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Wang C, Holm PE, Andersen ML, Thygesen LG, Nielsen UG, Hansen HCB. Phosphorus doped cyanobacterial biochar catalyzes efficient persulfate oxidation of the antibiotic norfloxacin. Bioresour Technol 2023; 388:129785. [PMID: 37722544 DOI: 10.1016/j.biortech.2023.129785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 09/05/2023] [Accepted: 09/12/2023] [Indexed: 09/20/2023]
Abstract
In this study, cyanobacterial biochars (CBs) enriched/doped with non-metallic elements were prepared by pyrolysis of biomass amended with different N, S, and P containing compounds. Their catalytic reactivity was tested for persulfate oxidation of the antibiotic norfloxacin (NOR). N and S doping failed to improve CB catalytic reactivity, while P doping increased reactivity 5 times compared with un-doped biochar. Biochars produced with organic phosphorus dopants showed the highest reactivity. Post-acid-washing improved catalytic reactivity. In particular, 950 ℃ acid-washed triphenyl-phosphate doped CB showed the largest degradation rate and reached 79% NOR mineralization in 2 h. Main attributes for P-doped CBs high reactivity were large specific surface areas (up to 655 m2/g), high adsorption, high C-P-O content, graphitic P and non-radical degradation pathway (electron transfer). This study demonstrates a new way to reuse waste biomass by producing efficient P-doped metal-free biochars and presents a basic framework for designing carbon-based catalysts for organic pollutant degradation.
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Affiliation(s)
- Chen Wang
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark.
| | - Peter E Holm
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark
| | - Mogens Larsen Andersen
- Department of Food Science, University of Copenhagen, Rolighedsvej 26, DK-1958 Frederiksberg C, Denmark
| | - Lisbeth Garbrecht Thygesen
- Department of Geosciences and Natural Resource Management, University of Copenhagen, Rolighedsvej 23, DK-1958 Frederiksberg C, Denmark
| | - Ulla Gro Nielsen
- Department of Physics, Chemistry, and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark
| | - Hans Christian Bruun Hansen
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark
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2
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Ouyang Q, Hansen HCB, Thygesen LG, Tobler DJ. Nitrogen amended graphene catalyses fast reduction of vinyl chloride by nano zerovalent iron. Water Res 2023; 244:120535. [PMID: 37660466 DOI: 10.1016/j.watres.2023.120535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 07/05/2023] [Accepted: 08/26/2023] [Indexed: 09/05/2023]
Abstract
Vinyl chloride (VC) is a dominant carcinogenic residual in many aged chlorinated solvent plumes, and it remains a huge challenge to clean it up. Zerovalent iron (ZVI) is an effective reductant for many chlorinated compounds but shows low VC removal efficiency at field scale. Amendment of ZVI with a carbonaceous material may be used to both preconcentrate VC and facilitate redox reactions. In this study, nitrogen-doped graphene (NG) produced by a simple co-pyrolysis method using urea as nitrogen (N) source, was tested as a catalyst for VC reduction by nanoscale ZVI (nZVI). The extent of VC reduction to ethylene in the presence of 2 g/L of nZVI was less than 1% after 3 days, and barely improved with the addition of 4 g/L of graphene. In contrast, with amendment of nZVI with NG produced at pyrolysis temperature (PT) of 950 °C, the VC reduction extent increased more than 10-fold to 69%. The reactivity increased with NG PT increasing from 400 °C to an optimum at 950 °C, and it increased linearly with NG loadings. Interestingly, N dosage had little effect on reactivity if NG was produced at PT of 950 °C, while a positive correlation was observed for NG produced at PT of 600 °C. XPS and Raman analyses revealed that for NG produced at lower PT (<800 °C) mainly the content of pyridine-N-oxide (PNO) groups correlates with reactivity, while for NG produced at higher PT up to 950 °C, reactivity correlates mainly with N induced structural defects in graphene. The results of quenching and hydrogen yield experiments indicated that NG promote reduction of VC by storage of atomic hydrogen, thus increasing its availability for VC reduction, while likely also enabling electron transfer from nZVI to VC. Overall, these findings demonstrate effective chemical reduction of VC by a nZVI-NG composite, and they give insights into the effects of N doping on redox reactivity and hydrogen storage potential of carbonaceous materials.
