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20 pages, 3036 KiB  
Article
Chemometric Approach for Discriminating the Volatile Profile of Cooked Glutinous and Normal-Amylose Rice Cultivars from Representative Japanese Production Areas Using GC × GC-TOFMS
by Takayoshi Tanaka, Junhan Zhang, Shuntaro Isoya, Tatsuro Maeda, Kazuya Hasegawa and Tetsuya Araki
Foods 2025, 14(15), 2751; https://doi.org/10.3390/foods14152751 - 6 Aug 2025
Abstract
Cooked-rice aroma strongly affects consumer choice, yet the chemical traits distinguishing glutinous rice from normal-amylose japonica rice remain underexplored because earlier studies targeted only a few dozen volatiles using one-dimensional gas chromatography–mass spectrometry (GC-MS). In this study, four glutinous and seven normal Japanese [...] Read more.
Cooked-rice aroma strongly affects consumer choice, yet the chemical traits distinguishing glutinous rice from normal-amylose japonica rice remain underexplored because earlier studies targeted only a few dozen volatiles using one-dimensional gas chromatography–mass spectrometry (GC-MS). In this study, four glutinous and seven normal Japanese cultivars were cooked under identical conditions, their headspace volatiles trapped with MonoTrap and qualitatively profiled by comprehensive GC × GC-TOFMS. The two-dimensional platform resolved 1924 peaks—about ten-fold previous coverage—and, together with hierarchical clustering, PCA, heatmap visualization and volcano plots, cleanly separated the starch classes (78.3% cumulative PCA variance; Euclidean distance >140). Volcano plots highlighted 277 compounds enriched in the glutinous cultivars and 295 in Koshihikari, including 270 compounds that were not previously documented in rice. Normal cultivars were dominated by ethers, aldehydes, amines and other nitrogenous volatiles associated with grainy, grassy and toasty notes. Glutinous cultivars showed abundant ketones, furans, carboxylic acids, thiols, steroids, nitro compounds, pyrroles and diverse hydrocarbons and aromatics, yielding sweeter, fruitier and floral accents. These results expand the volatile library for japonica rice, provide molecular markers for flavor-oriented breeding and demonstrate the power of GC × GC-TOFMS coupled with chemometrics for grain aroma research. Full article
14 pages, 950 KiB  
Article
Synthesis and Antifungal Evaluation Against Candida spp. of 5-Arylfuran-2-Carboxamide Derivatives
by Salvatore Mirabile, Giovanna Ginestra, Rosamaria Pennisi, Davide Barreca, Giuseppina Mandalari and Rosaria Gitto
Microorganisms 2025, 13(8), 1835; https://doi.org/10.3390/microorganisms13081835 - 6 Aug 2025
Abstract
Candidiasis arises from the proliferation of Candida species in the human body, especially in individuals with compromised immune systems. Efficient therapeutic management of candidiasis is often hampered by the limited availability of potent antifungal drugs and the emergence of drug-resistant strains. We have [...] Read more.
