Total Hydroxyl Research Articles

Effects of ethanol pretreatment on dissolution and structural changes of lignin from steam-exploded wheat straw

Pretreatment of steam-exploded wheat straw by ethanol has been used to dissolve lignin. Different pretreatment conditions were explored by varying reaction temperature, time, and the ratio of solid to liquid to determine that the rate of dissolution was approximately 51.6%. The examination of structural changes in LP (lignin from ethanol pretreatment pulp) showed that the conjugated carbonyl/carboxyl of lignin was partly destroyed during ethanol pretreatment and alkali extraction process. The content of total hydroxyl groups was increased with increasing ethanol pretreatment. Higher intensities of the aromatic ring in LP and LL (lignin from black liquor) fractions compared to that of weak pretreatment conditions indicated that some extent of lignin condensation occurred during the ethanol pretreatment. The ratios of S/G in LP were higher than in LL and removal of the methoxyl groups happened during the ethanol pretreatment process, and this led to changes in proportions of lignin structural units.

Unraveling the association of fecal microbiota and oxidative stress with stillbirth rate of sows

Previous studies have shown that the composition and function of gut microbiota possibly contribute to the oxidative stress and host metabolism of sows. However, a functional link between gut bacteria with oxidative stress and stillbirth rate of sows remain unclear. To address this issue, the reproductive performance, oxidative stress and gut microbiota of sows with high (H) and low (L) stillbirth rate were analyzed. Results showed that, compared with the H group, the L group had a shorter farrowing duration as well as higher concentration of serum total antioxidant capacity and hydroxyl radical scavenging capacity. For the gut microbiota composition of the tested sows, 6 genera differed between the two groups, 7 genera were correlative with stillbirth rate, and 2 genera were correlated with farrowing duration. The relative abundance of Lachnospiraceae_UCG-001, Marvinbryantia and Ruminococcaceae_UCG-004 were negatively correlated with antioxidant capacity, but positively correlated with the stillbirth rate of sows. Furthermore, the microbiota functions in the polyketide sugar unit biosynthesis and nitrotoluene degradation were found to be different between the two groups through the phylotypic investigation of communities by reconstruction of unobserved states. Collectively, gut microbiota and their functions vary between sows with high or low stillbirth rate, while stillbirth rate and farrowing duration are significantly correlated with the gut microbiota composition and oxidative stress status of sows.

Diminishing bioavailability and toxicity of P25 TiO2 NPs during continuous exposure to marine algae Chlorella sp.

Titanium dioxide nanoparticles (TiO2 NPs) find applications in our day-to-day life because of unique physicochemical properties. Their release into the aquatic environment poses a possible risk to the organisms. However, the continuing exposure of NPs might reduce their bioavailability to marine organisms owing to aggregation and sedimentation in the aqueous systems thus significantly reducing their toxic impact. In this regard, the present study investigates the effect of continuous exposure of TiO2 NPs to marine microalgae Chlorella sp. under UV-A irradiation through “tanks in series” mode of experiments. In a three-cycle experiment, concentration of TiO2 NPs in the first cycle was fixed at 62.6 μM, and the interacted nanoparticles was subsequently exposed to fresh batches of algae in the next two cycles. After the interaction, the NPs underwent severe aggregation (mean hydrodynamic diameter 3000 ± 18.2 nm after cycle I) leading to gravitational settling in the medium and thus decreased bioavailability. The aggregation can be attributed to interactions between the particles themselves (homo-aggregation) further aggravated by the presence of the algal cells (hetero-aggregation). Cellular viability after cycle I was found to be only 24.2 ± 2.5%, and it was enhanced to 96.5 ± 2.8% after the cycle III in the course of continuous exposure. The results were validated with estimation of oxidative stress markers such as intracellular ROS (total ROS, superoxide and hydroxyl radicals) and LPO after each cycle of exposure. The continuing decrease in the EPS across the cycles further confirmed the diminishing toxicity of the NPs.

