Isolation and Fractionation of the Tobacco Stalk Lignin for Customized Value-Added Utilization

The value-added utilization of tobacco stalk lignin is the key to the development of tobacco stalk resources. However, the serious heterogeneity is the bottleneck for making full use of tobacco stalk lignin. Based on this, lignin was separated from tobacco stalk through hydrothermal assisted dilute alkali pretreatment. Subsequently, the tobacco stalk alkaline lignin was fractionated into five uniform lignin components by sequential solvent fractionation. Advanced spectral technologies (FT-IR, NMR, and GPC) were used to reveal the effects of hydrothermal assisted dilute alkali pretreatment and solvent fractionation on the structural features of tobacco stalk lignin. The lignin fractions extracted with n-butanol and ethanol had low molecular weight and high phenolic hydroxyl content, thus exhibiting superior chemical reactivity and antioxidant capacity. By contrast, the lignin fraction extracted with dioxane had high molecular weight and low reactivity, nevertheless, the high residual carbon rate made it suitable as a precursor for preparing carbon materials. In general, hydrothermal assisted dilute alkali pretreatment was proved to be an efficient method to separate lignin from tobacco stalk, and the application of sequential solvent fractionation to prepare lignin fractions with homogeneous structural features has specific application prospect.

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Isolating High Antimicrobial Ability Lignin From Bamboo Kraft Lignin by Organosolv Fractionation

Frontiers in Bioengineering and Biotechnology ◽

10.3389/fbioe.2021.683796 ◽

2021 ◽

Vol 9 ◽

Author(s):

Jinyan Yun ◽

Liao Wei ◽

Wei Li ◽

Duqiang Gong ◽

Hongyu Qin ◽

...

Keyword(s):

Escherichia Coli ◽

Molecular Weight ◽

Biological Activities ◽

Gel Permeation Chromatography ◽

Antimicrobial Activities ◽

Phenolic Hydroxyl ◽

Hydroxyl Content ◽

Lignin Fraction

Lignin from different biomasses possess biological antioxidation and antimicrobial activities, which depend on the number of functional groups and the molecular weight of lignin. In this work, organosolv fractionation was carried out to prepare the lignin fraction with a suitable structure to tailor excellent biological activities. Gel permeation chromatography (GPC) analysis showed that decreased molecular weight lignin fractions were obtained by sequentially organosolv fractionation with anhydrous acetone, 50% acetone and 37.5% hexanes. Nuclear magnetic resonance (NMR) results indicated that the lignin fractions with lower molecular weight had fewer substructures and a higher phenolic hydroxyl content, which was positively correlated with their antioxidation ability. Both of the original lignin and fractionated lignins possessed the ability to inhibit the growth of Gram-negative bacteria (Escherichia coli and Salmonella) and Gram-positive bacteria (Streptococcus and Staphylococcus aureus) by destroying the cell wall of bacteria in vitro, in which the lignin fraction with the lowest molecular weight and highest phenolic hydroxyl content (L3) showed the best performance. Besides, the L3 lignin showed the ability to ameliorate Escherichia coli-induced diarrhea damages of mice to improve the formation of intestinal contents in vivo. These results imply that a lignin fraction with a tailored structure from bamboo lignin can be used as a novel antimicrobial agent in the biomedical field.

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Chitosan hydrogel/silk fibroin/Mg(OH)2 nanobiocomposite as a novel scaffold with antimicrobial activity and improved mechanical properties

Scientific Reports ◽

10.1038/s41598-020-80133-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Reza Eivazzadeh-Keihan ◽

Fateme Radinekiyan ◽

Hooman Aghamirza Moghim Aliabadi ◽

Sima Sukhtezari ◽

Behnam Tahmasebi ◽

...

Keyword(s):

Antibacterial Activity ◽

Cell Viability ◽

Silk Fibroin ◽

Analytical Techniques ◽

Structural Features ◽

Mechanical Tests ◽

Chitosan Hydrogel ◽

Biological Capacity ◽

Ft Ir ◽

Novel Scaffold

AbstractHerein, a novel nanobiocomposite scaffold based on modifying synthesized cross-linked terephthaloyl thiourea-chitosan hydrogel (CTT-CS hydrogel) substrate using the extracted silk fibroin (SF) biopolymer and prepared Mg(OH)2 nanoparticles was designed and synthesized. The biological capacity of this nanobiocomposite scaffold was evaluated by cell viability method, red blood cells hemolytic and anti-biofilm assays. According to the obtained results from 3 and 7 days, the cell viability of CTT-CS/SF/Mg(OH)2 nanobiocomposite scaffold was accompanied by a considerable increment from 62.5 to 89.6% respectively. Furthermore, its low hemolytic effect (4.5%), and as well, the high anti-biofilm activity and prevention of the P. aeruginosa biofilm formation confirmed its promising hemocompatibility and antibacterial activity. Apart from the cell viability, blood biocompatibility, and antibacterial activity of CTT-CS/SF/Mg(OH)2 nanobiocomposite scaffold, its structural features were characterized using spectral and analytical techniques (FT-IR, EDX, FE-SEM and TG). As well as, given the mechanical tests, it was indicated that the addition of SF and Mg(OH)2 nanoparticles to the CTT-CS hydrogel could improve its compressive strength from 65.42 to 649.56 kPa.