Candidiasis arises from the proliferation of Candida species in the human body, especially in individuals with compromised immune systems. Efficient therapeutic management of candidiasis is often hampered by the limited availability of potent antifungal drugs and the emergence of drug-resistant strains. We have previously identified the N-[(4-sulfamoylphenyl)methyl][1,1′-biphenyl]-4-carboxamide to have fungistatic and fungicidal properties, likely due to the hydrophobic biphenyl–chemical features affecting the structural organization of Candida spp. cell membrane. Here, we designed and synthesized a novel series of twelve 5-arylfuran-2-carboxamide derivatives bearing a new hydrophobic tail as bioisosteric replacement of the diphenyl fragment. Its antifungal effectiveness against C. albicans, C. glabrata, and C. parapsilosis, including ATCC and clinically isolated strains, was assessed for all compounds. The most active compound was N-benzyl-5-(3,4-dichlorophenyl)furan-2-carboxamide (6), with fungistatic and fungicidal effects against C. glabrata and C. parapsilosis strains (MIC = 0.062–0.125 and 0.125–0.250 mg/mL, respectively). No synergistic effects were observed when combined with fluconazole. Interestingly, fluorescent microscopy analysis after staining with SYTO 9 and propidium iodide revealed that compound 6 affected the cell membrane integrity in C. albicans strain 16. Finally, carboxamide 6 exhibited a dose-dependent cytotoxicity on erythrocytes, based on assessing the LDH release. Full article
(This article belongs to the Collection Feature Papers in Antimicrobial Agents and Resistance)
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12 pages, 498 KiB  
Article
Virulence of Metarhizium robertsii Strains Isolated from Forest Ecosystems Against Wax Moths (Galleria mellonella, Achroia grisella) and Pine Processionary (Thaumetopoea pityocampa) Larvae
by Spiridon Mantzoukas, Vasileios Papantzikos, Chrysanthi Zarmakoupi, Panagiotis A. Eliopoulos, Ioannis Lagogiannis and George Patakioutas
Biology 2025, 14(8), 1009; https://doi.org/10.3390/biology14081009 - 6 Aug 2025
Abstract
Entomopathogenic fungi (EPF) are one of the most environmentally friendly ways to control a plethora of chewing insects such as T. pityocampa, G. mellonella, and A. grisella. Bioassay of EPF on these highly damaging pests is considered important in the [...] Read more.
Entomopathogenic fungi (EPF) are one of the most environmentally friendly ways to control a plethora of chewing insects such as T. pityocampa, G. mellonella, and A. grisella. Bioassay of EPF on these highly damaging pests is considered important in the face of climate change in order to research alternative solutions that are capable of limiting chemical control, the overuse of which increases insects’ resistance to chemical compounds. In this study, the insecticidal virulence of Metarhizium robertsii isolates, retrieved from forest ecosystems, was tested on second-instar larvae of T. pityocampa, G. mellonella, and A. grisella. Bioassays were carried out in the laboratory, where experimental larvae were sprayed with 2 mL of a six-conidial suspension from each isolate. Mortality was recorded for 144 h after exposure. Mean mortality, lethal concentrations, sporulation percentage, and sporulation time were estimated for each isolate. Metarhizium isolates resulted in the highest mortality (89.2% for G. mellonella and 90.2% for A. grisella). Based on the LC50 estimates determined by the concentration–mortality relationships for the tested fungal isolates, we demonstrated significant virulence on larvae of G. mellonella, A. grisella, and T. pityocampa. Our results indicate that entomopathogenic fungi have the potential to become a very useful tool in reducing chemical applications. Full article
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14 pages, 3011 KiB  
Article
Ameliorative Effects of Soybean Powder Fermented by Bacillus subtilis on Constipation Induced by Loperamide in Rats
by Gi Soo Lee, Su Kang Kim, Ju Yeon Ban and Chung-Hun Oh
Int. J. Mol. Sci. 2025, 26(15), 7615; https://doi.org/10.3390/ijms26157615 - 6 Aug 2025
Abstract
Constipation is a prevalent gastrointestinal disorder that significantly impairs quality of life. While pharmacological agents such as loperamide are widely used to induce constipation in experimental models, there is increasing interest in natural alternatives for alleviating intestinal dysfunction. In this study, we investigated [...] Read more.
