Search Results (1,021)

1,3-butadiene (BD) is a volatile organic pollutant. Upon inhalation, it is metabolically activated to reactive epoxides which alkylate genomic DNA and form potentially mutagenic monoadducts and DNA–DNA crosslinks including N7-(1-hydroxyl-3-buten-1-yl)guanine (EB-GII) and 1,4-bis-(guan-7-yl)-2,3-butanediol (bis-N7G-BD). While metabolic activation resulting in mutagenicity is a well-established mode of action for 1,3-butadiene, characterization of the extent of inter-individual variability in response to BD exposure is a gap in our knowledge. Previous studies showed that population-wide mouse models can be used to evaluate variability in 1,3-butadiene DNA adducts; therefore, we hypothesized that this approach can be used to also study variability in the formation and loss of BD DNA adducts across tissues and between sexes. To test this hypothesis, female and male mice from five genetically diverse Collaborative Cross (CC) strains were exposed to filtered air or 1,3-butadiene (600 ppm, 6 h/day, 5 days/week for 2 weeks) by inhalation. Some animals were kept for two additional weeks after exposure to study DNA adduct persistence. EB-GII and bis-N7G-BD adducts were quantified in liver, lungs and kidney using established isotope dilution ESI-MS/MS methods. We observed strain- and sex-specific effects on both the accumulation and loss of both DNA adducts, indicating that both factors play important roles in the mutagenicity of 1,3-butadiene. In addition, we quantified the intra-species variability for each adduct and found that for most tissues/adducts, variability values across strains were modest compared to default uncertainty factors. Full article

The potential of elastomeric composites reinforced with natural fillers to replace traditional synthetic materials in applications involving exposure to acidic environments offers both economic and environmental advantages. On the one hand, these materials contribute to cost reduction and the valorization of organic waste through the development of value-added products. On the other hand, the presence of wood waste in the composite structure enhances biodegradation potential, making these materials less polluting and more consistent with the principles of the circular economy. The present study aims to evaluate the behavior of composites based on Ethylene Propylene Diene Monomer (EPDM) synthetic rubber, reinforced with silica and wood sawdust, in a weakly acidic yet strongly corrosive environment—specifically, acetic acid solutions with concentrations ranging from 10% to 30%. The study also investigates the extent to which varying the proportions of the two fillers affects the resistance of these materials under such environmental conditions. Physico-chemical, structural, and morphological analyses revealed that the materials underwent chemical modifications, such as acetylation of hydroxyl groups. This process reduced the hydrophilic character of the sawdust and, combined with the formation of stable interfaces between the elastomeric matrix and the fillers during vulcanization, limited acid penetration into the composite structure. The composites in which 20 phr or 30 phr of wood sawdust were used-replacing equivalent amounts of silica from the initial 50 phr formulation-demonstrated the highest resistance to the corrosive environments. After 14 days of exposure to a 20% acetic acid solution, the composite containing 30% wood sawdust exhibited a decrease in cross-link density of only 1.44%, accompanied by a reduction in Young’s modulus of just 0.95%. At the same time, tensile strength and specific elongation increased by 22.57% and 26.02%, respectively. FTIR and SEM analysis confirmed good rubber–filler interactions and the stability of the composite structure under acidic conditions. Full article

