Sustainable lignin and lignin-derived compounds as potential therapeutic agents for degenerative orthopaedic diseases: A systemic review

Preparation of quaternary ammonium lignosulfonate modified UV resistant polyurethane and its application in leather dyeing

Applying cationic waterborne polyurethane (CWPU) in the leather color-fixing process can improve the dyeing rate and enhance color fastness. However, under prolonged exposure to sunlight, CWPU will age and degrade and the leather will fade in color, become stiff and crack easily. In this study, an Ultraviolet absorber was introduced into cationic waterborne polyurethane (UVCWPU) and quaternary ammonium Lignosulfonate (QLS) was prepared by quaternization. Quaternary ammonium Lignosulfonate/UV-resistant waterborne polyurethane (QLS/UVCWPU) composite was prepared by the blending method. A one-way experiment was carried out to investigate the effect of the additional amount of quaternary ammonium reagent on the degree of modification of QLS, and the results showed that when the ratio of 3-chloro-2-hydroxypropyltrimethylammonium chloride (CHPTMAC) to LS was 7:1, the isoelectric point of the prepared QLS reached 6.65, and the content of N was 4.32 % so that the quaternary ammonium lignosulfonate modification was successful. QLS/UVCWPU was used to solidify the leather at pH 4.0 and a dosage of 4 %. The dye absorption rate of the leather increased to 97.3 %, the K/S value of the dyed gray leather reached 28.51, the color fastness to dry rubbing was improved to grade 5, and the color fastness to wet rubbing was up to grade 3 and enhancing the color fastness to sunlight, slowing down the effect of ultraviolet aging, and improving the antimicrobial properties of the leather.

Switchable Solvent for Separation and Extraction of Lignin from Lignocellulose Biomass: An Investigation of Chemical Structure and Molecular Weight

Lignin, the most abundant natural aromatic polymer, holds considerable promise for applications in various industries. The primary obstacle to the valorization of lignin into useful materials is its low molecular weight and diminished chemical reactivity, attributable to its intricate structure. This study aimed to treat lignocellulosic biomass using a switchable solvent (DBU-HexOH/H2O) derived from the non-nucleophilic superbase 1,8-diazabicyclo [5.4.0]undec-7-ene (DBU), which efficiently separates and extracts lignin from poplar wood. Additionally, it sought to characterize fundamental properties of the extracted switchable solvent lignin (SSL) and propose a mechanism for its separation. In comparison to milled wood lignin, SSL exhibits a greater molecular weight, superior homogeneity, and enhanced stability. The SSL sample was analyzed using spectroscopies including infrared spectroscopy, nuclear magnetic resonance, and X-ray photoelectron spectroscopy. The findings indicated that the structure of SSL was preserved, with the switchable solvent primarily cleaving the C-C and α-O-4 bonds, resulting in a low hydroxyl content, an elevated H/C ratio, and a reduced O/C ratio. The SSL was successfully prepared to lignin nanoparticles (LNPs) with size range of 531-955 nm. This paper presents a technique for processing lignocellulosic biomass using a switchable solvent, highlighting advancements in lignin's structure and enhancing its use in the chemical sector.

Systematic Characteristics of Fucoidan: Intriguing Features for New Pharmacological Interventions

Fucoidan, a sulfated polysaccharide found primarily in brown algae, is known for exhibiting various biological activities, many of which have been attributed to its sulfate content. However, recent advancements in techniques for analyzing polysaccharide structures have highlighted that not only the sulfate groups but also the composition, molecular weight, and structures of the polysaccharides and their monomers play a crucial role in modulating biological effects. This review comprehensively provides the monosaccharide composition, degree of sulfation, molecular weight distribution, and linkage of glycosidic bonds of fucoidan, focusing on the diversity of its biological activities based on various characteristics. The implications of these findings for future applications and potential therapeutic uses of fucoidan are also discussed.

A review on gold nanoparticles as an innovative therapeutic cue in bone tissue engineering: Prospects and future clinical applications

Bone damage is a complex orthopedic problem primarily caused by trauma, cancer, or bacterial infection of bone tissue. Clinical care management for bone damage remains a significant clinical challenge and there is a growing need for more advanced bone therapy options. Nanotechnology has been widely explored in the field of orthopedic therapy for the treatment of a severe bone disease. Among nanomaterials, gold nanoparticles (GNPs) along with other biomaterials are emerging as a new paradigm for treatment with excellent potential for bone tissue engineering and regenerative medicine applications. In recent years, a great deal of research has focused on demonstrating the potential for GNPs to provide for enhancement of osteogenesis, reduction of osteoclastogenesis/osteomyelitis, and treatment of bone cancer. This review details the latest understandings in regards to GNPs based therapeutic systems, mechanisms, and the applications of GNPs against various bone disorders. The present review aims to summarize i) the mechanisms of GNPs in bone tissue remodeling, ii) preparation methods of GNPs, and iii) functionalization of GNPs and its decoration on biomaterials as a delivery vehicle in a specific bone tissue engineering for future clinical application.