Constipation is a prevalent gastrointestinal disorder that significantly impairs quality of life. While pharmacological agents such as loperamide are widely used to induce constipation in experimental models, there is increasing interest in natural alternatives for alleviating intestinal dysfunction. In this study, we investigated the laxative effects of soybean powder fermented by Bacillus subtilis DKU_09 in a loperamide-induced rat model of constipation. The probiotic strain was isolated from cheonggukjang, a traditional Korean fermented soybean paste, and its identity was confirmed through 16S rRNA sequencing. Fermented soybean powder was characterized morphologically via scanning electron microscopy and chemically via HPLC to assess its isoflavone content. Rats were administered loperamide (5 mg/kg) for four days to induce constipation and were then treated with fermented soybean powder at doses of 100, 200, or 300 mg/kg. No pharmacological laxatives (e.g., PEG) were used as a positive control; instead, values from the treatment groups were compared with those from the loperamide-only constipation group. Key outcomes of fecal output, water content, colonic fecal retention, and gastrointestinal transit ratio were measured. The fermented product significantly improved stool frequency and moisture content, reduced colonic fecal retention, and restored gastrointestinal transit in a dose-dependent manner. Notably, the 300 mg/kg group demonstrated nearly complete recovery of fecal parameters without affecting body weight. Statistical analysis was performed using one-way ANOVA followed by Tukey’s post hoc test. These findings suggest that Bacillus subtilis-fermented soybean powder exerts synergistic laxative effects through the combined action of probiotic viability and fermentation-enhanced bioactive compounds such as aglycone isoflavones. This study supports the potential use of fermented soybean-based nutraceuticals as a natural and safe intervention for constipation and gastrointestinal dysregulation. Full article
(This article belongs to the Special Issue Functions and Applications of Natural Products)
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31 pages, 3977 KiB  
Article
Exploring the Cytokinin Profile of Doliocarpus dentatus (Aubl.) Standl. From Guyana and Its Relationship with Secondary Metabolites: Insights into Potential Therapeutic Benefits
by Ewart A. Smith, Ainsely Lewis, Erin N. Morrison, Kimberly Molina-Bean, Suresh S. Narine and R. J. Neil Emery
Metabolites 2025, 15(8), 533; https://doi.org/10.3390/metabo15080533 - 6 Aug 2025
Abstract
Background/Objectives: Possessing red and white ecotypes, and utilized in traditional Guyanese medicine, Doliocarpus dentatus’ red ecotype is preferred locally for its purported superior therapeutic efficacy. Although therapeutic metabolites were detected in D. dentatus previously, phytohormones remain largely unexplored, until now. Cytokinins, [...] Read more.
Background/Objectives: Possessing red and white ecotypes, and utilized in traditional Guyanese medicine, Doliocarpus dentatus’ red ecotype is preferred locally for its purported superior therapeutic efficacy. Although therapeutic metabolites were detected in D. dentatus previously, phytohormones remain largely unexplored, until now. Cytokinins, phytohormones responsible for plant cell division, growth and differentiation, are gaining traction for their therapeutic potential in human health. This study screened and quantified endogenous cytokinins and correlated detected cytokinins with selected secondary metabolites. Methods: Liquid chromatography–mass spectrometry was used to acquire phytohormone and metabolite data. Bioinformatics tools were used to assess untargeted metabolomics datasets via statistical and pathway analyses, and chemical groupings of putative metabolites. Results: In total, 20 of the 35 phytohormones were detected and quantified in both ecotypes, with the red ecotype displaying higher free base and glucoside cytokinin concentrations and exhibited 6.2 times the total CK content when compared to the white ecotype. Pathway analysis revealed flavonoid and monoterpenoid biosynthesis in red and white ecotypes, respectively. Positive correlations between specific cytokinins and alkaloids, and between trans-Zeatin and isopentenyladenosine riboside with phenolic compounds were observed. Conclusions: These results suggest that the red ecotype’s elevated cytokinin levels coupled with flavonoid biosynthesis enrichment support its preference in Guyanese traditional medicine. Full article
(This article belongs to the Section Plant Metabolism)
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22 pages, 775 KiB  
Review
Bioactive Compounds, Technological Advances, and Sustainable Applications of Avocado (Persea americana Mill.): A Critical Review
by Amanda Priscila Silva Nascimento, Maria Elita Martins Duarte, Ana Paula Trindade Rocha and Ana Novo Barros
Foods 2025, 14(15), 2746; https://doi.org/10.3390/foods14152746 - 6 Aug 2025
Abstract
Avocado (Persea americana), originally from Mesoamerica, has emerged as a focus of intense scientific and industrial interest due to its unique combination of nutritional richness, bioactive potential, and technological versatility. Its pulp, widely consumed across the globe, is notably abundant in [...] Read more.