The present work is aimed at shedding light on the evolution of surface chemistry of a commercial activated carbon (AC) support during the preparation of supported metal oxide (MO) catalysts by the conventional wet impregnation method. Particular attention is paid to the chemical changes of oxygen-containing surface functionalities across three preparation stages of impregnation, oven-drying, and thermal treatment. AC was impregnated with aqueous solutions of several MO precursors (Al(NO₃)₃, Fe(NO₃)₃, Zn(NO₃)₂, SnCl₂, and Na₂WO₄) at 80 °C for 5 h, oven-dried at 120 °C for 24 h, and heat-treated at 200 °C and 850 °C for 2 h under an inert atmosphere. The surface chemistry of the resulting catalyst samples, classified in three series by the thermal treatment, was mainly studied by FT-IR spectroscopy, complemented by elemental analysis and pH of the point of zero charge (pH_pzc) measurements. During impregnation, phenolic hydroxyl and carboxylic acid groups were predominantly formed by wet oxidation of chromene, 2-pyrone, and ether-type structures found in the pristine AC. The extent of these oxidations correlated with the oxidising power of the precursor solutions. As expected, thermal treatment at 850 °C brought about markedly stronger chemical changes, with most of the above oxygen functionalities decomposing and forming less acidic structures, such as 4-pyrone groups, metal carboxylates, and C-O-M atomic groupings. All these surface chemical modifications result in a lowering of the strong basicity of the raw carbon support (pH_pzc ≈ 10.5), thus leading to pH_pzc values for the catalysts widely ranging from 1.6 to 9.7. Full article

This study investigates the impact of light exposure on the biotransformation of chalcones in yeast cultures. 4′-Hydroxychalcones, with a hydroxyl group in the A-ring, are characteristic substrates efficiently converted into 4′-hydroxydihydrochalcones—compounds naturally occurring in medicinal plants such as Glycyrrhiza glabra (licorice), Stevia rebaudiana, and Angelica keiskei (ashitaba). These compounds are valued for their bioactivity and are relevant to natural product research. In this research, we present the outcomes of the selective microbial reduction of chalcones to dihydrochalcones using the yeast Yarrowia lipolytica KCh 71, cultivated under both light and dark conditions. The aim was to determine whether light exposure affects the efficiency or selectivity of the transformation. Furthermore, the effect of substrate photoisomerisation induced by light was investigated, as the trans–cis isomerisation of chalcones may affect their availability and affinity toward enzymatic systems. The resulting metabolites were analysed using chromatographic and spectroscopic methods. No significant differences in transformation efficiency were observed between light and dark conditions. In all tested conditions, the 4′-hydroxydihydrochalcones were obtained with high yield, typically exceeding 90% conversion. Additionally, the selective bioreduction of the α,β-unsaturated bond in selected 4′-hydroxychalcones by the studied yeast culture is an exceptionally efficient process. The primary factor influencing the reaction rate is the structure of the substrate, particularly the number and distribution of methoxyl groups on the B-ring. In addition, we establish biocatalytic access to three target dimethoxy dihydrochalcones—4′-hydroxy-2,4-dimethoxydihydrochalcone (5a), 4′-hydroxy-2,5-dimethoxydihydrochalcone (6a), and 4′-hydroxy-3,5-dimethoxydihydrochalcone (7a)—under mild conditions using Yarrowia lipolytica KCh 71. Under preparative-scale conditions (7-day incubation), a minor additional product (≤10%) was detected only for the 4′-hydroxy-2,5-dimethoxydihydrochalcone transformation and identified as 4′,5-dihydroxy-2-methoxydihydrochalcone (6b); no such side reaction was observed in short-term experiments. Full article

This study aimed to enhance the value of agricultural by-products by developing seed melon compound fermented feed (SMFF) using Saccharomyces cerevisiae L23. A two-stage optimization strategy was implemented. First, seed melon juice seed culture medium (SMCM) composition and fermentation conditions were optimized to maximize S. cerevisiae L23 biomass through single-factor and response surface methodology (RSM) approaches. The SMCM medium was optimized to contain 0.06% MgSO₄·7H₂O, 0.2% KH₂PO₄, 0.65% (NH₄)₂SO₄, 0.1% pectinase, and 1.0% urea, and fermentation conditions with inoculation amount, fermentation time, fermentation temperature, and glucose addition were 6%, 28 h, 30 °C, and 0.5%, respectively. Furthermore, SMFF fermentation parameters were optimized via RSM, achieving S. cerevisiae L23 (10.35 lg CFU/g) and sensory evaluation score (83.1) at substrate ratio of 7:3 (seed melon juice: Zanthoxylum bungeanum seed meal), inoculation amount of 8%, and fermentation time of 36 h. Fermentation process significantly improved the nutritional profile of SMFF, increasing crude protein (13%) and vitamin C (VC) content (21%) while reducing neutral detergent fiber/acid detergent fiber (NDF/ADF) levels. SMFF also improved in vitro antioxidant capacity, with higher DPPH, ABTS, hydroxyl radical, and superoxide anion scavenging activities compared to SMFF control. This process efficiently valorized agricultural by-products into nutritionally enriched functional feed. Full article