Persea americana Leaf Ethyl Acetate Extract Phytochemical, In-vitro Antioxidant and In-vivo Potentials to Mitigate Oxidative Stress in Alloxan-induced Hyperglycaemic Rats

The purpose of this study was to investigate the in-vivo and in-vitro potentials of ethyl acetate extract of P. americana leaf in alloxan-induced diabetic rats. Quantitative phytochemicals analyzed includes; flavonoids, saponins, tannins, alkaloids and phenolics. Measurement of antioxidant activity using 1,1-Diphenyl-2-picrylhydrazyl, total antioxidant capacity, hydroxyl radical, hydrogen peroxide, superoxide radical and ferric reducing activity of the extract was carried out. Hyperglycemia was induced by intraperitoneal injection of alloxan monohydrate to albino rats. In-vivo anti-oxidant potentials of the extract were evaluated by measuring liver homogenate activity of superoxide dismutase, catalase, glutathione reductase, glutathione peroxidase and malondyaldehyde in alloxan-induced diabetic rats administered with the extract. A total of 30 Albino rats were used for this experiment and they were divided into six groups of 5 rats each. Group A; normal control, Group B; diabetic control, Groups C-E; experimental groups administered with different doses (100, 200 and 400 mg/kg body weight respectively); of the extract and Group F; glucophage (84 mg/kg body weight, standard drug) for 4 weeks. This study was conducted in the Department of Biochemistry, Bayero University, Kano, in August, 2018. Data was analyzed using one-way ANOVA with P=.05 value considered as significant. Results of the quantitative phytochemical investigation shows that the extract is rich in phenolics (184.1±0.6), flavonoids (115.8±2.1), alkaloids (41.5±1.8), with least concentration of tannis (21.2±0.8) and saponins (15.2±2.3). The extract exhibited high radical scavenging activity against synthetic free radicals (DPPH), reactive oxygen species (peroxide, superoxide and hydroxyl acid) and high ability to reduce Fe3+ to Fe2+ (FRAP). The activities of antioxidant enzymes of the treated rats were increased significantly (P=.05) while the level malondyaldehyde was significantly decreased (P=.05) in the treated groups. Ethyl acetate leaf extract of Persea americana contains phytochemical substances which improved antioxidant status and can be use as herbal therapy for the management of oxidative stress induced by diabetes mellitus and associated complications.

In Vitro Evaluation of Free Radical Scavenging, Fe2+ and SNP-Induced Lipid Peroxidation (Rat Brain) Activities of Methanolic Extracts from Three (3) Northern Nigerian Plants Leaf

Over the years research findings have shown that free radicals are the basis for many diseases. This study sought to investigate the free radical scavenging and inhibition of lipid peroxidation activities of some three Northern Nigerian plant leaf; Boswellia dalzielii Hutch. (Burseraceae) (BDL), Detarium microcarpum Guill. and Perr. (DML), and Daniellia oliveiri (Rolfe) Hutch. & Dalz (DOL). The study investigated both qualitative and quantitative phytochemical screening, free radical scavenging activities of 1, 1-diphenyl–2-picrylhydrazyl DPPH, total antioxidant capacity ABTS, hydroxyl, reducing property and inhibition of lipid peroxidation. All the seven phytochemicals screened were all present in both BDL and DML plant extracts but saponins and glycosides were absent in DOL plant leaf. The result revealed that BDL methanolic extract had the highest total flavonoid and phenolic content while BDL methanolic extract had the highest alkaloid content. DOL methanolic extract had the least content in all the 3 phytochemicals quantified. BDL methanolic extract had the highest free radical scavenging activity in 1, 1-diphenyl–2-picrylhydrazyl (DPPH), Hydroxyl and reducing power assays. While DML methanolic extract, had the highest free radical scavenging ability in 2, 2-azino-bis(3-ethylbenzazoline-6-sulphonic acid (TEAC) assays. The IC 50 of BDL extract (12.37 mg/mL) was not significantly different (p > 0.05) from DML extract (10.39 mg/mL) in the Fe 2+ -induced lipid peroxidation assay. While, the IC 50 of DML extract (14.83 mg/mL) was significantly higher (p < 0.05) than the BDL extract (19.92 mg/mL) in the SNP-induced lipid peroxidation. The DOL extract had the least scavenging and peroxidative inhibitory activity in all the assays carried out. We therefore concluded that the synergistic free radical scavenging activities and inhibition of lipid peroxidation of the three plants studied (especially, BDL and DML), provides a biochemical rationale for their usage as a medicinal plant.