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Affiliation(s)
- Qiong Ouyang
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, Frederiksberg C DK-1871, Denmark.
| | - Hans Christian Bruun Hansen
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, Frederiksberg C DK-1871, Denmark
| | - Lisbeth Garbrecht Thygesen
- Department of Geosciences and Natural Resource Management, University of Copenhagen, Rolighedsvej 23, Frederiksberg C DK-1958, Denmark
| | - Dominique J Tobler
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, Frederiksberg C DK-1871, Denmark
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3
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Ponzecchi A, Thybring EE, Digaitis R, Fredriksson M, Solsona SP, Thygesen LG. Raman micro-spectroscopy of two types of acetylated Norway spruce wood at controlled relative humidity. Front Plant Sci 2022; 13:986578. [PMID: 36147227 PMCID: PMC9486069 DOI: 10.3389/fpls.2022.986578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 08/15/2022] [Indexed: 06/16/2023]
Abstract
Water is a key element for wood performance, as water molecules interact with the wood structure and affect important material characteristics such as mechanical properties and durability. Understanding wood-water interactions is consequently essential for all applications of wood, including the design of wood materials with improved durability by chemical modification. In this work, we used Raman micro-spectroscopy in combination with a specially designed moisture chamber to map molecular groups in wood cell walls under controlled moisture conditions in the hygroscopic range. We analyzed both untreated and chemically modified (acetylated to achieve two different spatial distributions of acetyl groups within the cell wall) Norway spruce wood. By moisture conditioning the specimens successively to 5, 50, and 95% relative humidity using deuterium oxide (D2O), we localized the moisture in the cell walls as well as distinguished between hydroxyl groups accessible and inaccessible to water. The combination of Raman micro-spectroscopy with a moisturizing system with deuterium oxide allowed unprecedented mapping of wood-water interactions. The results confirm lower moisture uptake in acetylated samples, and furthermore showed that the location of moisture within the cell wall of acetylated wood is linked to the regions where acetylation is less pronounced. The study demonstrates the local effect that targeted acetylation has on moisture uptake in wood cell walls, and introduces a novel experimental set-up for simultaneously exploring sub-micron level wood chemistry and moisture in wood under hygroscopic conditions.
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Affiliation(s)
- Andrea Ponzecchi
- Bioresource Chemistry and Technology, Department of Geoscience and Natural Resource Management, University of Copenhagen, Frederiksberg, Denmark
| | - Emil E. Thybring
- Bioresource Chemistry and Technology, Department of Geoscience and Natural Resource Management, University of Copenhagen, Frederiksberg, Denmark
| | - Ramūnas Digaitis
- Division of Building Materials, Lund University, Lund, Sweden
- Department of Wood Technology, Norwegian Institute of Bioeconomy Research, Ås, Norway
- Department of Wood and Biomaterials, Danish Technological Institute, Taastrup, Denmark
| | | | - Sara Piqueras Solsona
- Bioresource Chemistry and Technology, Department of Geoscience and Natural Resource Management, University of Copenhagen, Frederiksberg, Denmark
| | - Lisbeth Garbrecht Thygesen
- Bioresource Chemistry and Technology, Department of Geoscience and Natural Resource Management, University of Copenhagen, Frederiksberg, Denmark
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4
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Füchtner S, Piqueras S, Thygesen LG. Defensive strategies of Norway spruce and Kurile larch heartwood elucidated on the micron-level. Sci Rep 2021; 11:22235. [PMID: 34782641 PMCID: PMC8593066 DOI: 10.1038/s41598-021-01590-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 10/28/2021] [Indexed: 11/08/2022] Open
Abstract
To decarbonize the building sector, the use of durable wood materials must be increased. Inspiration for environmentally benign wood protection systems is sought in durable tree species depositing phenolic extractives in their heartwood. Based on the hypothesis that the micro-distribution of extractives influences durability, we compared the natural impregnation patterns of non-durable, but readily available Norway spruce to more durable Kurile larch by mapping the distribution of heartwood extractives with Confocal Raman Imaging and multivariate data decomposition. Phenolics of both species were associated with hydrophobic oleoresin, likely facilitating diffusion through the tissue. They accumulated preferentially in lignin-rich sub-compartments of the cell wall. Yet, the distribution of extractives was found not to be the same. The middle lamellae contained flavonoids in larch and aromatic waxes in spruce, which was also found in rays and epithelial cells. Spruce-lignans were tentatively identified in all cell types, while larch-flavonoids were not present in resin channels, hinting at a different origin of synthesis. Larch-oleoresin without flavonoids was only found in lumina, indicating that the presence of phenolics in the mixture influences the final destination. Together our findings suggest, that spruce heartwood-defense focuses on water regulation, while the more efficient larch strategy is based on antioxidants.
