scholarly journals Monitoring transformation of two tropical lignocellulosics and their lignins after residence in Benin soils

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Rodrigue Daassi ◽  
Pierre Betu Kasangana ◽  
Damase P. Khasa ◽  
Tatjana Stevanovic
Keyword(s):  
Quantum Coherence ◽  
Mineral Content ◽  
Lignin Content ◽  
Gmelina Arborea ◽  
Total Carbohydrate ◽  
N Enrichment ◽  
Field Incubation ◽  
Aryl Ethers ◽  
Total Lignin ◽  
Total Lignin Content

AbstractThermally assisted Hydrolysis and Methylation (THM), and 2D-heteronuclear single quantum coherence nuclear magnetic resonance (2D HSQC NMR) spectroscopy were used to monitor the transformation of ramial chipped wood (RCW) from Gmelina arborea and Sarcocephalus latifolius, together with their organosolv lignins, following soil incubation in Benin (West Africa). Mesh litterbags containing RCW were buried in soils (10 cm depth) and were retrieved after 0, 6, 12 and 18 months of field incubation. Chemical analysis showed that total carbohydrate content decreased, while total lignin content increased as RCW decomposition progressed. Ash and mineral content of RCW increased significantly after 18 months of decomposition in soil. Significant N-enrichment of the RCW was determined following 18 months incubation in soils, reaching 2.6 and 1.9 times the initial N-content for G. arborea and S. latifolius. Results of THM showed that the S + G sum, corresponding to lignins, increased with RCW residence time in the soils, in contrast to the response of compounds derived from carbohydrates, the sum of which decreased. Remarkably, lignin interunit linkages, most notably β-O-4′ aryl ethers, β-β′ resinol, β-5′ phenylcoumaran and p-PCA p-coumarate, survived after 18 months in the soil, despite their gradual decrease over the duration of the experiment.

scholarly journals Optimization of Lignin Recovery from the Pre-Hydrolysate of Kraft-Based Dissolving Pulp Production Processes

2021 ◽  
Vol 11 (1) ◽  
pp. 454
Author(s):  
Adil Mazar ◽  
Naceur Jemaa ◽  
Waleed Wafa Al Dajani ◽  
Mariya Marinova ◽  
Michel Perrier
Keyword(s):  
Molecular Weight ◽  
Lignin Content ◽  
Sulfuric Acid Concentration ◽  
Dissolving Pulp ◽  
Potential Candidate ◽  
Lignin Extraction ◽  
Dissolved Organic Matters ◽  
Lignin Recovery ◽  
Total Lignin ◽  
Total Lignin Content

A pre-hydrolysate is an aqueous stream obtained during the production of hardwood kraft dissolving pulp. It is rich in sugars and contains dissolved organic matters. The purpose of this study is to investigate the optimization of lignin recovery from wood pre-hydrolysates and to characterize the extracted lignin. The optimal conditions for lignin extraction have been determined to be (a) a filtration temperature of 40 °C, (b) a sulfuric acid concentration of 8.5 kg·m−3, and (c) a coagulation time of 180 min. Using these conditions, high filtration rates have been obtained and the extracted lignin has a low content of impurities (8.3%), a low molecular weight (1270 Da), and a very low polydispersity (Mw/Mn = 1.22). Compared to kraft lignin, the pre-hydrolysate lignin has a much lower molecular weight and could be a potential candidate for niche applications. A high lignin recovery rate is possible (52% of the total lignin content in the pre-hydrolysate).

scholarly journals Hypolignification: A Decisive Factor in the Development of Hyperhydricity

Plants ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 2625
Author(s):  
Nurashikin Kemat ◽  
Richard G. F. Visser ◽  
Frans A. Krens
Keyword(s):  
Cell Wall ◽  
Lignin Content ◽  
Coumaric Acid ◽  
Wild Type ◽  
Higher Plant ◽  
Gene Coding ◽  
Phenylpropanoid Biosynthesis ◽  
Total Lignin ◽  
Total Lignin Content

