scholarly journals Enhanced the Efficiency of Enzymatic Hydrolysis on Wheat Straw via Freeze-thawing Pretreatment

2021 ◽  
Author(s):  
Jianghong Sun ◽  
Yuanfang Deng ◽  
Shaohua Li ◽  
Wenyong Xu ◽  
Guoquan Liu
Keyword(s):  
Enzymatic Hydrolysis ◽  
Hydrogen Bonds ◽  
Wheat Straw ◽  
Structural Changes ◽  
Xrd Analysis ◽  
Transverse Cracks ◽  
Sem Images ◽  
Pretreatment Method ◽  
Longitudinal Cracks

Abstract This research was investigated to enhance the efficiency of enzymatic hydrolysis on wheat straw via freeze-thawing pretreatment, and to find the physicochemical structural changes after this pretreatment. Results show that, this pretreatment enhances the enzymatic hydrolysis efficiency of cellulose and hemicellulose, and hemicellulose is more susceptible to this pretreatment. The highest enzymatic hydrolysis efficiency of cellulose and hemicellulose was 57.06% and 70.66% occurred on -80℃, 24 h and -10℃, 24 h pretreated samples, with an improvement of 2.23 and 3.13 folds of control. SEM images exhibited that transverse cracks appeared before longitudinal cracks as pretreated conditions aggravated, and holes can be found on every sample after this pretreatment. FTIR and XRD analysis implied that freeze-thawing pretreatment had effect both on the crystalline and amorphous regions, and disrupted the hydrogen bonds among them. This study provided a physical pretreatment method to improve the efficiency of enzymatic hydrolysis on wheat straw.

scholarly journals Pretreatment of wheat straw leads to structural changes and improved enzymatic hydrolysis

2018 ◽  
Vol 8 (1) ◽  
Author(s):  
Qi Zheng ◽  
Tiantian Zhou ◽  
Yibin Wang ◽  
Xiaohua Cao ◽  
Songqing Wu ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Wheat Straw ◽  
Structural Changes

Pretreatment of wheat straw by supercritical CO2 and its enzymatic hydrolysis for sugar production

2010 ◽  
Vol 107 (1) ◽  
pp. 61-66 ◽  
Author(s):  
Roozbeh Alinia ◽  
Samyar Zabihi ◽  
Feridun Esmaeilzadeh ◽  
Jamshid Fathi Kalajahi
Keyword(s):  
Enzymatic Hydrolysis ◽  
Wheat Straw ◽  
Supercritical Co2 ◽  
Sugar Production

Synthesis and Characterization of Reduced Graphene Oxide

2013 ◽  
Vol 678 ◽  
pp. 56-60 ◽  
Author(s):  
Cherukutty Ramakrishnan Minitha ◽  
Ramasamy Thangavelu Rajendrakumar
Keyword(s):  
Graphene Oxide ◽  
Reduced Graphene Oxide ◽  
Graphite Oxide ◽  
High Performance ◽  
Structural Changes ◽  
Epoxy Group ◽  
Xrd Analysis ◽  
Si Substrates ◽  
Reduced Graphene ◽  
Reduced Graphite Oxide

Reduced graphene oxide is an excellent candidate for various electronic devices such as high performance gas sensors. In this work Graphene oxide was prepared by oxidizing graphite to form graphite oxide. From XRD analysis the peak around 11.5o confirmed that the oxygen was intercalated into graphite. By using hydrazine hydrate, the epoxy group in graphite oxide was reduced then the solution of reduced graphite oxide (rGO) is exfoliated. Raman spectrum of rGO contains both G band (1580 cm-1), D band (1350 cm-1). The remarkable structural changes reveals that reduction of graphene oxide from the values of ID/IG ratio that increase from 0.727 (GO) to 1.414 (rGO). The exfoliated reduced graphite oxide solution is spin coated on to the SiO2/Si substrates.