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Affiliation(s)
- Sophie Füchtner
- Institute for Geoscience and Natural Resource Management, University of Copenhagen, Rolighedsvej 23, 1955, Frederiksberg, Denmark.
| | - Sara Piqueras
- Institute for Geoscience and Natural Resource Management, University of Copenhagen, Rolighedsvej 23, 1955, Frederiksberg, Denmark
- MS-OMICS, Bygstubben 9, 2950, Vedbæk, Denmark
| | - Lisbeth Garbrecht Thygesen
- Institute for Geoscience and Natural Resource Management, University of Copenhagen, Rolighedsvej 23, 1955, Frederiksberg, Denmark
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5
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Deralia PK, Jensen A, Felby C, Thygesen LG. Chemistry of lignin and hemicellulose structures interacts with hydrothermal pretreatment severity and affects cellulose conversion. Biotechnol Prog 2021; 37:e3189. [PMID: 34176230 DOI: 10.1002/btpr.3189] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 06/06/2021] [Accepted: 06/23/2021] [Indexed: 11/09/2022]
Abstract
Understanding of how the plant cell walls of different plant species respond to pretreatment can help improve saccharification in bioconversion processes. Here, we studied the chemical and structural modifications in lignin and hemicellulose in hydrothermally pretreated poplar and wheat straw using wet chemistry and 2D heteronuclear single quantum coherence nuclear magnetic resonance (NMR) and their effects on cellulose conversion. Increased pretreatment severity reduced the levels of β─O─4 linkages with concomitant relatively increased levels of β─5 and β─β structures in the NMR spectra. β─5 structures appeared at medium and high severities for wheat straw while only β─β structures were observed at all pretreatment severities for poplar. These structural differences accounted for the differences in cellulose conversion for these biomasses at different severities. Changes in the hemicellulose component include a complete removal of arabinosyl and 4-O-methyl glucuronosyl substituents at low and medium pretreatment severities while acetyl groups were found to be relatively resistant toward hydrothermal pretreatment. This illustrates the importance of these groups, rather than xylan content, in the detrimental role of xylan in cellulose saccharification and helps explain the higher poplar recalcitrance compared to wheat straw. The results point toward the need for both enzyme preparation development and pretreatment technologies to target specific plant species.
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Affiliation(s)
- Parveen Kumar Deralia
- Department of Geosciences and Natural Resource Management, University of Copenhagen, Frederiksberg, Denmark
| | - Anders Jensen
- Department of Geosciences and Natural Resource Management, University of Copenhagen, Frederiksberg, Denmark
| | - Claus Felby
- Department of Geosciences and Natural Resource Management, University of Copenhagen, Frederiksberg, Denmark
| | - Lisbeth Garbrecht Thygesen
- Department of Geosciences and Natural Resource Management, University of Copenhagen, Frederiksberg, Denmark
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6
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Prendin AL, Carrer M, Bjerregaard Pedersen N, Normand S, Hollesen J, Treier UA, Pividori M, Garbrecht Thygesen L. Chemical signature of Eurois occulta L. outbreaks in the xylem cell wall of Salix glauca L. in Greenland. Sci Total Environ 2021; 764:144607. [PMID: 33387770 DOI: 10.1016/j.scitotenv.2020.144607] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 11/29/2020] [Accepted: 12/17/2020] [Indexed: 06/12/2023]
Abstract
Insect defoliations are a major natural disturbance in high-latitude ecosystems and are expected to increase in frequency and severity due to current climatic change. Defoliations cause severe reductions in biomass and carbon investments that affect the functioning and productivity of tundra ecosystems. Here we combined dendro-anatomical analysis with chemical imaging to investigate the direct and lagged effects of insect outbreaks on carbon investment. We analysed the content of lignin vs. holocellulose, i.e. unspecified carbohydrates in xylem samples of Salix glauca L. collected at Iffiartarfik, Nuuk fjord, Greenland, featuring two outbreak events of the moth Eurois occulta L. Cross sections of the growth rings corresponding to both outbreaks ±3 years were analysed using confocal Raman imaging to identify possible chemical signatures related to insect defoliation on fibres, vessels, and ray parenchyma cells and to get insight into species-specific defence responses. Outbreak years with narrower rings and thinner fibre cell walls are accompanied by a change in the content of cell-wall polymers but not their underlying chemistry. Indeed, during the outbreaks the ratio between lignin and carbohydrates significantly increased in fibre but not vessel cell walls due to an increase in lignin content coupled with a reduced content of carbohydrates. Parenchyma cell walls and cell corners did not show any significant changes in the cell-wall biopolymer content. The selective adjustment of the cell-wall composition of fibres but not vessels under stressful conditions could be related to the plants priority to maintain an efficient hydraulic system rather than mechanical support. However, the higher lignin content of fibre cell walls formed during the outbreak events could increase mechanical stiffness to the thin walls by optimizing the available resources. Chemical analysis of xylem traits with Raman imaging is a promising approach to highlight hidden effects of defoliation otherwise overlooked with classical dendroecological methods.
