Search Results (847)

Conventional antibiotic susceptibility testing (AST) primarily assesses planktonic bacteria. However, the three-dimensional architecture and barrier properties of biofilms mean that the minimum inhibitory concentration (MIC) for planktonic cells is typically far lower than the antibiotic exposure required for biofilm eradication. In this study, gelatin methacryloyl (GelMA) microspheres were used to create a three-dimensional biofilm microenvironment for the quantitative evaluation of biofilm tolerance. Escherichia coli K-12 MG1655 was immersed in GelMA microspheres and subjected to a series of antibiotic concentration gradients. Bacterial viability was inferred from time-dependent changes in microsphere diameter. The results demonstrated substantial tolerance of the resulting biofilms to ampicillin, ciprofloxacin, and ceftriaxone, with biofilm antibiotic tolerance values exceeding 200 μg/mL, 10–50 μg/mL, and 20–50 μg/mL, respectively. Relative to planktonic MICs, these tolerance levels are elevated by one to two orders of magnitude and surpass the standard clinical breakpoint thresholds. This methodology includes a high-throughput platform, involving only several hundred microspheres and achieving completion within 24 h, thereby offering a useful platform for investigating biofilm resistance mechanisms and guiding antibiotic treatment strategies. Full article

This review presents a focused assessment of the rapidly expanding field of gelatin-based eutectogels and identifies the gaps in current literature that justify this examination. Research on deep eutectic solvents (DESs and NADES) has advanced quickly, yet there is still no integrated view of how these solvent systems influence adhesion in gelatin-based gels. Eutectogels are soft materials formed by gelling DESs or NADES with biopolymers. Gelatin is widely used because it is biocompatible, biodegradable, and readily available. We provide a clear overview of the chemistry of DESs and NADES and describe how gelatin forms networks in these media. The review summarizes established knowledge on adhesion, highlighting the contributions of polymer network density, interfacial hydrogen bonding, and solvent mobility. New perspectives are introduced on how these factors interact to control adhesion strength, toughness, and reversibility. A key topic is the role of hydrogen bond donors (HBDs) and acceptors (HBAs). They define the hydrogen bonding environment of the solvent and represent an underexplored way to tune mechanical and adhesive behavior. Examples such as moisture-resistant adhesion and temperature-responsive bonding show why these systems offer unique and adjustable properties. The review concludes by outlining major challenges, including the lack of standardized adhesion tests and constraints in scalable production, and identifying directions for future work. Full article

Multifunctional hydrogels with an interpenetrated network structure have shown great potential for biomedical and tissue-regeneration applications. In this work, the biomedical hydrogel was fabricated with an interpenetrated network based on dopamine grafted gelatin (DA-Gel), and genipin crosslinked quaternary ammonium chitosan (QCS), incorporating epigallocatechin gallate (EGCG). The EDC/NHS and Schiff-base bond connections occurred in the hydrogels, as confirmed by Fourier-transform infrared (FT-IR) analysis. The properties of the fabricated hydrogels, including microstructure, degradation rate, adhesive strength, mechanical strength, and rheological behavior, can be regulated by adjusting the DA-Gel/QCS ratio or by using different crosslinking approaches. In addition, the fabricated hydrogels exhibited self-healing properties and strong adhesion to various materials and organs. Furthermore, the hydrogels performed good antibacterial activity against the typical bacteria, Escherichia coli and Staphylococcus aureus. EGCG encapsulated hydrogels displayed excellent antioxidant activities and good hemocompatibility. The hydrogels also demonstrated excellent cytocompatibility and good cell migration ability. The above results provide a facile approach to fabricate the biomedical hydrogels with a regulated network structure and multifunctional characteristics with potential in biomedical applications. Full article

