Bioactive Lyocell Fibers with Inherent Antibacterial, Antiviral and Antifungal Properties.

Functional Lyocell fibers gain interest in garments and technical textiles, especially when equipped with inherently bioactive features. In this study, Lyocell fibers are modified with an ion exchange resin and subsequently loaded with copper (Cu) ions. The modified Lyocell process enables high amounts of the resin additive (>10%) through intensive dispersion and subsequently, high uptake of 2.7% Cu throughout the whole cross-section of the fiber. Fixation by Na2CO3 increases the washing and dyeing resistance considerably. Cu content after dyeing compared to the original fiber value amounts to approx. 65% for reactive, 75% for direct, and 77% for HT dyeing, respectively. Even after 50 household washes, a recovery of 43% for reactive, 47% for direct and 26% for HT dyeing is proved. XRD measurements reveal ionic bonding of Cu fixation inside the cellulose/ion exchange resin composite. A combination of the fixation process with a change in Cu valence state by glucose/NaOH leads to the formation of Cu2O crystallites, which is proved by XRD. Cu fiber shows a strong antibacterial effect against Staphylococcus aureus and Klebsiella pneumonia bacteria, even after 50 household washing cycles of both >5 log CFU. In nonwoven blends with a share of only 6% Cu fiber, a strong antimicrobial (CFU > log 5) and full antiviral effectiveness (>log 4) was received even after 50 washing cycles. Time-dependent measurements already show strong antiviral behavior after 30 s. Further, the fibers show an increased die off of the fungal isolate Candida auris with CFU log 4.4, and nonwovens made from 6% Cu fiber share a CFU log of 1.7. Findings of the study predestines the fiber for advanced textile processing and applications in areas with high germ loads.

Doxorubicin encapsulated blend of sitagliptin-lignin polymeric drug delivery system for effective combination therapy against cancer.

In this research, a sitagliptin-lignin biopolymer (SL) containing zinc selenide quantum dots (ZnSe QDs) and doxorubicin (doxo) was synthesized. The fabricated polymeric drug delivery system was characterized via FTIR, XRD, SEM, TGA, IR, and DSC. SLQD-Doxo exhibited an irregular surface with a 32 nm diameter and well-defined surface chemistry. Drug loading efficiency was assessed at different concentrations, pH levels, time intervals, and temperatures, and drug kinetics were calculated. Maximum drug release was observed at 6 µmol concentration after 24 h, pH of 6.5 and 45 °C. The maximum drug encapsulation efficiency was 81.75 %. SLQD-Doxo demonstrated 24.4 ± 1.04 % anti-inflammatory activity, and the maximum lipoxygenase inhibition in a concentration-dependent manner was 71.45 ± 2.02 %, compared to indomethacin, a standard anticancer drug. The designed system was applied to breast cancer MCF-7 cells to evaluate anticancer activity. Cytotoxicity of SLQD-Doxo resulted in 24.48 ± 1.64 dead cells and 74.39 ± 4.12 viable cells. Lignin's polyphenolic nature resulted in good antioxidant activity of LLQD-Doxo. The combination of SLQD-Doxo was appropriate for drug delivery at high temperatures and acidic pH of tumor cells compared to healthy cells.

Extraction and Biological Activity of Lignanoids from Magnolia officinalis Rehder & E.H.Wilson Residual Waste Biomass Using Deep Eutectic Solvents.

