International Journal of Biological Macromolecules最新文献

Enhancing the hemostatic efficacy and minimizing blood loss in the body has consistently been a primary objective for researchers. This study improved the hemostatic efficacy and tissue adhesion strength of the hemostatic material by augmenting the aldehyde groups in the side chains of sodium alginate. Additionally, it immobilized the aldehyde-modified sodium alginate onto the surface of the hemostatic material through complexation with iron ions, thereby enhancing its antibacterial properties. The mechanical performance results demonstrated that the composite hemostatic sponge can rapidly absorb water, swell to counteract arterial blood pressure, and seal the bleeding wound. The results of tissue and blood cell adhesion and in vivo hemostasis showed that the composite hemostatic sponge can enhance the rate of blood clot formation and the adhesion strength of tissue, thereby reducing the hemostasis time and blood loss. The bacterial and cell growth results demonstrated that the composite hemostatic sponge displays excellent biocompatibility and antibacterial properties. Based on the excellent water absorption, swelling properties, and softness of cellulose sponge, the composite hemostatic sponge offered a significant advantage for achieving rapid hemostasis in penetrating wounds or deep wounds with substantial bleeding.

The increasing need for convenient, fast, and nutritious of prepared foods elevate the development of biodegradable antibacterial packaging materials with excellent performance. Inspired by the brick-cement-like system, the two-dimensional nanomaterial Ti₃C₂ MXene as nanofillers with optothermal response function was employed to strength the performance of chitosan/gelatin/polyvinyl alcohol composite films (CGPF-Mxs). The results revealed that the high-modulus Ti₃C₂ MXene material improved the microstructures density of macromolecule polymers by physical interactions, as well as enhancements in mechanical properties, thermal stability, barrier properties, water resistance, and antioxidation performance of the composite films. The composite film with 0.75 % Ti₃C₂ MXene demonstrated the optimal performance. Additionally, the composite films exhibited efficient photothermal effect, which showed inhibition rate of 98.53 % for Staphylococcus aureus and 82.91 % for Escherichia coli under near-infrared laser. The proposed film revealed a potential application as packaging material for maintaining the quality of cooked meat products.

The preparation of intelligent indicator films containing anthocyanins and their utilization for real-time monitoring of meat freshness represents a prominent research topic of food packaging. In this study, anthocyanins (ALR) were extracted from Lycium ruthenicum (LR) using solvent extraction. Subsequently, these anthocyanins were incorporated into films composed of soybean isolate protein (SPI), xanthan gum (XG) and agar, resulting in SPI/XG/Agar-ALR pH-responsive intelligent indicator films. The physical properties, structural characterization and application in mutton preservation were evaluated to identify the intelligent indicator films with the optimal addition ratio of ALR. The results indicated that the SPI/XG/Agar-5 % films exhibited exceptional performance in terms of thickness, mechanical properties, water vapor transmission rate, oxygen transmission rate and light transmission rate. Scanning electron microscope observations revealed that the SPI/XG/Agar-5 % films possessed a smooth and flat surface, while fourier transform infrared spectroscopy analysis confirmed their excellent compatibility. The DPPH radical scavenging rate of the SPI/XG/Agar-5 % film reached 80.75 ± 0.63 %. When applied to the preservation of mutton, the SPI/XG/Agar-5 % film significantly extended the shelf life and effectively monitored the freshness of the meat. This study not only broadens the application scope of Lycium ruthenicum anthocyanins but also provides a foundation for the development of smart packaging materials.

The signal peptides GVMGFO and GFOGER exhibit differential binding affinities towards Michigan Cancer Foundation-7 (MCF-7) breast cancer cells and HT-1080 human fibrosarcoma cells, respectively, which in turn modulate the cell adhesion properties of natural collagen. GVMGFO demonstrates a more potent interaction with discoidin domain receptor 1(DDR1)-expressing MCF-7 cells, whereas GFOGER preferentially binds to the integrin α2β1 present on HT-1080 cells. The integration of GVMGFO into natural collagen through direct doping or crosslinking markedly enhances its association with MCF-7 cells, especially when optimal peptide concentrations and blending ratios are utilized, indicating a synergistic effect. This augmented adhesion is attributed to specific binding at the DDR1-collagen interface, facilitated by a constellation of amino acids within the collagen scaffold engaging with the DDR1 discoidin (DS) domain through polar interactions and hydrogen bonding. Conversely, the incorporation of GFOGER into natural collagen through co-assembling or crosslinking leads to a progressive increase in adherence to HT-1080 cells, as evidenced by the peptide's affinity for integrin α2β1. These findings advance the design of collagen-based biomaterials for targeted cellular interactions in the medical, pharmaceutical, and enhance our understanding of the molecular mechanisms governing peptide-collagen mediated cell adhesion processes.

