Isolation and characterization of lignins from Eucalyptus grandis Hill ex Maiden and Eucalyptus globulus Labill. by enzymatic mild acidolysis (EMAL)

Abstract Despite the growing importance of Eucalyptus wood as raw material for pulp and paper, there is a lack of knowledge on the chemistry of their macromolecular components. The present paper addresses this issue by applying the recently developed protocol for isolating enzymatic mild acidolysis lignins (EMAL) from Eucalyptus grandis, Eucalyptus globulus and the softwood species Douglas fir and white fir, which were used for comparative purposes. The structures of EMALs were investigated by quantitative 31P NMR, DFRC/31P NMR (derivatization followed by reductive cleavage followed by quantitative 31P NMR) and size exclusion chromatography (SEC). Overall, the yields of EMALs isolated from Eucalyptus were higher than those from the softwoods examined. Lignin from E. globulus was found to contain higher contents of arylglycerol-β-aryl ether structures, free phenolic hydroxyl groups and syringyl-type units than lignin from E. grandis. New insights provided by the DFRC/31P NMR revealed that up to 62.2% of arylglycerol-β-aryl ether structures in E. globulus are uncondensed, while in E. grandis the amount of such uncondensed structures was found to be lower than 48%. SEC analyses showed that lignins from E. grandis and softwoods associate in greater extension than lignin from E. globulus.

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Behavior of xylans from the Eucalyptus species. Part 2. Characterization of 4-O-methylglucuronoxylans isolated from black liquors of kraft pulping of Eucalyptus grandis and E. urophylla

Holzforschung ◽

10.1515/hf-2012-0035 ◽

2013 ◽

Vol 67 (2) ◽

pp. 123-128

Author(s):

Andréia S. Magaton ◽

Teresa Cristina F. Silva ◽

Jorge Luiz Colodette ◽

Dorila Piló-Veloso ◽

Flaviana Reis Milagres ◽

...

Keyword(s):

Average Molecular Weight ◽

Eucalyptus Grandis ◽

Kraft Pulping ◽

Raw Material ◽

Size Exclusion ◽

Eucalyptus Species ◽

Exclusion Chromatography ◽

Ft Ir ◽

Black Liquors

Abstract 4-O-methylglucuronoxylans isolated from Eucalyptus grandis and Eucalyptus urophylla kraft black liquors (KBLs) were chemically characterized by Fourier transform infrared spectroscopy (FT-IR), size exclusion chromatography (SEC), and nuclear magnetic resonance (NMR) spectroscopy. Doses of alkali charge, expressed as active alkali (AA), were 16, 17, and 18% while the sulfidity was kept at 25%. Kappa numbers of 19.1, 17.5, and 16.1 for E. grandis and 20.4, 16.8, and 15.4 for E. urophylla were obtained. At higher alkali charges, the recovery of xylans from the KBLs was lower and the degree of substitution of xylans with uronic acids decreased. The average molecular weight (Mw) of the recovered xylans was greater under conditions of mild pulping, i.e., in the case of pulps with higher kappa numbers. Mw of xylans ranged from 16.1 to 19.1 kDa for E. grandis and from 15.4 to 20.4 kDa for E. urophylla. The xylans from KBL may be useful as pulp modifying agents or as a raw material for advanced applications.

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Effect of autohydrolysis of Eucalyptus globulus wood on lignin structure. Part 1: Comparison of different lignin fractions formed during water prehydrolysis

Holzforschung ◽

10.1515/hf.2008.117 ◽

2008 ◽

Vol 62 (6) ◽

Cited By ~ 22

Author(s):

Moritz Leschinsky ◽

Gerhard Zuckerstätter ◽

Hedda K. Weber ◽

Rudolf Patt ◽

Herbert Sixta

Keyword(s):

Nmr Spectroscopy ◽

Eucalyptus Globulus ◽

Lignin Degradation ◽

Degradation Products ◽

Chemical Properties ◽

Size Exclusion ◽

Strong Increase ◽

Hydroxyl Groups ◽

Aryl Ether ◽

Wood Residue

Abstract The effect of autohydrolysis of Eucalyptus globulus wood was studied with regard to conditions applied in a prehydrolysis-kraft process on the physico-chemical properties of lignin obtained in both the wood residue and hydrolysate. As a reference, milled wood lignin (MWL) was isolated from native wood and compared to three lignin fractions formed during prehydrolysis: 1) lignin from the wood residue isolated as MWL, 2) lignin precipitated from the prehydrolysate during cooling and separated by centrifugation, and 3) lignin degradation products soluble in the prehydrolysate extracted with ethylacetate. All lignin fractions were subjected to Fourier transform infrared (FTIR) spectroscopy, methoxy group determination, elemental analysis, size exclusion chromatography and quantitative nuclear magnetic resonance (NMR) spectroscopy. The results indicate that extensive lignin degradation occurs during prehydrolysis through homolytic cleavage of the aryl-ether bonds resulting in a substantial molecular weight loss of the residual lignin in the treated wood and in the lignin fractions isolated from the prehydrolysate. The aryl-ether cleavage is coupled with a strong increase in phenolic hydroxyl groups and a decrease in aliphatic hydroxyl groups. Indication for condensation reactions were found by NMR spectroscopy.

