International Journal of Biological Macromolecules最新文献

The Atlantic blue crab (Callinectes sapidus), an invasive species spreading in the Mediterranean, produces substantial shell by-products. This study examines the impact of thermal pre-treatment (cooking) on the extraction and physicochemical properties of chitin from crab carapaces. Fresh and cooked samples were subjected to a stepwise acid-alkali protocol under mild conditions. The resulting chitins were evaluated through gravimetric yield and multiparametric characterisation, including Fourier-transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, and nuclear magnetic resonance. In both samples, the results confirmed the α-chitin allomorph with a high degree of acetylation (≈ 97%), identical molecular features, and a 35% degree of crystallinity. Morphological analysis revealed similar fibrillar architectures with local porosity and a more compact organisation in chitin from cooked carapaces. Chitin in cooked samples had a lower ash content (1.2%) compared to fresh samples (13.4%), indicating higher purity. Chitin recovery was significantly higher for cooked carapace (~17%) than for fresh carapace (~14%) (p < 0.05). Overall, thermal pretreatment enhances demineralisation efficiency, enabling effective chitin recovery under diluted acid conditions. This study demonstrates that cooked blue crab carapaces provide a more efficient feedstock for industrial chitin production, supporting circular bioeconomy strategies to valorise invasive species.

Oily wastewater poses significant ecological hazards, necessitating the development of effective, reusable, and environmentally friendly sorbent materials for efficient oil/water separation. Here, we report the fabrication of a superhydrophobic aerogel composed of gellan gum (GG), konjac glucomannan (KGM), and bamboo fiber (BF), cross-linked with 1,4-butanediol diglycidyl ether (BDGE), and engineered into a hydrophobic cuttlebone-like structure via directional freeze-drying and vapor-phase deposition. The resulting superhydrophobic aerogel (H-GG/KGM/BF) exhibits a porosity of 98.46% and a density of 0.02354 g·cm^-3, with an excellent sorption capacity ranging from 18.08 to 75.66 g·g^-1, and it undergoes complete biodegradation within 3 weeks. It demonstrates superhydrophobicity and oil affinity, attributable to its porous lamellar architecture and S-shaped cross-section pillars, which also confer high compressibility and durability over 30 compression cycles at 30% strain. In addition to oil sorption, the material enables continuous oil/water separation with an efficiency of 98.7% and a flux exceeding 4700 L·m^-2·h^-1, highlighting its potential as a reusable sorbent for environmental remediation.

In this study, a multifunctional superabsorbent hydrogel with synergistic effects of water retention, slow-release fertilizer, and metal-ion adsorption capabilities was synthesized through a green, one-step irradiation method (γ-SAHs). The synthesis was conducted at room temperature without initiators or crosslinking agents, using potato soluble starch (PSS, 0.5-5 g) and acrylic acid (AA, 5 mL) as raw materials, with urea (1-4 g) incorporated (urea/PSS-g-PAA) to enhance physical crosslinking and enable controlled-release fertilization. The addition of PSS and urea significantly increased the cross-linking density and porosity of the hydrogel. As a result, urea/PSS-g-PAA exhibited improved water retention, salt tolerance and broader pH adaptability. Plant growth experiments in sandy soil demonstrated that γ-SAHs effectively retained moisture, reduced evaporation, and substantially promoted maize growth under dry conditions. The hydrogel displayed segmented urea-release kinetics, offering a safe germination environment followed by a sustained nutrient supply. Degradation experiments further confirmed the synergy between the degradability of γ-SAHs and their metal-ion adsorption capacity, with a maximum Cu²⁺ ions adsorption capacity of 84.37 mg/g. With its integrated functions, this material demonstrates great potential for sustainable agriculture and ecological restoration in arid regions.

The widespread contamination of water by dyes, pharmaceuticals, and pathogenic microorganisms poses a major global challenge, creating an urgent need for efficient and environmentally friendly remediation materials. This study reports a multifunctional hybrid adsorbent composed of chitosan, gelatin, stone wool, and ulexite for the removal of crystal violet and norfloxacin, and the adsorption of two bacterial strains (Escherichia coli and Staphylococcus aureus) from aqueous solutions. The adsorbent was synthesized via a cryogelation process and comprehensively characterized using FTIR, XPS, SEM-EDS, Micro-CT, gas adsorption, AFM, DMA, and cytotoxicity analyses. The results confirmed a uniform elemental distribution, preserved structural integrity, strong mechanical stability, a hybrid porous architecture, and non-cytotoxic behaviour. Response Surface Methodology was employed to identify statistically significant variables and optimize the adsorption process for crystal violet and norfloxacin. The adsorbent has maximum adsorption capacities of 192.7 mg g^-1 for crystal violet and 12.8 mg g^-1 for norfloxacin, 7.9 × 10⁹ CFU g^-1 for E. coli and 1.1 × 10¹⁰ CFU g^-1 for S. aureus. Adsorption isotherms for crystal violet and norfloxacin were best described by the Langmuir model, indicating monolayer adsorption on a homogeneous surface. Kinetic data followed the pseudo-second-order model, suggesting a surface-controlled rate-limiting step. Thermodynamic analysis revealed that the adsorption process was spontaneous and endothermic. Owing to its high mechanical integrity and reusability, the developed composite is a promising candidate for the adsorption of organic, pharmaceutical, and biological contaminants from water systems.

