Lignin Composition Research Articles

Overexpression of the patatin-related phospholipase A gene, PgpPLAIIIβ, in ginseng adventitious roots reduces lignin and ginsenoside content while increasing fatty acid content.

The patatin-related phospholipase AIII (pPLAIII) gene family plays a crucial role in regulating cell elongation, cell wall composition, and lipid metabolism in plants, making it a promising target for agricultural and commercial innovations. This study provides a comprehensive functional analysis of PgpPLAIIIβ in Panax ginseng, a medicinal plant of substantial economic importance. Overexpression of PgpPLAIIIβ led to significant morphological changes, including shorter, thicker roots, and an 8% reduction in lignin content, while cellulose levels remained unaffected. The reduced lignification was attributed to the downregulation of key lignin biosynthetic genes and decreased hydrogen peroxide accumulation. A yeast two-hybrid assay identified a CCCH-type zinc finger protein as a potential PgpPLAIIIβ interactor, pointing to a mechanism that may underlie the changes in root structure and lignin deposition. Metabolite analysis revealed a 7.6% increase in total free fatty acid content, with notable increases in palmitic and linoleic acids, alongside a 28% reduction in ginsenoside levels, linked to the downregulation of triterpenoid biosynthetic genes. These findings demonstrate that PgpPLAIIIβ is a key regulator of root architecture, lignin composition, and secondary metabolite balance in ginseng. The metabolic engineering of PgpPLAIIIβ could be a powerful strategy to improve root traits, optimize lignin deposition, and enhance metabolite profiles, ultimately boosting the commercial and medicinal value of ginseng.

Effects of Elevated CO2 on Maize Physiological and Biochemical Processes

Maize (Zea mays) is a critical global crop, serving as a source of food, livestock feed, and industrial raw materials. Climate changes, driven by rising atmospheric carbon dioxide (CO2) levels, have substantial effects on maize physiology, growth, and nutrient content. This review investigates the impact of elevated CO2 on maize, with a particular focus on photosynthesis enhancement as it improves water use efficiency (WUE), which can lead to increased biomass production. Despite this, elevated CO2 results in a decreased concentration of essential nutrients, including nitrogen, phosphorus, potassium, and folate. The reduction in folate, which is vital for both plant development and human nutrition, poses challenges, especially for population heavily reliant on maize. Additionally, biofortification through traditional breeding and genetic engineering is proposed as a strategy to enhance folate level in maize to mitigate nutritional deficiencies. Elevated CO2 stimulates lignin production, improving stress resistance and carbon sequestration capacity. However, the increase in guaiacyl-rich lignin may negatively affect biomass degradability and efficiency in biofuel production. The findings emphasize the importance of balancing maize’s stress resilience, nutrient profile, and lignin composition to address future climate challenges. This balance is essential for optimizing maize cultivation for food security, biofuel production, and environmental sustainability.

Value of horse manure for renewable energy production: anaerobic digestion, biogas generation, and contributions to sustainable development

There are various methods like composting, combustion, gasification, pyrolysis, and anaerobic digestion to convert animal wastes that harm the environment into various bio-products. Horse manure containing lower ash and higher rate of lignin compositions can be potentially reuse as a valuable feedstock in anaerobic digestion method to produce nutrient-rich digestate (bio-fertilizer) clean and cheap biofuels, and bio-energy to replace the cost effective fossil fuels which not only make climate change but harms our health by generating toxic emissions and contamination of soil and water. Therefore, converting bio wastes into useful green resources especially using anaerobic co-digestion is necessary to reduce their adverse environmental impact and can contributes towards the achievement of sustainable development goals (SDGs) 2, 3, 5, 6, 7, 9, 12, 13 and 15. As can be seen today, various animal manure types have begun to be used in different situations for their green benefits. This review aimed to provide an overview of the transformation of horse manure into compost, biogas in terms of its preferability as a renewable energy source or a value-added product that mitigate the environmental problems and contribute to the SDGs specially 7, 9, 12, and 13. The potential of animal manure to produce biomaterials, organic acids, biofuels and bioenergy is clear. Therefore, bioprocesses or biorefineries using this biomass as raw material may be promising in the near future in the context of bioeconomy, may help increase renewable energy production and may become capable of promoting innovation that boosts the value of livestock-derived organic fertilizers. There are still needs to extend the development of technologies for converting on-site bio waste resources to useful forms, exploring new and safe biological conversion pathways and bio waste processing methods.