Lignanoids are an active ingredient exerting powerful antioxidant and anti-inflammatory effects in the treatment of many diseases. In order to improve the efficiency of the resource utilization of traditional Chinese medicine waste, Magnolia officinalis Rehder & E.H.Wilson residue (MOR) waste biomass was used as raw material in this study, and a series of deep eutectic solvents (ChUre, ChAce, ChPro, ChCit, ChOxa, ChMal, ChLac, ChLev, ChGly and ChEG) were selected to evaluate the extraction efficiency of lignanoids from MORs. The results showed that the best conditions for lignanoid extraction were a liquid-solid ratio of 40.50 mL/g, an HBD-HBA ratio of 2.06, a water percentage of 29.3%, an extract temperature of 337.65 K, and a time of 107 min. Under these conditions, the maximum lignanoid amount was 39.18 mg/g. In addition, the kinetics of the extraction process were investigated by mathematic modeling. In our antioxidant activity study, high antioxidant activity of the lignanoid extract was shown in scavenging four different types of free radicals (DPPH, ·OH, ABTS, and superoxide anions). At a concentration of 3 mg/mL, the total antioxidant capacity of the lignanoid extract was 1.795 U/mL, which was equal to 0.12 mg/mL of Vc solution. Furthermore, the antibacterial activity study found that the lignanoid extract exhibited good antibacterial effects against six tested pathogens. Among them, Staphylococcus aureus exerted the strongest antibacterial activity. Eventually, the correlation of the lignanoid extract with the biological activity and physicochemical properties of DESs is described using a heatmap, along with the evaluation of the in vitro hypoglycemic, in vitro hypolipidemic, immunomodulatory, and anti-inflammatory activity of the lignanoid extract. These findings can provide a theoretical foundation for the extraction of high-value components from waste biomass by deep eutectic solvents, as well as highlighting its specific significance in natural product development and utilization.

Highly Cytocompatible Polylactic Acid Based Electrospun Microfibers Loaded with Silver Nanoparticles Generated onto Chestnut Shell Lignin for Targeted Antibacterial Activity and Antioxidant Action.

Electrospun (e-spun) fibers are generally regarded as powerful tools for cell growth in tissue regeneration applications, and the possibility of imparting functional properties to these materials represents an increasingly pursued goal. We report herein the preparation of hybrid materials in which an e-spun d,l-polylactic acid matrix, to which chitosan or crystalline nanocellulose was added to improve hydrophilicity, was loaded with different amounts of silver(0) nanoparticles (AgNP) generated onto chestnut shell lignin (CSL) (AgNP@CSL). A solvent-free mechanochemical method was used for efficient (85% of the theoretical value by XRD analysis) Ag(0) production from the reduction of AgNO3 by lignin. For comparison, e-spun fibers containing CSL alone were also prepared. SEM and TEM analyses confirmed the presence of AgNP@CSL (average size 30 nm) on the fibers. Different chemical assays indicated that the AgNP@CSL containing fibers exhibited marked antioxidant properties (EC50 1.6 ± 0.1 mg/mL, DPPH assay), although they were halved with respect to those of the CSL containing fibers, as expected because of the efficient silver ion reduction. All the fibers showed high cytocompatibility toward human mesenchymal stem cells (hMSCs) representative of the self-healing process, and their antibacterial properties were tested against the pathogens Escherichia coli (E. coli), Staphylococcus epidermidis, and Pseudomonas aeruginosa. Finally, competitive surface colonization as simulated by cocultures of hMSC and E. coli showed that AgNP@CSL loaded fibers offered the cells a targeted protection from infection, thus well balancing cytocompatibility and antibacterial properties.

Lignin-cellulose complexes derived from agricultural wastes for combined antibacterial and tissue engineering scaffolds for cutaneous leishmaniasis wounds.

Bacterial infections in wounds significantly impair the healing process. The use of natural antibacterial products over synthetic antibiotics has emerged as a new trend to address antimicrobial resistance. An ideal tissue engineering scaffold to treat infected wounds should possess antibacterial properties, while simultaneously promoting tissue regrowth. Synthesis of hydrogel scaffolds with antibacterial properties using hemp shive (HT1/HT2) lignin, sugarcane bagasse (SCB) lignin and cellulose was carried out. All lignin samples had low molecular weights and were constituted of G-type ß-5 dimers, linked by ß-O-4 bonds, as determined by MALDI-TOF-MS. Hemp lignin was more cytotoxic to mouse fibroblasts (L929) compared to SCB lignin. All lignin samples demonstrated antibacterial properties against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus faecalis, with greater efficiency against Gram-negative strains. 3D hydrogels were engineered by crosslinking SCB lignin with SCB cellulose in varying weight ratios in the presence of epichlorohydrin. The stiffness of the hydrogels could be tailored by varying the lignin concentration. All hydrogels were biocompatible; however, better fibroblast adhesion was observed on the blended hydrogels compared to the 100% cellulose hydrogel, with the cellulose : lignin 70 : 30 hydrogel showing the highest L929 proliferation and best antibacterial properties with a 24-hour bacterial growth reduction ranging from 30.8 to 57.3%.

