scholarly journals Disposal of wastewater polysaccharides in the manufacture of fibrous semi-finished products

2020 ◽  
Author(s):  
А.В. Канарский ◽  
Е.Р. Якубов ◽  
И.В. Кручина-Богданов ◽  
З.А. Канарская ◽  
Э.И. Семёнов ◽  
...  
Keyword(s):  
Trichoderma Reesei ◽  
Biological Treatment ◽  
Paper Industry ◽  
Xylanase Activity ◽  
Feed Additives ◽  
Fiber Sludge ◽  
Subsequent Application ◽  
Lower Protein ◽  
Reducing Substances ◽  
Hydrolysis Of

Участки подготовки древесины, промывки и отбеливания целлюлозы, а также варочный цех являются основными источниками сточных вод в целлюлозно-бумажной промышленности. Объём сточных вод тесно связан с количеством получаемой целлюлозы в каждом конкретном процессе. При этом образуется значительное количество вторичных ресурсов в виде поли- и олигосахаридов, которые присутствуют в цеховых и заводских сточных водах. Эти воды подвергаются биологической очистке с образованием ила, который не находит полноценного практического применения. Использование активного ила в качестве флокулянта приводит к необходимости аэрирования, что достаточно дорого. Использование ила в качестве кормовых добавок не представляется возможным, так как в нем накапливаются токсиканты, и кроме того, желудочно-кишечный тракт многих животных не способен переваривать осажденную клетчатку. Ил не находит применения в сельском хозяйстве, так как сильная гидратация требует трудоемких и затратных операций перевалки, транспортировки, хранения и последующего внесения в почву. Установлена целесообразность применения сточных вод производства древесной массы из щепы берёзы для приготовления питательной среды для культивирования гриба Trichoderma reesei M18. При этом, сточные воды рекомендуется подготавливать путём инверсии при pH 4,9 и упаривания в 3 раза с увеличением содержания РВ до 3,5 Показано, что на питательной среде, приготовленной из концентрированных сточных вод, гриб Trichoderma reesei M18 проявляет ферментативную целлюлолитическую и ксиланазную активности, что способствует гидролизу олигосахаридов, и, соответственно, увеличению редуцирующих веществ в питательной среде. Путём кислотной обработки гриба Trichoderma reesei M18 получен хитин-глюкан, обладающий адсорбционными свойствами по отношению к Т-2 микотоксину. При этом наибольшей истинной адсорбционной способностью по отношению к Т-2 микотоксину обладает хитин-глюкан с меньшим содержанием белка по Барнштейну и наибольшим содержанием Д-глюкозамина. Sections of wood preparation, washing and bleaching of pulp, as well as the brewhouse are the main sources of wastewater in the pulp and paper industry. The volume of wastewater is closely related to the amount of pulp produced in each specific process. In this case, a significant amount of secondary resources is formed in the form of poly and oligosaccharides, which are present in workshop and factory wastewater. These waters undergo biological treatment with the formation of sludge, which does not find full practical use. The use of activated sludge as a flocculant leads to the need for aeration, which is quite expensive. The use of sludge as feed additives is not possible, since toxicants accumulate in it, and in addition, the gastrointestinal tract of many animals is not able to digest precipitated fiber. Sludge is not used in agriculture, since strong hydration requires laborious and costly operations of transshipment, transportation, storage and subsequent application to the soil. The feasibility of using wastewater for the production of wood pulp from birch wood chips for the preparation of a nutrient medium for the cultivation of Trichoderma reesei M18 fungus has been established. At the same time, it is recommended to prepare wastewater by inversion at pH 4.9 and evaporation by 3 times with an increase in the content of PB to 3.5. It is shown that Trichoderma reesei M18 shows enzymatic cellulolytic and xylanase activity on a substratum prepared from concentrated wastewater, which contributes to the hydrolysis of oligosaccharides, and, accordingly, an increase in reducing substances in the substratum. Acid treatment of the fungus Trichoderma reesei M18 yields chitin-glucan, which has adsorption properties in relation to T-2 mycotoxin. At the same time, chitin-glucan with the lower protein content according to Barnstein and the highest content of D-glucosamine possesses the highest true adsorption capacity in relation to T-2 mycotoxin.

scholarly journals Rational engineering of xylanase hyper-producing system in Trichoderma reesei for efficient biomass degradation

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Su Yan ◽  
Yan Xu ◽  
Xiao-Wei Yu
Keyword(s):  
Trichoderma Reesei ◽  
Xylanase Activity ◽  
High Yield ◽  
Biomass Degradation ◽  
Rational Engineering ◽  
Homologous Overexpression ◽  
Saccharification Efficiency ◽  
New Perspective ◽  
Hydrolysis Of ◽  
Xylanolytic Enzymes