The synthesis of sodium carboxymethylcellulose (NaCMC) from lignocellulosic pineapple stubble provides a renewable alternative to conventional cellulose sources for pharmaceutical applications. This study aimed to obtain NaCMC from pineapple biomass, characterize it according to pharmacopoeial specifications, and formulate hydrogels as a physicochemical proof-of-concept for future drug delivery and tissue regeneration applications. NaCMC was successfully synthesized and met the requirements of the Mexican Pharmacopoeia. Hydrogels were prepared by blending NaCMC with gelatin and crosslinking with citric acid. Spectroscopic, morphological, and thermal analyses confirmed the structural equivalence between pineapple-derived NaCMC (NaCMC-Pi) and commercial NaCMC (NaCMC-Co). Swelling and gel fraction studies showed that NaCMC-Pi hydrogels exhibited a higher gel fraction, indicating a more crosslinked network, which corresponded to lower swelling capacity but higher thermal stability compared to NaCMC-Co hydrogels. Overall, these results demonstrate that pineapple stubble is a viable source of pharmaceutical-grade NaCMC and that the resulting hydrogels provide a robust physicochemical basis for future biomedical validation. The use of agro-industrial residues additionally offers a complementary sustainability benefit without compromising pharmaceutical performance. Full article

The design of biomaterial scaffolds for bone tissue engineering requires a balance between bioactivity, porosity, mechanical stability, and osteoinductivity. Kappa- (KC) and iota-carrageenan (IC) have been explored for scaffold fabrication due to their biocompatibility and structural similarity to glycosaminoglycans. However, there are limited reports on how their distinct sulfation degree affects the osteogenic differentiation of cells cultured on them. While laponite has been reported as an osteoinductive nanoclay, its combined effect with different carrageenan types and its concentration-dependent effect on scaffold functionality remain unexplored. Therefore, we developed composite scaffolds comprising poly(vinyl alcohol) (PVA) and gelatin (GEL), reinforced with kappa- or iota-carrageenan (KC, IC) and functionalized with two different concentrations of laponite (LAP), 0.5 and 1% w/v, to monitor composition-structure-function relationships. The scaffolds were fabricated via lyophilization and dual crosslinking, and characterized for their physicochemical, structural, mechanical, and biological properties. The incorporation of both carrageenans into scaffolds, maintained high swelling ratios of 600% after 24 h, and increased porosity without altering their apparent density (0.09–0.11 g/cm³), whereas LAP preserved interconnectivity, densified pore walls, raised their compressive modulus at >220 kPa, and improved stability (>60% mass retained after 40 days). In vitro validation using MC3T3-E1 pre-osteoblastic cells demonstrated robust cytocompatibility, with the LAP-containing scaffolds significantly promoting cell adhesion, proliferation, and osteogenic differentiation, evidenced by elevated alkaline phosphatase activity, calcium production and collagen secretion. Direct comparison between KC and IC scaffolds confirmed that differences in sulfate substitution modulated scaffold stiffness, swelling, and degradation, while variation in LAP concentration affected the biological response, with the 0.5 wt% concentration favoring early cell proliferation, whereas the 1 wt% significantly promoted the osteogenic differentiation. This compositional strategy demonstrates how tuning the interplay between carrageenan and laponite can balance scaffold hydration, mechanical and biological properties, thereby guiding the design of scaffolds for bone repair. Full article

African catfish (Clarias gariepinus, AC) is one of the most widely farmed freshwater fish species in Central Europe. Processing operations generate up to 55% by-products (BPs), predominantly carcasses rich in proteins, lipids, and minerals. This study develops a comprehensive valorization process for ACBPs to recover gelatin, protein hydrolysate, fish oil, and pigments. The processing protocol consisted of sequential washing, oil extraction, demineralization, and biotechnological treatment to disrupt the collagen quaternary structure. A two-factor experimental design was employed to optimize the processing conditions. The factors included the extraction temperatures of the first (35–45 °C) and second fraction (50–60 °C). We hypothesized that enzymatic conditioning, combined with sequential hot-water extraction, would yield gelatin with properties comparable to those of mammalian- and fish-derived gelatins, while enabling a near-zero-waste process. The integrated process yielded 18.2 ± 1.2% fish oil, 9.8 ± 2.1% protein hydrolysate, 1.7 ± 0.7% pigment extract, and 25.3–37.8% gelatin. Optimal conditions (35 °C/60 °C) produced gelatin with gel strength of 168.8 ± 3.6 Bloom, dynamic viscosity of 2.48 ± 0.02 mPa·s, and yield of 34.76 ± 1.95%. Life cycle assessment (LCA) identified two primary environmental hotspots: water consumption and energy demand. This near-zero-waste biorefinery demonstrates the potential for comprehensive valorization of aquaculture BPs into multiple value-added bioproducts. Full article