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Affiliation(s)
- Angela Luisa Prendin
- University of Padova, TeSAF Department, Agripolis, Viale dell'Università, 16, 35020 Legnaro, PD, Italy; Aarhus University, Department of Biology, Ecoinformatics and Biodiversity, Ny Munkegade 116, building 1540, 8000 Aarhus C, Denmark.
| | - Marco Carrer
- University of Padova, TeSAF Department, Agripolis, Viale dell'Università, 16, 35020 Legnaro, PD, Italy.
| | | | - Signe Normand
- Aarhus University, Department of Biology, Ecoinformatics and Biodiversity, Ny Munkegade 116, building 1540, 8000 Aarhus C, Denmark; Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, Ny Munkegade 116, building 1540, 8000 Aarhus C, Denmark.
| | - Jørgen Hollesen
- The National Museum of Denmark, Environmental Archaeology and Material Science, IC Modewegsvej, Brede, 2800 Kgs. Lyngby, Denmark.
| | - Urs Albert Treier
- Aarhus University, Department of Biology, Ecoinformatics and Biodiversity, Ny Munkegade 116, building 1540, 8000 Aarhus C, Denmark; Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Department of Biology, Aarhus University, Ny Munkegade 116, building 1540, 8000 Aarhus C, Denmark.
| | - Mario Pividori
- University of Padova, TeSAF Department, Agripolis, Viale dell'Università, 16, 35020 Legnaro, PD, Italy.
| | - Lisbeth Garbrecht Thygesen
- University of Copenhagen, Faculty of Science, Department of Geosciences and Natural Resource Management, Rolighedsvej 23, 1958 Frederiksberg C, Denmark.
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7
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Digaitis R, Thybring EE, Thygesen LG. Investigating the role of mechanics in lignocellulosic biomass degradation during hydrolysis: Part II. Biotechnol Prog 2020; 37:e3083. [PMID: 32935452 PMCID: PMC7988658 DOI: 10.1002/btpr.3083] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 07/28/2020] [Accepted: 09/14/2020] [Indexed: 11/29/2022]
Abstract
Lignocellulose breakdown in biorefineries is facilitated by enzymes and physical forces. Enzymes degrade and solubilize accessible lignocellulosic polymers, primarily on fiber surfaces, and make fibers physically weaker. Meanwhile physical forces acting during mechanical agitation induce tearing and cause rupture and attrition of the fibers, leading to liquefaction, that is, a less viscous hydrolysate that can be further processed in industrial settings. This study aims at understanding how mechanical agitation during enzymatic saccharification can be used to promote fiber attrition. The effects of reaction conditions, such as substrate and enzyme concentration on fiber attrition rate and hydrolysis yield were investigated. To gain insight into the fiber attrition mechanism, enzymatic hydrolysis was compared to hydrolysis by use of hydrochloric acid. Results show that fiber attrition depends on several factors concerning reactor design and operation including drum diameter, rotational speed, mixing schedule, and concentrations of fibers and enzymes. Surprisingly, different fiber attrition patterns during enzymatic and acid hydrolysis were found for similar mixing schedules. Specifically, for tumbling mixing, slow continuous mixing appears to function better than faster, intermittent mixing even for the same total number of drum revolutions. The findings indicate that reactor design and operation as well as hydrolysis conditions are key to process optimization and that detailed insights are needed to obtain fast liquefaction without sacrificing saccharification yields.
