scholarly journals Simplifying levulinic acid conversion towards a sustainable biomass valorisation

2020 ◽  
Vol 22 (9) ◽  
pp. 2929-2934
Author(s):  
Chiara Defilippi ◽  
Daily Rodríguez-Padrón ◽  
Rafael Luque ◽  
Cristina Giordano
Keyword(s):  
Lignocellulosic Biomass ◽  
Levulinic Acid ◽  
High Stability ◽  
Biomass Valorisation ◽  
First Time ◽  
Hydrolysis Of

In the range of biomass valorisation, hydroconversion of levulinic acid (one of the products of the hydrolysis of lignocellulosic biomass) was tested for the first time using nanosized Ni3N and Ni0 catalysts, with very promising results alongside high stability.

scholarly journals Acid Hydrolysis of Lignocellulosic Biomass: Sugars and Furfurals Formation

Catalysts ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 437 ◽  
Author(s):  
Katarzyna Świątek ◽  
Stephanie Gaag ◽  
Andreas Klier ◽  
Andrea Kruse ◽  
Jörg Sauer ◽  
...  
Keyword(s):  
Organic Acids ◽  
Lignocellulosic Biomass ◽  
Levulinic Acid ◽  
Structural Changes ◽  
Acid Catalyst ◽  
Platform Chemicals ◽  
Continuous Plant ◽  
Biomass Sugars ◽  
Hydrolysis Conditions ◽  
Hydrolysis Of

Hydrolysis of lignocellulosic biomass is a crucial step for the production of sugars and biobased platform chemicals. Pretreatment experiments in a semi-continuous plant with diluted sulphuric acid as catalyst were carried out to measure the time-dependent formation of sugars (glucose, xylose, mannose), furfurals, and organic acids (acetic, formic, and levulinic acid) at different hydrolysis temperatures (180, 200, 220 °C) of one representative of each basic type of lignocellulose: hardwood, softwood, and grass. The addition of the acid catalyst is followed by a sharp increase in the sugar concentration. Xylose and mannose were mainly formed in the initial stages of the process, while glucose was released slowly. Increasing the reaction temperature had a positive effect on the formation of furfurals and organic acids, especially on hydroxymehtylfurfural (HMF) and levulinic acid, regardless of biomass type. In addition, large amounts of formic acid were released during the hydrolysis of miscanthus grass. Structural changes in the solid residue show a complete hydrolysis of hemicellulose at 180 °C and of cellulose at 200 °C after around 120 min reaction time. The results obtained in this study can be used for the optimisation of the hydrolysis conditions and reactor design to maximise the yields of desired products, which might be sugars or furfurals.

Research on Pretreatment Process and Product Detection in Enzymatic Hydrolysis of Lignocellulosic Biomass

2012 ◽  
Vol 503-504 ◽  
pp. 190-193
Author(s):  
Jing Jing Zhao ◽  
Hai Yan Yang ◽  
Bo Li ◽  
Fu Ming Chen
Keyword(s):  
Weight Loss ◽  
Enzymatic Hydrolysis ◽  
Lignocellulosic Biomass ◽  
Dilute Acid Pretreatment ◽  
Dilute Acid ◽  
Acid Pretreatment ◽  
Positive Correlation ◽  
Hydrolysis Yield ◽  
First Time ◽  
Hydrolysis Of

Sulfite pretreatment was explored in enzymatic hydrolysis of bagasse for the first time, and was compared with dilute acid pretreatment. The results showed that enzymatic hydrolysis yield of bagasse after sulfite treatment was lower than that of the bagasse pretreated with dilute acid. Meanwhile, complexity of sulfite pretreatment and its high cost made it infeasible for industrialized production. Results also showed positive correlation of bagasse pretreatment weight loss to enzymatic hydrolysis yield in dilute acid pretreatment processes, which made substrate weight loss a plausible parameter in pretreatment evaluation.

Recycling cellulases by pH-triggered adsorption-desorption during the enzymatic hydrolysis of lignocellulosic biomass

2014 ◽  
Vol 98 (12) ◽  
pp. 5765-5774 ◽  
Author(s):  
Yaping Shang ◽  
Rongxin Su ◽  
Renliang Huang ◽  
Yang Yang ◽  
Wei Qi ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Lignocellulosic Biomass ◽  
Adsorption Desorption ◽  
Hydrolysis Of

scholarly journals Mini-Review on the Synthesis of Furfural and Levulinic Acid from Lignocellulosic Biomass

Processes ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 1234
Author(s):  
Zhiwei Jiang ◽  
Di Hu ◽  
Zhiyue Zhao ◽  
Zixiao Yi ◽  
Zuo Chen ◽  
...  
Keyword(s):  
Reaction Mechanism ◽  
Lignocellulosic Biomass ◽  
Catalytic System ◽  
Levulinic Acid ◽  
Value Added ◽  
Environmental Issues ◽  
Alternative Route ◽  
Catalytic Systems ◽  
Renewable Biomass ◽  
Platform Chemicals

Efficient conversion of renewable biomass into value-added chemicals and biofuels is regarded as an alternative route to reduce our high dependence on fossil resources and the associated environmental issues. In this context, biomass-based furfural and levulinic acid (LA) platform chemicals are frequently utilized to synthesize various valuable chemicals and biofuels. In this review, the reaction mechanism and catalytic system developed for the generation of furfural and levulinic acid are summarized and compared. Special efforts are focused on the different catalytic systems for the synthesis of furfural and levulinic acid. The corresponding challenges and outlooks are also observed.

scholarly journals Optimisation of Recombinant Myrosinase Production in Pichia pastoris