Avocado (Persea americana), originally from Mesoamerica, has emerged as a focus of intense scientific and industrial interest due to its unique combination of nutritional richness, bioactive potential, and technological versatility. Its pulp, widely consumed across the globe, is notably abundant in monounsaturated fatty acids, especially oleic acid, which can comprise over two-thirds of its lipid content. In addition, it provides significant levels of dietary fiber, fat-soluble vitamins such as A, D, E and K, carotenoids, tocopherols, and phytosterols like β-sitosterol. These constituents are consistently associated with antioxidant, anti-inflammatory, glycemic regulatory, and cardioprotective effects, supported by a growing body of experimental and clinical evidence. This review offers a comprehensive and critical synthesis of the chemical composition and functional properties of avocado, with particular emphasis on its lipid profile, phenolic compounds, and phytosterols. It also explores recent advances in environmentally sustainable extraction techniques, including ultrasound-assisted and microwave-assisted processes, as well as the application of natural deep eutectic solvents. These technologies have demonstrated improved efficiency in recovering bioactives while aligning with the principles of green chemistry. The use of avocado-derived ingredients in nanostructured delivery systems and their incorporation into functional foods, cosmetics, and health-promoting formulations is discussed in detail. Additionally, the potential of native cultivars and the application of precision nutrition strategies are identified as promising avenues for future innovation. Taken together, the findings underscore the avocado’s relevance as a high-value matrix for sustainable development. Future research should focus on optimizing extraction protocols, clarifying pharmacokinetic behavior, and ensuring long-term safety in diverse applications. Full article
(This article belongs to the Special Issue Feature Review on Nutraceuticals, Functional Foods, and Novel Foods)
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16 pages, 858 KiB  
Review
Unraveling the Core of Endometriosis: The Impact of Endocrine Disruptors
by Efthalia Moustakli, Anastasios Potiris, Themos Grigoriadis, Athanasios Zikopoulos, Eirini Drakaki, Ioanna Zouganeli, Charalampos Theofanakis, Angeliki Gerede, Athanasios Zachariou, Ekaterini Domali, Peter Drakakis and Sofoklis Stavros
Int. J. Mol. Sci. 2025, 26(15), 7600; https://doi.org/10.3390/ijms26157600 - 6 Aug 2025
Abstract
Globally, endometriosis affects almost 10% of reproductive-aged women, leading to chronic pain and discomfort. Endocrine-disrupting compounds (EDCs) seem to play a pivotal role as a causal factor. The current manuscript aims to explain potential molecular pathways, synthesize current evidence regarding EDCs as causative [...] Read more.
Globally, endometriosis affects almost 10% of reproductive-aged women, leading to chronic pain and discomfort. Endocrine-disrupting compounds (EDCs) seem to play a pivotal role as a causal factor. The current manuscript aims to explain potential molecular pathways, synthesize current evidence regarding EDCs as causative agents of endometriosis, and highlight implications in the general population and clinical work. A thorough review of experimental, epidemiologic, and mechanistic research studies was conducted to explain the association between EDCs and endometriosis. Among the primary EDCs under investigation are polychlorinated biphenyls, dioxins, phthalates, and bisphenol A (BPA). Despite methodological heterogeneity and some discrepancies, epidemiologic evidence supports a positive association between some increased levels of BPA, phthalates, and dioxins in urine or in blood, and endometriosis. Experiments support some effect of EDCs on endometrial cells and causing endometriosis. EDCs function as xenoestrogens, alter immune function, induce oxidative stress, and disrupt progesterone signaling. Epigenetic reprogramming may play a role in mediating EDC-induced endometriosis. Endocrine, immunological, and epigenetic pathways link EDCs and endometriosis. Prevention techniques require deeper comprehension of those factors. Causal linkages and possible treatment targets should be based on longitudinal studies and multi-omics techniques. Restriction of EDCs could be beneficial for endometriosis prevalence limitation. Full article
(This article belongs to the Section Molecular Pathology, Diagnostics, and Therapeutics)
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29 pages, 3173 KiB  
Article
Graph Neural Networks for Sustainable Energy: Predicting Adsorption in Aromatic Molecules
by Hasan Imani Parashkooh and Cuiying Jian
ChemEngineering 2025, 9(4), 85; https://doi.org/10.3390/chemengineering9040085 (registering DOI) - 6 Aug 2025
Abstract
The growing need for rapid screening of adsorption energies in organic materials has driven substantial progress in developing various architectures of equivariant graph neural networks (eGNNs). This advancement has largely been enabled by the availability of extensive Density Functional Theory (DFT)-generated datasets, sufficiently [...] Read more.