CCCH-type zinc finger proteins are emerging regulators of plant stress adaptation, yet their functions remain largely unexplored in Tartary buckwheat (TB), an important stress-tolerant crop. Here, we identified 71 FtCCCH genes and classified them into six subfamilies. Phylogenetic and expression analyses highlighted FtCCCH56, a nuclear-localized member of subfamily VI, as the gene most strongly induced under drought stress. Promoter activity assays confirmed that FtCCCH56 is activated by drought, salinity, and abscisic acid (ABA). Functional characterization in TB hairy roots and transgenic Arabidopsis thaliana demonstrated that FtCCCH56 overexpression enhances drought and salt tolerance. Overexpressing lines exhibited greater biomass, higher survival rates, and improved recovery from stress compared to the wild type. Physiological analyses revealed that FtCCCH56-overexpressed plants accumulated more proline, displayed reduced malondialdehyde contents, and maintained stronger antioxidant enzyme activity, thereby alleviating oxidative damage. Additionally, FtCCCH56 overproduction upregulated ABA-responsive genes (AtRD29A, AtRD29B, AtRAB18, AtRD22, AtKIN1, AtCOR15A), as well as genes involved in antioxidant enzyme and proline biosynthesis. This study establishes FtCCCH56 as a positive regulator of drought stress though coordinating ABA signaling, antioxidant activation, and proline-mediated osmo-protection, providing a promising candidate gene for improving crop resilience under abiotic stress.

Legume and cereal proteins, as highly representative plant proteins, often face certain limitations in large-scale application, primarily due to their low digestibility, potential allergenicity, and poor techno-functional properties. Cold plasma technology (CPT) has emerged as a promising non-thermal protein modification method owing to its efficiency, mildness, and environmental friendliness. This paper systematically reviews the CPT systems commonly used in the modification of legume and cereal proteins and their mechanisms of action and comprehensively discusses the positive effects of CPT on protein digestibility, allergenicity, and techno-functional properties. Furthermore, it highlights the enhanced application performance of CPT in legume and cereal protein-based edible films and nanoparticles. Future research should systematically compare the effects of different CPT types on the modification of legume and cereal proteins, optimize key processing parameters, and explore synergistic combinations with other technologies to develop tailored treatment protocols. Overall, this review provides systematic insights and offers novel technical references for addressing core bottlenecks in promoting the high-value and sustainable applications of legume and cereal proteins in food industry.

Potato flour (PF) is rich in starch, high-quality protein, a variety of vitamins and minerals. However, the natural starch in PF is insoluble in water, restricting its use in the food industry. High hydrostatic pressure (HHP) technology modifies the macromolecular structure of starch-rich and protein-rich raw materials, thereby altering their functional properties. Unfortunately, the modification effect of HHP on multi-component PF is still unclear. Therefore, in order to clarify the level of HHP that can improve the processing characteristics of PF, the changes of PF properties under different HHP were studied in this paper. Compared to the control, the water holding capacity and solubility of PF treated with 300 MPa increased by 0.52 g/g and 4.31%, respectively. The result showed that 300 MPa treatment increased the solubility of PF. HHP treatment (100-500 MPa) reduced the thermal stability of PF. However, the thermal stability of PF remained relatively stable at pressures 300 MPa, indicating that functional properties can be improved without compromising thermal resistance. Additionally, the rheological properties of PF gel showed that 300 MPa treatment significantly improved the viscoelasticity of PF gel. Meanwhile, the hardness, chewiness and cohesiveness of the PF gel remained moderate under this treatment. Thus, 300 MPa treatment could improve the processing performance of PF to a certain extent, which provided a reference for the application of HHP technology in potato flour-based food.

The precise targeting of drug molecules to their site of action remains a critical unmet need in pharmaceutical and biomedical science. The nasal route, with its high vascularity, large surface area, and epithelial permeability, enables rapid absorption and has emerged as a promising non-invasive alternative administration pathway for drugs with low oral bioavailability and for sensitive biomolecules such as proteins, peptides, steroids, and vaccines. However, due to several factors including limitation of drug molecular weight, nasal physiology, enzymatic degradation, mucociliary clearance, limited dose, rapid absorption and clearance, nasal routes face challenges for targeted delivery. Compared to conventional polymers, biopolymers have emerged as they are biodegradable, biocompatible, non-toxic, non-immunogenic, prolongs blood circulation, and improves drug loading capacity for both macro and micro-sized molecules. This review summarizes the key biological, physicochemical, and device-related factors governing drug and biomolecule permeability across the nasal mucosa. Additionally, we have discussed the physicochemical, mechanical, and biological fate of various biopolymers and have highlighted recent advances in biopolymer-based nasal delivery systems. Moreover, emphasis is placed on polysaccharide- and protein-based biopolymeric systems specifically tailored to enhance biomacromolecule trafficking through nasal tissues toward both central nervous system and systemic targets.

Dietary polysaccharides can sequester bile acids, thereby supporting cholesterol regulation and cardiovascular health, yet the structural determinants of this interaction remain insufficiently defined. In this study, kiwifruit polysaccharides (KFP) were extracted and systematically subjected to simulated gastrointestinal digestion, colonic fermentation, controlled acid hydrolysis, and rheological modulation to evaluate the contributions of key structural features to bile acid-binding capacity (BABC). Sequential digestion and fermentation showed that intestinal digestion and early-stage fermentation enhanced BABC, coinciding with enrichment of uronic acids, particularly galacturonic acid, whereas prolonged fermentation diminished activity. Molecular weight (Mw) analysis revealed a threshold effect: moderate depolymerization optimized BABC by exposing functional groups and increasing accessibility, while excessive Mw reduction disrupted structural integrity and weakened binding. Viscosity further modulated bile acid binding in an Mw-dependent manner: lower viscosity improved BABC in high- and intermediate-Mw polysaccharides but reduced binding when Mw was extensively degraded. Collectively, these findings demonstrate that BABC is governed by the interplay of uronic acid content, Mw, and viscosity, rather than by any single parameter. This work provides mechanistic insight into KFP structure-function relationships and offers a rational framework for developing kiwifruit-derived functional foods or nutraceuticals targeting cholesterol management.