Search Results (405)

The present study aims to optimize the extraction process and systematically investigate the bioactivity of polysaccharides derived from Peristrophe roxburghiana (Schult.) Brem. (CPPRs). To this end, the Box–Behnken design–response surface methodology was employed to optimize the extraction parameters of polysaccharides. The optimal extraction conditions were as follows: extraction temperature, 84 °C; extraction duration, 208 min; liquid-to-material ratio, 1:27 g/mL; extraction times, 4 times. The maximum extraction yield reached 17.89%, and the yield under non-optimal extraction conditions is 11–16%. This study systematically investigated the polysaccharides’ physicochemical, structural, and morphological properties using multiple advanced techniques (FTIR, SEM, XRD, HPLC, rheology, and TGA). CPPRs are primarily composed of arabinose, galactose and glucose as the main monosaccharides, amorphous, and capable of low-viscosity gels at low shear rates. Furthermore, CPPRs displayed notable antioxidant activity in vitro, scavenging ABTS^•+ and DPPH^• and reducing Fe³⁺ (with scavenging/reducing rates exceeding 40% at a concentration of 1 mg/mL). Meanwhile, 3 mg/mL CPPRs reduced oxidative damage of red blood cells induced by AAPH, scavenging more than 50% of ROS, and reducing the hemolysis rate by 94.5%. Additionally, CPPRs significantly promoted secretion of cytokines (including TNF-α, IL-6, and IL-10) and NO in RAW264.7 macrophages in vitro compared with the untreated control group. These findings collectively highlight the potential of CPPRs—possessing both antioxidant and immune-enhancing properties—as promising functional ingredients for application in the food and pharmaceutical industries. Full article

Rapid urbanization and industrialization have increased atmospheric pollution, particularly via sulfur oxides (SO_x) that form sulfuric acid and accelerate the degradation of cementitious materials. While Portland-cement systems have been widely studied, less is known about the acid resistance of geopolymer mortars. This study investigates the durability and microstructural evolution of metakaolin–red mud geopolymer mortars incorporating limestone, marble, and basalt powders as partial sand replacements (5, 10, and 15 wt %). Specimens were immersed in 3% H₂SO₄ for 30, 60, and 90 days, with performance evaluated via compressive and flexural strength, weight loss, and ultrasonic pulse velocity (UPV), alongside scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). After 90 days, the optimal basalt-filled mix (15 wt %) retained 84% of its initial compressive strength (46.8 MPa), compared with 61% for the control; mass loss decreased from 6.4% (control) to 3.2%, and UPV degradation was reduced by 35%. Microstructural analyses indicate denser gel phases and reduced microcracking in basalt- and marble-filled mixes. These results demonstrate that industrial by-product fillers can significantly improve sulfuric-acid resistance while supporting more sustainable binder technology. Full article

To address the environmental risks associated with large-scale stockpiling of red mud (RM) and coal gangue (CG) and the demand for their high-value utilization, this study proposes a ternary concrete system incorporating RM, fly ash (FA), and CG aggregate. The effects of RM content, FA content, CG aggregate replacement rate, and water-to-binder ratio on workability, mechanical properties, and frost resistance durability were systematically investigated through orthogonal experiments, with the underlying micro-mechanisms revealed by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The results indicate that workability is predominantly governed by the water-to-binder ratio, while the micro-aggregate effect of FA significantly enhances fluidity. Mechanical properties are most significantly influenced by RM content; under a 20% CG aggregate replacement rate and a 0.45 water-to-binder ratio, an optimal compressive strength was achieved with a low content combination of RM and FA. Frost resistance deteriorated markedly with increasing RM and FA content, with the high-content group approaching the failure threshold after only 25 freeze–thaw cycles, occurring 50 and 125 cycles earlier than the medium- and low-content groups, respectively. Macro-micro results indicate a synergistic threshold at 20% red mud and 45% fly ash, yielding a compressive strength of 24.96 MPa. This value exceeds the 24.87 MPa of the 10% red mud + 45% fly ash group and the 21.90 MPa of the 10% red mud + 55% fly ash group. Microstructurally, this group also exhibits superior C-S-H gel uniformity and narrower crack widths compared to the others. Excessive incorporation of red mud and fly ash leads to agglomeration of unhydrated particles and increased porosity, aligning with the observed macroscopic strength degradation. This research identifies and quantifies the synergistic threshold governing RFCTSWC performance evolution, providing theoretical support for engineering applications of solid waste concrete. Full article