Background: Gastric cancer ranks fifth among the most prevalent malignancies, with poor prognosis due to limited early-stage diagnosis. Metabolic reprogramming plays a central role in GC development, sustaining carcinogenic processes. Methods: In this study, flow-injection tandem mass spectrometry was used to analyse plasma amino acids and acylcarnitines in 62 gastric cancer patients and 70 healthy individuals. Metabolic profiles were correlated with clinical parameters, tumour histology, and recurrence. Results: Gastric cancer patients showed significantly reduced levels of Trp, Arg, Tyr, Met, and sum of aromatic AAs—metabolites usually implicated in supporting tumour cell growth and proliferation. At the same time, elevated unsaturated, hydroxylated, and dicarboxylic acylcarnitines suggest mitochondrial and peroxisomal dysfunction. Marked metabolic heterogeneity was observed across histological subtypes, with the indeterminate subtype exhibiting the most pronounced disruption in fatty acid oxidation and widespread acylcarnitine alterations. Decreased levels of C6DC-carnitine and Cit synthesis were correlated with higher tumour recurrence, warranting further confirmatory investigations. Conclusions: These findings underscore the value of plasma profiling of amino acids and acylcarnitines for understanding gastric cancer biology, revealing distinct metabolic adaptations reflecting tumour biology, histological subtype, and treatment response. Full article

Background/Objective: The present study reports the design, synthesis, and biological evaluation of novel imidazo-triazole derivatives as potential antidiabetic agents. Methods: The novel series was synthesized by treating amino-triazole bearing carboxylic acid with substituted 2-bromo acetophenone and was biologically compared with acarbose under in vitro analysis. Results: Structure–activity relationship (SAR) analysis revealed that among these compounds, remarkable activity was shown by compound 5 (having three hydroxyl substituents) with IC₅₀ value of 6.80 ± 0.10 and 7.10 ± 0.20 µM for α-amylase and α-glucosidase in comparison to reference drug acarbose. To support experimental findings, computational investigations including molecular docking, pharmacophore modeling, molecular dynamics simulations, density functional theory (DFT), and absorption distribution metabolism excretion and toxicity (ADMET) profiling were employed. These studies confirmed the stability of ligand–protein interactions and provided insights into electronic and reactivity features governing enzyme inhibition. Conclusions: Collectively, the integration of in vitro and in silico approaches underscores the potential of novel imidazo-triazole scaffolds as promising leads for the development of safer and more effective therapeutics against diabetes mellitus. Full article