Unraveling the dynamics of lignin chemistry on decomposition to understand its contribution to soil organic matter accumulation

Abstract Aims Plant inputs are the primary organic carbon source that transforms into soil organic matter (SOM) through microbial processing. One prevailing view is that lignin plays a major role in the accumulation of SOM. This study investigated lignin decomposition using wood from different genotypes of Populus tremula as the model substrate. The genotypes naturally varied in lignin content and composition, resulting in high and low lignin substrates. Methods The wood was inoculated with fresh soil and decomposition was interpreted through mass loss and CO2 produced during a 12-month lab incubation. Detailed information on the decomposition patterns of lignin was obtained by Two-dimensional Nuclear magnetic resonance (2D NMR) spectroscopy on four occasions during the incubations. Results The lignin content per se did not affect the overall decomposition and ~ 60% of the mass was lost in both substrates. In addition, no differences in oxidative enzyme activity could be observed, and the rate of lignin decomposition was similar to that of the carbohydrates. The 2D NMR analysis showed the oxidized syringyl present in the initial samples was the most resistant to degradation among lignin subunits as it followed the order p-hydroxybenzoates > syringyl > guaiacyl > oxidized syringyl. Furthermore, the degradability of β–O–4 linkages in the lignin varied depending on the subunit (syringyl or guaiacyl) it is attached to. Conclusions Our study demonstrates that lignin contains fractions that are easily degradable and can break down alongside carbohydrates. Thus, the initial differences in lignin content per se do not necessarily affect magnitude of SOM accumulation.

Salt marsh litter decomposition varies more by litter type than by extent of sea-level inundation

Salt marshes are among the most efficient blue carbon sinks worldwide. The fate of this carbon is uncertain due to limited knowledge about organic matter (OM) decomposition processes under sea-level rise. In an in-situ manipulative experiment, we compared salt marsh OM decomposition and quality across simulated sea-level scenarios (by modifying the inundation) and litter types (absorptive root, fine transportive root, leaves, and rhizomes of Halimione portulacoide) for 170 days. The litter decomposition varied only between the inundation treatments with the longest and shortest durations, while the decomposition differed significantly across litter types, with absorptive roots releasing up to 40% less carbon than other litters. Changes in lignin composition were minimal for absorptive roots and were unaffected by sea-level rise scenarios. Our study suggests that (i) current projections of sea-level rise are unlikely to decrease litter decomposition; (ii) separating litter types might lead to better assessments of salt marshes’ OM dynamics.

Characterisation of Miswak (Salvadora persica) Fibre-reinforced Polylactic Acid Composites Prepared by Twin Screw Extrusion

Processing of polymer composites employing fibres from sustainable sources as reinforcement has drastically grown in recent years. This research used Miswak fibres (MF) and polylactic acid (PLA) as the main materials for composite processing. Natural fibres typically include a hydroxyl group (-OH), which makes them hydrophilic. In contrast, the hydrophobic nature of polymer matrices causes them to naturally repel water. This problem was resolved by chemically altering the surface of natural fibres using a 2 wt% sodium hydroxide (NaOH) solution. In this paper, the effect of alkaline treatment has been proven by performing chemical analysis, tensile properties, thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) to analyse the influence of treated MF content on composite characteristics. The results revealed that biocomposites with modified miswak fibres exhibited better properties than untreated miswak fibres-reinforced polymer biocomposites. Treated MF/PLA composites showed an increase in tensile strength of 52.9% and tensile modulus of 8.16%. From the chemical composition test, lignin composition was reduced from 5.09% to 3.06% and hemicellulose from 28.12 to 10.62% after MF was treated. Meanwhile, thermal properties for both TGA and DSC revealed the elimination of hemicellulose and lignin characteristic peaks, improving the thermal stability of the treated MF/PLA composite. Thus, compared to a pristine sample, the resultant composites' higher mechanical strength and thermal stability demonstrated the significance of chemically treated natural fibres. The novelty of this research is the data on miswak fibre treatment, as no research has been found for this selected treated fibre.

Beyond low lignin: Identifying the primary barrier to plant biomass conversion by fermentative bacteria.