Characterization and evaluation of antioxidation of lignin from bamboo powder using a formic acid-catalyzed ethanol organosolv process

The antioxidant activity of lignin for producing biochemicals has attracted attention. In this paper, a separation method for lignin is proposed, with high-yield and high-antioxidant activity by using a formic acid-catalyzed subcritical ethanol process. The formic acid-catalyzed ethanol lignin (EOL/FA) and ethanol organosolv lignin (EOL) were first prepared using a high-pressure autoclave at different formic acid dosages. Then, the antioxidant activity and the structural and thermal properties of EOL/FA, EOL, alkali lignin, and sodium lignosulfonate were analyzed using antioxidant analysis, Fourier transform infrared (FTIR) spectroscopy analysis, and thermogravimetric analysis (TGA). The phenolic hydroxyl content of the four lignins was also determined by the Folin–Ciocalteau colorimetric method. Results showed EOL/FA had a higher radical scavenging ability and higher total phenolic hydroxyl content than industrial lignin. It indicated that the formic acid-catalyzed subcritical ethanol process was effective for enhancing the antioxidant activity of lignin.

Metabolic changes induced by manganese in chamomile

Manganese (Mn) uptake and toxicity in chamomile (Matricaria chamomilla) and changes of phenolic metabolites in plants grown in the soil (1000 μM Mn2+) or hydroponic culture (100 or 1000 μM Mn2+) were studied. Under soil cultivation, Mn excess reduced growth and induced symptoms of oxidative stress (including total ROS, hydroxyl radical and lipid peroxidation as detected by fluorescence microscopy), concomitantly with depletion of non-protein thiols and ascorbic acid. Total soluble phenols and individual phenolic acids were rather depleted (p-coumaric, chlorogenic, and protocatechuic acids) or unaltered (vanillic and caffeic acids). Shoot Mn content reached 2806 μg/g DW with BAF 51.0 in the soil culture. In hydroponics, tetraploid plants contained less Mn in both shoots and roots than diploid ones with bioaccumulation factor and translocation factor (diploid/tetraploid) 57.1/37.9 and 0.39/0.32 in 1000 μM Mn treatment. Plants cultured in hydroponics revealed stimulation of some phenolic acids, mainly chlorogenic acid in the shoots and p-hydroxybenzoic and vanillic acids in the roots (more extensively in tetraploid ones which contained less Mn). Data indicate that excessive Mn accumulation has negative impact not only on the growth but also on phenolic metabolites in young plants mainly. Detailed comparison of the observed metabolic changes with limited literature focused on Mn physiology is provided as well.

Zirconia-supported 12-tungstophosphoric acid: Characterization and catalytic behavior in degradation of alkali lignin

Degradation of alkali lignin (AL) is important for practical applications of this valuable natural resource. 12-Tungstophosphoric acid (TPA), supported on materials with a high surface area, has been shown to be an effective catalyst for the degradation of AL. This complex catalyst is, however, relatively unstable and there are a limited number of suitable supporting materials. To overcome these problems, we prepared ZrO2-supported TPA and demonstrated that this is an effective catalyst for the degradation of AL. Catalysts with different TPA loadings (10–40 wt%) were prepared using different calcinations temperatures (200–500 ℃). The catalysts were characterized by X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, field emission scanning electron microscopy (FESEM), and surface area measurements. Catalyst loaded with 20% TPA and prepared at 200 ℃ demonstrated the highest catalytic efficiency when the catalyst-to-lignin ratio was 1:8. Under these conditions, total hydroxyl groups and phenolic hydroxyl groups increased by 203.9% and 148.4%, respectively. The catalyst could be reused at least three times, without significant loss of activity. This method thus represents a green and effective alternative for the degradation of AL into valuable small molecules.

Quantitative comparison of surface properties of enzymatic hydrolysis lignin before and after degradation

The high value utilization of lignin is attracting increased attention because of environmental problems and resource depletion. Although these are numerous reports describing the modification and degradation of enzymatic hydrolysis lignin (EHL), quantitative characterization is lacking. In this work, EHL was efficiently degraded using H3PW12O40/ZrO2 (HPW/ZrO2) as catalyst. Following degradation, the total hydroxyl group content and phenolic hydroxyl group content, measured by acid-base titration and ultraviolet spectrophotometry, were increased by 259% and 152%, respectively. Hansen solubility parameters were calculated using the specific retention time of probe solvents, measured by inverse gas chromatography (IGC), quantitatively characterizing changes in surface properties.