2021 ◽  
Vol 22 (7) ◽  
pp. 3677
Author(s):  
Zuzana Rosenbergová ◽  
Kristína Kántorová ◽  
Martin Šimkovič ◽  
Albert Breier ◽  
Martin Rebroš
Keyword(s):  
Pichia Pastoris ◽  
Plant Defence ◽  
Plant Secondary Metabolites ◽  
Specific Productivity ◽  
Fermentation Conditions ◽  
Threefold Increase ◽  
Dry Cell Weight ◽  
First Time ◽  
Hydrolysis Of ◽  
Dry Cell

Myrosinase is a plant defence enzyme catalysing the hydrolysis of glucosinolates, a group of plant secondary metabolites, to a range of volatile compounds. One of the products, isothiocyanates, proved to have neuroprotective and chemo-preventive properties, making myrosinase a pharmaceutically interesting enzyme. In this work, extracellular expression of TGG1 myrosinase from Arabidopsis thaliana in the Pichia pastoris KM71H (MutS) strain was upscaled to a 3 L laboratory fermenter for the first time. Fermentation conditions (temperature and pH) were optimised, which resulted in a threefold increase in myrosinase productivity compared to unoptimised fermentation conditions. Dry cell weight increased 1.5-fold, reaching 100.5 g/L without additional glycerol feeding. Overall, a specific productivity of 4.1 U/Lmedium/h was achieved, which was 102.5-fold higher compared to flask cultivations.

Characteristics of Solid Super Acid SO42-/TiO2-Al2O3-SnO2 during Conversion of Glucose to Levulinic Acid

2012 ◽  
Vol 550-553 ◽  
pp. 103-106
Author(s):  
Ying Liu ◽  
Lu Lin ◽  
Xiao Yu Sui ◽  
Jun Ping Zhuang ◽  
Chun Sheng Pang
Keyword(s):  
Binding Energy ◽  
Levulinic Acid ◽  
Diffraction Peak ◽  
Catalyst Amount ◽  
Hydroxymethyl Furfural ◽  
Good Catalytic Activity ◽  
Super Acid ◽  
Diffraction Peaks ◽  
Acid Catalyzed ◽  
Hydrolysis Of

The effects of catalyst amount on the yields of levulinic and hydroxymethyl furfural were investigated during conversion of glucose to levulinic acid catalyzed by solid super acid SO42- / TiO2-Al2O3-SnO2. XRD and XPS were used to analyse the characteristics of solid super acid SO42- / TiO2-Al2O3-SnO2 before reaction and after reaction. The results showed that: solid super acid SO42- / TiO2-Al2O3-SnO2exhibited good catalytic activity in the reaction of hydrolysis of glucose to produce levulinic acid. There were three obvious peaks in these XRD spectra. The peaks on 44.6° and 67.1° were the characteristic diffraction peaks of γ-Al2O3. The anatase characteristic diffraction peak was on 37.4°. The catalyst was steady in the process. The binding energy of S 2p was similar to the binding energy of standard S6+ 2p in the S 2p XPS spectrum of solid super acid. O 1s XPS was double-peaked spectrum. The increase of element C was the main reason of inactivation of catalyst.

scholarly journals Biosynthesis of anandamide and N-palmitoylethanolamine by sequential actions of phospholipase A2 and lysophospholipase D

2004 ◽  
Vol 380 (3) ◽  
pp. 749-756 ◽  
Author(s):  
Yong-Xin SUN ◽  
Kazuhito TSUBOI ◽  
Yasuo OKAMOTO ◽  
Takeharu TONAI ◽  
Makoto MURAKAMI ◽  
...  
Keyword(s):  
Biosynthetic Pathway ◽  
Brain Homogenate ◽  
Wide Distribution ◽  
Rat Tissues ◽  
Lysophospholipase D ◽  
Pla2 Enzyme ◽  
First Time ◽  
Hydrolysis Of ◽  
The Brain

Anandamide (an endocannabinoid) and other bioactive long-chain NAEs (N-acylethanolamines) are formed by direct release from N-acyl-PE (N-acyl-phosphatidylethanolamine) by a PLD (phospholipase D). However, the possible presence of a two-step pathway from N-acyl-PE has also been suggested previously, which comprises (1) the hydrolysis of N-acyl-PE to N-acyl-lysoPE by PLA1/PLA2 enzyme(s) and (2) the release of NAEs from N-acyllysoPE by lysoPLD (lysophospholipase D) enzyme(s). In the present study we report for the first time the characterization of enzymes responsible for this pathway. The PLA1/PLA2 activity for N-palmitoyl-PE was found in various rat tissues, with the highest activity in the stomach. This stomach enzyme was identified as group IB sPLA2 (secretory PLA2), and its product was determined as N-acyl-1-acyl-lysoPE. Recombinant group IB, IIA and V of sPLA2s were also active with N-palmitoyl-PE, whereas group X sPLA2 and cytosolic PLA2α were inactive. In addition, we found wide distribution of lysoPLD activity generating N-palmitoylethanolamine from N-palmitoyl-lysoPE in rat tissues, with higher activities in the brain and testis. Based on several lines of enzymological evidence, the lysoPLD enzyme could be distinct from the known N-acyl-PE-hydrolysing PLD. sPLA2-IB dose dependently enhanced the production of N-palmitoylethanolamine from N-palmitoyl-PE in the brain homogenate showing the lysoPLD activity. N-Arachidonoyl-PE and N-arachidonoyl-lysoPE as anandamide precursors were also good substrates of sPLA2-IB and the lysoPLD respectively. These results suggest that the sequential actions of PLA2 and lysoPLD may constitute another biosynthetic pathway for NAEs, including anandamide.

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