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Affiliation(s)
- Ramūnas Digaitis
- Department of Geosciences and Natural Resource Management, Faculty of Science, University of Copenhagen, Frederiksberg C, Denmark.,Biofilms Research Center for Biointerfaces, Malmö University, Malmö, Sweden
| | - Emil Engelund Thybring
- Department of Geosciences and Natural Resource Management, Faculty of Science, University of Copenhagen, Frederiksberg C, Denmark
| | - Lisbeth Garbrecht Thygesen
- Department of Geosciences and Natural Resource Management, Faculty of Science, University of Copenhagen, Frederiksberg C, Denmark
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8
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Füchtner S, Brock-Nannestad T, Smeds A, Fredriksson M, Pilgård A, Thygesen LG. Hydrophobic and Hydrophilic Extractives in Norway Spruce and Kurile Larch and Their Role in Brown-Rot Degradation. Front Plant Sci 2020; 11:855. [PMID: 32695126 PMCID: PMC7339921 DOI: 10.3389/fpls.2020.00855] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 05/27/2020] [Indexed: 05/06/2023]
Abstract
Extractives found in the heartwood of a moderately durable conifer (Larix gmelinii var. japonica) were compared with those found in a non-durable one (Picea abies). We identified and quantified heartwood extractives by extraction with solvents of different polarities and gas chromatography with mass spectral detection (GC-MS). Among the extracted compounds, there was a much higher amount of hydrophilic phenolics in larch (flavonoids) than in spruce (lignans). Both species had similar resin acid and fatty acid contents. The hydrophobic resin components are considered fungitoxic and the more hydrophilic components are known for their antioxidant activity. To ascertain the importance of the different classes of extractives, samples were partially extracted prior to subjection to the brown-rot fungus Rhodonia placenta for 2-8 weeks. Results indicated that the most important (but rather inefficient) defense in spruce came from the fungitoxic resin, while large amounts of flavonoids played a key role in larch defense. Possible moisture exclusion effects of larch extractives were quantified via the equilibrium moisture content of partially extracted samples, but were found to be too small to play any significant role in the defense against incipient brow-rot attack.
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Affiliation(s)
- Sophie Füchtner
- Department of Geoscience and Natural Resource Management, University of Copenhagen, Copenhagen, Denmark
| | | | - Annika Smeds
- Laboratory of Wood and Paper Chemistry, Johan Gadolin Process Chemistry Centre, Åbo Akademi University, Turku, Finland
| | - Maria Fredriksson
- Faculty of Engineering, Division of Building Materials, Lund University, Lund, Sweden
| | - Annica Pilgård
- Wood Research Munich, Technical University of Munich, Munich, Germany
- Research Institutes of Sweden (RISE), Gothenburg, Sweden
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9
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Piqueras S, Füchtner S, Rocha de Oliveira R, Gómez-Sánchez A, Jelavić S, Keplinger T, de Juan A, Thygesen LG. Understanding the Formation of Heartwood in Larch Using Synchrotron Infrared Imaging Combined With Multivariate Analysis and Atomic Force Microscope Infrared Spectroscopy. Front Plant Sci 2019; 10:1701. [PMID: 32117328 PMCID: PMC7008386 DOI: 10.3389/fpls.2019.01701] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 12/03/2019] [Indexed: 05/03/2023]
Abstract
Formation of extractive-rich heartwood is a process in live trees that make them and the wood obtained from them more resistant to fungal degradation. Despite the importance of this natural mechanism, little is known about the deposition pathways and cellular level distribution of extractives. Here we follow heartwood formation in Larix gmelinii var. Japonica by use of synchrotron infrared images analyzed by the unmixing method Multivariate Curve Resolution - Alternating Least Squares (MCR-ALS). A subset of the specimens was also analyzed using atomic force microscopy infrared spectroscopy. The main spectral changes observed in the transition zone when going from sapwood to heartwood was a decrease in the intensity of a peak at approximately 1660 cm-1 and an increase in a peak at approximately 1640 cm-1. There are several possible interpretations of this observation. One possibility that is supported by the MCR-ALS unmixing is that heartwood formation in larch is a type II or Juglans-type of heartwood formation, where phenolic precursors to extractives accumulate in the sapwood rays. They are then oxidized and/or condensed in the transition zone and spread to the neighboring cells in the heartwood.