Cotton fibers' flammability and rapid combustion greatly restrict their usage in industries that require higher flame retardancy. Phosphorus and nitrogen-based flame retardants are frequently employed in the textile industry to consolidate the flame resistance of cotton materials. To consolidate flame retardant performance, a novel flame retardant named HPAPU was synthesized by combining 3-hydroxyphenylphosphinylpropionic acid, 1,6-hexanediamine, phosphoric acid, and urea. The structure of the products at each step was analyzed using Fourier transform infrared spectroscopy. In addition, the NMR was utilized to confirm that it was successfully synthesized. In order to evaluate the flame retardancy of HPAPU-treated cotton fabrics, the limiting oxygen index (LOI) was measured. The results showed that the LOI of the cotton fabric with 27.5 % weight gain was 38.5 %, which is a significant increase compared to the pure cotton fabric. According to the cone calorimeter test, the HPAPU-treated cotton fabrics showed a decrease in 86.6 % in peak heat release rate and 41.67 % in peak total heat release rate compared with unprocessed samples. In the tensile test, we found that increasing the flame-retardant concentration can improve the fabrics' tensile strength.

The plant cell wall is a crucial barrier against environmental stress, mainly composed of lignin and carbohydrates such as cellulose, hemicellulose, and pectin. This study explored the direct regulatory mechanism of silicon (Si) on cell wall components of Glycyrrhiza uralensis (G. uralensis) stems under salt and drought (S + D) stress and the indirect regulatory mechanism of non-structural carbohydrates on structural carbohydrates, mediated by uridine diphosphate glucose (UDPG), through joint physiological, biochemical, and transcriptomic analyses. Under S + D stress, Si increased the contents of cell wall components, altered the structure of cell wall, and directly promoted cell wall re-construction by regulating gene expression levels and enzyme activities related to cell wall biosynthesis. Meanwhile, Si facilitated the accumulation of carbohydrates by regulating enzyme activities and gene expression levels in the anabolic pathway of polysaccharides, thereby promoting UDPG conversion and indirectly providing substrates for cell wall synthesis. In conclusion, Si directly and indirectly facilitates the synthesis of cell wall components by regulating both cell wall metabolism and non-structural carbohydrates metabolism, thus reinforcing the cell wall, enhancing its stability, and improving the salt and drought tolerance of G. uralensis stems.

Hyaluronic acid (HA) has multiple biological activities which are closely related to its molecular weight. In the present study, the photoelectrocatalytic method was established for HA degradation and the influences of bias potentials, H₂O₂ additions and reaction times on the degradation results were investigated to optimize the reaction condition. Moreover, a series of analysis methods, such as FT-IR and NMR were used to analyze chemical compositions of the degradation products, revealing that photoelectrocatalytic degradation did not damage the structural blocks of HA obviously. Then 11 oligosaccharides with polymerization degrees from 2 to 8 in the degradation products were identified by mass spectroscopy and their reducing ends were all GlcA or AraA. In addition, in the photoelectrocatalytic degradation of HA, ·OH were identified as the most influential among the produced free radicals, and it could be proposed that ·OH specifically targeted the anomeric carbon of GlcA, resulting in the disaggregation of polysaccharides chain. Furthermore, the results of in vitro fermentation with fecal microbiota demonstrated that HA and its degradation products regulated microbiota structure discriminately, indicating their possible different outcomes as nutritional supplements and agents.

Polymer and nanoparticles (NPs) together are able to form nanocomposite materials that combine the beneficial properties of the traditional single systems. In this work, we propose a stimuli-responsive nanocomposite system which combines pH-responsive NPs with cellulose. Ring opening polymerization (ROP) followed by two reversible addition-fragmentation chain transfer (RAFT) polymerization steps were performed to synthetize ((PHEMA-graft-LA₁₂)-co-PMAA)-b-PDEGMA copolymer characterized by tailored molecular weights and low polydispersity values. Uniform NPs were obtained by nanoprecipitation of the so-obtained copolymer in water. Moreover, drug release studies (using rhodamine b, fluorescein isothiocyanate, pyrene and 5-fluorouracil) at different pHs demonstrated the pH-responsivity of NPs, revealing a significant improvement of hydrophobic molecules release at acidic conditions. In vitro tests verified the biocompatibility of NPs and the efficacy in decreasing cancer cell viability. Finally, NPs were loaded into hydroxypropylmethyl-cellulose-C₁₂ matrix to obtain the final polymer-NPs composite system. The composite systems showed the ability to sustain the release of low steric hindrance drugs loaded with NPs and high steric hindrance ones loaded within the polymeric network. Overall, the proposed pH-responsive drug delivery system represents a co-delivery device which could be applied for localized treatment in different combined therapeutic program.