Research trends of bio-application of major components in lignocellulosic biomass (cellulose, hemicellulose and lignin) in orthopedics fields based on the bibliometric analysis: A review

Cellulose, hemicellulose, and lignin are the major bio-components in lignocellulosic biomass (BC-LB), which possess excellent biomechanical properties and biocompatibility to satisfy the demands of orthopedic applications. To understand the basis and trends in the development of major bio-components in BC-LB in orthopedics, the bibliometric technology was applied to get unique insights based on the published papers (741) in the Web of Science (WOS) database from January 1st, 2001, to February 14th, 2023. The analysis includes the annual distributions of publications, keywords co-linearity, research hotspots exploration, author collaboration networks, published journals, and clustering of co-cited literature. The results reveal a steady growth in publications focusing on the application of BC-LB in orthopedics, with China and the United States leading in research output. The "International Journal of Biological Macromolecules" was identified as the most cited journal for BC-LB research in orthopedics. The research hotspots encompassed bone tissue engineering, cartilage tissue engineering, and drug delivery systems, indicating the fundamental research and potential development in these areas. This study also highlights the challenges associated with the clinical application of BC-LB in orthopedics and provides valuable insights for future advancements in the field.

Fractional extraction of lignin from coffee beans with low cytotoxicity, excellent anticancer and antioxidant activities

Lignin, a biopolymer generated from renewable resources, is widely present in terrestrial plants and possesses notable biosafety characteristics. The objective of this work was to assess the edible safety, in vitro antioxidant, and anti-cancer properties of various lignin fractions isolated from commercially available coffee beans often used for coffee preparation. The findings suggest that the phenolic hydroxyl content increased from 3.26 mmol/g (ED70L) to 5.81 mmol/g (ED0L) with decreasing molecular weight, which resulted in more significant antioxidant properties of the low molecular weight lignin fraction. The findings of the study indicate that the viability of RAW 264.7 and HaCaT cells decreased as the quantity of lignin fractions increased. It was observed that concentrations below 200 μg/mL did not exhibit any harmful effects on normal cells. The results of the study demonstrated a significant reduction of cancer cell growth (specifically A375 cells) at a concentration of 800 μg/mL for all lignin fractions, with an observed inhibition rate of 95 %. The results of this study indicate that the lignin extracts derived from coffee beans exhibit significant potential in mitigating diseases resulting from excessive radical production. Furthermore, these extracts show promise as natural antioxidants and anti-cancer agents.

Polyphenols as potential preventers of osteoporosis: A comprehensive review on antioxidant and anti-inflammatory effects, molecular mechanisms, and signal pathways in bone metabolism

Osteoporosis (OP) is a skeletal disorder characterized by decreased bone density, alterations in bone microstructure, and increased damage to the bones. As the population ages and life expectancy increases, OP has become a global epidemic, drawing attention from scientists and doctors. Because of polyphenols have favorable antioxidant and anti-allergy effects, which are regarded as potential methods to prevent angiocardipathy and OP. Polyphenols offer a promising approach to preventing and treating OP by affecting bone metabolism, reducing bone resolution, maintaining bone density, and lowering the differentiation level of osteoclasts (OC). There are multiple ways in which polyphenols affect bone metabolism. This article provides an overview of how polyphenols inhibit oxidative stress, exert antibacterial effects, and prevent the occurrence of OP. Furthermore, we will explore the regulatory mechanisms and signaling pathways implicated in this process.

Recent advances in lignin antioxidant: Antioxidant mechanism, evaluation methods, influence factors and various applications

Lignin, a by-product of processing lignocellulosic materials, has a polyphenolic structure and can be used as an antioxidant directly or synergistically with synthetic types of antioxidants, leading to different applications. Its antioxidant mechanism is mainly related to the production of ROS, but the details need to be further investigated. The antioxidant property of lignin is mainly related to the content of phenolic hydroxyl group, but methoxy, purity will also have an effect on it. In addition, different methods to detect the antioxidant properties of lignin have different advantages and disadvantages. In this paper, the antioxidant mechanism of lignin, the methods to determine the antioxidant activity and the progress of its application in various fields are reviewed. In addition, the current research on the antioxidant properties of lignin and the hot directions are provided, and an outlook on the research into the antioxidant properties of lignin is provided to broaden its potential application areas.