Background/Objectives: A series of 1-(3,5-dimethoxyphenyl)azetidine-2-ones were synthesised to evaluate their antiproliferative activity in MCF-7 breast cancer cells and HT-29 chemoresistant colon cancer cells. The 1,4-diarylazetidin-2-ones were designed by replacing the characteristic 3,4,5-trimethoxyphenyl Ring A of the antimitotic stilbene combretastatin CA-4 with a 3,5-dimethoxyphenyl substituent at N-1, together with phenyl, hydroxyl, and phenoxy substituents at C-3 of the four-membered ring. Methods: A panel of 12 novel compounds was synthesized and evaluated in estrogen receptor (ER)- and progesterone receptor (PR)-positive MCF-7 breast cancer cells followed with the more potent compounds further evaluated in HT-29 chemoresistant colon cancer cells. Cytotoxicity was determined by LDH assay. The structures of the 1-(3,5-dimethoxyphenyl)azetidine-2-ones 12i, 12k, 12o, 12p together with the 1-(3,5-dimethoxyphenyl)azetidine-2-one 12s were determined by X-ray crystallography. The trans configuration of the C-3 and C-4 substituents of the β-lactam ring was confirmed for compounds 12k and 12u. Molecular modelling and molecular dynamics studies examined the molecular interactions of the compounds with the colchicine binding site of tubulin. Results: The 1-(3,5-Dimethoxyphenyl)-4-(4-ethoxyphenyl)-3-hydroxyazetidin-2-one 12l was identified as the most potent antiproliferative compound in the series (with an IC₅₀ value of 10 nM in MCF-7 breast cancer cells and 3 nM in HT-29 colon cancer cells) and with greater potency than CA-4 in the chemoresistant HT-29 cells. Computational docking studies predicted binding conformations for 12l and the related series of compounds in the colchicine binding site of tubulin and rationalised the impact of the 3,5-dimethoxyphenyl substituent at N-1 of the azetidine-2-one on activity. Conclusions: These findings indicate that the novel 1-(3,5-dimethoxyphenyl)-2-azetidinone 12l is a suitable candidate for further investigation as a potential antiproliferative microtubule-targeting agent for breast and chemoresistant colon cancers. Full article

Four biomass residues–rosemary pomace, rosemary cake, grape seed and apple pomace–were torrefied at 250, 350 and 450 °C, and the physical, chemical and structural changes were characterized. The mass and energy yield decreased with increasing torrefaction temperature; the lowest mass (~10.4%) and energy yield (~10.6%) were observed for rosemary cake torrefied at 450 °C. The HHV increased the most for all feedstocks at 350 °C, with rosemary cake reaching a peak value of 36.4 MJ/kg at 350 °C. Ash content increased with temperature due to organic mass loss, while volatiles decreased and fixed carbon increased in most samples. The FTIR spectra showed the progressive loss of hydroxyl, carbonyl and C–O functionalities and the appearance of aromatic C=C bonds, indicating the formation of the biochar. TGA and DTG analyses revealed that the torrefied samples exhibited higher initial and maximum temperatures for decomposition, confirming improved thermal stability. The TGA-FTIR analyses of gas emissions during pyrolysis and combustion showed that the emissions of CO₂, CH₄, NO_x and SO₂ decreased with increasing degree of torrefaction. Overall, 350 °C was optimal to maximize energy density. The results show that agro-industrial residues can be effectively converted into sustainable biofuels, which offer the dual benefit of reducing waste disposal problems and providing a renewable alternative. In practice, such residues could be used for decentralized power generation in rural areas, co-combustion in existing power plants, or as feedstock for advanced bioenergy systems. Full article

In this study, glass fiber-reinforced polymer (GFRP) rebars were fabricated using epoxy resin matrix filled with 5 wt.% of hemp and bamboo powder fillers, both untreated and dielectric barrier discharge (DBD) plasma treated. The tensile, flexural, transverse shear, and pull-out bond strengths were evaluated to investigate the effects of filler type and surface modification. The results show that the incorporation of untreated fillers decreased tensile strength from 706.4 MPa for hemp to 682.3 MPa for bamboo. The plasma-treated hemp formulation demonstrated a higher recovery (762.1 MPa), approaching the control value (804.2 MPa). Transverse shear strength increased from 117.0 MPa (untreated hemp) to 128.3 MPa (plasma-treated hemp). The bond strength with concrete remained unaffected across all groups. Scanning electron microscopy (SEM) revealed improved filler dispersion, reduced voids, and enhanced resin wetting in the plasma-treated specimens. Fourier-transform infrared spectroscopy (FTIR) confirmed the introduction of polar functional groups such as hydroxyl and carbonyl groups onto the fiber surfaces following plasma exposure. These modifications contributed to improved interfacial adhesion and mechanical integrity. Overall, the DBD plasma treatment effectively enhanced the performance and interfacial characteristics of natural fiber-filled GFRP rebars, supporting their potential as sustainable reinforcements in structural applications. Full article