The growing need for rapid screening of adsorption energies in organic materials has driven substantial progress in developing various architectures of equivariant graph neural networks (eGNNs). This advancement has largely been enabled by the availability of extensive Density Functional Theory (DFT)-generated datasets, sufficiently large to train complex eGNN models effectively. However, certain material groups with significant industrial relevance, such as aromatic compounds, remain underrepresented in these large datasets. In this work, we aim to bridge the gap between limited, domain-specific DFT datasets and large-scale pretrained eGNNs. Our methodology involves creating a specialized dataset by segregating aromatic compounds after a targeted ensemble extraction process, then fine-tuning a pretrained model via approaches that include full retraining and systematically freezing specific network sections. We demonstrate that these approaches can yield accurate energy and force predictions with minimal domain-specific training data and computation. Additionally, we investigate the effects of augmenting training datasets with chemically related but out-of-domain groups. Our findings indicate that incorporating supplementary data that closely resembles the target domain, even if approximate, would enhance model performance on domain-specific tasks. Furthermore, we systematically freeze different sections of the pretrained models to elucidate the role each component plays during adaptation to new domains, revealing that relearning low-level representations is critical for effective domain transfer. Overall, this study contributes valuable insights and practical guidelines for efficiently adapting deep learning models for accurate adsorption energy predictions, significantly reducing reliance on extensive training datasets. Full article
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33 pages, 4268 KiB  
Review
Targeting Bacterial Biofilms on Medical Implants: Current and Emerging Approaches
by Alessandro Calogero Scalia and Ziba Najmi
Antibiotics 2025, 14(8), 802; https://doi.org/10.3390/antibiotics14080802 - 6 Aug 2025
Abstract
Biofilms are structured communities of microorganisms encased in a self-produced extracellular matrix, and they represent one of the most widespread forms of microbial life on Earth. Their presence poses serious challenges in both environmental and clinical settings. In natural and industrial systems, biofilms [...] Read more.
Biofilms are structured communities of microorganisms encased in a self-produced extracellular matrix, and they represent one of the most widespread forms of microbial life on Earth. Their presence poses serious challenges in both environmental and clinical settings. In natural and industrial systems, biofilms contribute to water contamination, pipeline corrosion, and biofouling. Clinically, biofilm-associated infections are responsible for approximately 80% of all microbial infections, including endocarditis, osteomyelitis, cystic fibrosis, and chronic sinusitis. A particularly critical concern is their colonization of medical devices, where biofilms can lead to chronic infections, implant failure, and increased mortality. Implantable devices, such as orthopedic implants, cardiac pacemakers, cochlear implants, urinary catheters, and hernia meshes, are highly susceptible to microbial attachment and biofilm development. These infections are often recalcitrant to conventional antibiotics and frequently necessitate surgical revision. In the United States, over 500,000 biofilm-related implant infections occur annually, with prosthetic joint infections alone projected to incur revision surgery costs exceeding USD 500 million per year—a figure expected to rise to USD 1.62 billion by 2030. To address these challenges, surface modification of medical devices has emerged as a promising strategy to prevent bacterial adhesion and biofilm formation. This review focuses on recent advances in chemical surface functionalization using non-antibiotic agents, such as enzymes, chelating agents, quorum sensing quenching factors, biosurfactants, oxidizing compounds and nanoparticles, designed to enhance antifouling and mature biofilm eradication properties. These approaches aim not only to prevent device-associated infections but also to reduce dependence on antibiotics and mitigate the development of antimicrobial resistance. Full article
(This article belongs to the Special Issue Antibacterial and Antibiofilm Properties of Biomaterial)
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10 pages, 2101 KiB  
Article
Structural and Ferromagnetic Response of B2-Type Al45Mn41.8X13.2 (X = Fe, Co, Ni) Alloys
by Esmat Dastanpour, Haireguli Aihemaiti, Shuo Huang, Valter Ström, Lajos Károly Varga and Levente Vitos
Magnetochemistry 2025, 11(8), 67; https://doi.org/10.3390/magnetochemistry11080067 - 6 Aug 2025
Abstract
To our knowledge, no magnetic B2 phase in the Al–Mn system of near-equiatomic compositions has been reported so far. Here, we investigate the structural and magnetic characteristics of Al45Mn41.8X13.2 (X = Fe, Co or Ni) alloys. We demonstrate [...] Read more.