One of the characteristics of hyperhydric plants is the reduction of cell wall lignification (hypolignification), but how this is related to the observed abnormalities of hyperhydricity (HH), is still unclear. Lignin is hydrophobic, and we speculate that a reduction in lignin levels leads to more capillary action of the cell wall and consequently to more water in the apoplast. p-coumaric acid is the hydroxyl derivative of cinnamic acid and a precursor for lignin and flavonoids in higher plant. In the present study, we examined the role of lignin in the development of HH in Arabidopsis thaliana by checking the wild-types (Ler and Col-0) and mutants affected in phenylpropanoid biosynthesis, in the gene coding for cinnamate 4-hydroxylase, C4H (ref3-1 and ref3-3). Exogenously applied p-coumaric acid decreased the symptoms of HH in both wild-type and less-lignin mutants. Moreover, the results revealed that exogenously applied p-coumaric acid inhibited root growth and increased the total lignin content in both wild-type and less-lignin mutants. These effects appeared to diminish the symptoms of HH and suggest an important role for lignin in HH.

scholarly journals DEFORMAÇÃO RESIDUAL LONGITUDINAL E SUA RELAÇÃO COM ALGUMAS CARACTERÍSTICAS DE CRESCIMENTO E DA MADEIRA EM CLONES DE EUCALYPTUS

FLORESTA ◽  
2003 ◽  
Vol 33 (3) ◽  
Author(s):  
Marcos Aurélio Mathias De Souza ◽  
Paulo Fernando Trugilho ◽  
José Tarcísio Lima ◽  
Sebastião Carlos Da Silva Rosado
Keyword(s):  
Tree Growth ◽  
Lignin Content ◽  
Residual Deformation ◽  
Growth Characteristics ◽  
Dry Density ◽  
Grain Angle ◽  
Cleavage Strength ◽  
Tangential Shrinkage ◽  
Total Lignin ◽  
Total Lignin Content

Os objetivos deste trabalho foram verificar a variação da deformação residual longitudinal em clones de eucaliptos e determinar a sua correlação com algumas características físicas e mecânicas da madeira e com as de crescimento da árvore. Os resultados indicam que a deformação residual longitudinal (DRL) não apresentou correlação significativa com as características de crescimento da árvore e com os teores de lignina insolúvel, solúvel e total. A DRL apresentou correlação positiva e significativa com o índice de rachamento, as densidades básica e seca, desvio da grã, contração volumétrica, radial e tangencial e resistência ao fendilhamento. LONGITUDINAL RESIDUAL DEFORMATION AND YOUR RELATIONSHIP WITH SOME CHARACTERISTICS OF GROWTH AND OF THE WOOD IN CLONES OF EUCALYPTUS Abstract This research aimed to evaluate the variation of the longitudinal residual deformation of eucalyptus clones and to determine the correlation among the longitudinal residual deformation and tree growth characteristics and with some wood characteristics. The results indicate that the longitudinal residual deformation (DRL) didn’t present significant correlation with tree growth characteristics and insoluble, soluble and total lignin content. The DRL presented positive and significant correlation with the split index, the basic and dry density, grain angle, volumetric, radial and tangential shrinkage and cleavage strength.

The influence of lignin chemistry and ultrastructure on the pulping efficiency of clonal aspen (Populus tremuloides Michx.)

Holzforschung ◽  
2006 ◽  
Vol 60 (2) ◽  
pp. 111-122 ◽  
Author(s):  
Jaclyn J. Stewart ◽  
John F. Kadla ◽  
Shawn D. Mansfield
Keyword(s):  
Populus Tremuloides ◽  
Lignin Content ◽  
Insoluble Fraction ◽  
Pulp Yield ◽  
Wood Chemistry ◽  
Structural Differences ◽  
Chemical Pulping ◽  
Degree Of Condensation ◽  
Total Lignin ◽  
Total Lignin Content