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Affiliation(s)
- Sara Piqueras
- Biomass Science and Technology Group, Department of Geosciences and Natural Resource Management, University of Copenhagen, Frederiksberg, Denmark
- *Correspondence: Sara Piqueras,
| | - Sophie Füchtner
- Biomass Science and Technology Group, Department of Geosciences and Natural Resource Management, University of Copenhagen, Frederiksberg, Denmark
| | | | - Adrián Gómez-Sánchez
- Chemometrics Group, Department of Analytical Chemistry, University of Barcelona, Barcelona, Spain
| | - Stanislav Jelavić
- Nano-Science Center, Department of Chemistry, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
- Section for GeoGenetics, Faculty of Health and Medical Sciences, Globe Institute, University of Copenhagen, Copenhagen, Denmark
| | - Tobias Keplinger
- Wood Material Science Group, Department of Construction, Environment and Geomatics, Institute for Building Materials (IfB), ETH Zürich, Zürich, Switzerland
- WoodTec Group, Cellulose & Wood Materials, EMPA, Dübendorf, Switzerland
| | - Anna de Juan
- Chemometrics Group, Department of Analytical Chemistry, University of Barcelona, Barcelona, Spain
| | - Lisbeth Garbrecht Thygesen
- Biomass Science and Technology Group, Department of Geosciences and Natural Resource Management, University of Copenhagen, Frederiksberg, Denmark
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10
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Digaitis R, Thybring EE, Thygesen LG. Investigating the role of mechanics in lignocellulosic biomass degradation during hydrolysis. Biotechnol Prog 2018; 35:e2754. [PMID: 30468315 DOI: 10.1002/btpr.2754] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 10/13/2018] [Accepted: 11/20/2018] [Indexed: 11/12/2022]
Abstract
Enzymes and mechanics play major roles in lignocellulosic biomass deconstruction in biorefineries by catalyzing chemical cleavage or inducing physical breakdown of biomass, respectively. At industrially relevant substrate concentrations mechanical agitation is also a driving force for mass transfer as well as agglomeration of elongated biomass particles. Contrary to the physically induced particle attrition, which typically facilitates feedstock handling, particle agglomeration tends to hinder mass transfer and in the worst case induces processing difficulties like pipe blockage. Understanding the complex interplay between mechanical agitation and enzymatic degradation during hydrolysis is therefore critical and was the aim of this study. Particle size analyses revealed that neither mechanical agitation alone nor enzymatic treatment without mechanical agitation had any noteworthy effect on flax fiber attrition. Similarly, successive treatment, where mechanical agitation was either preceded or proceeded by enzymatic hydrolysis, did not induce any substantial segmentation of flax fibers. Simultaneous enzymatic and mechanical treatment on the other hand was found to promote fast fiber shortening. Higher hydrolysis yields, however, were obtained from nonagitated samples after prolonged enzymatic treatment, indicating that mechanical agitation in the long run reduces activity of the cellulolytic enzymes. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2754, 2019.
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Affiliation(s)
- Ramūnas Digaitis
- Dept. of Geosciences and Natural Resource Management, Faculty of Science, University of Copenhagen, Rolighedsvej 23, Frederiksberg C, Denmark
| | - Emil Engelund Thybring
- Dept. of Geosciences and Natural Resource Management, Faculty of Science, University of Copenhagen, Rolighedsvej 23, Frederiksberg C, Denmark
| | - Lisbeth Garbrecht Thygesen
- Dept. of Geosciences and Natural Resource Management, Faculty of Science, University of Copenhagen, Rolighedsvej 23, Frederiksberg C, Denmark
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11
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Weiss ND, Thygesen LG, Felby C, Roslander C, Gourlay K. Biomass-water interactions correlate to recalcitrance and are intensified by pretreatment: An investigation of water constraint and retention in pretreated spruce using low field NMR and water retention value techniques. Biotechnol Prog 2016; 33:146-153. [DOI: 10.1002/btpr.2398] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 09/28/2016] [Indexed: 11/06/2022]
Affiliation(s)
- Noah D. Weiss
- Dept. of Geosciences and Natural Resource Management; University of Copenhagen; Copenhagen Denmark
| | | | - Claus Felby
- Dept. of Geosciences and Natural Resource Management; University of Copenhagen; Copenhagen Denmark
| | | | - Keith Gourlay
- Dept. of Forest Products, Biotechnology and Bioenergy; University of British Columbia; Vancouver Canada
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12
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Kračun SK, Schückel J, Westereng B, Thygesen LG, Monrad RN, Eijsink VGH, Willats WGT. A new generation of versatile chromogenic substrates for high-throughput analysis of biomass-degrading enzymes. Biotechnol Biofuels 2015; 8:70. [PMID: 25969695 PMCID: PMC4428106 DOI: 10.1186/s13068-015-0250-y] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 03/30/2015] [Indexed: 05/02/2023]
