Search Results (3,665)

The aim of the present paper is to study the antimicrobial effects of Nb₂O₅-containing nanosized powders. A combination of inorganic [telluric acid (H₆TeO₆)] and organic [Ti(IV) n-butoxide, Nb(V) ethoxide (C₁₀H₂₅NbO₅)] precursors was used to prepare gels. To allow for further hydrolysis, the gels were aged in air for a few days. The gels were amorphous, but at 600 °C the amorphous phase was absent, and only TiO₂ (anatase) crystals were detected. The average crystallite size of TiO₂ (anatase) was about 10 nm. The UV-Vis spectrum of the as-prepared gel showed red shifting in the cut-off region. The obtained nanopowders were evaluated for antimicrobial properties against E. coli ATCC 25922, P. aeruginosa ATCC 27853, S. aureus ATCC 25923, and C. albicans 18804. Among these, only E. coli was examined in combination with the antibiotic ciprofloxacin to assess whether there was a potential synergistic effect. The results showed that the material exhibited antibacterial activity against the abovementioned bacterial strains but not against C. albicans. In the case of E. coli combined with ciprofloxacin, a concentration-dependent enhancement in antibacterial activity was observed. The obtained samples can be considered as prospective materials for use as environmental catalysts. The newly synthesized nanocomposite showed a balancing, modulating, and neutralizing effect on the generation of ROS. The inhibitory effect was preserved in all tested model chemical systems at pH 7.4 (physiological), indicating potential biological applications in inflammatory and oxidation processes in vivo. Full article

Wood, as the oldest natural polymer composite material on Earth, holds significant importance in the era of carbon neutrality and serves as an irreplaceable core material in the furniture and construction industries. As a primary raw material for furniture, wood-based lignocellulosic boards have drawn increasing consumer attention due to their odor characteristics. In order to achieve the determination of odor compounds in lignocellulose-based panels, this study established a method combining dynamic headspace sampling (DHS), gas chromatography–mass spectrometry (GC–MS), and odor activity value (OAV) analysis. To address the wide concentration range of odor compounds in lignocellulose-based panels, a three-level standard curve was established to meet the detection of odor substances in common lignocellulose-based panels. The favorable conditions for each factor were as follows: sheet-shaped samples, TENAX-TA adsorbent, 20 mL headspace vials, and a split ratio of 25:1. The method demonstrated good linearity within the range of 0.002–15 mg/m³, with recovery rates ranging from 94.74% to 103.44%. The method was applied to analyze commercially available particleboard, fiberboard, and plywood. A total of 33 odor components were detected. The results indicated that aldehyde contributed significantly to the odor of particleboard, acids were the main contributors to the odor of fiberboard, and terpenes dominated the odor of plywood. The established method is suitable for the qualitative and quantitative analysis of odor compounds in lignocellulose-based panels and provides reliable technical support for tracing, identifying, and controlling odors in these materials. Full article

Juglans neotropica Diels, classified as endangered on the IUCN Red List, plays a crucial role in the resilience of Andean montane forests in southern Ecuador—a megadiverse region encompassing coastal, Andean, and Amazonian ecosystems. This study examines how climatic, edaphic, and topographic gradients influence the species’ phenotypic traits across six source localities—Tibio, Merced, Tundo, Victoria, Zañe, and Argelia—all of which are localities situated in the provinces of Loja and Zamora Chinchipe. By integrating long-term climate records, slope mapping, and soil characterization, we assessed the effects of temperature, precipitation, humidity, soil moisture, and terrain steepness on leaf presence, fruit maturation, and tree architecture. Over the past 20 years, temperature increased by 1.5 °C (p < 0.01), while precipitation decreased by 22%, disrupting local edaphoclimatic balances. More than 2000 individuals were measured in forest stands, with estimated ages ranging from 11 to 355 years. ANOVA results revealed that Tundo and Victoria exhibited significantly greater DBH, height, and volume (p ≤ 0.05), with Victoria showing a 30% larger DBH than Argelia, the lowest-performing provenance. Soils ranged from loam to sandy loam, with slopes exceeding 45% and pH levels from slightly acidic to neutral. These findings confirm the species’ pronounced phenotypic plasticity and ecological adaptability, directly informing site-specific conservation strategies and long-term forest management under shifting climatic conditions. Full article