Supported of gold nanoparticles on carboxymethyl lignin modified magnetic nanoparticles as an efficient catalyst for reduction of nitroarenes and treatment of human melanoma.

This article represents the synthesis and characterizations of Au NPs immobilized and carboxymethyl lignin (CML) modified Fe3O4 nanoparticles (Fe3O4@CML/Au NPs) following a bio-inspired protocol without the participation of any toxic and harmful reductant or stabilizers. Following various physicochemical methodologies, such as FT-IR, FE-SEM, TEM, EDX, XRD, VSM, and ICP-OES, the textural characteristics and different structural aspects were evaluated. The Fe3O4@CML/Au NPs nanocomposite was subsequently explored towards the catalytic reduction of diverse aromatic nitro functions using green conditions. An excellent yield were achieved within very short reaction time. Nine recycling runs of the nanocatalyst were completed without a discernible loss of catalytic activity, thanks to its easy magnetic recovery. The DPPH assay was carried out to examine the antioxidant effectiveness. The Fe3O4@CML/Au NPs nanocomposite inhibited half of the DPPH in a 250 µg/mL solution. To measure the anti-human melanoma efficacy of Fe3O4@CML/Au NPs nanocomposite, MTT assay was applied on HT144, MUM2C, IPC-298 and SKMEL24 cell lines. Fe3O4@CML/Au NPs nanocomposite had high anti-human melanoma efficacy on above tumor cells. The best finding of anti-human melanoma properties of Fe3O4@CML/Au NPs nanocomposite was seen in the case of the SKMEL24 cell line. The IC50 of Fe3O4@CML/Au NPs nanocomposite was 137, 145, 185, and 125 µg/mL against HT144, MUM2C, IPC-298 and SKMEL24 cells, respectively. This research exhibited remarkable anti-human melanoma and antioxidant efficacies of Fe3O4@CML/Au NPs nanocomposite in the in vitro condition.

Enhanced antifungal properties of poly(butylene succinate) film with lignin nanoparticles and trans-cinnamaldehyde for mango packaging.

Sustainable poly(butylene succinate) (PBS) films incorporating lignin nanoparticles (LN) and trans-cinnamaldehyde (CN) have been developed to preserve mango freshness and provide food safety. PBS/LN, PBS/CN, and PBS/LN/CN composite films were produced by blown film melt extrusion. This study investigated the effect of CN-LN on the CN remaining content, thermal, mechanical, and barrier properties, diffusion coefficient, and antifungal activity of PBS films both in vitro and in vivo. Results showed that LN in the PBS/LN/CN composite film contained more CN than in the PBS/CN film. The compatibility of CN-LN with PBS produced homogeneous surfaces with enhanced barrier properties. PBS/LN/CN composite films demonstrated superior antifungal efficacy, inhibiting the growth of Colletotrichum gloeosporioides and preserving mango quality during storage. Results suggested that incorporating LN into PBS composite films prolonged the sustained release of antifungal agents, thereby inhibiting microbial growth and extending the shelf life of mangoes. Development of PBS/LN/CN composite films is a beneficial step toward reducing food waste and enhancing food safety.

High extraction and excellent anti-UV and anti-oxidant proprieties of lignin from Reseda Luteola L. waste by organosolv process.

Lignin is an abundant natural biopolymer found in plant cell walls. Lignin can come from tinctorial plants, whose residual biomass after dye extraction was typically discarded as waste. The main objective of this study was to extract lignin from the residual biomass of Reseda luteola L. using an organosolv process and to optimize the extraction conditions. The extracted lignin was characterized, and its potential applications as an antimicrobial, anti-oxidant, and anti-UV agent were investigated. Response surface methodology based on a Box-Behnken design was employed to optimize the lignin extraction conditions (organic acid concentration, material-to-liquid ratio, extraction time). The extracted lignin was comprehensively characterized using NMR, FTIR, XRD, SEM-EDX, TGA, DSC, and UV-Vis techniques. The optimal extraction conditions yielded a remarkably high lignin recovery of 62.41 % from the plant waste, which was rarely achieved for non-wood plants in previous works. The extracted lignin exhibited excellent thermal stability and radical scavenging anti-oxidant activity but no significant antimicrobial effects. Treating wool fabrics with lignin nanoparticles substantially enhanced UV protection from the "good" to "excellent" category based on the UPF rating. This sustainable valorization approach converted abundant tinctorial plant waste into high-purity lignin with promising anti-oxidant and UV-blocking properties suitable for various applications.

