Search Results (11,671)

Per- and polyfluoroalkyl substances (PFASs), as a class of “permanent chemicals” with high environmental persistence and bioaccumulation, have attracted much attention. In this study, we focused on the molecular mechanism of the interaction between perfluoroalkyl acids (PFAAs) and peroxisome proliferator-activated receptor δ (PPARδ). Using molecular docking, binding free energy calculation, and structural analysis, we systematically investigated the binding modes, key amino acid residues, and binding energies of 20 structurally diverse PFAAs with PPARδ. The results showed that the binding energies of PFAAs with PPARδ were significantly affected by the molecular weight, the number of hydrogen bond donors, and the melting point of PFAAs. PFAAs with smaller molecular weights and fewer hydrogen bond donors showed stronger binding affinity. The binding sites were concentrated in high-frequency amino acid residues such as TRP-256, ASN-269, and GLY-270, and the interaction forces were dominated by hydrogen and halogen bonds. PFAAs with branched structure of larger molecular weight (e.g., 3m-PFOA, binding energy of −2.92 kcal·mol⁻¹; 3,3m₂-PFOA, binding energy of −2.45 kcal·mol⁻¹) had weaker binding energies than their straight-chain counterparts due to spatial site-blocking effect. In addition, validation group experiments further confirmed the regulation law of binding strength by physicochemical properties. In order to verify the binding stability of the key complexes predicted by molecular docking, and to investigate the dynamic behavior under the conditions of solvation and protein flexibility, molecular dynamics simulations were conducted on PFBA, PFOA, 3,3m₂-PFOA, and PFHxA. The results confirmed the dynamic stability of the binding of the high-affinity ligands selected through docking to PPARδ. Moreover, the influence of molecular weight and branched structure on the binding strength was quantitatively verified from the perspectives of energy and RMSD trajectories. The present study revealed the molecular mechanism of PFAAs interfering with metabolic homeostasis through the PPARδ pathway, providing a theoretical basis for assessing its ecological and health risks. Full article

Perfluorooctane sulfonate (PFOS), a persistent and bioaccumulative perfluoroalkyl substance, poses significant environmental and human health risks due to the extraordinary stability of its C–F bonds. Conventional remediation strategies largely fail to achieve mineralization, instead transferring contamination or producing secondary waste streams. In this study, we investigate neutron irradiation as a potential destructive approach for PFOS remediation in both solid and aqueous matrices. Samples were exposed to thermal neutrons (flux: 3.2 × 10⁹ n·cm⁻²·s⁻¹, 0.0025 eV) at the Argonauta reactor for 6 h. Raman and FTIR spectroscopy revealed that PFOS in powder form remained largely resistant to degradation, with only minor structural perturbations observed. In contrast, aqueous PFOS solutions exhibited pronounced spectral changes, including attenuation of C–F and S–O vibrational signatures, the emergence of carboxylate and carbonyl functionalities, and enhanced O–H stretching, consistent with radiolytic oxidation and partial defluorination. Notably, clear peak shifts were predominantly observed for PFOS in aqueous solution after irradiation (overall displacement toward higher wavenumbers), whereas in powdered PFOS the main spectral signature of irradiation was the attenuation of CF₂ and S–O related bands with comparatively limited band relocation. To evaluate the biological relevance of these structural alterations, cell viability assays (MTT) were performed using human umbilical vein endothelial cells. Non-irradiated PFOS induced marked cytotoxicity at 100 and 50 μg/mL (p < 0.0001), whereas neutron-irradiated PFOS no longer exhibited significant toxicity, with cell viability comparable to the control. These findings indicate a matrix-dependent response: neutron scattering in solids yields negligible molecular breakdown, whereas radiolysis-driven pathways in water facilitate measurable PFOS transformation. The cytotoxicity assay demonstrates that neutron irradiation promotes sufficient molecular degradation of PFOS in aqueous media to suppress its cytotoxic effects. Although complete mineralization was not achieved under the tested conditions, the combined spectroscopic and biological evidence supports neutron-induced radiolysis as a promising pathway for perfluoroalkyl detoxification. Future optimization of neutron flux, irradiation duration, and synergistic catalytic systems may enhance mineralization efficiency. Because PFOS concentration, fluoride release (F⁻), and TOC were not quantified in this study, remediation was assessed through spectroscopic fingerprints of transformation and the suppression of cytotoxicity, rather than by mass-balance mineralization metrics. This study highlights neutron irradiation as a promising strategy for perfluoroalkyl destruction in contaminated water sources. Full article

