Search Results (479)

Aquaglyceroporins, including human AQP7, AQP10, and E. coli GlpF, are known to facilitate movements of glycerol, water, and some other uncharged molecules across the cell membrane. In this study we focused on the transport of water molecules in the absence of glycerol for AQP7, AQP10 and GlpF using the Transition State Theory for the novel application of permeability and kinetics studies. We conducted around 500 ns of in silico simulations of the aquaglyceroporins embedded in lipid bilayer membranes with intracellular-extracellular asymmetries in leaflet lipid compositions. For the water permeability analysis, we computed the transition rate constant with correction for recrossing events where the water molecules do not completely traverse the protein channel from one side of the membrane to the other side. We also studied the hydrogen bond distributions of the single-file waters and channel residues and linear water densities along the pores of the aquaglyceroporins. Interestingly, we found that there was an inverse correlation between the number of single-file water molecules in the channel and osmotic permeability. Full article

Bacterial-mediated infections represent a major risk factor for chronic wounds. Numerous polymeric dressings have been proposed to reduce this incidence and promote wound healing. In the present investigation, chitosan/collagen/honey-based sponges were prepared by freeze-drying. The effect of honey incorporation at different concentrations on the physicochemical and antibacterial properties of the sponges was evaluated. The SEM images showed that the surface and cross-sections of all samples had a porous structure. The pore size gradually increased in the range of 78.14 to 126.9 μm due to the increase in honey content in the sponges. This property resulted in considerably higher porosity degrees (79.90–90.13%) and absorption rates (ranges of 1357–1665% in deionized water and 865–1938% in PBS solution) in honey-loaded systems. Conversely, the honey composite formulations exhibited a reduction in permeability, with WVTR values ranging from 131.01 to 99.39 gh⁻¹m⁻² and values of WVP from 0.3255 to 0.2118 gm⁻¹d⁻¹mm Hg⁻¹. The mechanical properties showed that adding honey made the sponges more flexible (12.49–7.95% MPa) but decreased elongation rates in the sponges (16.36–7.56%) due to higher pore heterogeneity. The antibacterial tests indicated that all treatments had inhibitory effects against S. aureus, P. aeruginosa, E. coli, and L. monocytogenes. The results from cells viability assays and in vitro healing models using human keratinocytes demonstrate that chitosan/collagen/honey sponges represent a potential alternative for applications such as wound dressings to help treat skin ulcers. The physicochemical, antibacterial, and biocompatibility properties of chitosan/collagen/honey sponges indicated their potential as a promising alternative for clinical use. Full article

Background: The encapsulation of hydrophilic drugs within microparticles has gained significant interest in drug delivery systems due to their potential to improve stability, bioavailability, and controlled release of therapeutic agents. Biotin, a water-soluble vitamin, presents challenges such as rapid degradation and limited membrane permeability, which constrain its therapeutic effectiveness. Objectives: This study aims to develop and characterize biotin-loaded microparticles formulated with alginate, Eudragit^® E100, and CaCl₂, and to evaluate their characterization and potential applications. Methods: The microparticles were produced using the external ionic gelation method, where alginate and CaCl₂ solutions were mixed under probe sonication. Eudragit^® E100 was added as a complexing agent. The optimized formulation was used to encapsulate biotin, and various experimental variables were screened to study their influence on the properties of the microparticles. Results: Biotin was encapsulated in alginate microparticles (size: 634 nm; polydispersity index: 0.26; zeta potential: −45 mV) with an encapsulation efficiency of 90.5%. In vitro release studies using vertical diffusion Franz cells demonstrated a controlled release profile following the Weibull kinetic model. Conclusions: Encapsulation techniques offer a promising approach to overcome the limitations of hydrophilic drug delivery. The biotin-loaded microparticles developed in this study have potential applications in both topical and oral formulations, providing controlled release and improved therapeutic efficacy, and illustrate the broader applicability of polymeric encapsulation systems for improving the delivery of labile, hydrophilic bioactives. Full article