Enhancing the anti-biofouling property of solar evaporator through the synergistic antibacterial effect of lignin and nano silver.

Solar desalination is an effective solution to address the global water scarcity issue. However, biofouling poses a significant challenge for solar evaporators due to the presence of bacteria in seawater. In this study, an anti-biofouling evaporator was constructed using the synergistic antibacterial effect of lignin and silver nanoparticles (AgNPs). The AgNPs were easily synthesized using lignin as reductant under mild reaction conditions. Subsequently, the Lignin-AgNPs solution was integrated into polyacrylamide hydrogel (PAAm) without any purification steps, resulting in the formation of Lignin/AgNPs-PAAm (LAg-PAAm). Under the combined action of AgNPs and the hydroquinone groups present in oxidized lignin, LAg-PAAm achieved over 99 % disinfection efficiency within 1 h, effectively preventing biofilm formation in pore channels of solar evaporators. The anti-biofouling solar evaporator demonstrated an evaporation rate of 1.85 kg m-2 h-1 under 1 sun irradiation, and maintained stable performance for >30 days due to its high efficient bactericidal effect. Furthermore, it also exhibited exceptional salt-rejection capability attributed to its superior hydrophilicity.

Side-stream lignins: Potential antioxidant and antimicrobial agents in milk.

In recent years, lignin has drawn increasing attention due to its intrinsic antibacterial and antioxidant activities, biodegradability, and biocompatibility. Yet, like several other biogenic structures, its compositional heterogeneity represents a challenge to overcome. In addition, there are few studies regarding food applications of lignin. Herein, we evaluate the antimicrobial and antioxidant effects of lignin from two different sources. These lignins were characterized by attenuated total reflectance Fourier-transform infrared (ATR-FTIR) and hydrogen nuclear magnetic resonance (1H NMR) spectroscopies. Their antibacterial and antioxidant capacities (DPPH and Folin-Ciocalteu methods) were also investigated. Susceptibility tests were performed with the minimal inhibitory (MIC) and bactericidal (MBC) concentrations using the micro-broth dilution technique. Kraft lignin presented higher radical-scavenging and antibacterial activities than alkali lignin, indicating the dependence of antioxidant and antibacterial activities on the precursor biomass. Scanning electron microscopy shows morphologic changes in the bacteria after exposure to lignin, while confocal microscopy suggests that kraft lignin has affinity towards bacterial surfaces and the ability to cause cell membrane destabilization. Lignin inhibited the growth of Staphylococcus aureus and Salmonella Enteritidis in skimmed milk, herein taken as food model. Our results suggest that lignins are promising candidates for green additives to improve quality and safety within the food chain.

Antimicrobial Nonisocyanate Polyurethane Foam Derived from Lignin for Wound Healing.

Medical dressings, as a cover for wounds, can replace damaged skin in the wound healing process to play a temporary barrier role, avoid or control wound infection, and provide a favorable environment for wound healing. Therefore, there is an urgent need for medical antimicrobial dressings for the treatment of chronic wounds. Although traditional polyurethane foam has been widely used in medical dressings, conventional polyurethane foams are primarily prepared using nonbiocompatible isocyanate-based compounds, which are potentially hazardous for both operators and applications in the medical field. Here, we propose nonisocyanate polyurethane foams naturally derived from lignin by enzymatic lignin alkylation, cyclic carbonation modification, and polymerization with diamine and the addition of a blowing agent. Silver nanoparticle solution was added during foaming to confer antimicrobial properties. This lignin-based nonisocyanate polyurethane/silver composite foam (named NIPU foam-silver) using a green synthesis method has good mechanical properties, which can be used to manufacture polyurethane/silver foams, and thermal and antimicrobial properties. Notably, NIPU foam-Ag showed more than 95% bactericidal efficacy against both Escherichia coli and Staphylococcus aureus within 4 h. Evaluation of in vitro wounds in mice showed that this antimicrobial composite foam rapidly promotes wound healing and repairs damaged tissue. This suggests that this biobased biodegradable antimicrobial foam has significant scope for clinical applications in wound management.