Abstract Background Filamentous fungus Trichoderma reesei has been widely used as a workhorse for cellulase and xylanase productions. Xylanase has been reported as the crucial accessory enzyme in the degradation of lignocellulose for higher accessibility of cellulase. In addition, the efficient hydrolysis of xylan needs the co-work of multiple xylanolytic enzymes, which rise an increasing demand for the high yield of xylanase for efficient biomass degradation. Results In this study, a xylanase hyper-producing system in T. reesei was established by tailoring two transcription factors, XYR1 and ACE1, and homologous overexpression of the major endo-xylanase XYNII. The expressed xylanase cocktail contained 5256 U/mL xylanase activity and 9.25 U/mL β-xylosidase (pNPXase) activity. Meanwhile, the transcription level of the xylanolytic genes in the strain with XYR1 overexpressed was upregulated, which was well correlated with the amount of XYR1-binding sites. In addition, the higher expression of associated xylanolytic enzymes would result in more efficient xylan hydrolysis. Besides, 2310–3085 U/mL of xylanase activities were achieved using soluble carbon source, which was more efficient and economical than the traditional strategy of xylan induction. Unexpectedly, deletion of ace1 in C30OExyr1 did not give any improvement, which might be the result of the disturbed function of the complex formed between ACE1 and XYR1. The enzymatic hydrolysis of alkali pretreated corn stover using the crude xylanase cocktails as accessory enzymes resulted in a 36.64% increase in saccharification efficiency with the ratio of xylanase activity vs FPase activity at 500, compared to that using cellulase alone. Conclusions An efficient and economical xylanase hyper-producing platform was developed in T. reesei RUT-C30. The novel platform with outstanding ability for crude xylanase cocktail production would greatly fit in biomass degradation and give a new perspective of further engineering in T. reesei for industrial purposes.

Deinking of recycled paper by coupling of the enzyme endo-β-1,4-D-glucanasa and the cellulose, and by using a laboratory flotation column

MRS Advances ◽  
2020 ◽  
Vol 5 (52-53) ◽  
pp. 2669-2678
Author(s):  
Jeovani González P. ◽  
Ramiro Escudero G
Keyword(s):  
Amino Acids ◽  
Sodium Hydroxide ◽  
Paper Industry ◽  
Computational Simulation ◽  
Cellulose Fibers ◽  
Residual Water ◽  
Chemical Reagent ◽  
Recycled Paper ◽  
Flotation Column ◽  
Hydrolysis Of

AbstractDeinking of recycled office (MOW) paper was carried out by using a flotation column and adding separately sodium hydroxide, and the enzyme Cellulase Thricodema Sp., as defibrillators.The de-inked cellulose fibers were characterized according to the standards of the paper industry, to compare the efficiency of the deinking of each chemical reagent used to hydrolyze the fibers and defibrillate them.The computational simulation of the molecular coupling between the enzyme and cellulose was performed, to establish the enzyme-cellulose molecular complex and then to identify the principal amino-acids of endo-β-1,4-D-glucanase in this molecular link, which are responsible for the hydrolysis of the cellulose.Experimental results show the feasibility to replace sodium hydroxide with the enzyme Cellulase Thricodema Sp., by obtaining deinked cellulose with similar optical and physical properties.The use of the enzyme instead of sodium hydroxide avoids the contamination of the residual water; in addition to that, the column is operated more easily, taking into consideration that the pH of the system goes from alkaline to neutral.

scholarly journals Nutritional impact of partial or complete replacement of clover hay by untreated or biologically treated rice straw and corn stalks on: 1. growth performance and economic evaluation of growing New Zealand (NZW) White rabbits

2019 ◽  
Vol 43 (1) ◽  
Author(s):  
Hamed A. A. Omer ◽  
Sawsan M. Ahmed ◽  
Roshdy I. El-Kady ◽  
Aly A. El-Shahat ◽  
Mahmoud Y. El-Ayek ◽  
...  
Keyword(s):  
Organic Matter ◽  
New Zealand ◽  
Trichoderma Reesei ◽  
Rice Straw ◽  
Pleurotus Ostreatus ◽  
Biological Treatment ◽  
Neutral Detergent Fiber ◽  
Feed Conversion ◽  
Biological Treatments ◽  
Daily Gain

