Search Results (13,634)

Rice starch (RS) is widely consumed, but is usually rapidly digested, which may increase postprandial blood glucose levels. Therefore, regulating RS digestibility is important for development functional starch-based foods. In this study, sodium alginate (NaAlg) was incorporated into RS gels and subsequently crosslinked with Ca²⁺ to form a calcium alginate (CaAlg) network, and its effects on the physicochemical properties, digestion behavior, and physiological responses of RS gels were evaluated. Rheological measurement showed that the Ca²⁺-crosslinked alginate network increased the viscosity and viscoelastic moduli of RS gels. Low-field nuclear magnetic resonance analysis showed that the Ca²⁺-crosslinked alginate network reduced free water mobility. Structural characterization using Fourier-transform infrared spectroscopy, X-ray diffraction, and cold-field scanning electron microscopy shows that the Ca²⁺-crosslinked alginate network was associated with enhanced intermolecular interactions and a more continuous gel network, while all gelatinized samples exhibited predominantly amorphous structures. In vitro digestion experiments showed that the hydrolysis degree at 120 min decreased from 92.3% in RS to 85.6% in HCaAlg/RS. The rapidly digestible starch content significantly decreased from 72.4% to 68.4% (p < 0.05), while resistant starch significantly increased from 7.7% to 14.4% (p < 0.05). First-order kinetic fitting showed that C_∞ significantly decreased from 93.0% to 86.0%, and k significantly decreased from 0.027 to 0.013 min⁻¹ (p < 0.05). In vivo experiments showed that the Ca²⁺-crosslinked alginate/RS gels were associated with a lower postprandial glycemic response, with the incremental area under the curve significantly decreased from 747.2 to 591.7 mmol·min/L (p < 0.05), and the intestinal propulsion rate decreased from 89.6% to 75.3% (p < 0.05). These results suggest that Ca²⁺-crosslinked alginate network formation may modulate the structural properties, digestion behavior, and digestion-related physiological responses of RS gels, providing a basis for the development of starch-based functional foods with improved glycemic control. Full article

This study examined Kefiran, an exopolysaccharide derived from milk kefir grains, as a novel biopolymer for encapsulating phenolic extracts from sunflower cake and its antimicrobial properties in the development of natural and functional food ingredients. Kefiran was obtained from kefir grains using three extraction protocols: hot water (M1), hot water with 30% trichloroacetic acid (M2), and mild heat combined with ultrasound at 60 °C (M3). The ultrasound-assisted method produced the highest carbohydrate concentration. Spectrophotometric assays (phenol–sulfuric and Bradford), Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, and water-holding capacity were employed to characterize the composition, structure, and morphology of the extracts, revealing well-preserved polysaccharide fingerprints and a highly porous microstructure, consistent with their potential application in food systems. Kefiran was then evaluated as an encapsulating agent in complex coacervation at pH 3.75, using three Kefiran-based wall formulations (M1, M2, and M3) with gum arabic and whey protein isolate (WPI) as co-wall materials, and their performance was compared with gum arabic and WPI controls. Across formulations, coacervate microcapsules achieved high encapsulation efficiencies (83–93%), tunable particle sizes, and predominantly negative zeta potentials, indicative of good colloidal stability. The Kefiran extract and coacervate microcapsules demonstrated significant antioxidant and antimicrobial activity against Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans, with minimum inhibitory concentrations ranging from 250 to 1000 µg/mL. The findings support ultrasound-extracted Kefiran as a multifunctional biopolymer suitable for bioactive delivery and as a natural antimicrobial component in advanced functional food formulations. Full article