Ultrasonic-assisted synthesis of lignin-based ultrasmall silver nanoparticles for photothermal-mediated sterilization.

Lignin-based silver nanoparticles have been considered a promising antimicrobial material. However, it remains challenging to prepare ultra-small size silver nanoparticles sustainably with superior antibacterial performance. In this work, we modified ethanol-extracted lignin (EL) with carboxymethyl groups and further synthesized ultra-small particle size (3.8 ± 0.1 nm) nanosilver incorporated carboxymethyl lignin complexes (AgNPs@CEL) using ultrasonic technology. Due to the outstanding antibacterial properties of the ultra-small size nanosilver, AgNPs@CEL could cause 5.3 and 5.4 log10 CFU/mL reduction against E. coli and S. aureus in 5 min. Meanwhile, AgNPs@CEL exhibited remarkable photothermal antibacterial performance, which caused 6.2 and 6.1 log10 CFU/mL reduction of E. coli and S. aureus, with NIR irradiation for 5 min. Furthermore, the composite films prepared by doping only 0.5 wt% AgNPs@CEL into ethyl cellose could achieve a bactericidal rate more than 99.99 %. This study provides a new insight into design of controlled particle size lignin-based antibacterial nanosilver materials in a sustainable manner and holds promise for applications in antibacterial fields.

Exploring the potential of lignin nanoparticles in enhancing the mechanical, thermal, and bioactive properties of poly (butylene adipate-co-terephthalate).

The preparation and characterization of lignin nanoparticles (LNPs) were described. LNPs were produced via the precipitation technique. Nanocomposites of LNPs with poly (butylene adipate-co-terephthalate) (PBAT) were prepared by melt mixing with various concentrations up to 6 wt% of LNPs. The assessment of the effects of LNP addition on the mechanical, thermal, morphological, cytotoxicity, antioxidant, antibacterial, and antiviral properties of nanocomposites was carefully performed. The addition of LNPs to PBAT enhances the thermal stability of the nanocomposites. The antioxidant effect of LNPs on PBAT increased with increasing filler content. LNPs showed higher efficiency as antioxidant agents than lignin particles (LP). The tensile modulus increased by 20 % for the nanocomposites with 6 % LNPs in comparison with neat PBAT. The crystallization peak temperature of PBAT was 80 °C, which increased to 104.6 °C with the addition of 6 wt% of LNPs, suggesting their strong nucleation activity. Antibacterial tests demonstrated the bacteriostatic activities of LNP, LP, and nanocomposites. Both LP and LNP showed considerable antiviral activity against herpes simplex virus type 1 and human coronavirus 229e. The antiviral activity of LNP was concentration-dependent. The findings suggest that LNP is a promising bio-additive for PBAT and can enhance its properties for various applications, including food packaging.

Encapsulated lignin-based slow-release manganese fertilizer with reduced cadmium accumulation in rice (Oryza sativa L.).

As an essential trace element for plant growth and development, manganese plays a crucial role in the uptake of the heavy metal cadmium by rice (Oryza sativa L.). In this study, we developed a novel slow-release manganese fertilizer named Mn@LNS-EL. Initially, lignin nanoparticles were derived from sodium lignosulfonate, and a one-step emulsification strategy was employed to prepare a water-in-oil-in-water (W/O/W) Pickering double emulsions. These double emulsions served as the template for interfacial polymerization of lignin nanoparticles and epichlorohydrin, resulting in the formation of microcapsule wall materials. Subsequently, manganese fertilizer (MnSO4) was successfully encapsulated within the microcapsules. Hydroponic experiments were conducted to investigate the effects of Mn@LNS-EL on rice growth and the cadmium and manganese contents in the roots and shoots of rice under cadmium stress conditions. The results revealed that the treatment with Mn@LNS-EL markedly alleviated the inhibitory effects of cadmium on rice growth, leading to notably lower cadmium levels in the rice roots and shoots compared to the specimens treated without manganese fertilizer. Specifically, there was a reduction of 37.9 % in the root cadmium content and a 17.1 % decrease in the shoot cadmium content. In conclusion, this study presents an innovative approach for the high-value utilization of lignin through effective encapsulation and slow-release mechanisms of trace-element fertilizers while offering a promising strategy for efficiently remediating cadmium pollution in rice.