In African countries and many developing countries, communal farmers rely on livestock such as cattle, goats, and sheep to support food security, income, and agricultural activities. Fertility in these animals is often limited by poor semen quality, which reduces sperm concentration, total motility, and morphology. Assisted reproductive biotechnologies, including semen cryopreservation and artificial insemination, are increasingly essential to enhance reproductive efficiency and productivity. Although cryopreservation preserves valuable genetic material, it can damage sperm cells, making high-quality extenders critical for protection. Common extenders, such as Tris-egg yolk glucose, citrate-sugar-based, and skimmed milk solutions, supply nutrients and protect sperm membranes. To further minimize oxidative stress, antioxidants are incorporated, with growing interest in plant-derived compounds. Many plants contain bioactive substances, including antioxidants and phytomelatonin, which can enhance sperm quality safely and effectively. This review examines the use of plant-based antioxidants during semen cryopreservation and highlights their potential to improve fertility in mammalian livestock. Full article

Endocrine-disrupting chemicals (EDCs), widespread in aquatic environments, interfere with endocrine function in organisms and threaten ecosystem stability. Rotifers, critical live feed for marine fish, shrimp, and crab larvae, link EDC-induced reproductive impairment to marine ecosystem stability and aquaculture sustainability. This PRISMA-compliant review synthesizes key findings, consequences, and gaps in EDC–rotifer reproductive toxicity research. Traditional EDCs (heavy metals, per- and polyfluoroalkyl substances (PFASs), phenols, phthalate esters, polybrominated diphenyl ethers (PBDEs), and steroid hormones) and emerging EDCs (disinfection byproducts, microplastics, pharmaceutical metabolites) induce distinct reproductive harm—e.g., Hg²⁺ shows extreme toxicity (24 h LC₅₀ = 4.51 μg L⁻¹ in Brachionus plicatilis), BDE-47 damages ovaries, and microplastics cause transgenerational delays. Rotifer species and exposure duration affect sensitivity (e.g., BDE-47: 96 h LC₅₀ = 0.163 mg L⁻¹ vs. 24 h LC₅₀ > 22 mg L⁻¹ in B. plicatilis). Oxidative stress is a universal mechanism, and combined EDC exposure produces context-dependent synergistic/antagonistic effects. EDC-induced impairment reduces rotifer population density, alters structure, and propagates through food webs, threatening aquaculture and biodiversity; transgenerational toxicity (e.g., 4-nonylphenol: F₁ inhibition 28% vs. 12% in F₀) weakens resilience. This review supports EDC risk assessment, with gaps including long-term low-concentration data, transgenerational mechanisms, EDC–microbiome interactions, and emerging PFAS toxicity—priorities for future research. Full article

Synthetic cathinones are cathinone analogues that humans have artificially created. The first compounds appeared on the European market in 2005. They belong to a class of drugs called stimulants, classified as new psychoactive substances. Synthetic cathinones are very popular; people use these drugs because they are cheaper “substitutes” for other stimulants. They produce psychostimulant and hallucinogenic effects similar to cocaine, amphetamine, and MDMA, among others. Despite their presence on the market for several years, the precise toxicological impacts of these compounds on the human body remain unknown. Studies were conducted on the effects of selected cathinones (mephedrone, clephedrone) on blood cells: erythrocytes and platelets. The effect of cathinones was determined by measuring the surface density of biological membranes using microelectrophoresis. The continued popularity of these compounds, coupled with limited knowledge of their precise effects on the human body, makes the problem significant and requires ongoing research. Based on the results obtained for mephedrone and clephedrone, it can be concluded that at the tested concentrations (170 ng/mL and 2700 ng/mL), they alter the surface charge density of the biological membranes of red blood cells and platelets. Full article