Using raw milk in cheesemaking poses several risks and often requires higher salt levels. Gel brine is a promising brining method to reduce salt and to prevent excessive softening, yet it was not employed to raw milk cheese before. In this study, the impact of ripening in gel brine—prepared by adding selected thickeners (gelatin and carrageenan) to a 12% salt brine—on the composition, proteolysis, texture, and microbiological properties of raw milk cheese was examined over 120 days. The aim was to assess the potential of gel brine to shorten the ripening time of raw milk cheese at a relatively low salt concentration while maintaining acceptable quality parameters. Response surface methodology was used to determine the optimum ripening time and thickener concentrations required to achieve target microbial counts, proteolysis, and moisture levels. The addition of stabilizers did not significantly influence the overall composition of the cheese, except for salt in dry matter. Stabilizers also limited the increase in trichloroacetic acid-soluble nitrogen (TCA-SN) during storage and led to a marked reduction in Escherichia coli counts. Texture profile analysis results were significantly affected (p < 0.05). The optimum conditions were estimated as 0.9% carrageenan, 0.8% gelatin, and 35 days of ripening. Full article

Confectionery products, specifically jelly and gummy, require optimized structural, thermal, and nutritional properties for functionality and consumer acceptance. This study investigated the impact of furcellaran (FUR) and calcium L-threonate (Ca) on the physicochemical and the sensory properties of fish gelatin-based jelly (JFG). Furcellaran modestly enhanced gel strength and hardness, while its combination with calcium L-threonate produced synergistic improvements, with JFG-FUR-Ca achieving the highest gel strength (947.63 g) and hardness (78.14 N). Microstructural and intermolecular force analyses indicated that Ca²⁺ bridging between gelatin and furcellaran promoted ionic and hydrogen bonding, forming a dense and thermostable network. The combined incorporation of furcellaran and calcium L-threonate enhanced the rheological properties while preserving low syneresis. Sensory evaluation revealed minor reductions; however, overall acceptability was higher than 7. Calcium bioavailability after digestion through the gastrointestinal tract model remained high (70–80%), confirming effective calcium fortification. The synergistic incorporation of furcellaran and calcium L-threonate effectively improved the structural integrity, thermal stability, and calcium bioavailability of fish gelatin-based jelly, while maintaining acceptable sensory qualities, highlighting its potential as a functional calcium-fortified confectionery product. Full article

The alveolar epithelium plays a critical role in respiratory function, facilitating air exchange and serving as a barrier against inhaled pathogens. Its unique three-dimensional architecture, in which epithelial cells grow on spherical alveolar structures, significantly increases the surface area-to-volume ratio for efficient gas exchange but poses challenges for in vitro reconstruction. Here, we present a biomimetic alveolar model based on gelatin methacryloyl (GelMA) hydrogel microspheres with precisely controlled sizes and composition fabricated via microfluidic technology. These microspheres function as micro-scaffolds for cell adhesion and growth, and an oxygen-permeable honeycomb microwell array facilitates the rapid assembly of cell-laden microspheres into physiologically relevant alveolar-like structures. Using this model, the effects of toxic gas exposure and pathogen infection, and demonstrated its potential use for both basic physiological studies and pathological applications, was investigated. This system recapitulates key features of the alveolar microenvironment and offers a versatile platform for respiratory research and drug screening. Full article