Uniform Chemical Functionality of Technical Lignin Using Ethylene Carbonate for Hydroxyethylation and Subsequent Greener Esterification

Full utilization of plant-based feedstocks for sustainable societies must include the valorization of lignin, an abundant aromatic component of the cell wall of plant stems, in processes that follow green chemistry principles. However, one of the major issues limiting lignin utilization is the chemical nonuniformity of the isolated polymer, along with the thermal sensitivity of the free phenolics which hinders processing at elevated temperatures. To address these issues, free phenolics and carboxylic acids of industrial lignins were hydroxyalkylated through the use of ethylene carbonate, which served as both the reagent and the solvent. This facile and safe reaction resulted in near complete conversion of phenolics and carboxylic acids into aliphatic hydroxyls resulting in uniform chemical functionality and enhanced thermal stability. However, the increased reaction temperature decreased the total hydroxyl content and increased the molecular weight of the lignin; the work identified a narrow processing wi...

Characterization of Lignin Extracted from Willow by Deep Eutectic Solvent Treatments.

Purity, morphology, and structural characterization of synthesized deep eutectic solvent (DES)-lignins (D6h, D9h, D12h, D18h, D24h) extracted from willow (Salix matsudana cv. Zhuliu) after treatment with a 1:10 molar ratio of choline chloride and lactic acid at 120 °C for 6, 9, 12, 18, and 24 h were carried out. The purity of DES-lignin was ~95.4%. The proportion of hydrogen (H) in DES-lignin samples increased from 4.22% to 6.90% with lignin extraction time. The DES-lignin samples had low number/weight average molecular weights (1348.1/1806.7 to 920.2/1042.5 g/mol, from D6h to D24h) and low particle sizes (702–400 nm). Atomic force microscopy (AFM) analysis demonstrated that DES-lignin nanoparticles had smooth surfaces and diameters of 200–420 nm. Syringyl (S) units were dominant, and total phenolic hydroxyl content and total hydroxyl content reached their highest values of 2.05 and 3.42 mmol·g−1 in D12h and D6h, respectively. β-Aryl ether (β-O-4) linkages were eliminated during DES treatment.

Upgrading the antioxidant properties of fucoidan and alginate from Cystoseira trinodis by fungal fermentation or enzymatic pretreatment of the seaweed biomass

The seaweed Cystoseira trinodis was fermented by different fungi prior to extraction of fucoidan and alginate to enhance their antioxidative potential. All the investigated fungi were able to produce fucoidanase (1.05–3.41 U/ml) and alginate lyase (7.27–18.59 U/mL). Different fungal species induced a reduction in the molecular weight (MW) of fucoidan and alginate in comparison to the unfermented control. The MW of fucoidan reduced by 41–81.5%, while the MW of alginate was reduced by 28–75%, depending on the fungal species. Significant increases in the fucose and sulphate contents of fucoidan and mannuronic/guluronic acid ratio of alginate were induced by fungal fermentation. Fungal pretreatment enhanced the ferric reducing antioxidant power, total antioxidant capacity and hydroxyl radical scavenging activity of both fucoidan and alginate. Additionally, enzymatic pretreatment of the macroalgal biomass assisted in the recovery of fucoidan and alginate with low molecular weight and enhanced antioxidative potential.

Phytochemical Screening and Biological Activity of Extract Berries of Black Currant (Ribes nigrum L.)

The objective of this study was to identify and quantify phenolic compounds, antioxidant and antimicrobial activity in extract of berries of seven black currant cultivars (‘Ben Lomond’, ‘Ben Sarek’, ‘Titania’, ‘Cacanska Crna’, ‘Tisel’, ‘Tiben’ and ‘Tsema’). High performance liquid chromatography-diode array detector (HPLC-DAD) technique was used to establish the profile of phenolic compounds. Antioxidant properties were evaluated using different methods, including total antioxidant capacity, DPPH and hydroxyl radicals scavenging activities, as well as inhibition of lipid peroxidation. The highest amounts of phenolics (15.0 mg GAE/g), flavonoids (5.25 mg RU/g) and antioxidant capacity (12.4 mg AA/g) were found in the cultivar ‘Cacanska Crna’, whereas the other cultivars exhibited variability in the studied parameters. The fruits of black currant contained high concentrations of flavonols and phenolic acids. The main phenolic compounds were quercetin and caffeic acid. All explored extracts exhibited strong scavenging activity against DPPH radicals, which ranges from 56.19 μg/mL (‘Titania’) to 61.17 μg/mL (‘Tisel’). The antimicrobial activity was tested using broth dilution procedure for determination of the minimum inhibitory concentration (MIC). The MICs were determined for 8 selected strains. All extracts showed strong antimicrobial activity, in the range between 50.65 μg/mL and 166.38 μg/mL. Black currant fruit extract, rich in phenolic compounds and with strong antioxidant activity can be used as natural antioxidant in food and pharmaceutical industries.