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Methods for Separation and Characterization of Extracellular Vesicles: Results of a Worldwide Survey Performed by the ISEV Rigor and Standardization Subcommittee

Cells ◽

10.3390/cells9091955 ◽

2020 ◽

Vol 9 (9) ◽

pp. 1955 ◽

Cited By ~ 7

Author(s):

Felix Royo ◽

Clotilde Théry ◽

Juan M. Falcón-Pérez ◽

Rienk Nieuwland ◽

Kenneth W. Witwer

Keyword(s):

Extracellular Vesicles ◽

Initial Response ◽

Size Exclusion ◽

Disease Biomarkers ◽

Quality Controls ◽

Isolation And Characterization ◽

Measurement Results ◽

Exclusion Chromatography ◽

Important Objective

Research on extracellular vesicles (EVs) is growing exponentially due to an increasing appreciation of EVs as disease biomarkers and therapeutics, an expanding number of EV-containing materials under study, and application of new preparation, detection, and cargo analysis methods. Diversity of both sources and methodologies imposes challenges on the comparison of measurement results between studies and laboratories. While reference guidelines and minimal requirements for EV research have achieved the important objective of assembling community consensus, it is also essential to understand which methodologies and quality controls are currently being applied, and how usage trends are evolving. As an initial response to this need, the International Society for Extracellular Vesicles (ISEV) performed a worldwide survey in 2015 on “Techniques used for the isolation and characterization of extracellular vesicles” and published the results from this survey in 2016. In 2019, a new survey was performed to assess the changing state of the field. The questionnaire received more than 600 full or partial responses, and the present manuscript summarizes the results of this second worldwide survey. The results emphasize that separation methods such as ultracentrifugation and density gradients are still the most commonly used methods, the use of size exclusion chromatography has increased, and techniques based on tangential flow and microfluidics are now being used by more than 10% of respondents. The survey also reveals that most EV researchers still do not perform sample quality controls before or after isolation of EVs. Finally, the majority of EV researchers emphasize that separation and characterization of EVs should receive more attention.

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Formosolv Pretreatment to Fractionate Paulownia Wood Following a Biorefinery Approach: Isolation and Characterization of the Lignin Fraction

Agronomy ◽

10.3390/agronomy10081205 ◽

2020 ◽

Vol 10 (8) ◽

pp. 1205

Author(s):

Elena Domínguez ◽

Pablo G. del Río ◽

Aloia Romaní ◽

Gil Garrote ◽

Patricia Gullón ◽

...

Keyword(s):

High Performance ◽

Complete Characterization ◽

Climatic Conditions ◽

Raw Material ◽

Size Exclusion ◽

Cellulose Content ◽

Isolation And Characterization ◽

Exclusion Chromatography ◽

Face Centered ◽

Paulownia Wood

Paulownia is a rapid-growth tree with a high biomass production rate per year and low demand of water, which make it very suitable for intercropping systems, as it protects the crops from adverse climatic conditions, benefiting the harvest yields. Moreover, these characteristics make Paulownia a suitable raw material able to be fractionated in an integrated biorefinery scheme to obtain multiple products using a cascade conversion approach. Different delignification pretreatments of biomass have been purposed as a first stage of a lignocellulosic biorefinery. In this study, the formosolv delignification of Paulownia wood was investigated using a second order face-centered factorial design to assess the effects of the independent variables (concentrations of formic and hydrochloric acids and reaction time) on the fractionation of Paulownia wood. The maximum delignification achieved in this study (78.5%) was obtained under following conditions: 60 min, and 95% and 0.05% formic and hydrochloric acid, respectively. In addition, the remained solid phases were analyzed to determine their cellulose content and cooking liquors were also chemically analyzed and characterized. Finally, the recovered lignin by precipitation from formosolv liquor and the pristine lignin (milled wood lignin) in Paulownia wood were characterized and compared by the following techniques FTIR, NMR, high-performance size-exclusion chromatography (HPSEC) and TGA. This complete characterization allowed verifying the capacity of the formosolv process to act on the lignin, causing changes in its structure, which included both phenomena of depolymerization and condensation.