Hybrid conductive materials have attracted increasing attention due to their combined electrical conductivity, mechanical flexibility, and sustainability. In this work, new hybrid materials based on polyaniline (PANI)-wrapped multi-walled carbon nanotubes (MWCNTs) and microfibrous cellulosic substrates were developed and assessed for photocatalytic degradation of a model dye pollutant. First, in situ oxidative polymerization of aniline in formic acid (FA) was conducted in the presence of MWCNTs to afford stable dispersions of carboxylated polyaniline-wrapped carbon nanotubes (c-PANI/MWCNTs). Next, the dispersions were used for affordable impregnation of microfibrous cellulosic filter paper. The influence of the initiator type—potassium peroxodisulfate (KPS) and hydrogen peroxide—on polymer–nanotube interactions, stabilization and surface deposition was emphasized. The structural, surface, morphological and thermal properties of the obtained dispersions and cellulose nanocomposites were systematically investigated using Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy and thermal gravimetric analysis. The results revealed strong interfacial interactions between c-PANI and the pristine MWCNTs, resulting in improved dispersion stability and effective and even surface deposition of the conductive c-PANI/MWCNT hybrids into the cellulose fiber mesh. The photocatalytic degradation of 5 ppm methylene blue (MB) dye in the presence of the developed nanocomposite materials under UV-A illumination was studied. The results showed that the c-PANI@MWCNT-impregnated cellulose substrates exhibited enhanced photocatalytic ability (up to 83% degree of degradation of MB dye) in comparison with the pure c-PANI. Full article

Multilayer packaging—engineered by integrating complementary materials such as plastics, paper, and aluminum—has become a cornerstone technology for enhancing shelf life, minimizing spoilage, and reinforcing the mechanical integrity of packaging formats including films, pouches, and bottles. In this study, a laminate was developed by thermally bonding polylactic acid (PLA) with a poly(butylene adipate-co-terephthalate) (PBAT)/thermoplastic starch (TPS) matrix embedded with silver nanoparticles (Ag-NPs) at 0–3 wt.%. The resulting structures were systematically evaluated for their barrier performance, physicochemical characteristics, and antimicrobial functionality. Fourier-transform infrared (FTIR) spectroscopy confirmed the absence of chemical interactions between Ag-NPs and the polymer matrix, indicating physical dispersion rather than chemical bonding. However, at higher loading (3 wt.%), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX) revealed notable nanoparticle aggregation. Functionally, the multilayer films demonstrated markedly improved water vapor barrier properties compared to single-layer PBAT/TPS films. Migration studies showed that silver release increased with nanoparticle concentration and was significantly enhanced under acidic conditions relative to distilled water. Importantly, Ag-NP-incorporated laminates exhibited pronounced antibacterial activity against Staphylococcus aureus. Collectively, these findings highlight the potential of Ag-NP-enriched, starch-based multilayer laminates as next-generation active packaging systems that combine with effective microbial control. Full article

Hypogeous ascomycetous fungi (truffles) are challenging to study because they produce underground sporocarps that may not be encountered during traditional fungal surveys. Genea is one such genus that has garnered considerable attention over the past decades due to its role as an ectomycorrhizal partner and contribution to nutrient cycling and ecosystem stability. Yet, very limited information is available about its taxonomy, phylogeny and ecology worldwide. The current study aims to expand the known distribution of Genea species in Central Europe by integrating morphological, molecular and ecological analyses of new collections as well as the assessment of herbarium materials. Light microscopy and SEM were used to determine morphological characteristics along with FT-IR (Fourier transform infrared) spectroscopy measurements, which proved to be a powerful tool for species differentiation. Molecular phylogenetic analyses were conducted using the internal transcribed spacer (ITS1-5.8S-ITS2 = ITS) and D1/D2 domain of the large subunit (28S) of nuclear ribosomal DNA sequences to confirm species identity. In this study, a new species, Genea szemereiensis, along with the first report of Genea pinicola from Hungary, was made. In addition, the ecological parameters of the species, including habitat, altitude, soil nutrients and pH, were revised, which has not been reported previously in detail for this genus. Full article