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Extraction of sugarcane bagasse arabinoxylan, integrated with enzymatic production of xylo-oligosaccharides and separation of cellulose

Biotechnology for Biofuels ◽

10.1186/s13068-021-01993-z ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Leila Khaleghipour ◽

Javier A. Linares-Pastén ◽

Hamid Rashedi ◽

Seyed Omid Ranaei Siadat ◽

Andrius Jasilionis ◽

...

Keyword(s):

Sugarcane Bagasse ◽

Sugar Content ◽

Value Added ◽

Apparent Molecular Weight ◽

Bacillus Halodurans ◽

Glycoside Hydrolase Family ◽

High Concentration ◽

Enzymatic Production ◽

Successful Separation ◽

Ft Ir

AbstractSugarcane processing roughly generates 54 million tonnes sugarcane bagasse (SCB)/year, making SCB an important material for upgrading to value-added molecules. In this study, an integrated scheme was developed for separating xylan, lignin and cellulose, followed by production of xylo-oligosaccharides (XOS) from SCB. Xylan extraction conditions were screened in: (1) single extractions in NaOH (0.25, 0.5, or 1 M), 121 °C (1 bar), 30 and 60 min; (2) 3 × repeated extraction cycles in NaOH (1 or 2 M), 121 °C (1 bar), 30 and 60 min or (3) pressurized liquid extractions (PLE), 100 bar, at low alkalinity (0–0.1 M NaOH) in the time and temperature range 10–30 min and 50–150 °C. Higher concentration of alkali (2 M NaOH) increased the xylan yield and resulted in higher apparent molecular weight of the xylan polymer (212 kDa using 1 and 2 M NaOH, vs 47 kDa using 0.5 M NaOH), but decreased the substituent sugar content. Repeated extraction at 2 M NaOH, 121 °C, 60 min solubilized both xylan (85.6% of the SCB xylan), and lignin (84.1% of the lignin), and left cellulose of high purity (95.8%) in the residuals. Solubilized xylan was separated from lignin by precipitation, and a polymer with β-1,4-linked xylose backbone substituted by arabinose and glucuronic acids was confirmed by FT-IR and monosaccharide analysis. XOS yield in subsequent hydrolysis by endo-xylanases (from glycoside hydrolase family 10 or 11) was dependent on extraction conditions, and was highest using xylan extracted by 0.5 M NaOH, (42.3%, using Xyn10A from Bacillus halodurans), with xylobiose and xylotriose as main products. The present study shows successful separation of SCB xylan, lignin, and cellulose. High concentration of alkali, resulted in xylan with lower degree of substitution (especially reduced arabinosylation), while high pressure (using PLE), released more lignin than xylan. Enzymatic hydrolysis was more efficient using xylan extracted at lower alkaline strength and less efficient using xylan obtained by PLE and 2 M NaOH, which may be a consequence of polymer aggregation, via remaining lignin interactions.

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Hygroscopic behavior and chemical reactivity of aerosols generated from mixture solutions of low molecular weight dicarboxylic acids and NaCl

Physical Chemistry Chemical Physics ◽

10.1039/d1cp00590a ◽

2021 ◽

Author(s):

Xue Li ◽

Li Wu ◽

Ji-Soo Lee ◽

Chul-Un Ro

Keyword(s):

Molecular Weight ◽

Chemical Reactivity ◽

Dicarboxylic Acids ◽

Sea Spray ◽

Low Molecular Weight ◽

Hygroscopic Behavior

Ambient sea spray aerosols (SSAs) have been reported to undergo reactions with low molecular weight dicarboxylic acids (LMW DCAs). In the present study, the hygroscopic behavior of aerosols generated from...

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Investigating Lignin-Derived Monomers and Oligomers in Low-Molecular-Weight Fractions Separated from Depolymerized Black Liquor Retentate by Membrane Filtration

Molecules ◽

10.3390/molecules26102887 ◽

2021 ◽

Vol 26 (10) ◽

pp. 2887

Author(s):

Kena Li ◽

Jens Prothmann ◽

Margareta Sandahl ◽

Sara Blomberg ◽

Charlotta Turner ◽

...

