Cellulose's appeal stems from its crystalline and amorphous polymorphs, while silk's allure lies in its adaptable secondary structure formations, composed of flexible protein fibers. Mixing the two biomacromolecules enables modification of their characteristics, achieved through changes to the materials' composition and production techniques, including choices of solvent, coagulation agent, and temperature settings. Employing reduced graphene oxide (rGO) leads to improved molecular interactions and the stabilization of natural polymers. This study explored the interplay between small rGO concentrations and the crystallinity of carbohydrates, protein secondary structure formation, physicochemical properties, and the ionic conductivity of composite cellulose-silk materials. An investigation into the properties of fabricated silk and cellulose composites, both with and without rGO, was undertaken employing Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy, X-Ray Scattering, Differential Scanning Calorimetry, Dielectric Relaxation Spectroscopy, and Thermogravimetric Analysis. By incorporating rGO, we observed modifications in the morphological and thermal properties of cellulose-silk biocomposites, specifically in cellulose crystallinity and silk sheet content, which consequently affected ionic conductivity, as indicated by our results.
For optimal wound healing, an ideal dressing should exhibit superior antimicrobial action while providing a nurturing microenvironment for the restoration of damaged skin. In this investigation, sericin was employed to synthesize silver nanoparticles in situ, and curcumin was incorporated to develop a novel antimicrobial agent, Sericin-AgNPs/Curcumin (Se-Ag/Cur). A physically double-crosslinked 3D network (sodium alginate-chitosan, SC) served to encapsulate the hybrid antimicrobial agent, yielding the SC/Se-Ag/Cur composite sponge. Sodium alginate's electrostatic engagement with chitosan, and its ionic connection to calcium ions, led to the construction of the intricate 3D structural networks. Prepared composite sponges, exhibiting an impressive hygroscopicity (contact angle 51° 56′), superb moisture retention, notable porosity (6732% ± 337%), and impressive mechanical strength (>0.7 MPa), also demonstrate good antibacterial properties against Pseudomonas aeruginosa (P. aeruginosa). The focus of this investigation was on Pseudomonas aeruginosa, and Staphylococcus aureus, also known as S. aureus. In-vivo analyses have established that the composite sponge promotes the restoration of epithelial tissue and collagen buildup in lesions that have been infected with either Staphylococcus aureus or Pseudomonas aeruginosa. By analyzing tissue immunofluorescence staining, it was observed that the SC/Se-Ag/Cur complex sponge elevated CD31 expression, promoting angiogenesis, and simultaneously reduced TNF-expression, thereby diminishing inflammation. These superior qualities make this material an ideal candidate for infectious wound repair materials, ensuring a robust strategy for clinical cases of skin trauma infections.
An increasing trend is observable in the pursuit of pectin from new origins. The underutilized, yet abundant young apple, thinned, holds the potential to be a source of pectin. This study investigated the extraction of pectin from three thinned-young apple varieties by applying citric acid, an organic acid, and two inorganic acids, hydrochloric acid and nitric acid, frequently used in the commercial pectin extraction process. Detailed analysis encompassed the physicochemical and functional properties of the thinned-young apple pectin. Using citric acid extraction, the highest pectin yield (888%) was achieved from Fuji apples. Pectin samples were entirely composed of high methoxy pectin (HMP), with a prevalence of RG-I regions exceeding 56%. Citric acid extraction yielded pectin with the highest molecular weight (Mw) and the lowest degree of esterification (DE), showcasing remarkable thermal stability and shear-thinning properties. Beyond that, the emulsifying performance of pectin from Fuji apples was markedly superior to that of pectin from the other two apple varieties. The application of pectin, derived from citric acid-treated Fuji thinned-young apples, promises a valuable natural thickener and emulsifier within the food industry.
The use of sorbitol in semi-dried noodles serves the dual purpose of water retention and shelf-life extension. A study on the effect of sorbitol on in vitro starch digestibility was conducted using semi-dried black highland barley noodles (SBHBN) as the material. Experiments on starch digestion in a laboratory setting found that the extent of hydrolysis and the rate of digestion decreased as sorbitol concentration increased, but this inhibitory effect decreased when the concentration surpassed 2%. Compared to the control, a 2% sorbitol supplement led to a substantial drop in equilibrium hydrolysis (C), decreasing from 7518% to 6657%, and a significant (p<0.005) reduction in the kinetic coefficient (k) of 2029%. The incorporation of sorbitol into cooked SBHBN starch resulted in enhanced microstructure tightness, increased relative crystallinity, a more defined V-type crystal structure, improved molecular order, and stronger hydrogen bonding. Meanwhile, the addition of sorbitol to raw SBHBN starch led to an increase in the gelatinization enthalpy change (H). The swelling capacity and amylose leaching from SBHBN were lessened when sorbitol was added. Short-range ordered structure (H) exhibited significant (p < 0.05) correlations, as revealed by Pearson correlation analysis, with related in vitro starch digestion indices of SBHBN samples supplemented with sorbitol. From these outcomes, sorbitol's potential to form hydrogen bonds with starch was noted, suggesting its feasibility as an additive to reduce the glycemic impact in starchy food types.