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Isolation and characterization of BanLec-I, a mannoside-binding lectin from Musa paradisiac (banana)

Biochemical Journal ◽

10.1042/bj2720721 ◽

1990 ◽

Vol 272 (3) ◽

pp. 721-726 ◽

Cited By ~ 52

Author(s):

V L Koshte ◽

W van Dijk ◽

M E van der Stelt ◽

R C Aalberse

Keyword(s):

Cell Proliferation ◽

Affinity Chromatography ◽

Molecular Mass ◽

Size Exclusion ◽

T Cell Proliferation ◽

Isolation And Characterization ◽

Sds Page ◽

Exclusion Chromatography ◽

Binding Lectin

A lectin (BanLec-I) from banana (Musa paradisiac) with a binding specificity for oligomannosidic glycans of size classes higher than (Man)6GlcNAc was isolated and purified by affinity chromatography on a Sephadex G-75 column. It did not agglutinate untreated human or sheep erythrocytes, but it did agglutinate rabbit erythrocytes. BanLec-I stimulated T-cell proliferation. On size-exclusion chromatography, BanLec-I has a molecular mass of approx. 27 kDa, and on SDS/PAGE the molecular mass is approx. 13 kDa. The isoelectric point is 7.2-7.5. BanLec-I was found to be very effective as a probe in detecting glycoproteins, e.g. on nitrocellulose blots.

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The structure of the extracellular teichoic acids from the allergy-protective bacterium Lactococcus lactis G121

Biological Chemistry ◽

10.1515/hsz-2012-0142 ◽

2012 ◽

Vol 393 (8) ◽

pp. 749-755

Author(s):

Kathleen Fischer ◽

Evgueny Vinogradov ◽

Buko Lindner ◽

Holger Heine ◽

Otto Holst

Keyword(s):

Lactococcus Lactis ◽

Molecular Mechanisms ◽

Cell Envelope ◽

Teichoic Acid ◽

Size Exclusion ◽

Resonance Spectroscopy ◽

Protective Properties ◽

Isolation And Characterization ◽

Exclusion Chromatography

Abstract The Gram-positive bacterium Lactococcus lactis G121 is a farm isolate that protects mice from ovalbumin-induced asthma. To understand the molecular mechanisms of such allergy-protective properties, the isolation and characterization of cell envelope constituents is crucial. Here, structural analyses of the extracellular teichoic acid (EC TA) from L. lactis G121 are presented. Extraction with 0.9% saline afforded a crude TA fraction. Consecutive size exclusion chromatography on Biogel P60 and P10 matrix was performed to purify the sample. Chemical component analyses, high-resolution electrospray ionization Fourier-transformed ion cyclotron mass spectrometry, and nuclear magnetic resonance spectroscopy were conducted for structural elucidation. The EC TA was a poly(glycosylglycerol phosphate) molecule with a repeating unit of -6)-[β-d-Glcp-(1→3)-][α-d-GlcpNAc-(1→4)-]α-d-GalpNAc-(1→3)-β-d-GlcpNAc-(1→2)-glycerol-(1-P-).

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Fibrillar pharmacology of functionalized nanocellulose

Scientific Reports ◽

10.1038/s41598-020-79592-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sam Wong ◽

Simone Alidori ◽

Barbara P. Mello ◽

Bryan Aristega Almeida ◽

David Ulmert ◽

...

Keyword(s):

Aspect Ratio ◽

Fluorescent Dyes ◽

Pharmacokinetic Profile ◽

Water Soluble ◽

Size Exclusion ◽

Hydroxyl Groups ◽

Target Tissue ◽

Exclusion Chromatography ◽

Specific Accumulation

AbstractCellulose nanocrystals (CNC) are linear organic nanomaterials derived from an abundant naturally occurring biopolymer resource. Strategic modification of the primary and secondary hydroxyl groups on the CNC introduces amine and iodine group substitution, respectively. The amine groups (0.285 mmol of amine per gram of functionalized CNC (fCNC)) are further reacted with radiometal loaded-chelates or fluorescent dyes as tracers to evaluate the pharmacokinetic profile of the fCNC in vivo. In this way, these nanoscale macromolecules can be covalently functionalized and yield water-soluble and biocompatible fibrillar nanoplatforms for gene, drug and radionuclide delivery in vivo. Transmission electron microscopy of fCNC reveals a length of 162.4 ± 16.3 nm, diameter of 11.2 ± 1.52 nm and aspect ratio of 16.4 ± 1.94 per particle (mean ± SEM) and is confirmed using atomic force microscopy. Size exclusion chromatography of macromolecular fCNC describes a fibrillar molecular behavior as evidenced by retention times typical of late eluting small molecules and functionalized carbon nanotubes. In vivo, greater than 50% of intravenously injected radiolabeled fCNC is excreted in the urine within 1 h post administration and is consistent with the pharmacological profile observed for other rigid, high aspect ratio macromolecules. Tissue distribution of fCNC shows accumulation in kidneys, liver, and spleen (14.6 ± 6.0; 6.1 ± 2.6; and 7.7 ± 1.4% of the injected activity per gram of tissue, respectively) at 72 h post-administration. Confocal fluorescence microscopy reveals cell-specific accumulation in these target tissue sinks. In summary, our findings suggest that functionalized nanocellulose can be used as a potential drug delivery platform for the kidneys.

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