Abstract Background Agriculture by-products are considered a great potential value for utilization by ruminants as well as rabbits. They usually can be the maintenance and part of the production requirements. However, in developing countries, as well as in Egypt, animals suffer from shortage of feeds that are continuously increasing in costs. In general, biological treatments were shown to be the most effective and improved chemical composition of rice straw or corn stalks. Method This work aimed to investigate the possible ways of utilizing rice straws or corn stalks in rabbit feeding. The field work is designed to study the effect of biological treatment of Pleurotus ostreatus cultivated on rice straws and Trichoderma reesei cultivated on corn stalks and replacing clover hay by rice straws and corn stalks at levels of 0, 33, 66, and 100% either without or with microbes adding. Seventy-eight New Zealand White (NZW) rabbits aged 4–5 weeks (565 ± 13.57 g) were randomly divided into thirteen equal experimental groups. Results Untreated rice straws or biologically treated with Pleurotus ostreatus increased their contents of crude protein (CP) by 178.75 and 224.5% and nitrogen-free extract (NFE) by 6.30 and 24.53, respectively. Meanwhile, crude fiber (CF) content was reduced by 31.32 and 56.75%, and organic matter content was decreased by 2.81 and 5.51%, respectively, in comparison with the raw rice straws. Also, biological treatment of rice straws caused a decrease in values of neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL), and hemicellulose contents in comparison with either raw or treated rice straws. Furthermore, biological treatment with Trichoderma reesei realized a decrease in organic matter (OM), CF, NDF, and ADF and increased CP and ash contents in corn stalks. NFE content of corn stalks was decreased as a result of treatment without or with Trichoderma reesei experimental rations by 11.95% and 3.82% compared to raw corn stalks (CS). Biological treatments with fungi significantly (P < 0.05) improved average daily gain (ADG) and feed conversion. ADG and feed conversion were significantly (P < 0.05) improved when rabbits were fed diets containing rice straw (RS) compared to that fed CS. Rabbits fed diets replaced clover hay (CH) with 33% or 66% of RS or CS significantly increased ADG compared to control and that replaced 100% of both RS and CS containing rations. Levels of replacing had no significant effect on their dry matter intake (DMI) values. The highest improvement in feed conversion was recorded with rabbits that received diets replaced 33% of berseem hay (BH) by RS or CS, followed by that replaced 66% of BH by RS or CS. There were significantly interactions between biological treatments (T), roughage source (S), and replacement levels (L) (T × S × L) only on ADG. The best fed conversion was realized by rabbits fed diet replaced BH with 33% of RS that are treated by Pleurotus ostreatus (4.05 g DMI/g gain). Rabbits fed 33% biologically treated rice straw with Pleurotus ostreatus showed the highest economic efficiency (179%) followed by rabbits that received 33% of both rice straws treated without Pleurotus ostreatus and rabbits that received corn stalks biologically treated with Trichoderma reesei (161%). Conclusion Biological treatments of rice straws by Pleurotus ostreatus or corn stalks by Trichoderma reesei were safe, and it improves their chemical analysis and improved both daily gain and feed conversion, decreasing the costing of diet formulation which consequently decreased the price of 1-kg live body weight.

scholarly journals Processive action of cellobiohydrolase Cel7A from Trichoderma reesei is revealed as ‘burst’ kinetics on fluorescent polymeric model substrates

2005 ◽  
Vol 385 (2) ◽  
pp. 527-535 ◽  
Author(s):  
Kalle KIPPER ◽  
Priit VÄLJAMÄE ◽  
Gunnar JOHANSSON
Keyword(s):  
Bacterial Cellulose ◽  
Trichoderma Reesei ◽  
Anthranilic Acid ◽  
Degree Of Polymerization ◽  
Cellulose Substrates ◽  
Quantitative Monitoring ◽  
End Groups ◽  
Alternative Means ◽  
Burst Kinetics ◽  
Hydrolysis Of

Reaction conditions for the reducing-end-specific derivatization of cellulose substrates with the fluorogenic compound, anthranilic acid, have been established. Hydrolysis of fluorescence-labelled celluloses by cellobiohydrolase Cel7A from Trichoderma reesei was consistent with the active-site titration kinetics (burst kinetics), which allowed the quantification of the processivity of the enzyme. The processivity values of 88±10, 42±10 and 34±2.0 cellobiose units were found for Cel7A acting on labelled bacterial cellulose, bacterial microcrystalline cellulose and endoglucanase-pretreated bacterial cellulose respectively. The anthranilic acid derivatization also provides an alternative means for estimating the average degree of polymerization of cellulose and, furthermore, allows the quantitative monitoring of the production of reducing end groups on solid cellulose on hydrolysis by cellulases. Hydrolysis of bacterial cellulose by cellulases from T. reesei revealed that, by contrast with endoglucanase Cel5A, neither cellobiohydrolases Cel7A nor Cel6A produced detectable amounts of new reducing end groups on residual cellulose.

scholarly journals New methods of acid hydrolysis of cellulose and plant raw materials

2021 ◽  
Vol 57 (1) ◽  
pp. 119-128
Author(s):  
V. S. Boltovsky
Keyword(s):  
Acid Hydrolysis ◽  
Plant Biomass ◽  
Raw Materials ◽  
Agricultural Waste ◽  
Feed Additives ◽  
Process Conditions ◽  
Catalytic Systems ◽  
Plant Raw Materials ◽  
Hydrolysis Of Cellulose ◽  
Hydrolysis Of

