Effects of γ-valerolactone in hydrolysis of lignocellulosic biomass to monosaccharides

The use of γ-valerolactone as solvent for acid-catalyzed biomass hydrolysis reactions increases reaction rates compared to reactions carried out in water.

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Heterogeneous Acid-Catalyzed Hydrolysis of Cellulose

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.512-515.421 ◽

2012 ◽

Vol 512-515 ◽

pp. 421-425

Author(s):

Jia Xin Liu ◽

Yu Dong Huang

Keyword(s):

Fossil Fuel ◽

Solid Acid ◽

Cellulosic Biomass ◽

Biomass Hydrolysis ◽

Key Technology ◽

Selective Transformation ◽

Hydrolysis Of Cellulose ◽

Acid Catalyzed ◽

Effective Use ◽

Hydrolysis Of

With the world’s focus on reducing our dependency on fossil fuel resources, one of the challenges will be the development of efficient catalysts for selective transformation of cellulosic biomass. Hydrolysis of cellulose to glucose is a key technology for effective use of lignocellulose because glucose can be efficiently converted into various chemicals, biofuels, foods, and medicines. Thus far, substantial efforts have been devoted to the degradation of cellulose but these processes have significant drawbacks. Some of these problems can potentially be overcome with the application of solid acid catalysts. In this paper, recent studies on heterogeneous acid-catalyzed hydrolysis of cellulose are summarized.

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A Thermostable Aspergillus fumigatus GH7 Endoglucanase Over-Expressed in Pichia pastoris Stimulates Lignocellulosic Biomass Hydrolysis

International Journal of Molecular Sciences ◽

10.3390/ijms20092261 ◽

2019 ◽

Vol 20 (9) ◽

pp. 2261 ◽

Cited By ~ 7

Author(s):

Aline Vianna Bernardi ◽

Deborah Kimie Yonamine ◽

Sergio Akira Uyemura ◽

Taisa Magnani Dinamarco

Keyword(s):

Pichia Pastoris ◽

Aspergillus Fumigatus ◽

Lignocellulosic Biomass ◽

Renewable Energy Sources ◽

Industrial Applications ◽

The Novel ◽

Biomass Hydrolysis ◽

Ph Range ◽

Hydrolysis Of

In the context of avoiding the use of non-renewable energy sources, employing lignocellulosic biomass for ethanol production remains a challenge. Cellulases play an important role in this scenario: they are some of the most important industrial enzymes that can hydrolyze lignocellulose. This study aims to improve on the characterization of a thermostable Aspergillus fumigatus endo-1,4-β-glucanase GH7 (Af-EGL7). To this end, Af-EGL7 was successfully expressed in Pichia pastoris X-33. The kinetic parameters Km and Vmax were estimated and suggested a robust enzyme. The recombinant protein was highly stable within an extreme pH range (3.0–8.0) and was highly thermostable at 55 °C for 72 h. Low Cu2+ concentrations (0.1–1.0 mM) stimulated Af-EGL7 activity up to 117%. Af-EGL7 was tolerant to inhibition by products, such as glucose and cellobiose. Glucose at 50 mM did not inhibit Af-EGL7 activity, whereas 50 mM cellobiose inhibited Af-EGL7 activity by just 35%. Additionally, the Celluclast® 1.5L cocktail supplemented with Af-EGL7 provided improved hydrolysis of sugarcane bagasse “in natura”, sugarcane exploded bagasse (SEB), corncob, rice straw, and bean straw. In conclusion, the novel characterization of Af-EGL7 conducted in this study highlights the extraordinary properties that make Af-EGL7 a promising candidate for industrial applications.

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Acid-Catalyzed Hydrolysis of Lignocellulosic Biomass in Ionic Liquids for Ethanol Production: Opportunities & Challenges

BioResources ◽

10.15376/biores.11.1.3-5 ◽

2015 ◽

Vol 11 (1) ◽

Author(s):

Shengdong Zhu ◽

Ke Wang ◽

Wenjing Huang ◽

Wangxiang Huang ◽

Bo Cheng ◽

...

Keyword(s):

Ionic Liquids ◽

Ethanol Production ◽

Lignocellulosic Biomass ◽

Acid Catalyzed ◽

Hydrolysis Of

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KINETIC AND ENZYME RECYCLING STUDIES OF IMMOBILIZED b-GLUCOSIDASE FOR LIGNOCELLULOSIC BIOMASS HYDROLYSIS

Environmental Engineering and Management Journal ◽

10.30638/eemj.2018.137 ◽

2018 ◽

Vol 17 (6) ◽

pp. 1385-1398 ◽

Cited By ~ 2

Author(s):

Deepak K. Tuli ◽

Ruchi Agrawal ◽

Alok Satlewal ◽

Anshu S. Mathur ◽

Ravi P. Gupta ◽

...