Sustainable Biomass Lignin-Based Hydrogels: A Review on Properties, Formulation, and Biomedical Applications

Different techniques have been developed to overcome the recalcitrant nature of lignocellulosic biomass and extract lignin biopolymer. Lignin has gained considerable interest owing to its attractive properties. These properties may be more beneficial when including lignin in the preparation of highly desired value-added products, including hydrogels. Lignin biopolymer, as one of the three major components of lignocellulosic biomaterials, has attracted significant interest in the biomedical field due to its biocompatibility, biodegradability, and antioxidant and antimicrobial activities. Its valorization by developing new hydrogels has increased in recent years. Furthermore, lignin-based hydrogels have shown great potential for various biomedical applications, and their copolymerization with other polymers and biopolymers further expands their possibilities. In this regard, lignin-based hydrogels can be synthesized by a variety of methods, including but not limited to interpenetrating polymer networks and polymerization, crosslinking copolymerization, crosslinking grafted lignin and monomers, atom transfer radical polymerization, and reversible addition-fragmentation transfer polymerization. As an example, the crosslinking mechanism of lignin-chitosan-poly(vinyl alcohol) (PVA) hydrogel involves active groups of lignin such as hydroxyl, carboxyl, and sulfonic groups that can form hydrogen bonds (with groups in the chemical structures of chitosan and/or PVA) and ionic bonds (with groups in the chemical structures of chitosan and/or PVA). The aim of this review paper is to provide a comprehensive overview of lignin-based hydrogels and their applications, focusing on the preparation and properties of lignin-based hydrogels and the biomedical applications of these hydrogels. In addition, we explore their potential in wound healing, drug delivery systems, and 3D bioprinting, showcasing the unique properties of lignin-based hydrogels that enable their successful utilization in these areas. Finally, we discuss future trends in the field and draw conclusions based on the findings presented.

Comparison of structure and neuroprotective ability of low molecular weight galactomannans from Sesbania cannabina obtained by different extraction technologies

Low-molecular-weight-galactomannan (LMW-GM) is an edible polysaccharide with various biological activities. However, it is used in the field of neuroprotection. In this study, two types of LMW-GMs from Sesbania cannabina were obtained by gluconic acid extraction (GA-LMW-GM) and enzymatic hydrolysis (GMOS). The structure of GA-LMW-GM and GMOS were identified using different nuclear magnetic resonance (NMR) techniques. The antioxidant and neuroprotective activities of GA-LMW-GM and GMOS were evaluated in vitro/vivo. The results showed that both GA-LMW-GM and GMOS possess good free radicals scavenging ability in vitro with IC₅₀ values of 1.9 mg/mL and 4.9 mg/mL for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals 2.8 mg/mL and 4.4 mg/mL for O₂^•- radicals, respectively. However, GA-LMW-GM was more effective at scavenging reactive oxygen species (ROS) in vivo and protecting the fundamental growth (with a recovery capability of 62.5%) and locomotor functions (with recovery capability of 193.7%) of zebrafish with neurological damage induced by Bisphenol AF.

Engineered extracellular vesicles as therapeutics of degenerative orthopedic diseases

Degenerative orthopedic diseases, as a global public health problem, have made serious negative impact on patients' quality of life and socio-economic burden. Traditional treatments, including chemical drugs and surgical treatments, have obvious side effects and unsatisfactory efficacy. Therefore, biological therapy has become the focus of researches on degenerative orthopedic diseases. Extracellular vesicles (EVs), with superior properties of immunoregulatory, growth support, and drug delivery capabilities, have emerged as a new cell-free strategy for the treatment of many diseases, including degenerative orthopedic diseases. An increasing number of studies have shown that EVs can be engineered through cargo loading, surface modification, and chemical synthesis to improve efficiency, specificity, and safety. Herein, a comprehensive overview of recent advances in engineering strategies and applications of engineered EVs as well as related researches in degenerative orthopedic diseases, including osteoarthritis (OA), osteoporosis (OP), intervertebral disc degeneration (IDD) and osteonecrosis of the femoral head (ONFH), is provided. In addition, we analyze the potential and challenges of applying engineered EVs to clinical practice.