Background/Objectives: This study examined the effects of 2 weeks of betaine versus placebo supplementation (3 g/d) on 60 km cycling performance, gut permeability, and shifts in plasma metabolites. Methods: Participants included 21 male and female non-elite cyclists. A randomized, placebo-controlled, double-blind, crossover design was used with two 2-week supplementation periods and a 2-week washout period. Supplementation periods were followed by a 60 km cycling time trial. Six blood samples were collected before and after supplementation (overnight fasted state), and at 0 h, 1.5 h, 3 h, and 24 h post-exercise. Five-hour urine samples were collected pre-supplementation and post-60 km cycling after ingesting a sugar solution containing lactulose 5 g, ¹³C mannitol 100 mg, and ¹²C mannitol 1.9 g in 450 mL water. Other outcome measures included plasma intestinal fatty acid binding protein-1 (I-FABP), muscle damage biomarkers (serum creatine kinase, myoglobin), serum cortisol, complete blood cell counts, and shifts in plasma metabolites using untargeted metabolomics. Results: The time to complete the 60 km cycling bout differed significantly between the betaine and placebo trials (mean ± SE, 112.8 ± 2.3, 114.2 ± 2.6 min, respectively, (−1.41 ± 0.7 min) (effect size = 0.475, p = 0.042). No trial differences were found for I-FABP (interaction effect, p = 0.076), L:¹³CM (p = 0.559), the neutrophil/lymphocyte ratio (p = 0.171), serum cortisol (p = 0.982), serum myoglobin (p = 0.942), or serum creatine kinase (p = 0.694). Untargeted metabolomics showed that 214 metabolites exhibited significant trial treatment effects and 130 significant trial x time interaction effects. Betaine versus placebo supplementation was linked to significant increases in plasma betaine, dimethylglycine (DMG), sarcosine, methionine, S-adenosylhomocysteine (SAH), alpha-ketoglutaramate, and 5′methylthioadensone (MTA), and decreases in plasma carnitine and numerous acylcarnitines. Conclusions: Betaine supplementation modestly improved 60 km cycling performance but had no effect on gut permeability. The metabolomics data supported a strong influence of 2-week intake of betaine on the one-carbon metabolism pathway during the 24 h recovery period. Full article

Environmental pollution with microplastics (MPs) can have a negative impact on human health. Certain findings point to the relationship between MP and the development of inflammatory bowel diseases (IBD). We investigated the effect of MP consumption on the severity of chronic colitis in male C57BL/6 mice. The MP effect was modeled by drinking water consumption with a suspension of 5 μm PS particles at a concentration of 10 mg/L replacement for 12 weeks. Chronic colitis was induced by three seven-day cycles of 1% DSS consumption (starting from the 8th, 29th and 50th days of the experiment). We investigated inflammatory infiltration, the goblet cell volume fraction and the highly sulfated and neutral mucins content in them, the endocrine cell number, the ulcerative-inflammatory process prevalence, changes in the gene’s expression encoding tight junction proteins, glycocalyx components proapoptotic factor Bax and proliferation marker Mki67 in the colon, and TNFα, IL-1β, IL-6 and IL-10 cytokines content in the serum. In healthy mice, MP did not cause pathological changes in the colon; however, indirect data indicate an increase in colon permeability. In chronic colitis, MP leads to higher prevalence of all pathological changes in general, and ulcers in particular, in a greater number of crypt abscesses and enteroendocrine cells. MP consumption leads to a more severe chronic colitis course. Full article

This study introduces an innovative strategy for active, biodegradable food packaging through the incorporation of gamma-decalactone (GDL), a natural aromatic compound with antimicrobial properties, into apple-pectin-based edible films. The addition of GDL significantly modified the film structure, resulting in enhanced light barrier properties (the opacity increased from 1.10 to 8.64 a.u./mm), a more porous microstructure (confirmed by SEM), and reduced tensile strength (from 13.84 to 5.68 MPa). The films also exhibited lower water vapour sorption (from 1.45 to 0.80 g/g dry matter (d.m.) and increased gas permeability. FTIR analysis confirmed interactions between GDL and the polymer matrix. The films with GDL added exhibited antimicrobial properties against various microbial species, such as bacteria, yeasts, and moulds. A 5% addition of GDL to the coating completely inhibited the growth of Bacillus subtilis bacteria and Yarrowia lipolytica, reducing the number of yeast cells by 3 log units (after 48 h of culture, from 7.11 ± 0.09 to 4.09 ± 0.27 log CFU/mL) and limiting Monilinia fructicola mycelium growth by 70%. These results highlight GDL’s dual function as a natural aromatic and antimicrobial agent, supporting its potential application in sustainable packaging for perishable foods. Full article