The emergence of a novel crumb rubber (CR)/SBS-polymerized pellet has simplified the complex preparation process of composite-modified asphalt. However, the effectiveness of CR/SBS-polymerized pellets in improving asphalt performance has not been confirmed. This study mainly investigated the performance and reinforcement mechanism of polymerized pellet-modified asphalt. First, polymerized pellet-modified asphalt samples with different contents (10%, 20%, 30% and 40% of the asphalt mass) were prepared. Then, the physical properties, rheological behavior, thermal stability, and aging resistance of the pellet-modified asphalt samples were systematically evaluated, using both base asphalt and a commercially available styrene–butadiene–styrene triblock copolymer (SBS)-modified asphalt as control groups for comparison. Finally, the modification mechanism was explored through Fourier transform infrared spectroscopy (FTIR) and fluorescence microscopy (FM). The findings demonstrated that the incorporation of polymerized pellets could effectively decrease the penetration, elevate the softening point, and enhance the viscosity of asphalt. In addition, the high- and low-temperature performance, as well as the aging resistance of the modified asphalt, were significantly improved. These enhancing effects became more pronounced with increasing modifier content. The performance of SBS-modified asphalt is between 20% pellets MA and 30% pellets MA. The pyrolysis temperature range of all asphalt samples is 220 °C~500 °C, and infrared spectroscopy indicated that CR/SBS pellet-modified asphalt is mainly a physical mixing process. This work provides a scientific basis for further engineering applications of CR/SBS pellets. Full article

Ready-to-eat sea cucumbers (RSC) cannot be preserved at room temperature due to autolysis, which is closely related to the instability of collagen resulting from the disruption of hydrogen bonds. To investigate the protective effect of N-(3-Dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride/N-hydroxysuccinimide (EDC/NHS) cross-linking against disruption of hydrogen bonds and its role in stabilizing RSC quality at room temperature, this study designed comparative experiments involving EDC/NHS cross-linking treatments with varying sequences of hydrogen bonds disruption. The results indicated that EDC/NHS positively affects the stabilization of the collagen structure in RSC. The various quality parameters of both groups of RSC that underwent cross-linking treatment before and after hydrogen bonds disruption were significantly better than those of the control group, which only experienced the breaking of hydrogen bonds. Notably, the Eb group, which underwent EDC/NHS cross-linking treatment prior to the disruption of the hydrogen bonds network, yielded even more favorable results. Preliminary analyses of textural properties and moisture content suggested that EDC/NHS helps delay the deterioration of RSC quality. The levels of soluble components and carbonyl groups indicated that prior cross-linking treatment is more effective in mitigating collagen degradation and oxidation. Differential scanning calorimetry revealed that the reduction in ΔH for the Eb group was only 2.4%. Furthermore, fluorescence spectroscopy, Fourier transform infrared spectroscopy, and circular dichroism spectroscopy, examined from the perspectives of secondary and tertiary structures respectively, indicated that the cross-linking mechanism of EDC/NHS involves the formation of a more robust network of amide bonds, thereby preventing the disruption of hydrogen bonds and enhancing collagen stability, enabling it to better resist the cleavage of hydrogen bonds due to urea. The scanning electron microscope and Van Gieson’s staining techniques offer a clearer illustration of this point from a microscopic perspective. Moreover, molecular docking simulations have indicated the cross-linking mechanism of EDC/NHS at the atomic level, thereby establishing a scientific foundation for the potential application and development of EDC/NHS in room-temperature storage technologies for RSC. Full article

Multidrug-resistant bacterial pathogens pose a critical global health challenge, necessitating safe and effective antimicrobial alternatives. Plant-derived nanoparticles represent promising candidates due to their bioactivity and biocompatibility. Magnesium nitrate nanoparticles were synthesized using Momordica charantia peel extract through green chemistry. Phytochemical screening identified flavonoids, phenolics, tannins, and terpenoids that facilitated nanoparticle formation and stability. Characterization via scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy confirmed polydisperse size distribution (1–100 nm), crystalline structure, and functional group capping. Disc diffusion assays demonstrated concentration-dependent antibacterial activity against multidrug-resistant strains, with maximum inhibition zones of 17.6 ± 1.1 mm against Gram-positive bacteria. Minimum inhibitory concentration and minimum bactericidal concentration assays revealed high bactericidal activity, particularly against Gram-positive bacteria. Time-kill kinetic studies showed concentration- and time-dependent killing with ≥3 log₁₀ reduction in viable bacterial counts at higher concentrations. Nanoparticle–antibiotic combinations exhibited markedly enhanced activity against multidrug-resistant strains compared to free antibiotics, indicating synergistic effects. Toxicity assessment using Brine Shrimp Lethality Assay revealed low toxicity (LC₅₀ > 1000 µg/mL). Green-synthesized magnesium nitrate nanoparticles demonstrate potent antibacterial properties and effectively enhance antibiotic potency against multidrug-resistant bacteria. Further studies are required to validate therapeutic applicability. Full article