The acceleration on decolorization of azo dyes by magnetic lignin-based materials via enhancing the extracellular electron transfer

Two novel and eco-friendly redox mediators (RMs), magnetic oxidative vanillin (MOV) and magnetic oxidative syringaldehyde (MOS), both derived from lignin, were prepared to improve the decolorization of the methyl orange (MO) dye. The Decolorization Efficiency (DE) of MO in the batch experiments with MOV and MOS were increased by more than 60% and 22%, respectively, when compared to the control experiment without magnetic RMs. Moreover, the two magnetic RMs could maintain stable DE of MO in sequenced batch reactors (SBRs), and negligible leaching of the oxidized lignin monomers was observed under various environmental conditions. Density Function Theory (DFT) calculations were used to propose three potential biodegradation mechanisms for azo dyes, and the key intermediates were confirmed using high-performance liquid chromatography. This study proposed a feasible strategy for functional utilization of lignin resource, as well as a practical method for effectively treating azo dye-containing wastewater.

Designing Lignin-Based Biomaterials as Carriers of Bioactive Molecules

There is a need to develop circular and sustainable economies by utilizing sustainable, green, and renewable resources in high-tech industrial fields especially in the pharmaceutical industry. In the last decade, many derivatives of food and agricultural waste have gained considerable attention due to their abundance, renewability, biocompatibility, environmental amiability, and remarkable biological features. Particularly, lignin, which has been used as a low-grade burning fuel in the past, recently attracted a lot of attention for biomedical applications because of its antioxidant, anti-UV, and antimicrobial properties. Moreover, lignin has abundant phenolic, aliphatic hydroxyl groups, and other chemically reactive sites, making it a desirable biomaterial for drug delivery applications. In this review, we provide an overview of designing different forms of lignin-based biomaterials, including hydrogels, cryogels, electrospun scaffolds, and three-dimensional (3D) printed structures and how they have been used for bioactive compound delivery. We highlight various design criteria and parameters that influence the properties of each type of lignin-based biomaterial and corelate them to various drug delivery applications. In addition, we provide a critical analysis, including the advantages and challenges encountered by each biomaterial fabrication strategy. Finally, we highlight the prospects and future directions associated with the application of lignin-based biomaterials in the pharmaceutical field. We expect that this review will cover the most recent and important developments in this field and serve as a steppingstone for the next generation of pharmaceutical research.

Improving the protective ability of lignin against vascular and neurological development in BPAF-induced zebrafish by high-pressure homogenization technology

The lack of a sufficient amount of functional groups in the lignin structure limits its bioapplication. In this work, high-pressure homogenization was performed on original kraft lignin (L-ORI) to prepare lignin nanoparticles (L-NANO), which aimed to improve its functional group contents for further vascular and neurological applications. The results showed that the prepared L-NANO possessed spherical structures with diameters of 40.3-160.4 nm and increased amount of hydroxyl groups. Compared to L-ORI, L-NANO possessed better in vivo and in vitro antioxidant capacity, which could endow it with enhanced protective effects for the vascular and neural development of bisphenol AF (BPAF)-induced zebrafish. In addition, L-NANO reduced the neurotoxicity and cardiovascular toxicity of BPAF in zebrafish by upregulating the expression levels of oxidative stress-related genes (Cu/Zn-Sod and cat), which could further significantly upregulate the expression levels of neurogenesis genes (elavl3, gap43, mbp, and syn2a) and protect the contraction of the cardinal vein (CCV) and early central nervous system development by upregulating the expression levels of vascular genes (flk1 and flt4). The excellent cardiovascular and neurodevelopmental protective ability of L-NANO indicated that high-pressure homogenization is a promising technology for improving the bioactivity of lignin.