Over the last 15 years, mixture risk assessment for food xenobiotics has evolved from conceptual discussions and simple screening tools, such as the Hazard Index (HI), towards operational, component-based and probabilistic frameworks embedded in major food-safety institutions. This review synthesizes methodological and regulatory advances in cumulative risk assessment for dietary “cocktails” of pesticides, contaminants and other xenobiotics, with a specific focus on food-relevant exposure scenarios. At the toxicological level, the field is now anchored in concentration/dose addition as the default model for similarly acting chemicals, supported by extensive experimental evidence that most environmental mixtures behave approximately dose-additively at low effect levels. Building on this paradigm, a portfolio of quantitative metrics has been developed to operationalize component-based mixture assessment: HI as a conservative screening anchor; Relative Potency Factors (RPF) and Toxic Equivalents (TEQ) to express doses within cumulative assessment groups; the Maximum Cumulative Ratio (MCR) to diagnose whether risk is dominated by one or several components; and the combined Margin of Exposure (MOET) as a point-of-departure-based integrator that avoids compounding uncertainty factors. Regulatory frameworks developed by EFSA, the U.S. EPA and FAO/WHO converge on tiered assessment schemes, biologically informed grouping of chemicals and dose addition as the default model for similarly acting substances, while differing in scope, data infrastructure and legal embedding. Implementation in food safety critically depends on robust exposure data streams. Total Diet Studies provide population-level, “as eaten” exposure estimates through harmonized food-list construction, home-style preparation and composite sampling, and are increasingly combined with conventional monitoring. In parallel, human biomonitoring quantifies internal exposure to diet-related xenobiotics such as PFAS, phthalates, bisphenols and mycotoxins, embedding mixture assessment within a dietary-exposome perspective. Across these developments, structured uncertainty analysis and decision-oriented communication have become indispensable. By integrating advances in toxicology, exposure science and regulatory practice, this review outlines a coherent, tiered and uncertainty-aware framework for assessing real-world dietary mixtures of xenobiotics, and identifies priorities for future work, including mechanistically and data-driven grouping strategies, expanded use of physiologically based pharmacokinetic modelling and refined mixture-sensitive indicators to support public-health decision-making. Full article

Microbial contamination of food is a crucial cause of food spoilage and foodborne diseases, posing a severe threat to global public health. Although chemical preservatives are effective, their potential hazards to human health and the environment, coupled with the growing demand for “clean label” products, have driven the search for natural alternatives. Lactic acid bacteria (LAB), recognized as the Generally Recognized as Safe (GRAS) microorganisms, have emerged as the promising bio-preservatives due to their safety, effectiveness, and multifunctionality. This review systematically summarized the core antimicrobial properties of LAB, including their inhibitory spectrum against foodborne pathogens, spoilage microorganisms, viruses, parasites, and their ability to degrade toxic substances such as mycotoxins, pesticides, and heavy metals. Key inhibitory mechanisms of LAB are highlighted, encompassing the production of antimicrobial metabolites, leading to metabolism disruption and cell membrane damage, nutrition and niche competition, quorum-sensing interference, and anti-biofilm formation. Furthermore, recent advances in LAB applications in preserving various food matrices (meat, dairy products, fruits and vegetables, cereals) are integrated, including their roles in enhancing food sensory quality, extending shelf life, and retaining nutritional value. The review also discusses critical factors influencing LAB’s inhibitory activity (medium composition, culture conditions, ionic components, pathway regulator, etc.) and the challenges associated with the application of LAB. Finally, future research directions are outlined, including the novel LAB and metabolites exploration, AI-driven cultural condition optimization, genetic engineering application, nano-encapsulation and active packaging development, and building up the LAB-based cellular factories. In conclusion, LAB and their antimicrobial metabolites hold great promise as green and safe food preservatives. This review is to provide comprehensive theoretical support for the rational improvement and efficient application of LAB-based natural food preservatives, contributing to the development of a safer and more sustainable food processing and preservation systems. Full article