Keyword(s):

Molecular Weight ◽

High Performance ◽

Membrane Filtration ◽

Black Liquor ◽

Complex Mixture ◽

Value Added ◽

Kraft Pulping ◽

Classification Model ◽

Low Molecular Weight ◽

Chemical Complexity

Base-catalyzed depolymerization of black liquor retentate (BLR) from the kraft pulping process, followed by ultrafiltration, has been suggested as a means of obtaining low-molecular-weight (LMW) compounds. The chemical complexity of BLR, which consists of a mixture of softwood and hardwood lignin that has undergone several kinds of treatment, leads to a complex mixture of LMW compounds, making the separation of components for the formation of value-added chemicals more difficult. Identifying the phenolic compounds in the LMW fractions obtained under different depolymerization conditions is essential for the upgrading process. In this study, a state-of-the-art nontargeted analysis method using ultra-high-performance supercritical fluid chromatography coupled to high-resolution multiple-stage tandem mass spectrometry (UHPSFC/HRMSn) combined with a Kendrick mass defect-based classification model was applied to analyze the monomers and oligomers in the LMW fractions separated from BLR samples depolymerized at 170–210 °C. The most common phenolic compound types were dimers, followed by monomers. A second round of depolymerization yielded low amounts of monomers and dimers, while a high number of trimers were formed, thought to be the result of repolymerization.

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Graft Copolymerization of Acrylamide onto Activated Starch Using Inverse Emulsion Polymerization

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.308-310.600 ◽

2011 ◽

Vol 308-310 ◽

pp. 600-605

Author(s):

Dian Mo Zheng ◽

Sheng Gan Zhu ◽

Li Ping Wu

Keyword(s):

Ball Milling ◽

Graft Copolymerization ◽

Chemical Reactivity ◽

Weight Ratio ◽

Monomer Conversion ◽

Ammonium Persulfate ◽

Grafting Efficiency ◽

Inverse Emulsion ◽

Initiation System ◽

Ft Ir

Activated starch was prepared by ball milling before used. Graft copolymerization of acrylamide onto activated starch was carried out in inverse emulsion using a redox initiation system of ammonium persulfate and sodium bisulfite. The effects of ball-milling time, reaction temperature, initiator concentration and weight ratio of acrylamide to starch on the conversion of monomer, grafting percentage and grafting efficiency were studied. The structure and properties of the graft copolymer and activated starch were characterized by FT-IR, XRD and SEM. The results showed that ball milling could progressively destroy the crystalline structure of starch and improve the chemical reactivity. The monomer conversion, grafting percentage and grafting efficiency of grate copolymerization were 96.6%、62.4%、85.49%, respectively.

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Graft modification in bamboo cellulose nanofibrils: An effective option to improve compatibility and tunable surface energy

10.21203/rs.3.rs-179487/v1 ◽

2021 ◽

Author(s):

Carlos Alejandro Rodríguez-Ramírez ◽

Alain Dufresne ◽

Norma Beatriz D'Accorso ◽

Nancy Garcia

Keyword(s):

Molecular Weight ◽

Thermal Properties ◽

Cellulose Nanofibrils ◽

Value Added ◽

Xrd Analysis ◽

Low Molecular Weight ◽

Mechanical And Thermal Properties ◽

Graft Modification ◽

Effective Option ◽

20 Nm

Abstract In this work, from an endemic and non-significant value-added bamboo argentine, nanofibrils (CNFs) of 20 nm in width were obtained. These nanofibrils were chemical modified in surface with three simple steps using a noncommercial low molecular weight polylactic acid. The success of modification was confirmed by FTIR, TGA, DSC and XRD analysis. The modified nanofibrils were taken up for changing surface properties in films based on commercial PLA. The results show that dispersive (γ D/S) component of films increase of 34.7 mN/m to 36.1 mN/m after the addition of modified nanofibrils from 2 to 5% in formulation of the films, comparing with a physical blend. Interesting others result in physical, mechanical, and thermal properties of the nanocomposites, were reported.

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Characterisation of Sequential Solvent Fractionation and Base-catalysed Depolymerisation of Treated Alkali Lignin

BioResources ◽

10.15376/biores.10.3.4137-4151 ◽

2015 ◽

Vol 10 (3) ◽

pp. 4137-4151 ◽

Cited By ~ 5

Author(s):

Aikfei Ang ◽

Zaidon Ashaari ◽

Edi Suhaimi Bakar ◽

Nor Azowa Ibrahim

Keyword(s):

