The development of biomaterials-based adhesives is one of the main research directions for the wood-based material industry. In previous research, tannin and sucrose were used as adhesive to ...manufacture particleboard. However, the reaction conditions need to be optimized. In this study, sulfuric acid was added to the tannin⁻sucrose adhesive as a catalyst to improve the curing process. Thermal analysis, insoluble mass proportion, FT-IR, and solid state
C NMR were used to investigate the effects of sulfuric acid on the curing behavior of tannin and sucrose. Thermal analysis showed weight loss and endotherm temperature reduced from 205 and 215 to 136 and 138 °C, respectively, by adding sulfuric acid. In case of the adhesive with pH = 1.0, the insoluble mass proportion achieved 81% at 160 °C, which was higher than the reference at 220 °C. FT-IR analysis of the uncured adhesives showed that adding sulfuric acid leads to hydrolysis of sucrose; then, glucose and fructose converted to 5-hydroxymehthylfurfural (HMF) and levulinic acid. Dimethylene ether bridges were observed by FT-IR analysis of the cured adhesives. The results of solid state
C NMR spectrum indicated that 5-HMF participated in the curing process and formed methylene bridges with the C8 position of the resorcinol A-rings of tannin, whereas dimethylene ether bridges were detected as a major chemical chain of the polymer. Lab particleboards were produced using 20 wt % resin content at 180 °C and 10 min press time; the tannin⁻sucrose adhesive modified with sulfuric acid to pH = 1.0 exhibited better performance than the unmodified tannin⁻sucrose adhesive; the properties of the boards fulfilled the requirement of Japanese Industrial Standard (JIS) A5908 type 15.
Bacterial cellulose (BC) is an exopolysaccharide with unique properties that has been applied in various fields. However, the dense and intertwined nature of BC fibers limits its use in certain ...applications, including 3D printing scaffolds for bone regeneration. In this work, a controllable BC-based bio-ink for 3D printing was successfully prepared by modifying the neat BC through maleic acid (MA) treatment, aiming to promote bone tissue regeneration. To achieve homogeneous BC dispersions while preserving its crystalline and chemical properties, BC was modified by MA solution (60 %, w/V) with solid-liquid ratio from 1꞉5 to 1꞉50 (w/V) to obtain MA-BC dispersions. The analysis results from microstructure, chemical group, crystallinity, and wettability indicated that the BC/MA solution with ratio of 1꞉30 demonstrated the best pre-treatment performance to obtain MA-BC. Subsequently, by combining MA-BC with gelatin, we successfully formulated MA-BC-GEL gels with favorable rheological properties and compression modulus, which can be used as promising bio-inks for 3D bioprinting applications. In vitro tests demonstrated 1꞉30 MA-BC possessed excellent biocompatibility, a significant ability to express the alkaline phosphatase gene and osteogenic-related genes, and facilitated the formation of mineralized nodules. The utilization of this novel bio-ink in scaffold preparation for bone regeneration highlights the promising application of modified BC in bone tissue engineering field.
Skin is the largest organ of humans. Overexposure to ultraviolet (UV) is the primary environmental factor that causes skin damage. The compound, (-)-loliode, isolated from the brown seaweed
, showed ...strong antioxidant and anti-inflammatory activities in in vitro and in vivo models. To further explore the potential of (-)-loliode in cosmetics, in the present study, we investigated the photoprotective effect of (-)-loliode in vitro in skin cells and in vivo in zebrafish. The results indicated that (-)-loliode significantly reduced intracellular reactive oxygen species (ROS) level, improved cell viability, and suppressed apoptosis of UVB-irradiated human keratinocytes. In addition, (-)-loliode remarkably attenuated oxidative damage, improved collagen synthesis, and inhibited matrix metalloproteinases expression in UVB-irradiated human dermal fibroblasts. Furthermore, the in vivo test demonstrated that (-)-loliode effectively and dose-dependently suppressed UVB-induced zebrafish damage displayed in decreasing the levels of ROS, nitric oxide, lipid peroxidation, and cell death in UVB-irradiated zebrafish. These results indicate that (-)-loliode possesses strong photoprotective activities and suggest (-)-loliode may an ideal ingredient in the pharmaceutical and cosmeceutical industries.