Temperature-responsive hydrogels are sophisticated stimuli-responsive biomaterials that undergo rapid, reversible sol–gel phase transitions in response to subtle thermal stimuli, most notably around physiological temperature. This inherent thermosensitivity enables non-invasive, precise spatiotemporal control of material properties and bioactive payload release, rendering them highly promising for advanced biomedical applications. This review critically surveys recent advances in the design, synthesis, and translational potential of thermo-responsive hydrogels, emphasizing nanoscale and hybrid architectures optimized for superior tunability and biological performance. Foundational systems remain dominated by poly(N-isopropylacrylamide) (PNIPAAm), which exhibits a sharp lower critical solution temperature near 32 °C, alongside Pluronic/Poloxamer triblock copolymers and thermosensitive cellulose derivatives. Contemporary developments increasingly exploit biohybrid and nanocomposite strategies that incorporate natural polymers such as chitosan, gelatin, or hyaluronic acid with synthetic thermo-responsive segments, yielding materials with markedly enhanced mechanical robustness, biocompatibility, and physiologically relevant transition behavior. Cross-linking methodologies—encompassing covalent chemical approaches, dynamic physical interactions, and radiation-induced polymerization are rigorously assessed for their effects on network topology, swelling/deswelling kinetics, pore structure, and degradation characteristics. Prominent applications include on-demand drug and gene delivery, injectable in situ gelling systems, three-dimensional matrices for cell encapsulation and organoid culture, tissue engineering scaffolds, self-healing wound dressings, and responsive biosensing platforms. The integration of multi-stimuli orthogonality, nanotechnology, and artificial intelligence-guided materials discovery is anticipated to deliver fully programmable, patient-specific hydrogels, establishing them as pivotal enabling technologies in precision and regenerative medicine. Full article

This work investigates the modification of poly(lactic acid) (PLA) film properties for food packaging applications through the incorporation of modified gelatin (Gel-mod) and a choline chloride/glycerol deep eutectic solvent (DES). PLA/Gel-mod/DES materials were melt-processed and evaluated with respect to structure, morphology, thermal and mechanical behavior, processability, wettability, barrier performance, and compostability. Two incorporation routes were investigated for adding Gel-mod into the PLA matrix: direct incorporation and masterbatch preparation. FTIR and SEM analyses confirmed improved interfacial interactions and more homogeneous dispersion when Gel-mod was directly incorporated, compared with the masterbatch route. DES acted as an effective plasticizer and nucleating agent, reducing Tg, increasing crystallinity, and enhancing processability while maintaining thermal stability. Mechanical properties decreased relative to neat PLA, primarily due to increased crystallinity and chain scission. PLA_4Gel-mod demonstrated a more balanced performance, with higher elongation at break and improved processability than the other formulations, likely due to its single processing cycle, which minimized PLA degradation. Increased hydrophilicity led to higher water vapor transmission rates, correlating with accelerated biodegradation. Overall, the synergistic incorporation of DES and gelatin provides a viable strategy to tailor PLA properties, enabling the development of compostable packaging films suitable for sustainable food contact applications. Full article

Starch complexes have recently been identified as a new dietary supplement for dietary intervention in glycemic metabolism disorders. However, although the amylopectin significantly influenced starch complexes’ anti-digestibility, the underlying regulatory pattern remains unclear. Accordingly, this study constructed nano white waxy maize amylopectin (WMA) ternary complexes with a high self-assembly index (SI, 82.58%) using an ultrasound-assisted approach. And the relationship between self-assembly behavior and slow digestibility was revealed. Combined analyses of chemometrics revealed that during the WMA ternary self-assembly process, the increasing free side chains and α-1,6 glycosidic linkages contributed to the rise in potential, thereby generating more assembly sites and binding energy and ultimately elevating SI. Then, along with the transition from a diffuse state to V_h-type crystallinity and spherical configuration, increases in relative crystallinity, double helices, molecular weight, short-range order, and gel-network viscous were observed, whereas semicrystalline lamellar thickness and “blocklet” size decreased. These indicated that both the number and dimensions of hydrolysis channels were reduced. Consequently, the increasing gelatinization temperature led to rising slowly digestible starch content (19.86–43.28%), causing a more stable glycemic release after WMA ternary self-assembly. This investigation provides a key theoretical and technological foundation for the development of novel slow-digesting precision nutrition ingredients. Full article