Magnetic nanoparticles (MNPs) are widely applied in biomedicine, including bioimaging, drug delivery, and cell tracking. As central mediators of immune surveillance, macrophages phagocytize foreign substances, rendering their interactions with MNPs particularly consequential. During MNP uptake, macrophages undergo cytoplasmic remodeling that can lead to morphological alterations. Although prior studies have predominantly focused on MNP uptake efficiency and cytotoxicity, systematic quantitative assessments of macrophage morphological alterations following MNP treatment remain scarce. In this study, phase-contrast microscopy images of macrophages before and after MNP treatment were analyzed using unsupervised variational autoencoder (VAE)-based frameworks. Specifically, the β-VAE, β-total correlation VAE, and multi-encoder VAE frameworks were employed to extract latent representations of cellular morphology. The analysis revealed that MNP-treated macrophages exhibited pronounced structural alterations, including membrane expansion, central density shifts, and shape distortions. These findings were further substantiated through quantitative evaluations, including effect size analysis, kernel density estimation, latent traversal, and difference mapping. Collectively, these results demonstrate that VAE-based unsupervised learning provides a robust framework for detecting subtle morphological responses of macrophages to nanoparticle exposure and highlights its broader applicability across varied cell types, treatment conditions, and imaging platforms. Full article

Background: The coordinated improvement of yield, quality and resistance is a primary goal in rice breeding. Gene editing technology is a novel method for precise multiplex gene improvement. Methods: In this study, we constructed a multiplex CRISPR/Cas9 vector targeting yield-related genes (GS3, OsPIL15, Gn1a), fragrance gene (OsBADH2) and rice blast resistance gene (Pi21) to pyramid traits for enhanced yield, quality, and disease resistance in rice. A tRNA-assisted CRISPR/Cas9 multiplex gene editing vector, M601-OsPIL15/GS3/Gn1a/OsBADH2/Pi21-gRNA, was constructed. Genetic transformation was performed using the Agrobacterium-mediated method with the japonica rice variety Xin Dao 53 as the recipient. Mutation editing efficiency was detected in T₀ transgenic plants. Grain length, grain number per panicle, thousand-grain weight, 2-acetyl-1-pyrroline (2-AP) content, and rice blast resistance of homozygous lines were measured in the T₃ generations. Results: Effectively edited plants were obtained in the T₀ generation. The simultaneous editing efficiency for all five genes reached 9.38%. The individual gene editing efficiencies for Pi21, GS3, OsBADH2, Gn1a, and OsPIL15 were 78%, 63%, 56%, 54%, and 13%, respectively. Five five-gene homozygous edited lines with two genotypes were selected in the T₂ generation. In the T₃ generation, compared with the wild-type (WT), the edited homozygous lines showed increased grain number per panicle (14.60–25.61%), increased grain length (7.39–11.16%), increased grain length–width ratio (8.37–13.02%), increased thousand-grain weight (3.79–9.15%), a 42–64 folds increase in the fragrant substance 2-AP content, and significantly enhanced rice blast resistance. Meanwhile, there were no significant changes in other agronomic traits. Conclusions: CRISPR/Cas9-mediated multiplex gene editing technology enabled the simultaneous editing of genes related to rice yield, quality, and disease resistance. This provides an effective approach for obtaining new japonica rice germplasm with blast resistance, long grains, and fragrance. Full article