scholarly journals Effects on Lignin Redistribution in Eucalyptus globulus Fibres Pre-Treated by Steam Explosion: A Microscale Study to Cellulose Accessibility

Biomolecules ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 507
Author(s):  
Eduardo Troncoso-Ortega ◽  
Rosario del P. Castillo ◽  
Pablo Reyes-Contreras ◽  
Patricia Castaño-Rivera ◽  
Regis Teixeira Mendonça ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Eucalyptus Globulus ◽  
Steam Explosion ◽  
Laser Scanning ◽  
Structural Changes ◽  
Micro Particles ◽  
Cellulose Accessibility ◽  
Ft Ir ◽  
Enzymatic Accessibility ◽  
Physical And Chemical

The objective of this study was to investigate structural changes and lignin redistribution in Eucalyptus globulus pre-treated by steam explosion under different degrees of severity (S0), in order to evaluate their effect on cellulose accessibility by enzymatic hydrolysis. Approximately 87.7% to 98.5% of original glucans were retained in the pre-treated material. Glucose yields after the enzymatic hydrolysis of pre-treated material improved from 19.4% to 85.1% when S0 was increased from 8.53 to 10.42. One of the main reasons for the increase in glucose yield was the redistribution of lignin as micro-particles were deposited on the surface and interior of the fibre cell wall. This information was confirmed by laser scanning confocal fluorescence and FT-IR imaging; these microscopic techniques show changes in the physical and chemical characteristics of pre-treated fibres. In addition, the results allowed the construction of an explanatory model for microscale understanding of the enzymatic accessibility mechanism in the pre-treated lignocellulose.

scholarly journals Fast Dissolving Electrospun Nanofibers Fabricated from Jelly Fig Polysaccharide/Pullulan for Drug Delivery Applications

Polymers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 241
Author(s):  
Thangavel Ponrasu ◽  
Bei-Hsin Chen ◽  
Tzung-Han Chou ◽  
Jia-Jiuan Wu ◽  
Yu-Shen Cheng
Keyword(s):  
Drug Delivery ◽  
Water Vapor Permeability ◽  
Electrospun Nanofibers ◽  
Average Diameter ◽  
Xrd Analysis ◽  
Water Soluble ◽  
Vapor Permeability ◽  
Uv Spectrum ◽  
Sem Images ◽  
Triton X

The fast-dissolving drug delivery systems (FDDDSs) are developed as nanofibers using food-grade water-soluble hydrophilic biopolymers that can disintegrate fast in the oral cavity and deliver drugs. Jelly fig polysaccharide (JFP) and pullulan were blended to prepare fast-dissolving nanofiber by electrospinning. The continuous and uniform nanofibers were produced from the solution of 1% (w/w) JFP, 12% (w/w) pullulan, and 1 wt% Triton X-305. The SEM images confirmed that the prepared nanofibers exhibited uniform morphology with an average diameter of 144 ± 19 nm. The inclusion of JFP in pullulan was confirmed by TGA and FTIR studies. XRD analysis revealed that the increased crystallinity of JFP/pullulan nanofiber was observed due to the formation of intermolecular hydrogen bonds. The tensile strength and water vapor permeability of the JFP/pullulan nanofiber membrane were also enhanced considerably compared to pullulan nanofiber. The JFP/pullulan nanofibers loaded with hydrophobic model drugs like ampicillin and dexamethasone were rapidly dissolved in water within 60 s and release the encapsulants dispersive into the surrounding. The antibacterial activity, fast disintegration properties of the JFP/pullulan nanofiber were also confirmed by the zone of inhibition and UV spectrum studies. Hence, JFP/pullulan nanofibers could be a promising carrier to encapsulate hydrophobic drugs for fast-dissolving/disintegrating delivery applications.

scholarly journals Role of laccase as an enzymatic pretreatment method to improve lignocellulosic saccharification