De-polymerization of industrial lignins to improve the thermo-oxidative stability of polyolefins

De-polymerized lignins with greatly reduced molecular weight (<1700 g/mol based on GPC-UV) and increased reactivity were prepared from two types of technical lignin, kraft and hydrolysis, using a proprietary de-polymerization technique. The resulting de-polymerized kraft and hydrolysis lignins (DKL and DHL) have increased aromatic hydroxyl content and decreased aliphatic content, and thus decreased total hydroxyl content and decreased polarity compared to the original lignins. Both types of de-polymerized lignin tested showed significant improvement in the thermo-oxidative stability of the polyolefins as measured by oxidation induction time, activation energy, initial degradation temperature and maximum degradation temperature. The de-polymerized lignins had up to five times more antioxidant activity than the crude lignins as a result of their higher phenolic content, improved hydrophobicity, and lower molecular weight. De-polymerized KL (DKL) had the strongest antioxidant effects, followed by de-polymerized HL (DHL), KL and HL: this correlates with their phenolic content. Mechanical tests show that incorporating de-polymerized lignins did not degrade the mechanical properties of the polymers. These properties are to be investigated further.

Utilization of Cuttlefish Liver Waste for Oil Production: Evaluation of Quality Characteristics and Biological Activity

The ash, moisture, protein and carbohydrate content of the extracted oil were estimated as 4, 7, 4 and 1% respectively. The Vitamins A and E was found to be 59.14 and 17.4 mg/100 g. Nine fatty acids were found and the Linoleic acid, DHA and EPA were recorded as higher. The specific gravity, solidification point, refractive index, saponification value, iodine value and acid value were also calculated and found as 1.056, 1.2 °C, 1.465 µ, 50.5, 20.4 mg and 0.075 mg KOH/g. The antioxidant activity that includes total antioxidant activity, DPPH & Hydroxyl radical scavenging assay, reducing power and ferrous ion chelating activity of liver oil was studied by following standard methods and results of all the assays was found increasing with increase in concentration. Further purification of liver oil and studying its antioxidant property in animal model shall form the basis for its use as a potent alternate natural antioxidant and nutrition supplements.

Summertime OH reactivity from a receptor coastal site in the Mediterranean Basin

Abstract. Total hydroxyl radical (OH) reactivity, the total loss frequency of the hydroxyl radical in ambient air, provides the total loading of OH reactants in air. We measured the total OH reactivity for the first time during summertime at a coastal receptor site located in the western Mediterranean Basin. Measurements were performed at a temporary field site located in the northern cape of Corsica (France), during summer 2013 for the project CARBOSOR (CARBOn within continental pollution plumes: SOurces and Reactivity)–ChArMEx (Chemistry and Aerosols Mediterranean Experiment). Here, we compare the measured total OH reactivity with the OH reactivity calculated from the measured reactive gases. The difference between these two parameters is termed missing OH reactivity, i.e., the fraction of OH reactivity not explained by the measured compounds. The total OH reactivity at the site varied between the instrumental LoD (limit of detection = 3 s−1) to a maximum of 17 ± 6 s−1 (35 % uncertainty) and was 5 ± 4 s−1 (1σ SD – standard deviation) on average. It varied with air temperature exhibiting a diurnal profile comparable to the reactivity calculated from the concentration of the biogenic volatile organic compounds measured at the site. For part of the campaign, 56 % of OH reactivity was unexplained by the measured OH reactants (missing reactivity). We suggest that oxidation products of biogenic gas precursors were among the contributors to missing OH reactivity.