Green potassium fertilizer from enzymatic hydrolysis lignin: Effects of lignin fractionation on wheat seed germination and seedling growth.

Sustainably sourced lignin presents great potential as a green feedstock for fertilizer production but commercial fulfillment is still challenging owing to the mediocre fertilizer activity of lignin. To address this issue, an effective strategy to enhance the activity of lignin-based potassium fertilizer (LPF) is proposed through lignin fractionation. Three lignin fractions subdivided from enzymatic hydrolysis lignin (EHL) were adopted as the feedstock for LPF preparation, and the effect of lignin fractionation on wheat seed germination and seedling growth was investigated. Compared with the potassium fertilizer from unfractionated lignin, LPF-F1 showed significantly improved effects on promoting seed germination and seedling growth, which can be attributed to the high potassium content resulted from its abundant phenolic hydroxyl and carboxyl contents. Under the optimal treatment concentration (100 mg/L), LPF-F1 showed comparable promotion effect to commercial fulvic acid potassium on wheat seedling growth, suggesting the potential of LPF-F1 as commercial potassium fertilizer. Overall, this work reveals that lignin heterogeneity presents critical effects on the wheat seed germination and seedling growth of LPF, and the fertilizer activity of LPF can be substantially improved using fractionated lignin with low molecular weight as the raw material.

Evaluation of dietary lignin on broiler performance, nutrient digestibility, cholesterol and triglycerides concentrations, gut morphometry, and lipid oxidation.

Two trials were performed in order to evaluate the effects of dietary Kraft lignin inclusion on broiler performance, ileal nutrient digestibility, blood lipid profile, intestinal morphometry, and lipid oxidation of meat. Trial 1 was conducted in order to evaluate performance and ileal digestibility for the period of 1 to 21 d of age, randomly distributing 490 day-old broiler chicks across 5 dietary treatments with 14 replicates containing 7 birds each in metabolic cages, while trial 2 was executed in order to evaluate performance, blood parameters, intestinal morphometry, carcass yield and abdominal fat, and lipid oxidation for the period of 1 to 42 d of age, randomly distributing 900 day-old broiler chicks across 5 dietary treatments with 15 replicates of 12 birds each in floor pens, being each bird in trial 2 challenged with coccidiosis vaccine at 10 d of age. The treatments used in both trials were: positive control (PC): basal diet + antimicrobial; negative control (NC): Basal diet; NC1: NC + 1% lignin; NC2: NC + 2% lignin; NC3: NC + 3% lignin. For trial 1, it was observed that birds fed diets containing 1% lignin had a significant positive effect for BW, feed intake (FI), average daily weight gain (BWG) and feed conversion rate (FCR), similar to the PC, but also showing better EE, CP and AAs ileal digestibility percentages when compared to other treatments. For trial 2, it was observed that during the period of 21 to 35 d, the inclusion of lignin in the diet provided better results in animal performance, similar to the PC group, but at 42 d, animals fed with dietary lignin showed results lower than animals fed the PC diet (P < 0.05). Animals fed with increasing lignin concentrations showed decreasing levels of HDL (P < 0.05). As of intestinal morphometry, animals fed with 1% and 3% lignin showed longer intestinal length (P < 0.05). At 14 d of age, it was observed that animals fed with lignin showed oxidation levels similar to the control treatments. The inclusion of up to 1% lignin in the diet provides beneficial effects on productive performance and nutrient digestibility, while the inclusion of 2% lignin provided lower cholesterol levels, lower villus/crypt ratio, and better internal organ development, therefore, it can be considered an alternative to performance-enhancing antimicrobials in broiler chicken diets.

Hydrogels based on lignin extracted from cashew apple bagasse and its application in antimicrobial wound dressings.