Molecular Weight ◽

Chemical Structure ◽

Average Molecular Weight ◽

Gel Permeation Chromatography ◽

Solubility Parameters ◽

Low Molecular Weight ◽

Sequential Fractionation ◽

Weight Average Molecular Weight ◽

Solvent Fractionation ◽

Alkali Lignin

An alkali lignin (OL) with a weight-average molecular weight (Mw) of 11646 g/mol was used to prepare low-molecular weight lignin for resin synthesis. The low-molecular weight lignin feedstock was obtained via base-catalysed depolymerisation (BCD) treatments at different combined severity factors. Sequential fractionation of the OL and BCD-treated lignins using organic solvents with different Hildebrand solubility parameters were used to alter the homogeneity of the OL. The yield and properties of OL itself and OL and BCD-treated OL dissolved in propan-1-ol (F1), ethanol (F2), and methanol (F3) were determined. Regardless of the treatment applied, a small amount of OL was dissolved in F1 and F2. The BCD treatment did not increase the yield of F1 but did increase the yields of F2 and F3. Gel permeation chromatography (GPC) showed that the repolymerization reaction occurred in F3 for all BCD-treated OL, so these lignins were not suitable for use as feedstocks for resin production. The GPC, 13Carbon-nuclear magnetic resonance, and Fourier transform infrared spectroscopy analyses confirmed that the F3 in OL exhibited the optimum yield, molecular weight distribution, and chemical structure suitable for use as feedstocks for resin synthesis.

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ATRP Synthesis and Characterization of μ,αω-allyl-terminated Macromonomers as Precursors for End-linked Gels and Hydrogels

MRS Proceedings ◽

10.1557/proc-774-o1.8 ◽

2003 ◽

Vol 774 ◽

Author(s):

Lucy Vojtova ◽

Nicholas J. Turro ◽

Jeffrey T. Koberstein

Keyword(s):

Molecular Weight ◽

Monomer Concentration ◽

Monomer Conversion ◽

Catalyst System ◽

Linear Increase ◽

Butyl Methacrylate ◽

First Order Kinetics ◽

Significant Difference ◽

Ft Ir

AbstractSynthesis of α,ω-allyl-terminated telechelic macromonomers based on poly(tert-butyl methacrylate) (poly(t-BMA)) and poly(methacrylic acid) (poly(MAA)) was studied with the aim of preparing end-linked gels and hydrogels. Low molecular weight α-allyl-terminated poly(t-BMA) macromonomers with narrow polydispersities (Mw/Mn = 1.16) were synthesized via controlled atom transfer radical polymerization (ATRP) using a Cu(I)Br/N,N,N',N',N',N'-hexamethyltriethylenetetraamine catalyst system in conjunction with an allyl-2-bromoisobutyrate as the functional initiator. The polymerizations exhibited a linear increase of molecular weight in direct proportion to the monomer conversion and first-order kinetics with respect to monomer concentration. No significant difference was found between using polar or non-polar solvents (tetrahydrofuran or benzene, respectively). Optimization of reaction conditions to obtain the highest degree of active terminal bromine is discussed. Quenching the ATRP reaction with allyltributyltin yielded α,ω-allyl-terminated poly(t-BMA) macromonomers by replacing the terminal bromine with ω-allyl functional group. Poly(MAA) macromonomers were prepared by deprotection of the tert-butyl group from α,ω-allyl-terminated poly(t-BMA) macromonomers using concentrated trifluoroacetic acid at room temperature. Successful synthetic steps were confirmed by 1H NMR, FT-IR and MALDI-TOF MS analyses. The α,ω-allyl-terminated macromonomers were proven to be candidates for further polymerization by forming end-linked, non-soluble gels.

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Chitosan and Carboxymethyl Chitosan from Fish Scales of Labeo rohita

Dhaka University Journal of Science ◽

10.3329/dujs.v61i1.15116 ◽

2013 ◽

Vol 61 (1) ◽

pp. 145-148 ◽

Cited By ~ 6

Author(s):

Tanvir Muslim ◽

Mohammad Habibur Rahman ◽

HOsne Ara Begum ◽

Md. Azizur Rahman

Keyword(s):

Molecular Weight ◽

Spectral Analysis ◽

Labeo Rohita ◽

Carboxymethyl Chitosan ◽

Degree Of Substitution ◽

Monochloroacetic Acid ◽

Fish Scales ◽

Ft Ir

Chitin was extracted from the fish scales of Labeo rohita and chitosan was successfully prepared from it by deacetylation reaction. The prepared chtiosan was characterized by FT-IR spectral analysis and degree of decetylation was determined by pH-metric titration. The molecular weight of chitosan was estimated by viscometric method. Chitosan was converted into its carboxymethyl derivative using alkali and monochloroacetic acid. The prepared carboxymethyl chitosan was characterized by FT-IR spectral analysis and degree of substitution was estimated. Dhaka Univ. J. Sci. 61(1): 145-148, 2013 (January) DOI: http://dx.doi.org/10.3329/dujs.v61i1.15116

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