Renewable alternatives for nonelectrifiable fossil-derived chemicals are needed and plant matter, the most abundant biomass on Earth, provide an ideal feedstock. However, the heterogeneous polymeric composition of lignocellulose makes conversion difficult. Lignin presents a formidable barrier to fermentation of nonpretreated biomass. Extensive chemical and enzymatic treatments can liberate fermentable carbohydrates from plant biomass, but microbial routes offer many advantages, including concomitant conversion to industrial chemicals. Here, testing of lignin content of nonpretreated biomass using the cellulolytic thermophilic bacterium, Anaerocellum bescii, revealed that the primary microbial degradation barrier relates to methoxy substitutions in lignin. This contrasts with optimal lignin composition for chemical pretreatment that favors high S/G ratio and low H lignin. Genetically modified poplar trees with diverse lignin compositions confirm these findings. In addition, poplar trees with low methoxy content achieve industrially relevant levels of microbial solubilization without any pretreatments and with no impact on tree fitness in greenhouse.

Expression of laccase and ascorbate oxidase affects lignin composition in Arabidopsis thaliana stems.

Lignin is a phenolic polymer that is a major source of biomass. Oxidative enzymes, such as laccase and peroxidase, are required for lignin polymerisation. Laccase is a member of the multicopper oxidase family and has a high amino acid sequence similarity with ascorbate oxidase. However, the process of functional differentiation between the two enzymes remains poorly understood. In this study, the common ancestry sequence of laccase and ascorbate oxidase (AncMCO) was predicted via phylogenetic reconstruction, and its in vivo effect on lignin biosynthesis in Arabidopsis thaliana was assessed. The estimated AncMCO sequence conserved key residues that coordinate with copper ions, implying that the electron transfer system is likely to be conserved in AncMCO. However, multiple insertions/deletions corresponding to protein surface structures have been found between laccase, ascorbate oxidase, and AncMCO. The overexpression of canonical laccase (AtLAC4) and ascorbate oxidase (AtAAO1) in A. thaliana resulted in notable increases of syringyl/guaiacyl lignin unit ratio in stems, whereas, in contrast, the overexpression of AncMCO did not show any detectable change in lignin deposition. Transcriptomic analysis revealed that the AtAAO1-overexpressing line exhibited significant changes in the expression of a wide range of cell wall biosynthesis genes. These results highlight the importance of the molecular evolution of multicopper oxidase, which drives lignin biosynthesis during plant evolution.

Machine learning prediction of stalk lignin content using Fourier transform infrared spectroscopy in large scale maize germplasm

Lignin has been recognized as a major factor contributing to lignocellulosic recalcitrance in biofuel production and attracted attentions as a high-value product in the biorefinery field. As the traditional wet chemical methods for detecting lignin content are labor-intensive, time-consuming and environment-toxic, it is an urgent need to develop high-throughput and environment-friendly techniques for large-scale crop germplasms screening. In this study, we conducted a Fourier transform infrared (FTIR) assay on 150 maize germplasms with a diverse lignin composition to build predictive models for lignin content in maize stalk. Principal component analysis (PCA) was applied to the FTIR spectra for use as model inputs. Classification and advanced gradient boosting machine (GBM) algorithms demonstrated higher predictive accuracy (0.82–0.96) compared to traditional linear and regularization algorithms (0.03–0.04) in the training set. Notably, two optimal models, built using the extreme gradient boosting (XGBoost) and light gradient boosting machine (LightGBM) algorithms, achieved R2 values of over 0.91 in the training set and over 0.82 in the test set. Overall, the combination of FTIR and machine learning (ML) algorithms offers a high-throughput and efficient method for predicting lignin content. This approach holds significant potential for genetic breeding and the effective utilization of maize in industrial production.

Sustainable Lignin Extraction Using a Mild Acidic γ-Valerolactone Process for the Identification of White and Red Oaks.

Current wood identification struggles to differentiate white and red oak (Quercus alba and Quercus rubra) due to highly similar microstructures, as demonstrated by morphological microscope analysis. The present research explores lignin composition as a potential discriminating factor. Here, a rapid and sustainable method for extracting high-quality lignin from oak samples using acidic γ-valerolactone (GVL) under mild conditions is described. As-extracted lignin is thoroughly characterized using various analytical methods, and results reveal a distinct structural difference between the lignin from the two species. White oak lignin possesses a unique "Hibbert ketone" unit detectable by nuclear magnetic resonance spectroscopy (NMR), which is absent in red oak lignin. In addition, infrared spectroscopy differentiates the species based on specific carbonyl groups present in their lignin. These findings suggest that identifying the presence of the Hibbert ketone unit in lignin may offer a highly efficient and reliable method for differentiating white and red oak, opening new avenues for wood identification.