A novel coated urea (MVCU) was prepared, and its application effect was verified by field trials of oilseed rape in three main cultivation areas. Meanwhile, the nutrient release and coating layer ...changes of MVCU in static water at 25 °C and different soils were systematically evaluated. MVCU showed a long nutrient release time under static water (77 days) and soil incubation (140 days) conditions due to the slow degradation of the coating layer in MVCU, and its nitrogen release coincided well with oilseed rape nitrogen demand. The above results were further confirmed by FT-IR spectra and SEM analysis. Compared with conventional urea (U), the field trials of MVCU in the three main cultivation areas showed high nitrogen utilization efficiency and yield advantages in oilseed rape. The field trials results indicated that the MVCU significantly enhanced the aboveground dry matter (28.7%), the seed nitrogen concentration (9.5%) and aboveground nitrogen accumulation (42.5%) of oilseed rape at the mature stage as compared to that of the U. The oilseed rape yield enhanced by 932.8 kg/hm2, the average growth rate was 65.1%, and nitrogen utilization efficiency increased by 21.2%. In short, MVCU has the advantages of excellent slow-release performance and strong applicability, and its yield-increasing effect on oilseed rape could reach or even be better than that of traditional fertilization.
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•A novel coated urea was prepared and its application effect was verified.•Nutrient release and coating layer changes of coated urea were evaluated.•Coated urea showed high nitrogen utilization efficiency and yield advantages.•Coated urea has the advantages of excellent slow-release performance and strong applicability.
Lignin-carbohydrate complexes (LCCs) from different lignocellulosic biomass have shown biological qualities as antioxidant and immunostimulant. By contrast, the application of LCCs as protectant ...against neurotoxicity caused by different compounds is scarce. In this work, two kinds of LCCs with carbohydrate-rich and lignin-rich fractions were obtained from wheat stalk and used to protect against BPA-neurotoxicity in zebrafish. The results showed that BPA at a concentration of 500 µg/L results in neurotoxicity, including significant behavioral inhibition, and prevents the expression of central nervous system proteins in transgenic zebrafish models (Tg (HuC-GFP)). When the zebrafish was treated by LCCs, the reactive oxygen species of zebrafish decreased significantly with the change of antioxidant enzymes and lipid peroxidation, which was due to the LCCs’ ability to suppress the mRNA expression level of key genes related to nerves. This is essential in view of the neurotoxicity of BPA through oxidative stress. In addition, BPA exposure had negative effects on the exercise behavior, the catalase (CAT) and superoxide dismutase (SOD) activity, and the larval development and gene expression of zebrafish larvae, and LCC preparations could recover these negative effects by reducing oxidative stress. In zebrafish treated with BPA, carbohydrate-rich LCCs showed stronger antioxidant activity than lignin-rich LCCs, showing their potential as a neuroprotective agents.
Chlorella pyrenoidosa (C. pyrenoidosa) has been widely used in commercial food and feed production for numerous years. Its high protein content and cost-effectiveness make it an attractive source of ...novel protein. With a focus on sustainable development and the search for green natural products, current research is dedicated to maximizing the utilization of C. pyrenoidosa protein (CPP) and peptide. Various techniques, such as the use of ionic liquids, freeze-thawing, ultrasonication, enzyme digest, microwaving are employed in the extraction of CPP. The extracted CPP has demonstrated antioxidant, anti-inflammatory, and bacteriostatic properties. It can also stimulate immune regulation, prevent cardiovascular disease, protect red blood cells, and even be used in wastewater treatment. Furthermore, CPP has shown some potential in combating obesity. Additionally, CPP is being explored in three-dimensional (3D) printing applications, particularly for the creation of biological scaffolds. It is also anticipated to play a role in 3D food printing. This review aimed to supply a comprehensive summary of CPP and C. pyrenoidosa peptide extraction methods, their functions, and practical applications in various industries. By doing so, it seeks to underpin subsequent research efforts, highlight current research limitations, and identify future research directions in this field.
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•The hydrophobicity of lignin was reduced by pre-adsorbing surfactants.•Amphiphilic surfactant weaken adsorption between lignin and cellulase.•Reducing hydrophobicity of substrate ...promoted its enzymatic digestibility.