Synthesis and Characterization of Bio-oil-Based Self-Curing Epoxy Resin

A novel self-curing epoxy resin was synthesized using bio-oil. Bio-oil was produced by hydrothermal liquefaction of loblolly pine and utilized as a biopolyol in the synthesis of bio-oil-based epoxy resin (BOBER) for the first time. Hydroxyl groups in bio-oil were analyzed by quantitative 31P NMR. It was found that not only does the total hydroxyl number of bio-oil influence the yield and epoxy equivalent weight of BOBER, but also the distribution of hydroxyl groups within bio-oil (aliphatic, phenolic, and acidic OH) played an important role in the determination of the optimum amount of catalyst in the synthesis of BOBER. Differential scanning calorimetry analysis proved the self-curing phenomena of BOBER, and Fourier transform infrared spectroscopy suggested that etherification reaction was the dominate reaction during the self-curing. Glass transition temperature, cross-linking density, and the storage modulus of self-cured BOBER were calculated using a dynamic mechanical analyzer.

Characterization of products from hydrothermal carbonization of pine

This study aims to reveal the structural features and reaction pathways for solid–liquid products from hydrothermal carbonization of Loblolly pine, where the solid products can be used as catalysts, adsorbents and electrode materials while liquid products can be treated yielding fuels and platform chemicals. Results revealed when treated at 240°C, cellulose and hemicellulose were degraded, in part, to 5-hydroxy-methyl furfural and furfural which were further transformed to aromatic structures via ring opening and Diels Alder reactions. Lignin degradation and formation of carbon–carbon bonds, forming aromatic motifs in the presence of furanic compounds connected via aliphatic bridges, ether or condensation reactions. After hydrothermal treatment, condensed aromatic carbon materials with methoxy groups were recovered with high fixed carbon content and HHV. The recovered liquid products are lignin-like value-added chemicals consisting of furfural and polyaromatic structure with alkanes and carboxyl, their total hydroxyl group content decreased when increasing reaction time.

Biochemical and antioxidant properties of peptidic fraction generated from crab (Portunus trituberculatus) shells by enzymatic hydrolysis

SummaryThe biochemical properties and in vitro antioxidant activity of the crab (Portunus trituberculatus) shell hydrolysates (CSHs) generated by pepsin and protamex hydrolysis were evaluated. The amino acids profile of CSHs showed a high percentage of essential amino acids (&gt;36%). The hydrolysates were mainly composed of low molecular weight peptides (&lt;3 kDa). CSHs showed excellent solubility and possessed interfacial properties, which were governed by their concentrations. The antioxidant activities of CSHs were evaluated using various in vitro antioxidant assays, including the total antioxidant activity, DPPH, hydroxyl and ABTS radical scavenging method and reducing power assay. CSHs exhibited a good antioxidant activity compared to that of ascorbic acid. Results from this study suggested that the peptidic fractions of crab shells were good source of natural antioxidants and peptides with interesting functionalities.

Hydrogenolysis and Activation of Soda Lignin Using [BMIM]Cl as a Catalyst and Solvent.

To improve the reactivity of the soda lignin, an acid ionic liquid 1-butyl-3-mthylimidazolium chloride ([BMIM]Cl) was used as the catalyst and solvent to degrade the soda lignin through hydrogenolysis. Structural elucidation of the lignin samples was conducted by using a combination of analytical methods including chemical analysis, ultraviolet spectrophotometry (UV spectrophotometry), Fourier transform infrared spectroscopy (FT-IR spectra), two-dimensional heteronuclear single quantum coherence nuclear magnetic resonance (2D-HSQC NMR) techniques, and gel permeation chromatography (GPC). The antioxidant activities of the lignin samples were evaluated using the diammonium 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS+) radical scavenging and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging methods. The degradation mechanism was proposed based on the characterization results. The optimal reaction condition was as follows: the concentration of [BMIM]Cl in the solution was 10 wt %, the hydrogen initial pressure was 3 MPa, and the solution was heated for 4 h at 90 °C. After the reaction, the total hydroxyl content of the soda lignin increased by 81.3%, while the phenolic hydroxyl content increased by 23.1%. At the same time, the weight-average molar mass of the soda lignin sample decreased from 8220 to 6450 g/mol with an improved antioxidant activity. In addition, approximately 56.7% of the β-O-4 linkages were degraded in the lreaction. The main effect of the acid ionic liquid [BMIM]C1 was related to the cleavage of β-O-4 linkages. This study has shown the potential of using the catalyzed soda lignin as a natural polymer antioxidant.