The study aims to promote environmental restoration by shedding light on the potential use of moringa waste as an inexpensive, eco-friendly adsorbent for treating wastewater contaminated with Chromium (VI). FTIR was used to characterise the surface functional groups of moringa waste. The one-factor-at-a-time method was used to study the initial concentration in milligrams per litre, contact time in minutes, temperature in degrees Celsius, pH, and adsorbent dosage in milligrams per litre. The output was the removal percentage. Furthermore, adsorption isotherms, kinetics, and thermodynamic models were applied to understand the process behaviour. FTIR examination revealed the moringa waste structure’s stability and aromaticity, confirmed by peaks located around 1596 cm⁻¹ and the stretching of the hydroxyl group around 3321 cm⁻¹, which are important for enhancing Cr (VI) adsorption due to their capability to establish strong bonds with metal ions. Aromatic rings contribute to a large surface area and porosity and are stable; this is important for adsorption applications. At 60 min of contact time with a pH of 6 and 0.5 g of adsorbent dosage at 45 °C for a concentration of 100 mg/L, the highest removal percentage was found to be 77.03%. Adsorption data values indicated a good fit to the Langmuir isotherm model. The thermodynamic study showed that the process is endothermic and spontaneous, hence making the application of moringa waste in wastewater treatment viable. Full article

To address the inherent challenge of poor interfacial compatibility in lignin/poly(butylene adipate-co-terephthalate) (PBAT) composites, lignin was extracted from Camellia oleifera shells and subjected to sequential solvent fractionation using ethanol, acetone, and tetrahydrofuran (THF). Two representative fractions—acetone-soluble (ACL) and THF-soluble (THFL)—were selected for composite preparation with PBAT via solvent casting. The influence of lignin fractionation on the structural and performance characteristics of the resulting composites was systematically evaluated through Fourier-transform infrared (FTIR) spectroscopy, the water contact angle (WCA), differential scanning calorimetry (DSC), tensile testing, and scanning electron microscopy (SEM). The results revealed that the abundant hydroxyl groups and benzene rings present in both ACL and THFL facilitated hydrogen bonding and conjugation interactions with the PBAT matrix, significantly improving interfacial adhesion. Notably, the ACL fraction effectively suppressed phase separation and increased the glass transition temperature (T_g) by 1.9 °C, leading to a 13.9% enhancement in tensile strength compared to neat PBAT. More strikingly, the incorporation of only 7 wt% THFL resulted in a remarkable 31% improvement in tensile strength. This substantial enhancement was primarily attributed to the favorable polarity match between THFL and PBAT, as well as the nucleating effect of THFL, which increased the crystallinity of PBAT by 25.3%. This study highlights the effectiveness of sequential lignin fractionation in tailoring the interfacial properties of biodegradable polymer composites. It also provides a promising strategy for the high-value utilization of lignin toward the development of high-performance, environmentally friendly materials. Full article

Industrial pollution caused by Cu(II) ions remains one of the most critical environmental challenges worldwide. A novel green-fluorescent aerogel has been successfully developed for simultaneous sensing and adsorption of Cu(II) through the cross-linking of carboxymethyl nanocellulose and carbon dots (C dots) using epichlorohydrin as a linker. The C dots were synthesized by heating glucose and aspartate mixed solutions at 150 °C. Under UV illumination, the aerogel exhibited intense homogeneous green fluorescence originating from the uniformly dispersed C dots, whose emission can be efficiently quenched by Cu(II) ions. By leveraging smartphone-based imaging, the concentration of Cu(II) was quantified within the range of 5–200 µg/L, with a detection limit of 3.7 µg/L. The adsorption isotherm of Cu(II) onto the aerogel strictly conformed to the Freundlich isotherm model (fitting coefficient R² = 0.9992), indicating a hybrid adsorption mechanism involving both physical adsorption and chemical complexation. The maximum adsorption capacity reached 149.62 mg/g, a value surpassing many reported adsorbents. X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy analyses confirmed that the interactions between the aerogel and Cu(II) involved chelation and redox reactions, mediated by functional groups such as hydroxyl, amino, and carboxyl moieties. The straightforward fabrication process of the aerogel, coupled with its low cost, abundant raw materials, facile synthesis, and superior Cu(II) removal efficiency, positions this bifunctional fluorescent material as a promising candidate for large-scale environmental remediation applications. Full article