This study aimed to develop a functional powder using whey and milk matrices, leveraging the protective capacity of chia–alginate hydrogels and the advantages of electrohydrodynamic spraying (EHDA), a non-thermal technique suitable for encapsulating probiotic cells under stress conditions commonly encountered in food processing. A hydrogel matrix composed of chia seed mucilage and sodium alginate was used to form a biopolymeric network that protected probiotic cells during processing. The encapsulation efficiency reached 99.0 ± 0.01%, and bacterial viability remained above 9.9 log₁₀ CFU/mL after lyophilization, demonstrating the excellent protective capacity of the hydrogel matrix. Microstructural analysis using confocal laser scanning microscopy (CLSM) revealed well-retained cell morphology and homogeneous distribution within the hydrogel matrix while, in contrast, scanning electron microscopy (SEM) showed spherical, porous microcapsules with distinct surface characteristics influenced by the encapsulation method. Encapsulates were incorporated into beverages flavored with red fruits and pear and subsequently freeze-dried. The resulting powders were analyzed for moisture, protein, lipids, carbohydrates, fiber, and color determinations. The results were statistically analyzed using ANOVA and response surface methodology, highlighting the impact of ingredient ratios on nutritional composition. Raman spectroscopy identified molecular features associated with casein, lactose, pectins, anthocyanins, and other functional compounds, confirming the contribution of both matrix and encapsulants maintaining the structural characteristics of the product. The presence of antioxidant bands supported the functional potential of the powder formulations. Chia–alginate hydrogels effectively encapsulated L. reuteri, maintaining cell viability and enabling their incorporation into freeze-dried beverage powders. This approach offers a promising strategy for the development of next-generation functional food gels with enhanced probiotic stability, nutritional properties, and potential application in health-promoting dairy systems. Full article

The removal of iron deposits on shipwreck surfaces by mechanical cleaning is labour-intensive work. This study develops an in situ gel and peeling cleaning method, utilising a carboxymethyl chitosan/tannic acid (CMCS/TA) colloidal solution spray on the surface of ferruginous deposits, promoting their removal by adhesion, chelation, and electrostatic bonding processes. The investigation confirmed that the CMTA-2 sample exhibited a sprayable viscosity of 263 mPa/s, the largest single removal thickness of 1.01 mm, a significant reduction in the fe/s atomic ratio by 2.53 units, and enhanced the deposit removal homogeneity. The field testing of the Nanhai I cultural relic showed a 14.37% reduction in iron concentration and a significant decrease in red colour (Δa* = 4.36). The synergistic mechanism involves TA chelating Fe²⁺/Fe³⁺ ions, while the CMCS gel network facilitates interfacial adhesion and mechanical peeling, hence promoting efficient and controllable cleaning. Full article

Innovative plant protection solutions are increasingly sought in modern agriculture. Rapid advances in nanotechnology offer promising opportunities to develop biodegradable, cost-effective composites containing silver nanoparticles (AgNPs) with well-documented antimicrobial properties. The aim of this study was to synthesize sodium alginate gels containing AgNPs, evaluate their physicochemical and antibacterial properties, and assess their effect on the growth of red cabbage (Brassica oleracea var. capitata f. rubra) seedlings. In accordance with the principles of green chemistry, AgNPs were chemically synthesized using sodium alginate as a stabilizer and fructose as a non-toxic reducing agent. The final composite contained 150 mg/L AgNPs and was diluted to 20 and 60 mg/L for biological tests. Antibacterial activity against Bacillus cereus, Enterococcus faecalis, Escherichia coli, and Pseudomonas aeruginosa was tested using agar diffusion assays. Seedling growth parameters and phytochemical content were assessed after 10 days of seedlings exposure to AgNPs. The results showed significant antibacterial activity in all tested strains. Crucially, neither AgNPs concentration negatively affected seedling development or phytochemical concentration. Application of AgNPs at concentration of 60 mg/L increased ascorbic acid and carotenoids content in comparison to control (deionized water). These results suggest that AgNPs-alginate composites may serve as sustainable antimicrobial agents in agriculture, inhibiting pathogens without compromising crop quality. Full article

