft) with different flavours hence the main aim of this research is to produce beer with sea buckthorns (SBT). Brewing software BeerSmith was used to design the Kölch beer. After one month of primary fermentation, SBT were sanitised and crashed before adding into the green beer. Carbonation was done using keg with 1.8 bar of carbon dioxide. Physicochemical properties, microbial load and sensory evaluation of Kölch fruit beer (KFB) were determined. All the physiochemical parameters measured were significantly (P < 0.05) influenced by the fermentation time. The pH dropped from 5.8 ± 0.1 to 3.9 ± 0.1 toward the end of the fermentation. There was no microbial growth when KFB was inoculated in the media. °Brix likewise decreases from 13.3 ± 0.43 to 3.86 ± 0.25. There was a change in the colour of the wort throughout the fermentation from 11.2 ± 0.44 to 32.5 ± 0.56 EBC. A decrease from 1.48 ± 0.02 to 0.86 ± 0.02 mg maltose per 100 ml in the reducing sugar was observed during the entire period of fermentation. A total of 32 volatile compounds were identified. All assessed sensory variables of KFB were significantly different (P < 0.05) and preferred by the panellists, however, foaminess and clarity of KFB should have to be improved. KFB showed higher DPPH radical scavenging activity as compared to other types of beer examined due to biologically active substances contributed by SBT.

The grafting of silane groups on clay surfaces has been recently investigated in order to fabricate versatile compounds with new potential applications in materials science and ecological engineering. This work explored the influence of variety of solvents with variable polarity on the silanization of halloysite nanoclay (HNT) surface by (3-Glycidyloxy propyl) trimethoxy silane. To this purpose, the functionalization of HNT by 3-Glycidyloxypropyltrimethoxysilane (GOPTMS) has been conducted in Ethanol (polar protic solvent), Tetrahydrofuran (THF) and Acetonitrile (polar aprotic solvents), and Hexane, 1,4-Dioxane and Toluene (non polar solvents). The silane grafted materials were characterized by using several techniques, including Fourier Transform Infrared Spectroscopy (FT-IR), elemental analysis, Scanning Electron Microscopy (SEM), Thermogravimetry (TGA), X-ray Diffraction Analysis (XRD) and Nitrogen adsorption/desorption isotherms. The largest silane loading has been detected for the hybrid nanomaterials prepared in Hexane as a dispersing medium. Graphic Abstract: [Figure not available: see fulltext.]

The modification of chitosan represents a challenging task in obtaining biopolymeric materials with enhanced removal capacity for heavy metals. In the present work, the adsorption characteristics of chitosan modified with carboxyl groups (CTS-CAA) towards copper (II) and zinc (II) ions have been tested. The efficacy of the synthesis of CTS-CAA has been evaluated by studying various properties of the modified chitosan. Specifically, the functionalized chitosan has been characterized by using several techniques, including thermal analyses (differential scanning calorimetry and thermogravimetry), spectroscopies (FT-IR, XRD), elemental analysis, and scanning electron microscopy. The kinetics and the adsorption isotherms of CTS-CAA towards both Cu (II) and Zn (II) have been determined in the aqueous solvent under variable pH. The obtained results have been analyzed by using different adsorption models. In addition, the experiments have been conducted at variable temperatures to explore the thermodynamics of the adsorption process. The regeneration of CTS-CAA has been investigated by studying the desorption process using different eluents. This paper reports an efficient protocol to synthesize chitosan-based material perspective as regenerative adsorbents for heavy metals. © 2022 by the authors. Licensee MDPI, Basel, Switzerland. The authors express their gratitude to Princess Nourah bint Abdulrahman University Researchers Supporting Project number (PNURSP2022R13), Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia. The work was supported by the Russian Foundation for Basic Research (RFBR) grant 18-29-12129mk. The researcher A.M. Abu El-Soad is funded by a scholarship under the Joint Executive program between the Arab Republic of Egypt and Russian Federation.

A new adsorbent, sulfated crosslinked chitosan (SGCH), has been synthesized for the effective extraction of beryllium ions from their aqueous solutions. In recent times, beryllium extraction has been of great importance because beryllium can be used in many applications such as in nuclear reactor, heat shields, high-technology ceramics, alloys and electronic heat sinks. SGCH has been synthesized by two successive phases. The first is the conversion of chitosan (CH) into non-soluble cross-linked chitosan (GCH) through the interaction between chitosan and glutaraldehyde. The second step is the formation of functional sulfonate groups onto the adsorbent material through the interaction of GCH with chlorosulfonic acid (sulfating agent). The role played by the sulfonate groups in the adsorption process was analyzed using FT-IR and SEM. Also, the role played by the solution pH, time, beryllium concentration and temperature on the batch adsorption process was investigated. Our results point to the successful preparation of SGCH adsorbent with high affinity for beryllium ions. The maximum sorption values of beryllium ions on the investigated biosorbent is 40.6 mg/g. The desorption of the loaded beryllium ions from the SGCH was achieved by using 1.5 M urea acidified by 0.6 M H2SO4.

Modified halloysite nanotubes (HNTs-Cl) were synthesized by a coupling reaction with (3-chloropropyl) trimethoxysilane (CPTMS). The incorporation of chloro-silane onto HNTs surface creates HNTs-Cl, which has great chemical activity and is considered a good candidate as an active site that reacts with other active molecules in order to create new materials with great applications in chemical engineering and nanotechnology. The value of this work lies in the fact that improving the degree of grafting of chloro-silane onto the HNT’s surface has been accomplished by incorporation of HNTs with CPTMS under different experimental conditions. Many parameters, such as the dispersing media, the molar ratio of HNTs/CPTMS/H2O, refluxing time, and the type of catalyst were studied. The greatest degree of grafting was accomplished by using toluene as a medium for the grafting process, with a molar ratio of HNTs/CPTMS/H2O of 1:1:3, and a refluxing time of 4 h. The addition of 7.169 mmol of triethylamine (Et3N) and 25.97 mmol of ammonium hydroxide (NH4OH) led to an increase in the degree of grafting of CPTMS onto the HNT’s surface. © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This research was funded by Program 211 of the Government of the Russian Federation No. 02.A03.21.0006, RFBR grants 17-03-00641 and 18-29-12129 mk, the State Task from the Ministry of the Education and Science of the Russian Federation No. 4.9514.2017/8.9.

Functionalization of halloysite nanotubes surface by using organosilanes is sensitive to the reaction conditions. Halloysite nanotubes (HNTs) were modified using (3-Mercaptopropyl) trimethoxy silane (MPTMS). The experiments were performed under different reaction conditions including, various solvents [Toluene, Tetrahydrofuran (THF), Ethanol, n-Hexane, 1,4 Dioxane and Acetonitrile], water content in the reaction media, volume of solvent, number of moles of silane and catalysts (triethyl amine, ammonia solution and tetra-ethoxy titanium). The elemental analysis, FT-IR analysis were used to identify the samples, which attained the highest percent of functionalization. SEM image and thermogravimetric analysis were provided for the pristine halloysite nanotubes and the modified halloysite nanotubes samples. This work provides a systematic investigation of the reaction conditions highlighting the best protocol to perform such a modification that represents a relevant strategy to control the surface properties of halloysite nanotubes as well as the optimization of the first step toward further modifications of this nano clay.