Abstract The variation in wood chemistry among aspen clones of similar age, harvested from a common site in northern British Columbia, Canada, was evaluated. The aspen clones were evaluated for ease of chemical pulping and differed by as much as 4.5% in pulp yield at a common H-factor. The results demonstrate both the need for understanding the resource and the substantial opportunities that exists in natural population of trees for selecting superior clones for reforestation and afforestation. The syringyl/guaiacyl ratio, as determined by nitrobenzene oxidation, was directly correlated with the ease of pulping, whereas thioacidolysis results were not as predictive. These results were supported by quantitative NMR analysis, which demonstrated differences in the amount of β-O-4/Ar groups and the degree of condensation. Furthermore, it was shown that, in addition to total lignin content, which differed by as much as 5%, structural differences in the lignin may influence pulping efficacy. Among the other parameters evaluated, the distribution of molecular mass and methoxyl content is relevant for pulping. More specifically, among the fractions isolated in this study [milled wood lignin (MWL), MWELsol, and MWELinsol], the insoluble fraction was the most indicative of the pulping efficiency.

The Impact of Lignin Content on Paper Physical Strength of CTMP

2011 ◽  
Vol 236-238 ◽  
pp. 1242-1245
Author(s):  
Ben Ping Lin ◽  
Bei Hai He ◽  
Guang Lei Zhao
Keyword(s):  
Lignin Content ◽  
Strength Properties ◽  
Paper Strength ◽  
Fiber Morphology ◽  
Burst Strength ◽  
Physical Strength ◽  
The Impact ◽  
Linear Correlations ◽  
Total Lignin ◽  
Total Lignin Content

The research reported here gives some new insights into the influence of lignin content on paper strength properties. The relative amount of total lignin in CTMP was varied by using multistage ClO2 bleaching method. Few differences were observed in fiber morphology charcteristics of CTMP during ClO2 treatments. Linear correlations greater than 99% were found between total lignin content and paper strength properties. The influences of lignin content on Scott bond and tensile strength were greater than that of tear and burst strength.

Simplified determination of total lignin content in kraft lignin samples and black liquors

Holzforschung ◽  
2011 ◽  
Vol 65 (4) ◽  
Author(s):  
Fredrik Aldaeus ◽  
Hannah Schweinebarth ◽  
Per Törngren ◽  
Anna Jacobs
Keyword(s):  
Acid Hydrolysis ◽  
Standard Method ◽  
Lignin Content ◽  
Kraft Lignin ◽  
Black Liquors ◽  
Total Lignin ◽  
Total Lignin Content

Abstract Determination of total lignin content in lignin samples and black liquors using methods with reduced or omitted acid hydrolysis has been compared to the standard method, and results show that the simplified methods yield equivalent results.

NMR studies on Fraser fir Abies fraseri (Pursh) Poir. lignins

Holzforschung ◽  
2005 ◽  
Vol 59 (5) ◽  
pp. 488-496 ◽  
Author(s):  
Mikhail Yu. Balakshin ◽  
Ewellyn A. Capanema ◽  
Barry Goldfarb ◽  
John Frampton ◽  
John F. Kadla
Keyword(s):  
Quantum Coherence ◽  
Lignin Content ◽  
Lower Amount ◽  
Multiple Quantum ◽  
Normal Wood ◽  
Nmr Studies ◽  
Oh Groups ◽  
Fraser Fir ◽  
Heteronuclear Multiple Quantum Coherence ◽  
Balsam Woolly Adelgid

Abstract The composition of mature, juvenile uninfested and juvenile infested Fraser fir wood (Rotholz) and the structures of lignins isolated from these woods were elucidated to verify differences between juvenile and mature wood and the effect of balsam woolly adelgid (BWA) infestation. Milled wood lignin (MWL) isolated from mature, juvenile and Rotholz wood were comprehensively characterized using heteronuclear multiple quantum coherence (HMQC) and quantitative 13C NMR techniques. The Rotholz wood was found to have ∼13% higher lignin content and more than five-fold the amount of galactans than that of the uninfested wood. Rotholz lignin possesses higher amounts of p-hydroxyphenyl units and aliphatic OH groups and a lower amount of alkyl-O-alkyl linkages and dibenzodioxocin moieties. The degree of condensation of the Rotholz lignin was rather similar to that of normal wood. Only small differences in the structure of mature and juvenile wood components were found.