This study aimed to investigate the efficacy of a composite coating composed of 150 mg/L ε-Poly-L-lysine (ε-PL) and 5 g/L chitosan (CTS) in extending the shelf life and maintaining the postharvest quality of fresh Tremella fuciformis. Freshly harvested T. fuciformis were treated by surface spraying, with distilled water serving as the control. The effects of the coating on storage quality, physicochemical properties, reactive oxygen species (ROS) metabolism, and membrane lipid metabolism were evaluated during storage at (25 ± 1) °C. The results showed that the ε-PL/CTS composite coating significantly retarded quality deterioration, as evidenced by reduced weight loss, maintained whiteness and color, and higher retention of soluble sugars, soluble solids, and soluble proteins. The coating also effectively limited water migration and loss. Mechanistically, the coated T. fuciformis exhibited enhanced antioxidant capacity, characterized by increased superoxide anion (O₂⁻) resistance capacity, higher activities of antioxidant enzymes (SOD, CAT, APX), and elevated levels of non-enzymatic antioxidants (AsA, GSH). This led to a significant reduction in malondialdehyde (MDA) accumulation, alongside improved DPPH radical scavenging activity and reducing power. Furthermore, the ε-PL/CTS coating preserved cell membrane integrity by inhibiting the activities of lipid-degrading enzymes (lipase, LOX, PLD), maintaining higher levels of key phospholipids (phosphatidylinositol and phosphatidylcholine), delaying phosphatidic acid accumulation, and consequently reducing cell membrane permeability. In conclusion, the ε-PL/CTS composite coating effectively extends the shelf life and maintains the quality of postharvest T. fuciformis by modulating ROS metabolism and preserving membrane lipid homeostasis. This study provides a theoretical basis and a practical approach for the quality control of fresh T. fuciformis. Full article

The demand for anion exchange membranes (AEMs) is growing due to their applications in water electrolysis, CO₂ reduction conversion and fuel cells, as well as water treatment, driven by the increasing energy demand and the need for a sustainable future. However, current AEMs still face challenges, such as insufficient permeability and stability in strongly acidic or alkaline media, which limit their durability and the sustainability of membrane fabrication. In this study, polyvinyl alcohol (PVA) and chitosan (CS) biopolymers are selected for membrane preparation. Zinc oxide (ZnO) and porous organic polymer (POP) nanoparticles are also introduced within the PVA-CS polymer blends to make mixed-matrix membranes (MMMs) with increased OH⁻ transport sites. The membranes are characterized based on typical properties for AEM applications, such as thickness, water uptake, KOH uptake, Cl⁻ and OH⁻ permeability and ion exchange capacity (IEC). The OH⁻ transport of the PVA-CS blend is increased by at least 94.2% compared with commercial membranes. The incorporation of non-porous ZnO and porous POP nanoparticles into the polymer blend does not compromise the OH⁻ transport properties. On the contrary, ZnO nanoparticles enhance the membrane’s water retention capacity, provide basic surface sites that facilitate hydroxide ion conduction and reinforce the mechanical and thermal stability. In parallel, POPs introduce a highly porous architecture that increases the internal surface area and promotes the formation of continuous hydrated pathways, essential to efficient OH⁻ mobility. Furthermore, the presence of POPs also contributes to reinforcing the mechanical integrity of the membrane. Thus, PVA-CS bio-based membranes are a promising alternative to conventional ion exchange membranes for various applications. Full article

To date, few studies have been published for cities in Germany that take into account climate change and changing hydrologic patterns due to increases in building density. This study investigates the efficiency of LID for past and future climate in the polycentric agglomeration area Frankfurt, Main (Central Germany) using observed and projected climate (model) data for a standard reference period (1961–1990) and a high emission scenario (RCP 8.5) as well as a climate protection scenario (RCP 2.6), under 40 to 75 percent building density. LID elements included green roofs, permeable pavement and bioretention cells. SWMM₅ was used as model for simulation purposes. A holistic evaluation of simulation results showed that effectiveness increases incrementally with LID implementation percentage and inverse to building density if implemented onto at least 50 percent of available impervious area. Building density had a higher adverse effect on LID efficiency than climate change. The results contribute to the understanding of localized effects of climate change and the implementation of adaption strategies to that end. The results of this study can be helpful for the scientific community regarding future investigations of LID implementation efficiency in dense residential areas and used by local governments to provide suggestions for urban water balance revaluation. Full article