Prospects for the development of hydrolysis production are determined by the relevance of industrial use of plant biomass to replace the declining reserves of fossil organic raw materials and increasing demand for ethanol, especially for its use as automobile fuel, protein-containing feed additives that compensate for protein deficiency in feed production, and other products. Based on the review of the research results presented in the scientific literature, the analysis of modern methods of liquid-phase acid hydrolysis of cellulose and various types of plant raw materials, including those that differ from traditional ones, is performed. The main directions of increasing its efficiency through the use of new catalytic systems and process conditions are identified. It is shown that the most promising methods for obtaining monosaccharides in hydrolytic processing of cellulose and microcrystalline cellulose, pentosan-containing agricultural waste and wood, are methods for carrying out the process at elevated and supercritical temperatures (high-temperature hydrolysis), the use of new types of solid-acid catalysts and ionic liquids. 

scholarly journals On-site integrated production of cellulases and β-glucosidases by Trichoderma reesei Rut C30 using steam-pretreated sugarcane bagasse

2018 ◽  
Author(s):  
Marcella Fernandes de Souza ◽  
Elba Pinto da Silva Bon ◽  
Ayla Sant’ Ana da Silvab
Keyword(s):  
Carbon Source ◽  
Lignocellulosic Biomass ◽  
Trichoderma Reesei ◽  
Sugarcane Bagasse ◽  
Enzyme Preparation ◽  
Integrated Approach ◽  
Aspergillus Awamori ◽  
Pretreated Sugarcane Bagasse ◽  
Hydrolysis Of ◽  
Rut C30

AbstractThe high cost of commercial cellulases still hampers the economic competitiveness of the production of fuels and chemicals from lignocellulosic biomasses. This cost may be decreased by the on-site production of cellulases with the integrated use of the lignocellulosic biomass as carbon source. This integrated approach was evaluated in the present study whereby steam-pretreated sugarcane bagasse (SPSB) was used as carbon source for the production of cellulases by Trichoderma reesei Rut C30 and the produced enzymes were subsequently used for SPSB hydrolysis. An enzyme preparation with a high cellulase activity, of 1.93 FPU/mL, was obtained, and a significant β-glucosidase activity was achieved in buffered media, indicating the importance of pH control during enzyme production. The hydrolysis of SPSB with the laboratory-made mixture resulted in a glucose yield of 80%, which was equivalent to those observed for control experiments using commercial enzymes. Even though the supplementation of this mixture with external β-glucosidase from Aspergillus awamori was found to increase the initial hydrolysis rates, it had no impact on the final hydrolysis yield. It was shown that SPSB is a promising carbon source for the production of cellulases and β-glucosidases by T. reesei Rut C30 and that the enzyme preparation obtained is effective for the hydrolysis of SPSB, supporting the on-site integrated approach to decrease the cost of the enzymatic hydrolysis of lignocellulosic biomass.

scholarly journals Production of Recombinant Trichoderma reesei Cellobiohydrolase II in a New Expression System Based on Wickerhamomyces anomalus

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Dennis J. Díaz-Rincón ◽  
Ivonne Duque ◽  
Erika Osorio ◽  
Alexander Rodríguez-López ◽  
Angela Espejo-Mojica ◽  
...  
Keyword(s):  
Trichoderma Reesei ◽  
Recombinant Expression ◽  
Expression System ◽  
Enzymatic Extract ◽  
Native Strain ◽  
Wickerhamomyces Anomalus ◽  
Optimum Ph ◽  
Hydrolysis Of Cellulose ◽  
Cellobiohydrolase Ii ◽  
Hydrolysis Of

Cellulase is a family of at least three groups of enzymes that participate in the sequential hydrolysis of cellulose. Recombinant expression of cellulases might allow reducing their production times and increasing the low proteins concentrations obtained with filamentous fungi. In this study, we describe the production of Trichoderma reesei cellobiohydrolase II (CBHII) in a native strain of Wickerhamomyces anomalus. Recombinant CBHII was expressed in W. anomalus 54-A reaching enzyme activity values of up to 14.5 U L−1. The enzyme extract showed optimum pH and temperature of 5.0–6.0 and 40°C, respectively. Enzyme kinetic parameters (KM of 2.73 mM and Vmax of 23.1 µM min−1) were between the ranges of values reported for other CBHII enzymes. Finally, the results showed that an enzymatic extract of W. anomalus 54-A carrying the recombinant T. reesei CBHII allows production of reducing sugars similar to that of a crude extract from cellulolytic fungi. These results show the first report on the use of W. anomalus as a host to produce recombinant proteins. In addition, recombinant T. reesei CBHII enzyme could potentially be used in the degradation of lignocellulosic residues to produce bioethanol, based on its pH and temperature activity profile.

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