This study investigated the effect of superheated steam (SS) assisted glycosylation modification on the flavor profile of oyster peptides (OP), and explored the correlation between key flavor compounds and glycosylation degree using Gas Chromatography–Ion Mobility Spectrometry (GC-IMS) and nano-scale Liquid Chromatography coupled with High-Resolution Mass Spectrometry (nano-LC/HRMS). The results indicated that SS treatment accelerated the glycosylation process, reduced free amino groups level, and distinguished their unique flavor through E-nose. GC-IMS analysis detected 64 signal peaks including 13 aldehydes, 6 ketones, 7 esters, 6 alcohols, 2 acids, 2 furans and 5 other substances. And it was revealed that SS-mediated glycosylation treatment reduced the levels of fishy odorants like Heptanal and Nonanal, while promoting the pleasant-smelling alcohols and esters. In addition, Pearson correlation showed a positive correlation between excessive glycation and the increase in aldehydes, which might cause the recurrence of undesirable fishy notes. Further nano-LC/HRMS analysis revealed that arginine and lysine acted as the main sites for glycosylation modification. Notably, glycosylated peptides such as KAFGHENEALVRK, DSRAATSPGELGVTIEGPKE, generated by mild SS treatment could convert into ketones and pyrazines in subsequent reactions, thereby contributing to overall sensory enhancement. In conclusion, SS treatment at 110 °C for 1 min significantly improved the flavor quality of OP and sustains improvement in subsequent stages, providing theoretical support for flavor optimization of oyster peptides. Full article

Microbial fermentation is an important means to enhance the nutrition and functionality of food, and soybean fermentation has a long history and a wide variety of products. This study systematically compared the effects of fermentation and post-ripening processes of Bacillus subtilis natto JLCC513 on the nutritional components, active substances, and sensory characteristics of soybeans. The experimental results showed that, in terms of basic nutrition, fermentation led to a significant decrease in fat and reducing sugar content, followed by an initial increase and then a decrease in total protein content. In contrast, water-soluble protein continued to increase, and the total amount of free amino acids surged. The active nutritional indicators before and after soybean fermentation showed that nattokinase activity continued to increase during fermentation and post-ripening. At the same time, the number of viable bacteria decreased slightly during post-ripening. The increase in the proportion of easily absorbed aglycone-type isoflavones before and after soybean fermentation is accompanied by a sustained increase in vitamin K2 and gamma aminobutyric acid (GABA) content. In terms of sensory quality, color-difference analysis shows a decrease in brightness (L value) and an increase in redness (a value), resulting in the characteristic yellow-brown color of natto. In terms of texture characteristics, the hardness decreases, while the viscosity and elasticity are significantly enhanced. Through GC-IMS analysis of volatile aromas during soybean fermentation and post-ripening, it was found that esters (such as ethyl acetate) and pyrazines (such as 2,3-dimethylpyrazine) increased, and the product flavor shifted from grassy to fruity and nutty. In summary, natto bacteria enhance the digestibility, nutritional value, and sensory acceptance of soybeans through enzymatic hydrolysis and metabolic transformation. The post-ripening stage plays a key role in flavor maturation and further accumulation of active ingredients. Full article

The microbial ecology of acid mine drainage (AMD) systems in Armenia, with a long mining history, remains unexplored. This study aimed to characterize the microbial diversity and functional potential of AMD in the Syunik region and to isolate novel microorganisms with biotechnological value. A comprehensive analysis of the microbial communities’ structure of Kavart abandoned, Kapan exploring mines effluent, and Artsvanik tailing was conducted. Metagenomics revealed bacterial-dominated communities, comprising Pseudomonadota (previously “Proteobacteria”) (68–72%), with site-specific variations in genus abundance. A high abundance and diversity of metal resistance genes (MRGs), particularly for copper and arsenic, were identified. Carbohydrate-active enzyme (CAZy) analysis showed a dominance of GT2 and GT4 genes, suggesting a high potential for extracellular polymeric substances (EPS) production and biofilm formation. A novel strain of iron-oxidizing bacteria Arm-12 was isolated that shares only ~90% similarity with known Leptospirillum type species, indicating it may represent a new genus without culturable representatives. The strain exhibits enhanced copper extraction from concentrate. This study provides the first metagenomic insights into Armenian AMD systems and tailing, revealing a unique community rich in metal resistance and biofilm-forming genes. The isolation of a novel highly effective iron-oxidizer Arm-12 highlights the potential of AMD environments as a source of novel taxa with significant applications in biomining and bioremediation processes. Full article