Ishige okamurae Yendo's sulfated polysaccharide, termed IOY, was successfully isolated via sequential anion-exchange and size-exclusion chromatographic steps. Spectroscopic and chemical analyses indicated that IOY's structure was fucoidan, containing 3',l-Fucp-(1,4),l-Fucp-(1,6),d-Galp-(1,3),d-Galp-(1) residues, bearing sulfate groups at positions C-2/C-4 of the (1,3),l-Fucp and C-6 of the (1,3),d-Galp components. Lymphocyte proliferation in response to IOY, as measured in vitro, revealed a potent immunomodulatory effect. Cyclophosphamide (CTX)-induced immunosuppression in mice served as a model for further in vivo investigation into the immunomodulatory effects of IOY. Clofarabine The observed outcomes revealed that IOY treatment led to a substantial rise in spleen and thymus indices, counteracting the negative effects of CTX on the integrity of these organs. Clofarabine Furthermore, the effect of IOY extended to significantly improving hematopoietic function recovery, along with stimulating the production of interleukin-2 (IL-2) and tumor necrosis factor (TNF-). Furthermore, IOY's intervention successfully reversed the reduction in CD4+ and CD8+ T-cell counts, and improved immune function. The data revealed IOY's crucial role in immunomodulation, suggesting its potential as a therapeutic drug or functional food to mitigate chemotherapy-induced immunosuppression.
The fabrication of highly sensitive strain sensors has found a promising material in conducting polymer hydrogels. The poor adhesion between the conducting polymer and the gel network, unfortunately, typically compromises the stretchability and introduces substantial hysteresis, thus limiting its functionality in wide-range strain sensing. We employ hydroxypropyl methyl cellulose (HPMC), poly(3,4-ethylenedioxythiophene)poly(styrenesulfonic acid) (PEDOT:PSS), and chemically cross-linked polyacrylamide (PAM) to generate a strain sensor-applicable conducting polymer hydrogel. Because of the numerous hydrogen bonds between HPMC, PEDOTPSS, and PAM chains, the conducting polymer hydrogel exhibits a strong tensile strength of 166 kPa, an exceptionally high stretchability of more than 1600%, and a low hysteresis of less than 10% at 1000% cyclic tensile strain. Clofarabine Exceptional durability and reproducibility characterize the resultant hydrogel strain sensor, which also boasts ultra-high sensitivity and a wide strain sensing range of 2% to 1600%. This strain sensor, when worn, can track intense human activity and nuanced physiological changes, functioning as bioelectrodes for both electrocardiography and electromyography. This study opens up novel design possibilities for conducting polymer hydrogels, crucial for high-performance sensing device applications.
The presence of heavy metals in aquatic ecosystems, a significant pollutant, results in harmful effects on human health when the metals are absorbed through the food chain. Given its significant specific surface area, high mechanical strength, biocompatibility, and low production cost, nanocellulose stands as a compelling environmentally friendly renewable resource for removing heavy metal ions, competing effectively with other materials. This review focuses on the current state of research regarding modified nanocellulose as heavy metal adsorbents. Among the various forms of nanocellulose, cellulose nanocrystals (CNCs) and cellulose nanofibers (CNFs) are prominent. The method of preparing nanocellulose is rooted in natural plant materials; this process necessitates the elimination of non-cellulosic constituents and the extraction of nanocellulose. The exploration of nanocellulose modification strategies, particularly to enhance heavy metal adsorption, included direct modification approaches, surface grafting techniques facilitated by free radical polymerization, and the application of physical activation. A detailed analysis of the adsorption principles of nanocellulose-based adsorbents in the removal of heavy metals is presented. The deployment of modified nanocellulose in heavy metal removal applications could be enhanced by this review.
Due to inherent characteristics, such as flammability, brittleness, and low crystallinity, poly(lactic acid) (PLA) has limited broad applications. To achieve enhanced fire resistance and mechanical properties of PLA, a chitosan-based core-shell flame retardant additive, APBA@PA@CS, was created through the self-assembly of interionic interactions between chitosan (CS), phytic acid (PA), and 3-aminophenyl boronic acid (APBA).