To our knowledge, no magnetic B2 phase in the Al–Mn system of near-equiatomic compositions has been reported so far. Here, we investigate the structural and magnetic characteristics of Al45Mn41.8X13.2 (X = Fe, Co or Ni) alloys. We demonstrate that adding 13.2 atomic percent magnetic 3d metal to AlMn stabilizes a ferromagnetic B2 structure, where Al and X occupy different sublattices. We employ density functional theory calculations and experimental characterizations to underscore the role of the late 3d metals for the phase stability of the quasi-ordered ternary systems. We show that these alloys possess large local magnetic moments primarily due to Mn atoms partitioned to the Al-free sublattice. The revealed magneto-chemical effect opens alternative routes for tailoring the magnetic properties of B2 intermetallic compounds for various magnetic applications. Full article
(This article belongs to the Special Issue Advances in Functional Materials with Tunable Magnetic Properties)
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22 pages, 2670 KiB  
Review
Sodium Chloride in Food
by Sylwia Chudy, Agnieszka Makowska and Ryszard Kowalski
Foods 2025, 14(15), 2741; https://doi.org/10.3390/foods14152741 - 6 Aug 2025
Abstract
Sodium chloride is a chemical compound that has been encountered by people for thousands of years, and plays a significant role in their lives. The aim of this article is to provide a comprehensive review of table salt from the perspective of health, [...] Read more.
Sodium chloride is a chemical compound that has been encountered by people for thousands of years, and plays a significant role in their lives. The aim of this article is to provide a comprehensive review of table salt from the perspective of health, food technology, and cultural heritage. The article discusses salt extraction and production, its composition and consumption, and its effects on the human body. The authors draw attention to new trends, such as the use of micronized salt, microencapsulated salt, and salt with colors and shapes that differ from those of typical table salt. Scientific studies on the presence of undesirable substances and the use of salt additives were reviewed. The role of salt in dairy, meat, and bakery technology was illustrated. Gaps in research on salt were highlighted. In the last part, all types of salt with geographical indications are shown. The paper suggests that producers with a long tradition in the salt sector should apply for the European geographical indications to enhance their national and cultural heritage and promote their region. The review highlights the need for further research on all aspects discussed. Full article
(This article belongs to the Section Food Quality and Safety)
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22 pages, 5509 KiB  
Article
Kinetic Analysis of Thermal Degradation of Styrene–Butadiene Rubber Compounds Under Different Aging Conditions
by Imen Hamouda, Masoud Tayefi, Mostafa Eesaee, Meysam Hassanipour and Phuong Nguyen-Tri
J. Compos. Sci. 2025, 9(8), 420; https://doi.org/10.3390/jcs9080420 - 6 Aug 2025
Abstract
This study examined the impact of storage and operational aging on the thermal stability, structural degradation, and electrical properties of styrene–butadiene rubber (SBR) compound by analyzing three distinct materials: a laboratory-stored sample, an operationally aged one, and an original unaged reference. Thermal degradation [...] Read more.