Red mud, a highly alkaline industrial by-product generated during aluminum smelting, poses serious environmental risks such as soil alkalization and ecological degradation. In this study, response surface methodology (RSM) was integrated with advanced microstructural characterization techniques to optimize the performance of red mud–slag composite cementitious materials through multi-factor analysis. By constructing a four-factor interaction model—including red mud content, steel fiber content, alkali activator dosage, and calcination temperature—a systematic mix design and performance prediction framework was established, overcoming the limitations of traditional single-factor experimental approaches. The optimal ratio was determined via multi-factor RSM analysis as follows: the 28-day flexural strength and compressive strength of the specimens reached 12.26 MPa and 69.83 MPa, respectively. Furthermore, XRD and SEM-EDS analyses revealed the synergistic formation of C-S-H and C-A-S-H gels, and their strengthening effects at the fiber–matrix interfacial transition zone (ITZ), elucidating the micro-mechanism pathway of “gel densification–rack filling–strength enhancement.” This work not only enriches the theoretical foundation for the design of red mud-based binders but also offers practical insights and empirical evidence for their engineering applications, highlighting substantial potential in the development of sustainable building materials and high-value utilization of industrial solid waste. Full article

This study investigates the influence of different light sources (sunlight, green, red, and white LED) on the germination of Raphanus sativus L. sprouts and the potential use of their sprout extracts in the development of natural dermatocosmetic gels. The bioactive fractions were extracted using simple methods and analyzed for total polyphenol content and antioxidant activity. Statistical analysis of weight, total phenolic content, and antioxidant activity of Raphanus sativus L. sprouts was performed using ANOVA. Sprouts exposed to green LED light showed the highest biomass (16.13 ± 0.38 g), while red LED light resulted in the highest total polyphenol content (3.28 ± 0.03 mg GAE/g fresh weight). The highest antioxidant activity (6.60 ± 0.08 mM Trolox/g fresh weight) was obtained under white LED. Although variations were observed, ANOVA analysis revealed that only sprout weight differed significantly among treatments (p < 0.001), while differences in polyphenol content and antioxidant activity were not statistically significant (p > 0.05). The extract with the highest antioxidant activity was incorporated as an active ingredient into Carbopol-based hydrogel formulations containing natural gelling agents and gentle preservatives. The resulting gels demonstrated favorable pH (4.85–5.05), texture, and stability. The results indicate that the light spectrum influences the germination process and the initial development of seedlings. Moreover, radish sprout extracts, rich in bioactive compounds, show promise for dermatocosmetic applications due to their antioxidant, soothing, and antimicrobial properties. This study supports the use of natural resources in the development of care products, in line with current trends in green cosmetics. Full article

High oil content in breaded fried small yellow croaker (BFYC) was reduced using composite batter gels consisting of tapioca starch, wheat flour, and different concentrations of cassia gum (CG; 0%, 0.2%, 0.4%, 0.6%, 0.8%, 1%). The effects of CG on the oil absorption capacity of BFYC and potential mechanisms were investigated. Dynamic rheological analysis revealed that CG addition could enhance the viscoelasticity of the batter by increasing its storage modulus and loss modulus. Furthermore, FTIR and X-ray diffraction results demonstrated that CG interacts with starch through noncovalent interactions, increasing the relative crystallinity from 9.29% to 16.49%, which promoted the formation of a gel layer. This structural improvement effectively inhibited oil absorption. Differential scanning calorimetry analysis showed that within the 0–0.8% CG range, the batter’s denaturation temperature increased from 78.23 °C to 82.08 °C with higher CG concentrations, indicating prolonged gelatinization and enhanced thermal stability that further reduced oil penetration. Low-field nuclear magnetic resonance analysis revealed that CG increased the proportion of tightly bound and weakly bound water in the batter, thereby improving water retention capacity and reducing moisture loss during frying. Microscopic structural observations and Sudan Red-staining tests confirmed that at 0.8% CG concentration, the crust exhibited the lowest porosity with approximately 40% reduction in surface fat content compared to the control group. In conclusion, CG addition significantly improves batter properties and reduces oil content in fried products, providing theoretical support for the development of low-fat fried foods. Full article