Keyword(s):

Lignocellulosic Biomass ◽

Biomass Hydrolysis ◽

Enzyme Recycling

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The effect of polymeric and model imidazolium halides on the rate of hydrolysis of 4-acetoxy-3-nitrobenzoic acid

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19850845 ◽

1985 ◽

Vol 50 (4) ◽

pp. 845-853 ◽

Cited By ~ 3

Author(s):

Miloslav Šorm ◽

Miloslav Procházka ◽

Jaroslav Kálal

Keyword(s):

Catalyst Concentration ◽

Low Molecular Weight ◽

Imidazolium Chloride ◽

First Order ◽

Nitrobenzoic Acid ◽

Rate Of Hydrolysis ◽

Acid Catalyzed ◽

Hydrolysis Of ◽

Ethanol In Water ◽

Direct Attack

The course of hydrolysis of an ester, 4-acetoxy-3-nitrobenzoic acid catalyzed with poly(1-methyl-3-allylimidazolium bromide) (IIa), poly[l-methyl-3-(2-propinyl)imidazolium chloride] (IIb) and poly[l-methyl-3-(2-methacryloyloxyethyl)imidazolium bromide] (IIc) in a 28.5% aqueous ethanol was investigated as a function of pH and compared with low-molecular weight models, viz., l-methyl-3-alkylimidazolium bromides (the alkyl group being methyl, propyl, and hexyl, resp). Polymers IIb, IIc possessed a higher activity at pH above 9, while the models were more active at a lower pH with a maximum at pH 7.67. The catalytic activity at the higher pH is attributed to an attack by the OH- group, while at the lower pH it is assigned to a direct attack of water on the substrate. The rate of hydrolysis of 4-acetoxy-3-nitrobenzoic acid is proportional to the catalyst concentration [IIc] and proceeds as a first-order reaction. The hydrolysis depends on the composition of the solvent and was highest at 28.5% (vol.) of ethanol in water. The hydrolysis of a neutral ester, 4-nitrophenyl acetate, was not accelerated by IIc.

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Benzyl ethers of methyl α-D-glucopyranoside

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19801959 ◽

1980 ◽

Vol 45 (7) ◽

pp. 1959-1963 ◽

Cited By ~ 1

Author(s):

Dušan Joniak ◽

Božena Košíková ◽

Ludmila Kosáková

Keyword(s):

Kinetic Study ◽

Spectrophotometric Determination ◽

Reductive Cleavage ◽

Ether Bond ◽

Benzyl Ethers ◽

Acid Catalyzed ◽

Model Substances ◽

Hydrolysis Of

Methyl 4-O-(3-methoxy-4-hydroxybenzyl) and methyl 4-O-(3,5-dimethoxy-4-hydroxybenzyl)-α-D-glucopyranoside and their 6-O-isomers were prepared as model substances for the ether lignin-saccharide bond by reductive cleavage of corresponding 4,6-O-benzylidene derivatives. Kinetic study of acid-catalyzed hydrolysis of the compounds prepared was carried out by spectrophotometric determination of the benzyl alcoholic groups set free, after their reaction with quinonemonochloroimide, and it showed the low stability of the p-hydroxybenzyl ether bond.

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Cyclization and acid-catalyzed hydrolysis of O-benzoylbenzamidoximes

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19862786 ◽

1986 ◽

Vol 51 (12) ◽

pp. 2786-2797

Author(s):

František Grambal ◽

Jan Lasovský

Keyword(s):

Reaction Rate ◽

Kinetic Isotope ◽

Acid Base Equilibrium ◽

Mineral Acids ◽

Kinetics Of Formation ◽

Acid Catalyzed ◽

Ph Scale ◽

Kinetics Of ◽

Hydrolysis Of ◽

Derivatives Of

Kinetics of formation of 1,2,4-oxadiazoles from 24 substitution derivatives of O-benzoylbenzamidoxime have been studied in sulphuric acid and aqueous ethanol media. It has been found that this medium requires introduction of the Hammett H0 function instead of the pH scale beginning as low as from 0.1% solutions of mineral acids. Effects of the acid concentration, ionic strength, and temperature on the reaction rate and on the kinetic isotope effect have been followed. From these dependences and from polar effects of substituents it was concluded that along with the cyclization to 1,2,4-oxadiazoles there proceeds hydrolysis to benzamidoxime and benzoic acid. The reaction is thermodynamically controlled by the acid-base equilibrium of the O-benzylated benzamidoximes.

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