The sustainability, crop production, and food safety of agriculture are increasingly challenged by microplastic pollution, as agricultural soils are the largest reservoirs and may serve as points of contact for plastic particles in the food chain. This review provides a comprehensive overview of plant materials, fate and uptake pathways, detection techniques, and the possible risks of microplastics in agriculture. Agroecosystems are also a source of microplastics, such as plastic mulch films, sewage sludge, compost and manure additives, wastewater irrigation, polymer-coated fertilizers, greenhouse materials, atmospheric deposition, and decomposition of discarded agricultural plastics. Their distribution and mobility in soil are controlled by polymer composition, particle size, morphology, density, surface ageing, soil texture, organic matter content, tillage practices, runoff, leaching, and soil biota. Recent data show that microplastics, especially smaller microplastics and nanoplastics, can attach to root surfaces, penetrate plants via cracks in roots, areas of lateral root development, and apoplastic pathways, and eventually move to tissues aboveground. Plant tissue detection is often accomplished by digestion of the sample, density separation, visual and fluorescence microscopy, Fourier-transform infrared spectroscopy, Raman spectroscopy, pyrolysis–gas chromatography mass spectrometry, and electron microscopy, but standardization of these methods remains a significant challenge. Microplastics can disrupt seed germination, root structure, nutrient absorption, photosynthesis, oxidative homeostasis, biomass buildup, yield development, and quality. Further, their capacity to transport additives, plasticizers, heavy metals, and persistent organic pollutants raises concerns about the transfer of contaminants to edible plant parts and their potential transfer to human diets. Further studies are needed focusing on field-realistic exposure conditions, long-term crop–soil interactions, nanoplastics behaviour, standardised analysis procedures, uptake and translocation pathways, edible crop risk assessments, and sustainable mitigation approaches to reduce microplastics in agroecosystems. Full article

Aggregates comprise up to 95% of flexible pavement composition, critically influencing performance based on geological source and processing methods. In Pakistan, where approximately 264,175 km of roads carry 96% of inland freight, premium Margalla aggregates face increasing demand and depleting reserves, necessitating sustainable alternatives. This study comprehensively evaluates aggregates from five key quarries (Margalla, Malakand, Kohat, Swabi, and Besai) for highway suitability. Rigorous laboratory testing encompassed macro-level physical and mechanical properties and micro-characterization using Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), and Fourier Transform Infrared Spectroscopy (FTIR), alongside performance tests including Indirect Tensile Strength (ITS), rutting resistance, and fatigue analysis. Overall, Margalla aggregates exhibited the best performance, showing the lowest abrasion value (21%), highest Tensile Strength ratio (TSR) (82%), highest conditioned ITS (433.7 kPa), highest dynamic modulus (2120 MPa at 25 Hz), and the lowest rut depth (7.8 mm at 10,000 cycles). These superior properties are attributed to their favorable physical characteristics and high calcium content. Malakand and Kohat aggregates also demonstrated satisfactory performance, with TSR values of 79% and 76%, conditioned ITS values of 408.7 and 377.7 kPa, and rut depths of approximately 8.8 and 10.5 mm, respectively, indicating their suitability for medium-traffic pavements. In contrast, Swabi and Besai aggregates exhibited lower moisture resistance (TSR = 77% and 75%), lower conditioned ITS (355.7 and 337.7 kPa), and higher rut depths (~13.0 and 14.2 mm), making them less suitable for high-stress pavement layers. These findings support Malakand and Kohat aggregates as viable regional alternatives to Margalla. Full article