Effects of Fenton oxidation on structural changes of lignin from steam-exploded poplar

BioResources ◽  
2020 ◽  
Vol 15 (3) ◽  
pp. 6181-6191
Author(s):  
Cheng Pan ◽  
Lan Yao ◽  
Haitao Yang ◽  
Lanfeng Hui ◽  
Zhong Liu
Keyword(s):  
Quantum Coherence ◽  
Structural Changes ◽  
Oxidation Process ◽  
Average Molecular Weight ◽  
Fenton Oxidation ◽  
Heteronuclear Single Quantum Coherence ◽  
Structural Units ◽  
Weight Average Molecular Weight ◽  
Fenton Oxidation Process ◽  
Total Lignin

Pretreatment of steam-exploded poplar by Fenton oxidation was used to effectively biodegrade lignin. The structure of lignin samples (LS from steam-exploded poplar and LSF from samples further treated by Fenton oxidation) obtained by enzymatic hydrolysis during pretreatment were characterized and compared. The results showed that the demethoxy reaction occurred in the process of Fenton oxidation. GPC results indicated that the weight average molecular weight (Mw) of LSF did not change significantly, indicating that that there was no significant condensation during Fenton oxidation pretreatment. Heteronuclear single quantum coherence nuclear magnetic resonance (HSQC NMR) results suggested that the proportion of the three-unit basic structural units of poplar (H, G, and S) were significantly changed during Fenton oxidation process, and more lignin S units were removed than lignin G units. The content of β-O-4 linkages was lower in LSF (74.0%, as a fraction of β-O-4 + β-5 + β-β) than in LS (78.2%), which indicated that β-O-4 linkages were destroyed to a certain extent during Fenton oxidation process, and the content of total lignin interunit linkages including β-O-4, β−β, and β-5 linkages over total lignin aromatic subunits (Ar%) in LSF was higher, reaching 49.9%.

scholarly journals Description and Cytology of a Form of Signal Grass (Brachiaria brizantha Stapf.) and its Agronomic Behavior Compared to Guinea Grass (Panicum maximum Jack.)

1969 ◽  
Vol 44 (4) ◽  
pp. 208-220
Author(s):  
A. Sotomayor-Ríos ◽  
J. Vélez-Fortuño ◽  
R. Woodbury ◽  
K. F. Schertz ◽  
A. Sierra-Bracero
Keyword(s):  
Puerto Rico ◽  
Mineral Content ◽  
Lignin Content ◽  
Panicum Maximum ◽  
Somatic Chromosome Number ◽  
Brachiaria Brizantha ◽  
Important Place ◽  
Forage Crop ◽  
Guinea Grass ◽  
Signal Grass

The somatic chromosome number of a form of Signal grass (Brachiaria brizantha Stapf.), Puerto Rico P.I. No. 1525, introduced from Ceylon, was found to be 36. Only 15 percent of the florets studied developed karyopses. The meiotic behavior of chromosomes at microsporogenesis was irregular. Frequent lagging univalents at anaphase 1 and micronuclei in the spore quartets may account for the low seed-set of this form. More improvement of this character is expected in Signal grass through further research in genetics and by the introduction of more forms and varieties. A field description of Signal grass is given. Signal grass was compared to Guinea grass (Panicum maximum Jack.) as to agronomic behavior. It showed desirable characteristics, besides yielding the same as Guinea grass, one of our best forage grasses, when both grasses were tested at the Gurabo Substation for a period of 530 days. The mineral content of the grasses under this experiment was comparable, but calcium and magnesium were definitely higher in Guinea grass. The lignin content of Signal grass was lower than that of Guinea grass; this difference, although small in favor of Signal grass, may have more importance in terms of animal digestibility than the chemical analyses indicate. The results obtained in relation to yielding ability and drought-resistance of this form of Signal grass are very encouraging. As the palatability of this grass has been found to be comparable to that of Napier grass, which is the standard grass used for palatability tests at this Station, it may be expected to occupy in due time a very important place as a forage crop throughout the Island of Puerto Rico, especially in the drought areas.

Sign in / Sign up

Export Citation Format

Share Document