Abstract
BACKGROUND Enzymes that degrade or modify polysaccharides are widespread in pro- and eukaryotes and have multiple biological roles and biotechnological applications. Recent advances in genome and secretome sequencing, together with associated bioinformatic tools, have enabled large numbers of carbohydrate-acting enzymes to be putatively identified. However, there is a paucity of methods for rapidly screening the biochemical activities of these enzymes, and this is a serious bottleneck in the development of enzyme-reliant bio-refining processes. RESULTS We have developed a new generation of multi-coloured chromogenic polysaccharide and protein substrates that can be used in cheap, convenient and high-throughput multiplexed assays. In addition, we have produced substrates of biomass materials in which the complexity of plant cell walls is partially maintained. CONCLUSIONS We show that these substrates can be used to screen the activities of glycosyl hydrolases, lytic polysaccharide monooxygenases and proteases and provide insight into substrate availability within biomass. We envisage that the assays we have developed will be used primarily for first-level screening of large numbers of putative carbohydrate-acting enzymes, and the assays have the potential to be incorporated into fully or semi-automated robotic enzyme screening systems.
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Affiliation(s)
- Stjepan Krešimir Kračun
- />Department of Plant and Environmental Sciences, Thorvaldsensvej 40, Frederiksberg, C 1871 Denmark
| | - Julia Schückel
- />Department of Plant and Environmental Sciences, Thorvaldsensvej 40, Frederiksberg, C 1871 Denmark
| | - Bjørge Westereng
- />Department of Plant and Environmental Sciences, Thorvaldsensvej 40, Frederiksberg, C 1871 Denmark
- />Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Chr. M. Falsens vei 1., Aas, 1432 Norway
- />University of Copenhagen, Faculty of Science, Rolighedsvej 23, Frederiksberg, C 1958 Denmark
| | | | | | - Vincent G H Eijsink
- />Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, Chr. M. Falsens vei 1., Aas, 1432 Norway
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Skovgaard PA, Thygesen LG, Jørgensen H, Cardona M, Tozzi E, McCarthy M, Siika-Aho M, Jeoh T. The role of endoglucanase and endoxylanase in liquefaction of hydrothermally pretreated wheat straw. Biotechnol Prog 2014; 30:923-31. [PMID: 24610675 DOI: 10.1002/btpr.1893] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Revised: 01/18/2014] [Indexed: 11/12/2022]
Abstract
The role of endocellulases and endoxylanase during liquefaction and saccharification of hydrothermally pretreated wheat straw was studied. The use of a flow-loop setup with in-line magnetic resonance imaging enabled frequent measurements of viscosity at 55°C during saccharification at 6% total solids content. Viscosity data were complemented with off-line measurements of fiber lengths and release of soluble sugars. A clear correlation between fiber attrition and a decrease in viscosity was found. Fiber lengths and viscosity dropped quickly within the first hour and then stagnated, while sugar yields increased substantially thereafter, illustrating that liquefaction and saccharification are separate mechanisms. Both endoglucanase and endoxylanase were shown to have a significant effect on viscosity during liquefaction while the addition of endoxylanase also increased sugar yield.
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Thygesen LG, Hidayat BJ, Johansen KS, Felby C. Role of supramolecular cellulose structures in enzymatic hydrolysis of plant cell walls. J Ind Microbiol Biotechnol 2010; 38:975-83. [PMID: 20852928 DOI: 10.1007/s10295-010-0870-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2010] [Accepted: 08/31/2010] [Indexed: 11/28/2022]
Abstract
The study of biomass deconstruction by enzymatic hydrolysis has hitherto not focussed on the importance of supramolecular structures of cellulose. In lignocellulose fibres, regions with a different organisation of the microfibrils are present. These regions are called dislocations or slip planes and they are known to be more susceptible to various forms of degradation such as acid hydrolysis. Traditionally the cellulose within these regions has been assumed to be amorphous, but in this study it is shown by use of polarized light microscopy that dislocations are birefringent. This indicates that they have a crystalline organisation. Dislocations may be entry points for endoglucanases. Using a fluorescent labelled endoglucanase combined with confocal fluorescence microscopy, it is shown that the enzyme selectively binds to dislocations during the initial phase of the hydrolysis. Using a commercial cellulase mixture on hydrothermally treated wheat straw, it was found that the fibres were cut into segments corresponding to the sections between the dislocations initially present, as has previously been observed for acid hydrolysis of softwood pulps. The results indicate that dislocations are important during the initial part of enzymatic hydrolysis of cellulose. The implications of this phenomenon have not yet been recognized or explored within cellulosic biofuels.