This study investigates the scavenger activity of Polynucleotide High Purification Technology (PN HPT^TM), alone or in combination with hyaluronic acid (PN HPTTM + HA) against oxidative stress induced by hydrogen peroxide (H₂O₂). Since oxidative stress is implicated in numerous pathological conditions, identifying effective antioxidants is crucial for therapeutic development. We employed a cell-free fluorometric assay based on Calcein-AM, a fluorescence probe whose signal increases proportionally to the generation of reactive oxygen species (ROS), to evaluate the ability to neutralize ROS under varying oxidative stress conditions and determine the dose- and time-dependent effects of these compounds. PN HPT^TM, HA, and PN HPTTM + HA were tested at various concentrations over multiple time points. Our results demonstrated that all tested treatments significantly lowered ROS levels compared to the untreated control. Notably, the PN HPT^TM -based compounds exhibited robust scavenging activity, with PN HPTTM + HA displaying the strongest and most consistent ROS-neutralizing effect across all concentrations and time points. This enhanced performance suggests a synergistic interaction between PN HPT^TM and HA, potentially due to complementary mechanisms of free radical scavenging and structural stabilization. These findings highlight the potential of PN HPT^TM and PN HPTTM + HA as effective antioxidative agents, offering potential for therapeutic applications where oxidative stress is central, including wound healing and tissue regeneration. Full article

Lipid droplets are the neutral lipid storage compartments of eukaryotic cells. Mitochondria are the main source for ATP, which is generated through oxidative phosphorylation. Thus, both organelles play essential roles in fatty acid metabolism and energy homeostasis. Therefore, functional and physical interaction of lipid droplets with mitochondria is of special importance as essential processes, such as lipolysis, triacylglycerol synthesis, thermogenesis or the protection against oxidative stress, and lipotoxicity, depend on cooperation of these two organelles. Physical interaction of LDs with mitochondria is mediated by specific molecular complexes at inter-organelle membrane contact sites. Substantial progress has been achieved during the last decade in understanding the formation and the structural components of lipid droplet–mitochondria contact sites. This review gives a brief overview of the different molecular complexes that have been identified in different mammalian cell types under different conditions and their regulation. Full article

Polymer-bonded Nd–Fe–B and Sm–Fe–N magnets have excellent magnetic properties, but their corrosion resistance is inferior. Polymer-bonded magnets, the binary alloys Nd–Fe and Sm–Fe, and the metals Fe, Nd, and Sm were investigated in electrolytes with a pH range of 1.8 to 12.8. Potentiodynamic polarisation measurements showed that these materials corrode in acidic (H₂SO₄) and near-neutral (Na₂SO₄ and NaCl) electrolytes. Iron passivates at pH > 9, but Nd and Sm passivate only in strongly alkaline electrolytes (pH > 12). The alloys and magnets combine the characteristics of the individual metals. Scanning electron microscopy with energy-dispersive X-ray spectroscopy characterised the surface layers before and after electrochemical measurements. The speciation and the depth distribution of elements in the surface layers were analysed using X-ray photoelectron spectroscopy. In the H₂SO₄, a non-protective layer was formed. In NaCl, the corrosion products were more abundant, consisting of a mixture of oxides, hydroxides, and chlorides, while in NaOH, an oxide/hydroxide layer was formed. The corrosion product layers formed in the H₂SO₄ and NaCl electrolytes were significantly thicker for the Sm–Fe–N magnet than for the Nd–Fe–B magnet. Understanding the differences and similarities in the electrochemical behaviour of magnets in various electrolytes is essential to overcoming corrosion-related problems. Full article