Computational study on the impact of linkage sequence on the structure and dynamics of lignin.

Lignin, one of the most abundant biopolymers on Earth, is of great research interest due to its industrial applications including biofuel production and materials science. The structural composition of lignin plays an important role in shaping its properties and functionalities. Notably, lignin exhibits substantial compositional diversity, which varies not only between different plant species but even within the same plant. Currently, it is unclear to what extent this compositional diversity plays on the overall structure and dynamics of lignin. To address this question, this paper reports on the development of two models of lignin containing all guaiacyl (G) subunits with varied linkage sequences and makes use of all-atom molecular dynamics simulations to examine the impact of linkage sequence alone on the lignin's structure and dynamics. This work demonstrates that the structure of the lignin polymer depends on its linkage sequence at temperatures above and below the glass transition temperature ( ), but the polymers exhibit similar structural properties as it is approaching the viscous flow state (480 K). At low temperatures, both of lignin models have a local dynamics confined in a cage, but the size of cages varies depending on structural differences. Interestingly, at temperatures higher than , the different linkage sequence leads to the subtle dynamical difference which diminishes at 480 K.

Composition, structural, and thermal analysis of cellulose, hemicellulose, and lignin of reconstituted cut stems in tobacco

In order to encourage effective recycling of tobacco resources in the industry and successfully enhance the quality of reconstituted cut stems (GS30). This study investigates the thermal, structural, and material composition of GS30. It was found that compared with high-quality tobacco leaves and cut stems, the contents of important macromolecules including cellulose, hemicellulose and lignin in GS30 were 21.74 ± 1.14 %, 3.66 ± 0.56 %, and 1.69 ± 0.46 % respectively. Its content is smaller than that of blank cut stems but similar to high-quality tobacco leaves. The important macromolecular structures were further analyzed for their surface morphology and crystal structure using FTIR, XRD, SAXS, and SEM. After analyzing the thermal cracking behavior of GS30 through PY-GC-MS, it was found that GS30 has four weight loss stages and thermal cracking releases near 30 types of aroma substances, showing obvious advantages in releasing aromatic gases. This demonstrates that the structure of GS30 obtained from secondary processing of discarded tobacco leaves is loose and easy to burn and decompose, which can effectively reduce the release of cigarette tar.

Combining Fourier-transform infrared spectroscopy and multivariate analysis for chemotyping of cell wall composition in Mungbean (Vigna radiata (L.) Wizcek)

BackgroundDissection of complex plant cell wall structures demands a sensitive and quantitative method. FTIR is used regularly as a screening method to identify specific linkages in cell walls. However, quantification and assigning spectral bands to particular cell wall components is still a major challenge, specifically in crop species. In this study, we addressed these challenges using ATR-FTIR spectroscopy as it is a high throughput, cost-effective and non-destructive approach to understand the plant cell wall composition. This method was validated by analysing different varieties of mungbean which is one of the most important legume crops grown widely in Asia.ResultsUsing standards and extraction of a specific component of cell wall components, we assigned 1050–1060 cm−1 and 1390–1420 cm−1 wavenumbers that can be widely used to quantify cellulose and lignin, respectively, in Arabidopsis, Populus, rice and mungbean. Also, using KBr as a diluent, we established a method that can relatively quantify the cellulose and lignin composition among different tissue types of the above species. We further used this method to quantify cellulose and lignin in field-grown mungbean genotypes. The ATR-FTIR-based study revealed the cellulose content variation ranges from 27.9% to 52.3%, and the lignin content variation ranges from 13.7% to 31.6% in mungbean genotypes.ConclusionMultivariate analysis of FT-IR data revealed differences in total cell wall (600–2000 cm−1), cellulose (1000–1100 cm−1) and lignin (1390–1420 cm−1) among leaf and stem of four plant species. Overall, our data suggested that ATR-FTIR can be used for the relative quantification of lignin and cellulose in different plant species. This method was successfully applied for rapid screening of cell wall composition in mungbean stem, and similarly, it can be used for screening other crops or tree species.