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Affiliation(s)
- Lisbeth Garbrecht Thygesen
- Forest and Landscape, Faculty of Life Sciences, University of Copenhagen, Rolighedsvej 23, 1958, Frederiksberg C, Denmark.
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15
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Thygesen LG, Jørgensen K, Møller BL, Engelsen SB. Raman spectroscopic analysis of cyanogenic glucosides in plants: development of a flow injection surface-enhanced Raman scatter (FI-SERS) method for determination of cyanide. Appl Spectrosc 2004; 58:212-217. [PMID: 15000716 DOI: 10.1366/000370204322842959] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Cyanogenic glucosides were studied using Raman spectroscopy. Spectra of the crystal forms of linamarin, linustatin, neolinustatin, amygdalin, sambunigrin, and dhurrin were obtained using a Raman spectrograph microscope equipped with a 532 nm laser. The position of the signal from the C identical with N triple bond of the cyanohydrin group was influenced by the nature of the side group and was above 2240 cm(-1) for the three cyanogenic glucosides that contain a neighboring aromatic ring, and below or partially below 2240 cm(-1) for the non-aromatic cyanoglucosides. Signals from the CN bond of linamarin/lotaustralin in leaves and roots from a medium cyanogenic cassava variety were obtained in situ using a Fourier transform near-infrared (FT-NIR) Raman interferometer with a 1064 nm laser, but the signal was very weak and difficult to obtain. A spectrum containing a signal from the CN bond of dhurrin in a freeze-dried sorghum leaf was also obtained using this instrument. Surface-enhanced Raman Spectroscopy (SERS) was demonstrated to be a more sensitive method that enabled determination of the cyanogenic potential of plant tissue. The SERS method was optimized by flow injection (FI) using a colloidal gold dispersion as effluent. Potential problems and pitfalls of the method are discussed.
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Affiliation(s)
- Lisbeth Garbrecht Thygesen
- Centre for Advanced Food Studies, Department of Dairy and Food Science, Food Technology, The Royal Veterinary and Agricultural University, 30 Rolighedsvej, DK-1958 Frederiksberg C, Denmark
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Barsberg S, Thygesen LG. Spectroscopic properties of oxidation species generated in the lignin of wood fibers by a laccase catalyzed treatment: electronic hole state migration and stabilization in the lignin matrix. Biochim Biophys Acta 1999; 1472:625-42. [PMID: 10564777 DOI: 10.1016/s0304-4165(99)00192-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A laccase catalyzed oxidative treatment of wood pulp fibers has been found to induce unusual modifications of these fibers that are qualitatively different from those encountered when more severely degraded fibers are subjected to similar enzymatically catalyzed oxidative treatments. These results suggest that the physical/conformational state of the lignin of wood fibers determines which oxidation pathways dominate in a given oxidative treatment, leading to different lignin modifications depending on both the chemical and the physical structure of the lignin polymer. Spectroscopic measurements (ESR, IR, UV-Vis and fluorescence) show that the laccase treatment results in the formation of two different species in the dried fibers: one is interpreted as chemically transformed (via oxygen) lignin products, and the other as initial oxidation radicals which have gained stabilization against transformation into the first mentioned products via a migration mechanism. It is argued that these initial radicals may likely be cation radical (or hole state) parts in lignin. The migration mechanism is identified with site-to-site transfer or 'hopping' via electron transfer and it is postulated that this mechanism 'carries' cation radical parts of the lignin, produced at the surface of the fiber, into parts of the lignin where chemical transformation pathways are suppressed due to the lignin conformational state. The possible existence of such a migration mechanism, the relative dominance of which should depend sensitively on the polymer conformational state, may have implications for the biogeneration and biodegradation of lignin as well as for oxidative treatments of non-natural conjugated polymers.
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Affiliation(s)
- S Barsberg
- Plant Fibre Laboratory, The Royal Veterinary and Agricultural University, Agrovej 10, DK-2630, Taastrup, Denmark.
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