The low efficiency of the microbial gasification of coal limits the application of bio-coal bed methane technology. The co-fermentation of coal and biomass provides a new approach for improving the degradation rate of coal. In this study, a co-fermentation system comprising five different coal orders with five microalgae was constructed in the laboratory, and the methanogenic characteristics of coal–algae co-fermentation and its microbiological mechanism were systematically investigated in terms of gas production, soluble organic matter, and microbial community characteristics. The results showed that the combination of lignite and Nannochloropsis exhibited optimal methane production, with a methane yield of 26.43 mL/g coal. Biogenic methane yields for lignite–Porphyra and anthracite–Porphyra were 23.43 mL and 21.28 mL, respectively, demonstrating the potential for algae to enhance gas production even in high-rank coals. pH monitoring revealed that algal species played a critical role in the acidification process. Dunaliella caused a continuous pH decrease, reaching 3.76 by day 30, while Nannochloropsis maintained a neutral pH of 6.95, optimizing the fermentation environment. Significant differences in soluble organic matter were observed between the lignite and anthracite fermentation systems, with lignite systems producing more volatile fatty acids, including acetic and butyric acids. Microbial community analysis revealed that Methanosarcina, an acetic acid-utilizing methanogen, was dominant in lignite and anthracite systems, while Syntrophomonas played a key role in lignite–Nannochloropsis co-fermentation. These findings provide valuable insights into optimizing coal microbial gasification and selecting appropriate algal species to enhance methane production efficiency. Full article

Free radicals are molecules generated during some biochemical processes, and in excess, they can cause various diseases; therefore, their production needs to be controlled in humans. One approach to achieving this is through the consumption of substances with antioxidant capacity, which are capable of neutralizing free radicals. This study evaluated the antioxidant activity of cellooligosaccharides (COS) and xylooligosaccharides (XOS) solutions, extracted from banana leaf and pseudostem, and guava seed cake, unfiltered and filtered using a Sep-pak filter. Additionally, the antioxidant activity of their monomers, including commercial glucose, xylose, and cellobiose, was evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical assay. Antioxidant activity was observed in the unfiltered COS and XOS solutions, with maximum DPPH radical reduction of 48.3% and 84.2%, respectively. In filtered COS and XOS solutions, the reduction did not exceed 0.5%. It can be concluded that the antioxidant activity is due to the presence of compounds dissolved in the oligosaccharide solutions, such as lignin, extractives and carboxylic acids, which were qualified by the Folin–Ciocalteu method, nuclear magnetic resonance, and scanning spectrophotometry. Full article

Thermogravimetric analysis (TGA) has been extensively applied in polymeric characterization and quality inspection, facilitating in-depth investigations of the microstructural thermal response characteristics of polymers, including thermal stability, composition analysis, and thermal decomposition mechanisms. Here, the impacts of six factors on the TG thermal analysis curves obtained during operation are systematically examined while analyzing their causes and recommending solutions. Furthermore, the thermal degradation kinetics of an ionomer formed by neutralizing an ethylene–methacrylic acid copolymer with metal ions (SGP membrane) used in laminated tempered glass is analyzed using the Arrhenius equation, Ozawa–Flynn–Wall hypothesis and Kissinger method. Kinetic parameters at 5% degradation are fitted and used to predict the service lifetime of the SGP membrane. The results indicate that the SGP membrane sample exhibits activation energy Ea = 136.90 kJ/mol, reaction order n = 1.65 and pre-factor A = e^25.93. It can be seen that the service lifetime of the SGP membrane sample is 16 years at 80 °C and 1.65 years at 100 °C. Full article

This study compared the effects of two C3 forages (Italian ryegrass [RG], Timothy grass [TG]) and two C4 forages (Klein grass [KG], Bermuda grass [BG]) on growth performance, nutrient digestibility, and nitrogen (N) balance in Korean crossbred black goats to evaluate C4 warm-season forages as alternatives under changing climate conditions. Sixteen castrated goats (10 months old) were allocated to four treatments using a randomized complete block design. Diets contained 40% treatment-specific forage and 60% commercial concentrate. After adaptation periods, a 5-day metabolism trial measured performance and digestibility parameters. No significant differences occurred among treatments for growth performance or digestibility of dry matter, crude protein, neutral detergent fiber, ash, and non-fiber carbohydrate. C4 grasses showed significantly lower acid detergent fiber and ether extract digestibility than C3 grasses, with KG having the lowest ether extract digestibility. The KG group had higher N intake and absorption than the TG group, while BG showed lower urinary and total N excretion than KG. No differences existed in retained N, utilization efficiency, or biological value among groups. Both C3 and C4 forages supported comparable goat growth performance, providing a reference for utilizing different photosynthetic pathway forages under changing climatic conditions. Full article