This study examined the impact of storage and operational aging on the thermal stability, structural degradation, and electrical properties of styrene–butadiene rubber (SBR) compound by analyzing three distinct materials: a laboratory-stored sample, an operationally aged one, and an original unaged reference. Thermal degradation was analyzed through thermogravimetric analysis (TGA), which examined weight loss as a function of temperature and time at different heating rates. Results showed that the onset temperature and peak position in the 457 °C to 483 °C range remained stable. The activation energy (Ea) was determined using the Kissinger–Akahira–Sunose (KAS), Flynn–Wall–Ozawa (FWO), and Friedman methods, with the original unaged sample’s (OUS) Ea averaging 203.7 kJ/mol, decreasing to 163.47 kJ/mol in the laboratory-stored sample (LSS), and increasing to 224.18 kJ/mol in the operationally aged sample (OAS). The Toop equation was applied to estimate the thermal degradation lifetime at a 50% conversion rate. Since the material had been exposed to electricity, the evolution of electrical conductivity was studied and found to have remained stable after storage at around 0.070 S/cm. However, after operational aging, it showed a considerable increase in conductivity, to 0.321 S/cm. Scanning Electron Microscopy (SEM) was employed to analyze microstructural degradation and chemical changes, providing insights into the impact of aging on thermal stability and electrical properties. Full article
(This article belongs to the Special Issue Mechanical Properties of Composite Materials and Joints)
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20 pages, 1523 KiB  
Article
Structural and Vibrational Characterizations of Alizarin Red S
by César A. N. Catalán, Licínia L. G. Justino, Rui Fausto, Gulce O. Ildiz and Silvia Antonia Brandán
Molecules 2025, 30(15), 3286; https://doi.org/10.3390/molecules30153286 - 5 Aug 2025
Abstract
In this work, the structures of the isolated anion and anhydrous and monohydrated sodium salts of alizarin red S (ARS) have been theoretically investigated within the density functional theory framework (B3LYP/6-311++G** calculations). The combination of calculations with the scaled quantum mechanics force field [...] Read more.
In this work, the structures of the isolated anion and anhydrous and monohydrated sodium salts of alizarin red S (ARS) have been theoretically investigated within the density functional theory framework (B3LYP/6-311++G** calculations). The combination of calculations with the scaled quantum mechanics force field (SQMFF) methodology has allowed the assignment of the experimental infrared spectrum of ARS in the solid phase and the determination of the corresponding force constants. The structural analysis also included the investigation of the NMR and UV-visible spectra of the compound in solution in light of the undertaken quantum chemical calculations, the obtained theoretical data being in good agreement with the corresponding experimental ones. The impact of the presence of the Na+ counterion and hydration water on the properties of the organic ARS fragment was evaluated. Atoms in molecules theory (AIM) analysis was also undertaken to obtain further details on the electronic structure of the investigated species, and the HOMO-LUMO gap was determined to evaluate their relative reactivity. Globally, the results obtained in this work extend the available information on alizarin red S and may also be used for the fast identification of the three studied species of the compound investigated (anhydrous and monohydrated sodium salts and isolated anion). Full article
(This article belongs to the Section Molecular Structure)
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15 pages, 961 KiB  
Article
Analysis of Chemical Composition and Odor Characteristics in Particleboards Decorated by Resin-Impregnated Paper, Polypropylene Film and Polyvinyl Chloride Film
by Liming Zhu, Minghui Yang, Lina Tang, Qian Chen, Xiaorui Liu, Xianwu Zou, Yuejin Fu and Bo Liu
Polymers 2025, 17(15), 2145; https://doi.org/10.3390/polym17152145 - 5 Aug 2025
Abstract
Analysis of changes in TVOC and VOCs chemical composition or odor characteristics of particleboard before and after decoration treatment with resin-impregnated paper (RIP), polypropylene (PP) film and polyvinyl chloride (PVC) film were studied. The effects of these three decoration treatments on masking or [...] Read more.