2014 ◽  
Vol 4 (8) ◽  
pp. 2251-2259 ◽  
Author(s):  
Lucy Heap ◽  
Anthony Green ◽  
David Brown ◽  
Bart van Dongen ◽  
Nicholas Turner
Keyword(s):  
Wheat Straw ◽  
Trametes Versicolor ◽  
Enzymatic Pretreatment ◽  
Pretreatment Method ◽  
Alkaline Peroxide

The saccharification of wheat straw was improved when an incubation step was performed withTrametes versicolorlaccase (TvL) and the mediator 1-hydroxybenzotriazole (1-HBT) prior to an alkaline peroxide extraction (APE).

scholarly journals Yttrium doped phosphate-based glasses: structural and degradation analyses

2020 ◽  
Vol 6 (1) ◽  
pp. 34-49
Author(s):  
Abul Arafat ◽  
Sabrin A. Samad ◽  
Jeremy J. Titman ◽  
Andrew L. Lewis ◽  
Emma R. Barney ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Structural Changes ◽  
Xrd Analysis ◽  
Calcium Pyrophosphate ◽  
Ion Release ◽  
Subsequent Increase ◽  
Structural Characterisation ◽  
Release Studies ◽  
Degradation Properties

AbstractThis study investigates the role of yttrium in phosphate-based glasses in the system 45(P2O5)–25(CaO)– (30-x)(Na2O)–x(Y2O3) (0≤x≤5) prepared via melt quenching and focuses on their structural characterisation and degradation properties. The structural analyses were performed using a combination of solid-state nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). 31P NMR analysis showed that depolymerisation of the phosphate network occurred which increased with Y2O3 content as metaphosphate units (Q2) decreased with subsequent increase in pyrophosphate species (Q1). The NMR results correlated well with structural changes observed via FTIR and XPS analyses. XRD analysis of crystallised glass samples revealed the presence of calcium pyrophosphate (Ca2P2O7) and sodium metaphosphate (NaPO3) phases for all the glass formulations explored. Yttrium-containing phases were found for the formulations containing 3 and 5 mol% Y2O3. Degradation analyses performed in Phosphate buffer saline (PBS) and Milli-Q water revealed significantly reduced rates with addition of Y2O3 content. This decrease was attributed to the formation of Y-O-P bonds where the octahedral structure of yttrium (YO6) cross-linked phosphate chains, subsequently leading to an increase in chemical durability of the glasses. The ion release studies also showed good correlation with the degradation profiles.

Immunization efficacy of ozone-exposed cercariae against subsequent Schistosoma mansoni challenge infection

2011 ◽  
Vol 61 (3) ◽  
pp. 289-301
Author(s):  
Azza H. Mohamed
Keyword(s):  
Schistosoma Mansoni ◽  
Worm Burden ◽  
Structural Changes ◽  
Relative Weight ◽  
Challenge Infection ◽  
Total Leukocyte Count ◽  
Post Challenge ◽  
Igg Antibody ◽  
Sem Images ◽  
Infected Control

AbstractCD1 mice were immunized subcutaneously with 20 ozone-exposed (70μg/ml, 1 minute exposure) Schistosoma mansoni cercariae weekly/three weeks. The efficacy of immunization was assessed 10 weeks post challenge infection by the determination of the worm burden, ova count, oogram, granuloma diameter, IgG reactions against soluble egg antigen (SEA) and tegument structural changes of recovered worms that are immunized. A reduced worm length and a reduction in worm burden were observed in the immunized group as compared to the infected not immunized group. Moreover, no ova were found in liver and intestine from the immunized mice as compared with infected control mice. Also, immunization with ozonated cercariae showed a decrement in the mean relative weight of liver and spleen. Total leukocyte count was increased in the immunized animal as compared to the infected control. The level of total IgG antibody against SEA decreased in immunized mice as compared with the infected control mice. Scanning electron microscope (SEM) images of worms recovered 10 weeks post challenge from the immunized group revealed extensive tegumental destruction. This study underlines the significant role of ozone attenuated cercariae vaccine against S. mansoni infection, which generated specific immunity with a significant level of protection.

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