The effective and rapid separation of oil–water emulsions at room temperature, particularly under harsh environmental conditions like acid–base fluctuations, high salinity, and the coexistence of surfactants, remains a significant challenge in oily wastewater treatment. To address this, a novel amphiphilic demulsifier, MOF-74@SiO₂-GPTMS grafted ANP (MSG-ANP), was synthesized by first modifying MOF-74@SiO₂ (MS) with γ-glycidoxypropyltrimethoxysilane (GPTMS) to create epoxy-functionalized MSG particles, followed by grafting the non-ionic polyether C₁₂–C₁₄ aliphatic polyethylene oxide polyoxypropylene (ANP) onto MSG. Bottle tests demonstrated that MSG-ANP achieved a high demulsification efficiency of 93% within 15 min for oil-in-water emulsions at room temperature. It exhibited excellent environmental tolerance, maintaining efficiencies of 89% at pH 3.0, 82% at pH 11.0, and 95% under high salinity (50,000 mg/L, pH 6.8). Furthermore, MSG-ANP effectively treated surfactant-stabilized emulsions, exceeding 96% efficiency against both cetyltrimethylammonium bromide and sodium dodecyl sulfate after 30 min, outperforming commercial demulsifiers SP-169 and AR-331 by factors of 1.2 and 1.6, respectively. This superior performance stems from synergistic hydrogen bonding (via hydroxyl, ether, ester, Fe-O, and Si-O groups) destabilizing the interfacial film and electrostatic neutralization of coalescing charged droplets. Consequently, MSG-ANP presents a promising solution for rapid, room-temperature demulsification across a wide pH range and under high-salinity conditions. Full article

The leather industry produces a substantial amount of solid waste, which is frequently disposed of via incineration or landfilling. While hydrolysis offers a valuable and sustainable method to chemically recycle leather waste, both acidic and alkaline processes present challenges due to the salts produced during neutralization. This study aims to upcycle leather scraps through hydrolysis, producing a powdered filler for versatile composites suitable for both LCD vat photopolymerization and Direct Ink Writing 3D printing technologies. A zero-waste hydrolysis process was adopted using sulfuric acid neutralized with calcium hydroxide, achieving a yield of 91.3%. The composites featured a matrix composed of polyethylene-glycol-diacrylate and glycerol dimethacrylate, with embedded leather hydrolysate powder at concentrations up to 20% w/w_matrix. Tensile tests conducted on neat resin and composites demonstrated the strengthening effect of leather hydrolysate filler. Additionally, rheological tests displayed a viscoelastic behavior suitable for the adopted 3D printing technologies. The composites were successfully 3D-printed using both Direct Ink Writing and vat photopolymerization techniques, showing promising printing accuracy. This work demonstrates the potential of valorizing leather waste, upcycled via a hydrolysis method, to produce composites suitable for additive manufacturing to advance the sustainability and the circularity of the fashion sector. Full article

The comparison of rice albumin (RA) after heat treatment at neutral and acidic conditions was investigated in this study. Compared to the decreased thioflavin T (ThT) intensity of RA at pH 2 during heating, the ThT intensity of RA at pH 7 increased throughout the process of fibrillization. After fibrillization, the ThT intensity of RA at pH 7 was significantly increased by 27%, 38% and 35% at the protein concentrations of 1%, 2% and 4%, respectively. In addition, worm-like fibrils with a contour length of 100–300 nm were formed after heating at neutral conditions, accompanied by an increased average particle size and structural re-arrangement. Furthermore, the fibril formation at pH 7 involved the enhancement of an ordered β-sheet structure. However, only spherical agglomerate with a larger average particle size (>2000 nm) was observed when RA was heated at pH 2, because excessive hydrolysis destroyed the fibril-core sequences of RA. Additionally, the low solubility and high hydrophobicity of RA at pH 2 were not conducive to the formation of fibrils. In a word, a neutral environment is suitable for RA-based fibril formation, which provides a new insight for its future uses in food products. Full article