The enzyme transglutaminase 2 (TG2) has an open conformation with transamidase activity which crosslinks matrix proteins contributing to fibrosis development. LDN-27219 promotes the closed conformation of TG2, which can enhance vasodilation, but its effects in renal tissue are unknown. We investigated whether LDN-27219 treatment affects albuminuria and markers of renal fibrosis as well as ex vivo vasodilatation. Male C57BL/6 mice (n = 48) underwent unilateral nephrectomy plus insertion of a deoxycorticosterone acetate pellet (DOCA group) or nephrectomy only (sham group). Both groups were randomized to intraperitoneal treatment with either LDN-27219 (8 mg/kg twice daily) or vehicle for 2 weeks. Urine albumin excretion was evaluated by metabolic cages. Kidney tissue fibrosis markers were assessed by qPCR and Western blotting, while the TG2 conformational state was evaluated using native gel electrophoresis. Collagen staining was performed using Picrosirius red and quantified under circularly polarized light. Mesenteric arteries were mounted in wire myographs for evaluation of vasorelaxation. DOCA mouse developed significant albuminuria (p < 0.001 vs. sham), but neither TG2 mRNA nor protein expression was upregulated in the kidney. However, the relative amount of TG2 in the closed conformation was higher in DOCA mice. LDN-27219 did not affect albuminuria, but LDN-27219-treated DOCA mice showed less urine production and less collagen staining than vehicle-treated DOCA mice. LDN-27219 did not affect TG2 mRNA or TG2 protein expression or mRNA of fibrosis markers. LDN-27219-treated mice had enhanced vasorelaxation to the nitric oxide donor sodium nitroprusside. In conclusion, LDN-27219 treatment in the one-kidney DOCA–salt model did not affect renal TG2 mRNA and protein expression or albuminuria but still exerted beneficial effects in terms of reduced kidney fibrosis and urine production in addition to enhanced vasodilatation. Full article

Meat plays a key role in human nutrition, providing protein of high digestibility and essential micronutrients. However, according to the FAO and WHO, excessive consumption of red and processed meats may increase health risks due to their content of saturated fats, sodium, and E-number additives. For this reason, recent research has focused on the nutritional reformulation of meat products to develop functional and health-promoting alternatives that meet consumer expectations and respond to market trends for healthier and more sustainable foods. However, the addition or elimination of traditional ingredients in meat products leads to problems such as changes in texture, color, or sensory acceptability that must be solved. This review will focus on current reformulation strategies in the meat industry, including the reduction or replacement of animal fat with vegetable oils using technologies such as microencapsulation, or the elaboration of 3D gels using organogelants and hydrocolloids; the replacement of the umami flavor of salt with extracts from seafoods and mushrooms; the replacement of E-number additives with antioxidant and preservative extracts from plants and herbs; and the incorporation of dietary fiber through fruit peels and vegetable by-products. Full article

Multicolour graphene quantum dots (GQDs), from blue to orange emitting, were successfully synthesized via a one-step hydrothermal method using potassium hydrogen phthalate and o-phenylenediamine as the raw materials. After purification by silica gel column chromatography, four kinds of GQDs with maximum emission wavelengths of 420 nm (blue), 500 nm (green), 540 nm (yellow), and 555 nm (orange) were obtained, and all had a high quantum yield (9.7%, 8.8%, 9.3%, and 10.3%, respectively). The structural characterization revealed that the synthesized GQDs had a regular morphology, with a size of 2–3 nm and a thickness of 1–2 nm. The D-band-to-G-band ratio was less than 0.3, indicating that the GQDs had a high degree of graphitization. In addition, the emission peaks of the GQDs were red-shifted as the particle size increased, confirming that their luminescence was dominated by the quantum confinement effect. By analyzing the surface states and the functional groups of the multicolour GQDs, it was found that the GQDs had a similar elemental composition, which further proved that the emission wavelengths did not depend on the surface element composition, but conformed to the luminescence mechanism regulated by the quantum-limited effect. Furthermore, the four types of GQDs exhibited low cytotoxicity and good stability, suggesting their potential applications in biomarkers and for the synchronous detection of a variety of analytes. Full article