BaTiO₃ (BT) is an essential material for many applications due to its dielectric, ferroelectric, and piezoelectric properties; nevertheless, it has been reported to possess a “critical size” in the nanoscale below which its outstanding properties are lost and the paraelectric cubic phase is stabilized at room temperature instead of the tetragonal phase. This value depends on multiple factors, mostly resulting from the synthesis route and conditions. Especially, internal stresses are known to promote the loss of tetragonality. Stresses are commonly present in water-containing synthesis routes because of the incorporation of hydroxyl groups into the oxygen sublattice of BaTiO₃. On the other hand, the use of an organic solvent instead of water as a reaction medium overcomes the mentioned problem. This work presents a one-pot water-free solvothermal treatment of a Ti(O-iPr)₄-Ba(OH)₂·8H₂O sol in methanol in the presence of small amounts of oleic acid, which allows the synthesis of spherical crystalline BT nanoparticles (from ~12 nm to ~30 nm in diameter) at temperatures as low as 100 °C with a cubic/tetragonal crystal structure confirmed by powder XRD, but predominantly tetragonal according to the Raman spectra. The retention of the tetragonal crystal structure is attributed to the lack of lattice hydroxyls (confirmed by FTIR spectroscopy) resulting from the use of an organic solvent (methanol) as reaction medium. To the best of the author’s knowledge, this synthesis approach is the first report of tetragonal BT nanoparticles synthesized in methanol without the addition of extra water and without the need for a post-synthetic calcination step. Full article

Breast milk is the ideal source of nutrition for infant growth and development. However, when nursing mothers consume aflatoxin B₁ (AFB₁)-contaminated food, the hydroxylated form aflatoxin M₁ (AFM₁) is transferred to breast milk and urine. AFB₁ and its metabolite AFM₁ are potent carcinogens and can pose significant risks to food safety and public health worldwide. This study determined the prevalence of AFM₁ in the breast milk and urine of nursing mothers in Bangladesh and estimated infant exposure to this toxin. Breast milk and urine samples (72 each), collected from nursing mothers in three different regions of the country, were analyzed for AFM₁ occurrence via a sensitive enzyme-linked immunosorbent assay (ELISA). AFM₁ was present in 88.9% of urine samples, with a mean concentration of 109.9 ± 52.8 pg/mL, ranging from 40.0 to 223.8 pg/mL. AFM₁ was also detected in 50% of the breast milk samples, with a mean concentration of 4.6 ± 0.7 pg/mL, ranging from 4.0 to 6.1 pg/mL. A strong correlation (r = 0.72) was observed between milk and urinary AFM₁ levels, indicating these as suitable biomarkers of AFB₁ exposure. Yet, no significant correlations were identified between AFM₁ levels in either milk or urine and the food items typically consumed by nursing mothers. The average estimated daily intake (EDI) for AFM₁ with breast milk was 0.59 ng/kg bw/day, with no significant difference between infants (0.57 ng/kg bw/day) and toddlers (0.65 ng/kg bw/day). A comparison of computed EDI ranges for AFM₁ with a proposed tolerable daily intake value resulted in Hazard Indices below 1 for all exposure scenarios. This indicates that the AFM₁ concentrations in breast milk from three regions of Bangladesh raise no concern. Also, the measured levels were far lower than the maximal levels set in the EU regulations for AFM₁ in dairy milk and infant formula (50 ng/kg and 25 ng/kg, respectively). Full article