Current acne therapies face major limitations, including antibiotic resistance and skin irritancy. In this study, a synergistic strategy combining cryptotanshinone and madecassoside was developed through functional complementarity. Antibacterial activity against Cutibacterium acnes was evaluated using minimum inhibitory concentration (MIC) and inhibition zone assays, while cytotoxicity was assessed using human keratinocytes (HaCaTs). Anti-inflammatory efficacy was quantified by measuring tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), interleukin-6 (IL-6), and prostaglandin E₂ (PGE₂) in lipopolysaccharide-stimulated macrophages and a copper sulfate-induced zebrafish inflammatory model. Systemic safety was examined in zebrafish models (developmental toxicity and sodium dodecyl sulfate-induced irritation). Finally, macroscopic severity, histopathology, and serum cytokines were used to assess an oleic acid-induced rat acne model. Cryptotanshinone inhibited Cutibacterium acnes (minimum inhibitory concentration = 62.5 μg/mL) but exhibited cytotoxicity (>5 μg/mL) and irritancy (≥1000 μg/mL). Madecassoside eliminated cryptotanshinone-induced cytotoxicity and reduced irritation. Importantly, the combination maintained antibacterial efficacy while synergistically enhancing anti-inflammatory effects, achieving a 94% reduction in follicular hyperkeratosis compared with 39% for cryptotanshinone alone (p < 0.01), alongside normalization of histopathology and cytokine levels. In conclusion, madecassoside functionally complements cryptotanshinone by neutralizing its cytotoxicity and irritancy, enabling a safe, synergistic therapy that concurrently targets antibacterial and anti-inflammatory pathways in acne pathogenesis. Full article

Many industries release untreated synthetic dye effluents into water bodies, harming ecosystems and human health. Therefore, an economical and sustainable solution for treating dye-contaminated water must be developed. In this study, mulberry leaves (Morus nigra L.), as a cost-effective and sustainable adsorbent, were prepared to remove Basic Yellow 28 (BY28) and Basic Blue 3 (BB3) cationic dyes from industrial dye wastewater using adsorption. Batch experiments with key variables such as initial dye concentration, adsorbent dosage, contact time, temperature, stirring speed, and pH were conducted to find optimal conditions. The effectiveness of mulberry leaves as an adsorbent after multiple regeneration cycles was examined. The adsorbent was characterized through various instrumental methods, including FTIR, SEM, XRD, and BET analysis. Adsorption performance was analyzed using the Langmuir and Freundlich isotherm models. The results showed that the mulberry leaf adsorbent best fits the Langmuir model, with R² values of 0.999 for BY28 and 0.973 for BB3. The maximum adsorption capacities were 0.15 mg/g for BY28 and 7.19 mg/g for BB3, indicating their upper limits for dye uptake. The optimal conditions achieving removal efficiencies of over 99% were 1.5 g, 50 mL, 15 min, 180 rpm, and 10 mg/L at 30 °C for BY28 in neutral pH (7) and 1.5 g, 50 mL, 45 min, 100 rpm, and 30 mg/L at 40 °C for BB3 in basic pH (10). The regeneration of mulberry leaves as an adsorbent through acid treatment with 0.1 M HCl and 0.1 M CH₃COOH solutions maintained a high performance, achieving up to 98% dye removal efficiency after two regeneration cycles. It has been observed that successful results can be achieved in terms of reusability. Additionally, the removals of BB3 and BY28 performed in an ultrasonic-bath-assisted environment successfully achieved removal efficiencies of 84.87% and 75.41%, respectively. According to the results, mulberry leaves can effectively be used in wastewater treatment to remove dyes, can be reused multiple times, and thus serve as an environmentally friendly and sustainable adsorbent. Full article