Systems genetic analysis of lignin biosynthesis in Populus tremula.

The genetic control underlying natural variation in lignin content and composition in trees is not fully understood. We performed a systems genetic analysis to uncover the genetic regulation of lignin biosynthesis in a natural 'SwAsp' population of aspen (Populus tremula) trees. We analyzed gene expression by RNA sequencing (RNA-seq) in differentiating xylem tissues, and lignin content and composition using Pyrolysis-GC-MS in mature wood of 268 trees from 99 genotypes. Abundant variation was observed for lignin content and composition, and genome-wide association study identified proteins in the pentose phosphate pathway and arabinogalactan protein glycosylation among the top-ranked genes that are associated with these traits. Variation in gene expression and the associated genetic polymorphism was revealed through the identification of 312 705 local and 292 003 distant expression quantitative trait loci (eQTL). A co-expression network analysis suggested modularization of lignin biosynthesis and novel functions for the lignin-biosynthetic CINNAMYL ALCOHOL DEHYDROGENASE 2 and CAFFEOYL-CoA O-METHYLTRANSFERASE 3. PHENYLALANINE AMMONIA LYASE 3 was co-expressed with HOMEOBOX PROTEIN 5 (HB5), and the role of HB5 in stimulating lignification was demonstrated in transgenic trees. The systems genetic approach allowed linking natural variation in lignin biosynthesis to trees´ responses to external cues such as mechanical stimulus and nutrient availability.

Effects of alkali-soluble hemicellulose separation on the structure of bamboo lignin and lignin-carbohydrate complexes

In this study, alkali treatment was used to preferentially separate hemicellulose, and the structural changes of lignin and lignin-carbohydrate complexes (LCC) in the residual bamboo solids were investigated. The chemical composition and structural characteristics of lignin and LCC were analyzed. After alkali treatment, the monosaccharide content in bamboo lignin decreased from 7.62 % to 2.90 % compared to the raw material. The obtained lignin exhibited higher purity and larger molecular weight, with the macromolecular lignin linked by β-O-4′ bonds remaining almost undegraded. After alkali treatment, the linkage bonds in the Björkman LCC were composed of phenyl glycoside (PhGlc), and the bond in LCC-AcOH consisted of benzyl ether (BE). The results showed that the preferential extraction of hemicellulose preserved the biopolymer structure of lignin in bamboo, thereby providing an important basis for the comprehensive separation and utilization of bamboo components.

Combined pretreatment of malic acid and kraft pulping for the production of fermentable sugars and highly active lignin

The separation and utilization of cellulose, hemicellulose, and lignin in lignocellulosic biorefineries present significant challenges. This study proposes a pretreatment method for biomass refining by combining acid and kraft pulping. Firstly, the biomass was pretreated by malic acid, resulting in the isolation of xylo-oligosaccharides (XOS) with a yield of 86.26 % with optimized conditions of 180 °C, 1 wt% concentration, 40 min. Secondly, a mixture of 12.98 wt% NaOH and 1.043 wt% Na2S is employed to achieve lignin removal efficiency up to 63.42 %. Physical refinement techniques are then applied to enhance the enzyme digestion efficiency of cellulose, resulting in an increase from 55.03 % to 91.4 % for efficient cellulose conversion. The reacted samples exhibit a lignin composition rich in β-O-4 ether bonds, facilitating their high-value utilization. The results indicated that the combined pretreatment approach demonstrates high efficiency in separating cellulose, hemicellulose, and lignin while obtaining XOS, highly active lignin, and enzyme-digested substrates.

Study on the characteristics of novel fiber extracted from Foxtail palm fruits – A steps towards the sustainable development

This study explores the properties of fibers extracted from the fruits of the Foxtail palm (FPF) and assesses their potential for advancing sustainable development. Antibacterial assays demonstrated that these fibers significantly inhibit the growth of gram-negative bacteria, including Pseudomonas aeruginosa and Salmonella enterica, with inhibition zones of 24 mm and 30 mm, respectively. X-ray diffraction analysis revealed a predominantly crystalline structure, which is crucial for use as reinforcing materials, showing distinct peaks at 20° and 30° diffraction angles that signify the presence of cellulose I. Fourier-transform infrared spectroscopy confirmed the fibers’ complex composition of cellulose, hemicellulose, and lignin, indicated by the presence of hydroxyl, carbonyl, and aliphatic functional groups. Scanning electron microscopy analysis showed a rough and irregular surface texture adorned with numerous microfibrils and cavities, which are beneficial for mechanical interlocking with polymer matrices. The densely arranged cellulose microfibrils, approximately 210 µm in diameter, lend the fibers high tensile strength and stiffness. Although some surface imperfections were observed, the inherent porosity of the fibers facilitates resin absorption, enhancing their reinforcement capabilities in composite materials.