Extraction and purification of antioxidative flavonoids from Chionanthus retusa leaf

In this work, flavonoids from the leaves of Chionanthus retusa were extracted using alcohol, and the extraction yield was optimized by single-factor and orthogonal experiments. Then, the extracted solution with flavonoids was purified via macroporous resin by elution with different concentrations of ethanol. The antioxidative activity of total flavonoid in purified extracted solution was evaluated by detecting its ability to scavenge DPPH free radicals. The results demonstrated that ethanol with a concentration of 60%, ultrasonic power of 140 W, liquid-solid ratio of 25:1 ml g^-1, and water-bath temperature of 80°C were the optimal conditions for the extraction of total flavonoids from C. retusa leaf, achieving a yield of 121.28 mg g^-1. After purification by macroporous resin using different concentrations of ethanol, the highest content of total flavonoids (88.51%) in the extracted solution can be obtained with the 50% ethanol eluant. The results of scavenging DPPH free radicals suggest that the purified flavonoids in the 50% ethanol eluant had the best antioxidant capacity over the flavonoids in other ethanol eluants. In addition, it is confirmed the antioxidant capacity of the extractives was associated with the content of total flavonoids and kinds of flavonoids. These results may provide a feasible pathway to make full use of total flavonoids from C. retusa leaf.

Jasminum sambac Cell Extract as Antioxidant Booster against Skin Aging

Oxidative stress plays a major role in the skin aging process through the reactive oxygen species production and advanced glycation end products (AGEs) formation. Antioxidant ingredients are therefore needed in the skin care market and the use of molecules coming from plant cell cultures provide a unique opportunity. In this paper, the features of an hydroethanolic extract obtained by Jasminum sambac cells (JasHEx) were explored. The antioxidant and anti-AGE properties were investigated by a multidisciplinary approach combining mass spectrometric and bio-informatic in vitro and ex vivo experiments. JasHEx contains phenolic acid derivatives, lignans and triterpenes and it was found to reduce cytosolic reactive oxygen species production in keratinocytes exposed to exogenous stress. It also showed the ability to reduce AGE formation and to increase the collagen type I production in extracellular matrix. Data demonstrated that JasHEx antioxidant properties were related to its free radical scavenging and metal chelating activities and to the activation of the Nrf2/ARE pathway. This can well explain JasHEx anti-inflammatory activity related to the decrease in NO levels in LPS-stimulated macrophages. Thus, JasHEx can be considered a powerful antioxidant booster against oxidative stress-induced skin aging.

Recovery of Lignins with Potent Antioxidant Properties from Shells of Edible Nuts by a Green Ball Milling/Deep Eutectic Solvent (DES)-Based Protocol

Lignins are phenolic polymers endowed with potent antioxidant properties that are finding increasing applications in a variety of fields. Consequently, there is a growing need for easily available and sustainable sources, as well as for green extraction methodologies of these compounds. Herein, a ball milling/deep eutectic solvent (DES)-based treatment is reported as an efficient strategy for the recovery of antioxidant lignins from the shells of edible nuts, namely chestnuts, hazelnuts, peanuts, pecan nuts, and pistachios. In particular, preliminarily ball-milled shells were treated with 1:2 mol/mol choline chloride:lactic acid at 120 °C for 24 h, and the extracted material was recovered in 19–27% w/w yields after precipitation by the addition of 0.01 M HCl. Extensive spectroscopic and chromatographic analysis allowed for confirmation that the main phenolic constituents present in the shell extracts were lignins, accompanied by small amounts (0.9% w/w) of ellagic acid, in the case of chestnut shells. The recovered samples exhibited very promising antioxidant properties, particularly in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay (EC₅₀ values ranging from 0.03 to 0.19 mg/mL). These results open new perspectives for the valorization of nut shells as green sources of lignins for applications as antioxidants, e.g., in the biomedical, food, and/or cosmetic sector.

Surface chemistry and bioactivity of colloidal particles from industrial kraft lignins

The morphology control of lignin through particle size reduction to nanoscale seems to be a suitable conversion technology to overcome the intrinsic limitations of its native form to develop a wide range of biomaterials with high performance. Colloidal lignin particles (CLPs) in the range of 150-200 nm were synthesised from hardwood and softwood kraft lignins by the solvent shifting method. The initial molecular features of kraft lignins were evaluated in terms of purity, molecular weight distribution, and chemical functionalities. The impact of the lignin source and structure on the morphology, size distribution, and surface chemistry of CLPs was evaluated by particle size analyser, SEM, TEM and ¹H NMR. The results evidenced the influence of the botanical origin on the morphology and surface chemistry of particles. Furthermore, the antioxidant properties and cytotoxicity of lignins and corresponding CLPs, towards lung fibroblast cells were compared. CLPs from hardwood kraft lignins exhibited higher antioxidant power against DPPH free radical and a higher cytotoxic effect (IC₃₀ = 67-70 μg/mL) against lung fibroblast when compared to CLPs from softwood kraft lignin (IC₃₀ = ~91 μg/mL). However, the cytotoxicity of these biomaterials was dose-dependent, suggesting their potential application as active ingredients in cosmetic and pharmaceutic products at low concentrations.