Analysis of changes in TVOC and VOCs chemical composition or odor characteristics of particleboard before and after decoration treatment with resin-impregnated paper (RIP), polypropylene (PP) film and polyvinyl chloride (PVC) film were studied. The effects of these three decoration treatments on masking or suppressing the release of VOCs and odorants from particleboard were explored. The substances that were covered or suppressed and newly introduced before and after processing were identified to provide a basis for reducing the odor emissions of PVC-, PP- and RIP-decorated particleboard. Taking undecorated particleboard and particleboard treated by three types of decorative materials as research subjects, the air permeability of the three decorative materials was tested using the Gurley Permeability Tester. TVOC emissions from the boards were evaluated using the 1 m3 environmental chamber method. Qualitative and quantitative analyses of the samples were conducted via thermal desorption–gas chromatography–mass spectrometry (TD-GCMS). The contribution of odor substances was determined using odor activity value (OAV). The results indicated that the permeability from high to low was PVC film, PP film and RIP. Compared with undecorated particleboard, the TVOC emissions of PVC-decorated boards decreased by 93%, PP-decorated particleboard by 83% but the TVOC emissions of RIP-decorated particleboard increased by 67%. PP decoration treatment masked or suppressed the release of 20 odor substances but introduced xylene, which can increase potentially the health risks for PP-decorated particleboard. PVC decoration treatment masked or suppressed 19 odor substances, but it introduced 12 new compounds, resulting in an overall increase in TVOC emissions. RIP treatment did not introduce new odor substances. After PP film and RIP treatments, both the variety of VOCs released and the number of key odor-contributing compounds and modifying odorants decreased. In contrast, the number of modifying odorants and potential odorants increased after PVC treatment. VOC emissions were effectively masked or suppressed by three decoration treatments, same as the release of substances contributing to overall odor of particleboard was reduced. Among them, PP and RIP decorative materials demonstrate better effects. Full article
(This article belongs to the Special Issue Eco-Friendly Supramolecular Polymeric Materials, 2nd Edition)
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19 pages, 847 KiB  
Article
Characterization and Selection of Lycium barbarum Cultivars Based on Physicochemical, Bioactive, and Aromatic Properties
by Juan Carlos Solomando González, María José Rodríguez Gómez, María Ramos García, Noelia Nicolás Barroso and Patricia Calvo Magro
Horticulturae 2025, 11(8), 924; https://doi.org/10.3390/horticulturae11080924 (registering DOI) - 5 Aug 2025
Abstract
Goji berries (Lycium barbarum L.) are considered a functional food due to their high content of bioactive compounds with demonstrated health benefits. This study evaluated four cultivars (G3, G4, G5, and G7) grown under Mediterranean climate conditions, focusing on their physicochemical properties [...] Read more.
Goji berries (Lycium barbarum L.) are considered a functional food due to their high content of bioactive compounds with demonstrated health benefits. This study evaluated four cultivars (G3, G4, G5, and G7) grown under Mediterranean climate conditions, focusing on their physicochemical properties (total soluble solids, titratable acidity, and pH), bioactive compound (sugars and organic acids, total and individual phenolic and carotenoid compounds, and antioxidant activities (DPPH and CUPRAC assay)), and aromatic profiles (by GC-MS) to assess their suitability for fresh consumption or incorporation into food products. G4 exhibited the most favorable physicochemical characteristics, with the highest total soluble solids (20.2 °Brix) and sugar content (92.8 g 100 g−1 dw). G5 stood out for its lower titratable acidity (0.34%) and highest ripening index (54.8), indicating desirable flavor attributes. Concerning bioactive compounds, G3 and G4 showed the highest total phenolic content (17.9 and 19.1 mg GAE g−1 dw, respectively), with neochlorogenic acid being predominant. G4 was notable for its high carotenoid content, particularly zeaxanthin (1722.6 μg g−1 dw). These compounds significantly contributed to antioxidant activity. Volatile organic compound (VOC) profiles revealed alcohols and aldehydes as the dominant chemical families, with hexanal being the most abundant. G5 and G7 exhibited the highest total VOC concentrations. Principal component analysis grouped G3 and G4 based on their high sugar and phenolic content, while G5 and G7 were characterized by their complex aromatic profiles. Therefore, G3 and G4 are promising candidates for fresh consumption and potential functional applications, while G5 and G7 are particularly suitable for new product development due to their nutraceutical and aromatic value. Full article
(This article belongs to the Section Postharvest Biology, Quality, Safety, and Technology)
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