This study investigates the effects and mechanisms of three mineral admixtures—fly ash (FA), silica fume (SF), and metakaolin (MK)—on the fresh, mechanical, and microstructural properties of Yellow River sediment (YRS)-based shotcrete. A comprehensive experimental program was conducted, including setting time determination, workability assessment, and mechanical strength evaluation, complemented by microstructural characterization using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The results indicate that the incorporation of FA prolonged initial and final setting times and improved pumpability but reduced build-up thickness and compressive strength; splitting tensile strength at later ages remained comparable to the control. SF shortened the final setting time and reduced flowability but enhanced shootability, layer build-up, and medium- to later-age compressive and tensile strengths, with an optimal dosage of 5%. MK accelerated the final setting time, slightly reduced early-age compressive strength, but improved early-age splitting tensile strength and achieved 28-day compressive strength comparable to the control. Microstructural analyses revealed that FA participates in pozzolanic reactions forming C–(A)–S–H gel, while SF and MK promote the formation of dense C–S–H and carboalumination phases, enhancing matrix densification. Based on performance evaluation, the recommended dosages are FA ≤ 20%, SF ≤ 15%, and MK ≤ 15%. These results establish clear links between macroscopic performance and microstructural evolution, providing experimental guidance for the sustainable development of YRS-based shotcrete. Full article

In this study, polyvinyl alcohol (PVA) and chitosan (CS) were used as the base materials, and ethyl lauroyl arginate (LAE) as the antibacterial agent to prepare biodegradable bilayer composite films (P/C-L), whose properties compared with those of the monolayer films (P-C-L) of identical composition. Scanning electron microscopy (SEM) results revealed that the P/C-L films formed a compact microstructure with tight interlayer adhesion. Fourier transform infrared spectroscopy (FTIR) confirmed the presence of intermolecular hydrogen bonds within the P/C-L films without the formation of new chemical bonds, and X-ray diffraction (XRD) indicates that the crystallinity of the P/C-L films was dominated by that of PVA. P/C-L films exhibited a dual-surface structure with a hydrophobic CS layer and a hydrophilic PVA layer, broadening their potential application range. The P/C-L films demonstrated superior water resistance and light transmittance to the P-C-L films. When the LAE content increased from 0% to 10%, the P/C-L films displayed a more stable range of variation concerning visible light transmittance, water contact angle (CS layers), and moisture absorption than that of the P-C-L films, with the corresponding changing values being 86.86% to 62.09%, 96.79°to 72.46°, and 8.35% to 19.78%, respectively. Regarding antibacterial properties, the P/C-L films exhibited significantly enhanced activity across all LAE concentrations. Notably, P/C-L films at 2% LAE already outperformed P-C-L films at 4% LAE. At an LAE content of 10%, the inhibition zone diameters of the P/C-L films against E. coli and S. aureus reached 39.42 mm and 42.15 mm, which were 12.71 mm and 13.10 mm larger than those of the P-C-L films, corresponding to increases of 47.58% and 45.09%, respectively. In addition, both the P/C-L bilayer films and the P-C-L films could achieve complete biodegradation within 30 days under laboratory soil burial conditions. These findings suggest that P/C-L films show advantageous overall characteristics, highlighting their strong potential in the field of sustainable active food packaging. Full article