Aloe vera gel is a valuable raw material used in the cosmetic industry for its skin care properties. The present study analyzed the effects of the fermentation of aloe vera gel with a tea fungus kombucha, which is a symbiotic consortium of bacteria and yeast, carried out for 10 and 20 days (samples F10 and F20, respectively). The resulting ferments and unfermented gel were subjected to chromatographic analysis to determine the content of biologically active compounds. The permeability and accumulation of these compounds in pig skin were evaluated. In addition, the methods of DPPH, ABTS and the determination of intracellular free radical levels in keratinocytes (HaCaT) and fibroblasts (HDF) cell lines were used to determine antioxidant potential. The results showed a higher content of phenolic acids and flavonoids and better antioxidant properties of the ferments, especially after 20 days of fermentation. Cytotoxicity tests against HaCaT and HDF cells confirmed the absence of toxic effects; moreover, samples at the concentrations tested (mainly 10 and 25 mg/mL) showed cytoprotective effects. The analysis of enzymatic activity (collagenase, elastase and hyaluronidase) by the ELISA technique showed higher levels of inhibition for F10 and F20. The kombucha ferments also exhibited better moisturizing properties and lower levels of transepidermal water loss (TEWL), confirming their cosmetic potential. Full article

This study investigates the capillary performance and wetting behavior of SLA (Stereolithography) 3D-printed porous structures, focusing on TPMS (triply periodic minimal surfaces)-Gyroid, Octet, Diamond, and Isotruss lattice designs. High-speed imaging was used to analyze droplet interactions, including penetration, spreading, and contact angles, with 16 μL water droplets dropping from 30 mm at 0.77 m/s. Results showed variable contact angles, with Isotruss and Octet having higher angles, while Diamond faced measurement challenges due to surface roughness. Numerical simulations of TPMS-Gyroid of 2 mm³ unit cells validated the experimental results, and Diamond, Octet, and Isotruss structures were simulated. Capillary performance was assessed through deionized (DI) water weight–time (w-t) measurements, identifying that the TPMS-Gyroid structure performed adequately. Structures with 4 mm³ unit cells had low capillary performance, excluding them from permeability testing, whereas smaller 2 mm³ structures demonstrated capillary effects but had printability and cleaning issues. Permeability results indicated that Octet performed best, followed by Isotruss, Diamond, and TPMS-Gyroid. Findings emphasize unit cell size, beam thickness, and droplet positioning as key factors in optimizing fluid dynamics for cooling, filtration, and fluid management. Full article

Wood is a green and renewable bio-based building material, but its hygroscopicity affects its dimensional stability, limiting its use in construction. Chemical modification can improve its properties, yet its effectiveness depends on wood permeability and traditional modifiers. This study first used a deep eutectic solvent (DES) to boost the permeability of North American alder wood. Then, methyl trimethoxysilane was impregnated under supercritical carbon dioxide (SCI), pressure (PI), vacuum (VI), and atmospheric pressure (AI) conditions. DES treatment damaged the cell structure, increasing wood permeability. Silane was deposited and polymerized in the cell lumen, chemically bonding with cell-wall components, filling walls and pits, and thickening walls. The VI group had the highest absolute density (0.59 g/cm³, +36.6%) and the lowest moisture absorption (4.4%, −33.3%). The AI group had the highest ASE (25%). The PI group showed the highest surface hardness (RL, 2592 N) and a water contact angle of 131.9°, much higher than natural wood. Overall, the VI group had the best performance. Silane reacts with cellulose, hemicellulose, and lignin in wood via hydrolysis and hydroxyl bonding, forming stable bonds that enhance the treated wood’s hydrophobicity, dimensional stability, and surface hardness. Full article