Hydrogels are versatile materials with a three-dimensional network structure that can retain water and release bioactive compounds. They have found applications in various fields, including agriculture, biomaterial synthesis, and pharmaceuticals. Incorporating natural antimicrobial compounds into hydrogels is a promising approach to developing non-toxic biomedical materials, particularly for wound healing dressings. It was evaluated the extraction and use of cashew apple bagasse lignin (CAB-Lig) due to its healing, anti-inflammatory, and antimicrobial properties for producing a hydrogel-based bandage. The extraction process involved acid and alkali treatments followed by precipitation. The antimicrobial potential of CAB-Lig was evaluated at different concentrations for formulating hydrogels. Hydrogels containing 0.1 % and 3 % lignin showed high swelling and liquid retention abilities. The 3 % lignin hydrogel exhibited effectiveness against Escherichia coli and Staphylococcus aureus. Incorporating CAB-Lig into the hydrogel structure improved its mechanical properties, making it more suitable for application as a bandage. Moreover, the extracted lignin showed low toxicity, indicating its safe use. A bandage was formulated by combining the CAB-Lig-based hydrogel with polyester, which possessed antimicrobial properties and demonstrated biocompatibility (L929 and HaCat cells). The results confirmed the potential of CAB-Lig for synthesizing hydrogels and dressings with antimicrobial properties, offering a sustainable solution for utilizing lignocellulosic biomass.

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.

Bifunctional lignocellulose nanofiber hydrogel possessing intriguing pH-responsiveness and self-healing capability towards wound healing applications.

Lignocellulose nanofibers (LCNF) obtained from agricultural waste are potential candidates for enhancing composite materials because of their excellent mechanical properties, abundant groups and high biocompatibility. However, the application of LCNF has received limited attention to date from researchers in the healthcare field. Herein, based on the bifunctional group (carboxyl and aldehyde groups) modified LCNF (DCLCNF) and chitosan (CS), we developed a multifunctional bio-based hydrogel (CS-DCLCNF). The addition of lignin-containing DCLCNF strengthened the internal crosslinking and the intermolecular interaction of hydrogels, and the presence of lignin and carboxyl groups increased the mechanical strength of the hydrogel and the adsorption of aromatic drugs. Results revealed that the hydrogels exhibited self-healing, injectable, and high swelling rates. The hydrogels had favorable mechanical strength (G'max of ~16.60 kPa), and the maximum compressive stress was 24 kPa. Moreover, the entire tetracycline hydrochloride (TH) release process was slow and pH-responsive, because of the rich noncovalent and π-π interactions between DCLCNF and TH. The hydrogels also exhibited excellent biocompatibility and antibacterial properties. Notably, the wound healing experiment showed that the hydrogels were beneficial in accelerating wounds healing, which could heal completely in 13 days. Therefore, CS-DCLCNF hydrogels may have promising applications in drug delivery for wound healing.

Antitumor Effects of Carrier-Free Functionalized Lignin Materials on Human Hepatocellular Carcinoma (HepG2) Cells.

Lignin, as an abundant aromatic biopolymer in plants, has great potential for medical applications due to its active sites, antioxidant activity, low biotoxicity, and good biocompatibility. In this work, a simple and ecofriendly approach for lignin fractionation and modification was developed to improve the antitumor activity of lignin. The lignin fraction KL-3 obtained by the lignin gradient acid precipitation at pH = 9-13 showed good cytotoxicity. Furthermore, the cell-feeding lignin after additional structural modifications such as demethylation (DKL-3), sulfonation (SL-3), and demethylsulfonation (DSKL-3) could exhibit higher glutathione responsiveness in the tumor microenvironment, resulting in reactive oxygen species accumulation and mitochondrial damage and eventually leading to apoptosis in HepG2 cells with minimal damage to normal cells. The IC50 values for KL-3, SL-3, and DSKL-3 were 0.71, 0.57, and 0.41 mg/mL, respectively, which were superior to those of other biomass extractives or unmodified lignin. Importantly, in vivo experiments conducted in nude mouse models demonstrated good biosafety and effective tumor destruction. This work provides a promising example of constructing carrier-free functionalized lignin antitumor materials with different structures for inhibiting the growth of human hepatocellular carcinoma (HepG2) cells, which is expected to improve cancer therapy outcomes.