The study investigates the use of silver nanoparticles (AgNPs) in agriculture, focusing on their potential to enhance the immune response of potato (Solanum tuberosum L.) plants against phytopathogenic attacks. The research highlights how AgNPs, stabilized by biologically active polymers polyhexamethylene biguanide and tallow amphopolycarboxyglycinate, can induce oxidative stress. Triple foliar application of 0.1–9.0 g/ha silver nanoparticles at the budding and later stages demonstrated significant efficacy in suppressing diseases caused by Phytophthora infestans and Alternaria solani (over 60%). This effect was linked to the increased activity of peroxidase—over 30–50%—and the decreased catalase activity, indicative of a well-coordinated oxidative stress response to the invasion of P. infestans and A. solani. The results suggest that AgNPs in low concentrations can prime the plant’s innate immune system, enhancing its resistance without detrimental effects on growth parameters, thus contributing to the improved crop yield. These findings underscore the potential of AgNPs not as traditional biocides, but as intelligent elicitors of plant-induced resistance, positioning them as next-generation tools for sustainable crop protection and yield optimization, which can be applied at extremely low doses (less than 10 g/ha of active substance). Full article

Procyanidins, a class of substances widely distributed in nature, have attracted the attention of the scientific community due to their bioactive properties, especially with regard to human health. This review is based on an extensive examination of peer-reviewed literature, patents, and clinical trial reports published between 2005 and 2025. From an initial pool of more than 300 documents, 283 studies were selected according to criteria of scientific rigor, methodological clarity, and relevance to the research objectives. A literature search was performed using PubMed, PubChem, Google Scholar, Scopus and ResearchGate employing keywords such as Procyanidins, chemical structure, extraction, and health effects. This article provides a comprehensive overview of current methods for obtaining these compounds, which include both natural sources and synthetic approaches. It provides a concise summary of the molecular structure of procyanidins and emphasizes the importance of understanding their conformational features for predicting biological activity. The challenges of establishing correlations between the structural features of procyanidins and their properties are described. In addition, this article explores the many potential applications of these compounds, spanning both biochemistry and the field of design and synthesis of novel materials. This review provides a comprehensive evaluation of Procyanidins, focusing on their geometrical conformation analysis through advanced NMR spectroscopy techniques including homonuclear correlation (COSY, TOCSY), heteronuclear one-bond (HSQC, HMQC), multiple-bond (HMBC) experiments, and through-space correlation (NOESY) in conjunction with various extraction methodologies. Full article

Melanin produced in melanocytes contributes to photoprotection, oxidative stress reduction, immune regulation, and epidermal homeostasis, while its dysregulation underlies diverse pigmentary disorders. Natural products modulate melanogenesis by regulating tyrosinase activity, intracellular signaling pathways such as extracellular signal-regulated kinase/mitogen-activated protein kinase (ERK/MAPK) and cyclicAMP/protein kinase A/cAMP response element-binding protein (cAMP/PKA/CREB), and cellular redox balance. Anti-melanogenic effects have been reported for various fruit-derived phytochemicals, ginseng-based metabolites, and plant polyphenols, which act through direct enzymatic inhibition, suppression of melanoenic signaling, modulation of melanosome dynamics, and antioxidant or anti-inflammatory activities. Advances in delivery systems, including nano- and microencapsulation platforms, further enhance the stability and topical bioavailability of these compounds. In contrast, certain methoxylated flavonoids and phenolic constituents can stimulate pigmentation by sustaining melanogenic signaling and promoting microphthalmia-associated transcription factor (MITF)-driven transcription, emphasizing the context-dependent and bidirectional influence of natural substances on pigmentation outcomes. Collectively, these findings highlight the therapeutic potential of natural product-based modulators of melanogenesis while underscoring the need for mechanistic clarification, safety evaluation, and translational studies to ensure effective and controlled pigmentation management. This review summarizes the biological functions of melanin and examines natural strategies for regulating pigmentation. Full article