Background/Objectives: Thymol, one of the main compounds of thyme essential oil, has shown promising effects in treating various skin disorders owing to its anti-inflammatory, antimicrobial and antioxidative activities. Due to its limited solubility in water, thymol is commonly used in higher concentrations to achieve a suitable therapeutic effect, which can consequently lead to skin irritation. To overcome these limitations, we incorporated thymol into a vesicular phospholipid gel (VPG), a novel semisolid dermal vehicle consisting of highly concentrated dispersion of phospholipid vesicles (liposomes). Methods: Thymol was successfully loaded into two VPGs differing in bilayer fluidity, which were characterized for the physicochemical and rheological properties, storage stability, in vitro release, ex vivo skin permeability, in vitro compatibility with epidermal cells, wound healing potential, and antibacterial activity against skin-relevant bacterial strains. Results: High pressure homogenization method enabled preparation of VPG-liposomes of neutral surface charge in the size range 140–150 nm with polydispersity indexes below 0.5. Both types of VPGs exhibited viscoelastic solid-like structures appropriate for skin administration and ensured skin localization of thymol. Although both types of VPGs enabled prolonged release of thymol, the presence of cholesterol in the VPG increased the rigidity of the corresponding liposomes and further slowed down thymol release. Conclusions: Loading of thymol into VPGs significantly reduced its cytotoxicity toward human keratinocytes in vitro even at very high concentrations, compared to free thymol. Moreover, it facilitated in vitro wound healing activity, proving its potential as a vehicle for herbal-based medicines. However, the antibacterial activity of thymol against Staphylococcus aureus and methicillin-resistant S. aureus was hindered by VPGs, which represents a challenge in their development. Full article

Sediments are key players in the optimum functioning of ecosystems; however, they also represent the largest known repository of harmful contaminants. The vast variety of these sediment-associated contaminants may exert harmful effects on marine communities and can impair ecosystem functioning. Whole-cell biosensors are a rapid and biologically relevant tool for assessing environmental toxicity. Therefore, in this study, we developed a bioassay-based toxicity measurement system using genetically modified bacteria to create a whole-cell optical biosensor. Briefly, reporter bacteria were integrated and immobilized using a calcium alginate matrix on fiber-optic tips connected to a photon counter placed inside a light-proof, portable case. The calcium alginate matrix acts as a semi-permeable membrane that protects the reporter-encapsulated optical fiber tips and allows the inward passage of toxicant(s) to induce a dose-dependent response in the bioreporter. The samples were tested by directly submerging the fiber tip with immobilized bacteria into vials containing either water or suspended sediment samples, and the subsequent bioluminescent responses were acquired. In addition to bioavailable sediment toxicity assessments, conventional chemical methods, such as liquid chromatography–mass spectroscopy (LC-MS) and inductively coupled plasma optical emission spectroscopy (ICP-OES), were used for comprehensive evaluation. The results demonstrated the efficacy of the biosensor in detecting various toxicity levels corresponding to identified contaminants, highlighting its potential integration into environmental monitoring frameworks for enhanced sediment and water quality assessments. Despite its utility, this study notes the system’s operational challenges in field conditions, recommending future enhancements for improved portability and usability in remote locations. Full article

Investigating the contribution and interaction of water transport pathways in plant roots is important for understanding the functioning of the root hydraulic system. In this study, the real-time dynamics of lateral water transport along the cell-to-cell pathway and the diffusional water permeability of cells in the root suction zone of whole maize plants were investigated non-invasively by spin-echo NMR in response to rapid blockage of root apoplast. Apoplast blockage was carried out by insoluble precipitates using an original approach based on alternate incubation of whole plant roots in aqueous solutions of K₄[Fe(CN)₆] and CuSO₄. In the first stage after the apoplast blockage, the water transport along the cell-to-cell pathway and the diffusional water permeability of root cells was decreased 2.5 times. Using inhibitory analysis and gene expression analysis, it was shown that root aquaporins are involved in the decrease in cell-to-cell water transport in response to apoplast blockage. After an initial decrease, the cell-to-cell water transport was restored to initial values. At the same time, there was a partial compensation of the transpiration loss caused by the apoplast blockage. It is assumed that the apoplastic water flow in plant roots can modulate the cell-to-cell water transport and functional activity of aquaporins. Full article