Valorization of bamboo shoot shell waste for the coproduction of fermentable sugars and xylooligosaccharides

In this work, hydrothermal pretreatment (autohydrolysis) was coupled with endo-xylanase enzymatic hydrolysis for bamboo shoot shell (BSS) to produce glucose and valuable xylooligosaccharides (XOS) rich in xylobiose (X2) and xylotriose (X3). Results showed that the enzymatic hydrolysis efficiency of pretreated BSS residue reached 88.4% with addition of PEG during the hydrolysis process. To enrich the portions of X2–X3 in XOS, endo-xylanase was used to hydrolyze the XOS in the prehydrolysate, which was obtained at the optimum condition (170°C, 50 min). After enzymatic hydrolysis, the yield of XOS reached 25.6%, which contained 76.7% of X2–X3. Moreover, the prehydrolysate contained a low concentration of fermentation inhibitors (formic acid 0.7 g/L, acetic acid 2.6 g/L, furfural 0.7 g/L). Based on mass balance, 32.1 g of glucose and 6.6 g of XOS (containing 5.1 g of X2-X3) could be produced from 100.0 g of BSS by the coupled technology. These results indicate that BSS could be an economical feedstock for the production of glucose and XOS.

Synthesis, determination, and bio-application in cellular and biomass-bamboo imaging of natural cinnamaldehyde derivatives

Cinnamon essential oil (CEO) is the main ingredient in the renewable biomass of cinnamon, which contains natural cinnamaldehyde. To valorize the value of cinnamaldehyde, two simple and useful compounds (1 and 2) from CEO were synthesized using a Schiff-base reaction and characterized by infrared spectra (IR), nuclear magnetic resonance (NMR), and high-resolution mass spectrometry (HRMS). Compound 1 was used to confirm the presence of Fe³⁺ and ClO⁻ in solution, as well as compound 2. Using fluorescence enhancement phenomena, it offered practicable linear relationship of 1’s fluorescence intensity and Fe³⁺ concentrations: (0–8.0 × 10⁻⁵ mol/L), y = 36.232x + 45.054, R² = 0.9947, with a limit of detection (LOD) of 0.323 μM, as well as compound 2. With increasing fluorescence, F₄₀₄/F₄₂₆ of 1 and the ClO⁻ concentration (0–1.0 × 10⁻⁴ mol/L) also had a linear relationship: y = 0.0392x + 0.5545, R² = 0.9931, LOD = 0.165 μM. However, the fluorescence intensity of 2 (596 nm) was quenched by a reduced concentration of ClO⁻, resulting in a linear. In addition, compounds 1 and 2 were used to image human astrocytoma MG (U-251), brain neuroblastoma (LN-229) cells, and bamboo tissue by adding Fe³⁺ or ClO⁻, with clear intracellular fluorescence. Thus, the two compounds based on CEO could be used to dye cells and bamboo tissues by fluorescence technology.

Lignin-carbohydrate complexes suppress SCA3 neurodegeneration via upregulating proteasomal activities

Lignin-carbohydrate complexes (LCCs) represent a group of macromolecules with diverse biological functions such as antioxidative properties. Polyglutamine (polyQ) diseases such as spinocerebellar ataxia type 3 (SCA3) comprise a set of neurodegenerative disorders characterized by the formation of polyQ protein aggregates in patient neurons. LCCs have been reported to prevent such protein aggregation. In this study, we identified a potential mechanism underlying the above anti-protein aggregation activity. We isolated and characterized multiple LCC fractions from bamboo and poplar and found that lignin-rich LCCs (BM-LCC-AcOH and PR-LCC-AcOH) effectively eliminated both monomeric and aggregated mutant ataxin-3 (ATXN3polyQ) proteins in neuronal cells and a Drosophila melanogaster SCA3 disease model. In addition, treatment with BM-LCC-AcOH or PR-LCC-AcOH rescued photoreceptor degeneration in vivo. At the mechanistic level, we demonstrated that BM-LCC-AcOH and PR-LCC-AcOH upregulated proteasomal activity. When proteasomal function was impaired, the ability of the LCCs to suppress ATXN3polyQ aggregation was abolished. Thus, we identified a previously undescribed proteasome-inducing function of LCCs and showed that such activity is indispensable for the beneficial effects of LCCs on SCA3 neurotoxicity.