Red mud (RM) is a strongly alkaline waste residue produced during alumina production, and its high alkali and fine particle characteristics are prone to cause soil, water, and air pollution. Phosphogypsum (PG), as a by-product of the wet process phosphoric acid industry, poses a significant risk of fluorine leaching and threatens the ecological environment and human health due to its high fluorine content and strong acidic properties. In this study, RM-based cemented paste backfill (RCPB) based on the synergistic curing of PG and ordinary Portland cement (OPC) was proposed, aiming to achieve a synergistic enhancement of the material’s mechanical properties and fluorine fixation efficacy by optimizing the slurry concentration (63–69%). Experimental results demonstrated that increasing slurry concentration significantly improved unconfined compressive strength (UCS). The 67% concentration group achieved a UCS of 3.60 MPa after 28 days, while the 63%, 65%, and 69% groups reached 2.50 MPa, 3.20 MPa, and 3.40 MPa, respectively. Fluoride leaching concentrations for all groups were below the Class I groundwater standard (≤1.0 mg/L), with the 67% concentration exhibiting the lowest leaching value (0.6076 mg/L). The dual immobilization mechanism of fluoride ions was revealed by XRD, TGA, and SEM-EDS characterization: (1) Ca²⁺ and F⁻ to generate CaF₂ precipitation; (2) hydration products (C-S-H gel and calixarenes) immobilized F⁻ by physical adsorption and chemical bonding, where the alkaline component of the RM (Na₂O) further promotes the formation of sodium hexafluoroaluminate (Na₃AlF₆) precipitation. The system pH stabilized at 9.0 ± 0.3 after 28 days, mitigating alkalinity risks. High slurry concentrations (67–69%) reduced material porosity by 40–60%, enhancing mechanical performance. It was confirmed that the synergistic effect of RM and PG in the RCPB system could effectively neutralize the alkaline environment and optimize the hydration environment, and, at the same time, form CaF₂ as well as complexes encapsulating and adsorbing fluoride ions, thus significantly reducing the risk of fluorine migration. The aim is to improve the mechanical properties of materials and the fluorine-fixing efficiency by optimizing the slurry concentration (63–69%). The results provide a theoretical basis for the efficient resource utilization of PG and RM and open up a new way for the development of environmentally friendly building materials. Full article

This study aimed to develop a green and sustainable composite polysaccharide gel with antioxidant activity and freshness-monitoring properties. Blueberry pomace was repurposed to extract anthocyanins (BA), which were incorporated into chitosan (CS)/polyvinyl alcohol (PVA) and starch (S)/PVA matrices to prepare pH-indicating composite polysaccharide gels. The anthocyanin solution exhibited significant colorimetric responses to pH 2–14 buffer solutions. Comparative analyses revealed distinct performance characteristics: the CS/PVA-BA gel showed optimal elongation at break, low hydration (8.33 ± 0.57% water content), and potent antioxidant activity (DPPH: 73.59 ± 0.1%; ABTS: 77.47 ± 0.1%), whereas the S/PVA-BA gel demonstrated superior tensile strength and pH-responsive sensitivity. Structural characterization via FT-IR and SEM confirmed molecular compatibility between BA and polymeric matrices, with anthocyanins enhancing intermolecular hydrogen bonding. Applied to chilled beef (4 °C) freshness monitoring, the CS/PVA-BA gel exhibited color transformations from magenta-red (initial spoilage at 48 h: TVB-N > 15 mg/100 g, TVC > 4.0 lg CFU/g) to bluish-gray (advanced spoilage by day 6), correlating with proteolytic degradation metrics. These findings established a multifunctional platform for real-time food quality assessment through anthocyanin-mediated color changes in the composite gels, coupled with preservation activity, highlighting their significant potential as intelligent active packaging in the food industry. Full article

Three-dimensional (3D) food printing (3DFP) is an emerging technology that enables the creation of personalized and functional foods by precisely controlling nutritional content and shape. This study investigated the 3D printability and rheological behavior of cereal–legume starch-based gels formulated with germinated brown rice (GBR) and red adzuki bean (RAB) flours, supplemented with xanthan and guar gums as functional additives. The physicochemical and structural properties of the gels were characterized through FT-IR, rheology, texture analysis, SEM, and sensory evaluation. In addition, the 3D printing fidelity, rheological behavior, color attributes, textural properties, microstructure, and sensory scoring of the printed products were evaluated. The results indicated that the gels exhibited pseudoplastic behavior, with the RABF/GBRF ratio of 1:2 (RG1:2) formulation showing optimal color properties (ΔE* = 0.60 ± 0.86) and the RABF/GBRF ratio of 2:1 (RG2:1) formulation demonstrating superior printing fidelity and structural stability (printing accuracy = 99.37 ± 0.39%). The gels’ mechanical properties, such as hardness and chewiness, were significantly influenced by the RABF and GBRF ratios, with RG2:1 exhibiting the highest hardness (1066.74 ± 102.09) and RG1:2 showing the best springiness (0.64 ± 0.10). The sensory evaluation results indicated that the RABF/GBRF ratios of 1:1 (RG1:1) and RG1:2 had relatively high overall acceptance scores. These findings indicate that specific ratios of RABF and GBRF improve the 3D printability and textural properties of cereal–legume starch-based gels, enhancing their suitability for 3D food printing applications. This study provides valuable insights into the development of personalized and functional cereal–legume starch-based foods using 3DFP technology. Full article