Protein and starch are the two primary components of rice flour, significantly influencing their gelatinization and gel consistency. However, the role of protein in the gelatinization properties and gel consistency of high-starch starch remains unclear. Our study investigated the influence of protein on the gelatinization and gel consistency of high-amylose rice flour by analyzing six high-amylose rice varieties with differing protein levels. The results demonstrated that elevated protein content was associated with reduced breakdown (BD) and gel consistency. Additionally, a recombinant rice flour (RRF) system was developed by reintroducing extracted proteins into high-amylose rice flour in various ratios. The findings indicated that increasing protein proportions in the RRF system led to a marked decrease in gel consistency, accompanied by reductions in peak viscosity (PV), BD, final viscosity (FV), and setback (SB), while peak time (PeT) and pasting temperature (PaT) exhibited significant increases. Correlation analysis and microstructure observations support the hypothesis that proteins may enhance the stability of the paste by restricting the expansion of starch granules during gelatinization, which is related to the reduction in gel consistency. This study confirmed that protein content plays a significant role in determining the gel consistency of high-amylose rice, guiding the improvement of the quality of use or cultivating high-amylose rice suitable for processing. Full article

The study aimed to elucidate compositional changes in free phenolic compounds (fPHEs) during bakery processing of wheat flour supplemented with grape pomace (GP) and to assess dough rheology, bun shape and physical characteristics. Three GP variants were used—two from white cultivars (Rhine Riesling; Rhine Riesling + Muscat of Moravia) and one from a red blend (Saint Laurent and André)—at substitution levels of 5, 10, 20, and 30%. Thirty-four fPHEs were quantified by high-resolution UHPLC-MS-Orbitrap; dough rheology was assessed by Mixolab; and potential fPHE–wheat macromolecule interactions were examined via FTIR spectroscopy. Wheat flour contained only six fPHEs at low concentrations. Both white GP samples had similar profiles of 32 fPHEs, dominated by miquelianin (526–683 µg/g) and hyperoside + isoquercetin (390–476 µg/g). Red GP was highly enriched in anthocyanins (>30,000 µg/g) and generally exceeded white GP in most fPHEs. Even 5% GP substantially increased fPHE concentrations throughout processing. Several compounds (e.g., gallic acid, miquelianin) exceeded theoretical values, suggesting release from bound forms during fermentation and heating, whereas anthocyanins lost at least 30% during baking. Rheological analysis showed shorter dough development and reduced stability with increasing GP. White GP enhanced starch gelatinization (C3), gel stability (C4), and retrogradation, whereas 20% red GP markedly impaired gelatinization. GP additions ≥10% deteriorated bun shape and physical properties. FTIR confirmed spectral shifts likely due to fPHE–protein/starch interactions. In summary, incorporation of just 5% GP enhanced the nutritional profile of wheat buns. Full article

Durum wheat (Triticum durum) is one of the main raw materials in the food industry, used primarily in the production of pasta. During milling, semolina and flour are obtained with different size distributions, and different compositional and functional characteristics, which influence processes such as gelatinization, retrogradation and the final texture of the products. Understanding these changes is essential for optimizing the technological quality and shelf life of processed foods. The aim was to evaluate how particle size, composition, temperature, and treatment time affect gelatinization, retrogradation, and gel texture. Samples included common wheat flour (control), durum wheat semolina, durum wheat flour, and re-milled semolina (<180 μm). Hydrothermal tests were conducted at 95 °C with varying holding times, and at 140 °C with extended cooling to observe retrogradation. Composition and particle size were found to determine rheological behavior. Semolina showed higher retrogradation and produced firmer gels, while durum wheat flour, with higher protein and ash content, showed atypical profiles and less consistent gels. Increased temperature and time enhanced breakdown and reduced final viscosity, indicating starch thermal degradation. A correlation was observed between final viscosity and gel hardness. This study provides information useful for optimizing the milling, cooking, and development of durum wheat-based products with improved texture and shelf life. Full article