Banana (Musa acuminata), the second most cultivated fruit worldwide, generates approximately 220 tons of agricultural waste per hectare annually, with nearly 80% of the plant biomass remaining underutilised after harvest. Banana inflorescence, an underutilised by-product of banana cultivation, is commonly discarded despite its rich nutritional and bioactive composition, contributing to agricultural waste and environmental concerns. This study aimed to develop and evaluate banana inflorescence lozenges as a nutraceutical supplement while promoting sustainable agricultural waste valorisation. Freeze-dried banana inflorescence powder was incorporated into a hard lozenge formulation using the melt-and-mould method, and the formulation was optimised through physical evaluation. The optimised lozenges demonstrated acceptable mechanical properties, including friability of 0.13%, hardness of 55.16 kg/cm², and disintegration time of 35 min. Fourier-transform infrared spectroscopy with attenuated total reflectance (FTIR–ATR) confirmed the compatibility between the active ingredient and excipients. The formulated lozenges exhibited a total phenolic content of 22.74 ± 0.74 mg GAE/g DW and moderate antioxidant activity, with ABTS and DPPH IC₅₀ values of 30.65 mg/mL and 72.53 mg/mL, respectively. In vitro antidiabetic assays demonstrated α-glucosidase inhibition of 45.80% and α-amylase inhibition of 98.11%. Mineral analysis further revealed appreciable levels of potassium, magnesium, calcium, and iron. Although some reduction in bioactivity was observed following processing and formulation, banana inflorescence still demonstrated potential as a sustainable functional ingredient for nutraceutical applications and agricultural waste valorisation. Further studies involving stability assessment and in vivo validation are recommended. Full article

In this work, the catalytic effect of a mechanochemically synthesized Co–Fe metal–organic framework (Co–Fe-MOF) on the thermal decomposition behavior of composite ammonium perchlorate–aluminum (AP-Al) systems was studied. The structural and morphological properties of the synthesized catalyst were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The results confirmed the formation of a highly dispersed Co–Fe-MOF structure with a heterogeneous surface morphology and uniformly distributed active regions, as observed by SEM. The thermal decomposition behavior of the composites based on AP was studied using differential scanning calorimetry (DSC) at different heating rates. The addition of Co–Fe-MOF significantly affected the thermal decomposition process, moving the main exothermic decomposition step towards lower temperatures. At 5 wt.% of catalyst, the decomposition temperature decreased from 438–467 °C to 358–398 °C. The kinetic parameters were evaluated using the Kissinger and Ozawa–Flynn–Wall methods. The activation energy decreased from around 191–200 kJ·mol⁻¹ for pure AP and 184–194 kJ·mol⁻¹ for the AP-Al system to 95–109 kJ·mol⁻¹ after the introduction of 5 wt.% of Co-Fe-MOF. The observed catalytic activity is associated with accelerated electron transfer processes involving the redox couples Co³⁺/Co²⁺ and Fe³⁺/Fe²⁺, which favor the decomposition of AP and the oxidation of aluminum. The results demonstrate that the mechanochemically synthesized Co–Fe-MOF is an effective catalyst to improve the thermokinetic performance of AP-based energetic systems. Full article

Bamboo shoot dietary fiber (BSDF) is dominated by an insoluble fraction, which severely restricts its physicochemical performance and food application. In this study, the soluble dietary fiber (SDF) content of bamboo shoots was enhanced using three enzyme fermentation sequences: enzymatic hydrolysis followed by fermentation (EH), fermentation followed by enzymatic hydrolysis (F-EH), and integrated enzymatic hydrolysis and fermentation (IEHF). EH-F treatment resulted in the highest SDF content (17.27%). Variations in pH, biomass, enzyme activity, and short-chain fatty acids were assessed to understand the differences in the modification efficiency among the treatment sequences. Fourier transform infrared (FTIR) spectroscopy indicated that sequential enzymatic and fermentation treatments altered the chemical structure of bamboo shoot powder, consistent with the conversion of insoluble to soluble fractions. SDF from the EH-F treatment exhibited superior water-holding capacity (6.71 g/g), oil affinity (6.42 g/g), and DPPH radical scavenging rate (65.69% at 1.2 mg/mL). Moreover, SDF from the EH-F treatment achieved an 87.82% carbohydrate residue retention rate during simulated gastrointestinal digestion. These enhanced properties were associated with improved hydration properties resulting from the sequential tailoring process. This preliminary study explored the effects of different enzyme fermentation sequences on BSDF modification, providing a reference for the utilization of BSDF. Full article