In this work, amphiphilic surfactant was obtained using dehydroabietic acid from pine rosin and then pre-adsorbed with acid-pretreated bamboo residues (AP-BR) to block the residual lignin adsorption site, which is expected to improve its enzymatic digestibility. Results from cryogenic-transmission electron microscopy (Cryo-TEM) indicated amphiphilic surfactant with PEG with polymerization degree of 34 (D-34) aggregated to form worm-like micelles, which improved enzymatic hydrolysis yield of AP-BR from 24.3% to 71.9% by pre-adsorbing with 0.8 g/L. Amphiphilic surfactants pre-adsorbed on AP-BR could reduce hydrophobicity of AP-BR, adsorption affinity and adsorption capacity of lignin for cellulase from 0.51 L/g to 0.48–0.32 L/g, from 2.9 mL/mg to 1.8–1.4 mL/mg, and from 122.3 mg/g to 101.9–21.4 mg/g, respectively. These changed properties showed compelling positive contributions (R2 > 0.9) for free enzymes in the supernatants and sequently for final enzymatic hydrolysis yield, which was caused by blocking non-productively hydrophobic adsorption between lignin and cellulase.
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•Levulinic acid based deep eutectic solvent was used for moso bamboo pretreatments.•Crystallinity was effectively reduced along with the biomass matrix removal.•Microvoids in ...horizontal and cracks in longitudinal direction were revealed.•LA-Ch showed optimal hydrolysis performance with highest glucose yield.•LA/Ba DES had better recycle performance due to the capability of lignin extraction.
Discovering green solvents and their inner mechanisms for efficient deconstruction of lignocellulosic biomass recalcitrance are receiving growing interests. In this work, eco-friendly levulinic acid (LA) based deep eutectic solvents (DES) were proposed for pretreatment on moso bamboo by combining acetamide (Am), betaine (Ba) and choline chloride (ChCl) as hydrogen bonding acceptors. LA/ChCl pretreated materials showed optimal enzymatic accessibility with the highest glucose yield (79.07%) because of its higher lignin removal, morphological disruption and decreased crystallinity. Moreover, the microvoids (averagely 30 nm) and cracks were observed for cellulose microfibrils in anisotropic directions, which resulted in shorter microfibrils and crystallites facilitating the enzymatic hydrolysis. The studies on recyclability revealed that LA/Ba DES had better recycling performance due to its maintaining capability of lignin extraction. Series of supramolecular changes on oriented crystalline cellulose were determined in this work by novel LA based DES, which may provide new alternatives for biomass pretreatments.
•Deep eutectic solvent (DES) treatment was conducted on poplar sawdust.•DES is selective removal of lignin and xylan while well retention of most cellulose.•The lignin showed no recondensation, high ...amount of phenolic OH and high purity.•High glucose yield and antioxidative lignin were produced from poplar sawdust.
A promising pretreatment mediated by biomass-derived deep eutectic solvent (DES) with choline chloride to lactic acid was implemented to overcome the recalcitrant structure of poplar sawdust for effective enzymatic hydrolysis and valorized lignin. Results showed the DES applied was strongly selective towards removal of lignin and xylan while preserving cellulose. Under the optimal pretreatment condition (DES ratio: 1:2, temperature: 130 °C, time:1.5 h), the glucose yield from enzymatic hydrolysis was 75.8%. Chemical and structure changes of recovered lignin were evaluated to gauge its valorization potential. It indicated that the recovered lignin possessed molecular weight (4000–6000 g/mol), low polydispersity (PDI < 2.0), low quantity of β-aryl-ethers with no recondensation, and an abundance of phenolic OH groups. The excellent antioxidant capacity of lignin demonstrated its great value as a polyphenolic antioxidant. Overall, this work demonstrated an emerging biorefinery technology method for effective fractionation and valorization of lignocellulosic biomass.
•Enzymatic digestibility of 76.9% was achieved for DES-pretreated bamboo residues.•Changes of cellulose properties made contribute to the enzymatic digestibility.•Enzymatic digestibility linearly ...correlated to change of physicochemical property.
Deep eutectic solvent (DES) is a promising pretreatment for improving enzymatic digestibility of lignocellulosic material by altering the physicochemical properties. However, few work has been done to quantitatively analysis the physicochemical properties changes of lignocellulosic material with enzymatic digestibility. In this work, DES pretreatment with different molar ratios of choline chloride/lactic acid was carried out on bamboo residues and respective enzymatic digestibility was investigated and linearly fitted with corresponding physicochemical features changes of the pretreated bamboo residues. Results showed that enzymatic digestibility of DES-pretreated bamboo residues was enhanced with the increasing molar ratio of choline chloride/lactic acid, which was due to DES pretreatment’s ability to remove lignin and xylan, reduce the degree of polymerization of cellulose, enhance the crystallite size of cellulose, and improve cellulose accessibility. Several compelling linear correlations (R2 = 0.6–0.9) were observable between enzymatic digestibility and these changes of physicochemical properties, demonstrating how DES pretreatment improve the enzymatic digestibility.
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