PERFORMANCE OF SOKOTO RED GOAT FED UREA TREATED GROUNDNUT (ARACHIS HYPOGAEA) SHELL

The study that assessed the impact of treatment of groundnut shell on performance, nutrient digestibility, and nitrogen utilization by Sokoto red goats was carried out at Professor Lawal Abdu Saulawa Livestock Teaching and Research Farm, Federal University Dustin-Ma, Katsina State. Fifteen growing male goats used for the experiment were allotted to three treatments at five for each treatment in a Completely Randomized Design (CRD) with each one serving as a replicate. The experiment comprised of three treatments namely T1, T2 and T3 at inclusion levels of urea treated GNS at 0%, 10% and 20% respectively. The feeding trial was carried out for 84 days. Growth, digestibility, and nitrogen utilization parameters were measured. The proximate analysis revealed slight increase in crude protein while crude fibre decreased with increased level of inclusion of GNS. Lignin composition also slightly reduced from 11.90% in T1 to 10.90% (T3). There were significant differences (P<0.05) in weight gain per day, daily feed intake and feed efficiency. Average daily weight gain (75g/day) and feed efficiency (0.15) were higher in treatment T3 than those of other treatments but with lower average dry matter intake (490.83g/day). The nitrogen intake, faecal nitrogen, urine nitrogen, nitrogen absorbed, nitrogen balance, and nitrogen retained were significantly different (P<0.05) across the treatments. Treatment T3 which contained 20% inclusion level of UGNS was the best among all the diets because it contained 86.90% CPD, 95.66% EED, 92.76%, CFD 17.45%, 14.27 g/day nitrogen balance and 81.82% nitrogen retention. The feed cost per kg liveweight gain was significantly less (P<0.05) in treatment T3. The conclusion of the study was that treatment T3, which contained 20% urea treated GNS performed better than others.

Quantitative and Structural Characterization of Native Lignin in Hardwood and Softwood Bark via Solid-State NMR Spectroscopy.

A major factor limiting bark's industrial use is its greater recalcitrance compared to wood. While lignin is widely recognized as a significant contributor, precise characterization of lignin in bark remains sparse, presenting a crucial gap that impedes understanding of its impact. In this study, we employed advanced solid-state nuclear magnetic resonance (NMR) spectroscopy to analyze bark samples from various species, including willow, poplar, and pine. We established and verified that lignin methoxy peak at 56 ppm serves as a reliable quantitative metric to assess lignin content, with which we calculated the lignin contents in bark are significantly reduced by more than 70% compared to those in wood. Furthermore, in situ characterization revealed significant reduction of β-ether linkage in bark lignin across species, revealing a more condensed and resistant structural configuration. Our results have substantially advanced our comprehension of the composition and structure of native lignin in tree bark.

A green and efficient approach for the simultaneous extraction and mechanisms of essential oil and lignin from Cinnamomum camphora: Process optimization based on deep learning

The utilization and economic benefits of biomass resources can be maximized through rational design and process optimization. In this study, an innovative approach for the simultaneous extraction of essential oil and lignin from Cinnamomum camphora leaves by deep eutectic solvent (DES) and optimization of the process parameters was achieved using deep learning tools. With the water content of 40 %, liquid-solid ratio of 9.00 mL/g, and distillation time of 51.81 min, the yields of the essential oil and lignin reached 3.15 ± 0.02 % and 9.75 ± 0.15 %, respectively. Notably, the efficiency of simultaneous extraction of essential oil improved by 23 % compared to that of traditional steam distillation. Moreover, the extraction mechanism of the process was clarified. The connection between lignin with cellulose and hemicellulose was disintegrated by the DES, resulting in lignin shedding and hence accelerating the dissolution of essential oil. Moreover, the compositions of lignin and essential oil were also identified.