Search Results (521)

The toxicity of copper (Cu) severely affects the growth and physiological metabolism of plants. 2-(3,4-Dichlorophenoxy) triethylamine (DCPTA) is a plant growth regulator known to enhance plant tolerance to various abiotic stresses; however, its specific role in mitigating Cu toxicity via cell wall modulation and nitrogen metabolism remains unclear. “Zhongnong 26” (Cucumis sativus L.) seedlings were subjected to a randomized block design with four treatments: control (CK), 0.25 mg/L DCPTA, 50 μM Cu, and 50 μM Cu + 0.25 mg/L DCPTA, with three biological replicates per treatment. The results indicated that DCPTA application significantly alleviated Cu-induced growth inhibition. Specifically, DCPTA improved root system architecture by markedly increasing total root length (68.8%), surface area (68.7%), and the number and length of secondary lateral roots (69.6%, 173.2%). Furthermore, DCPTA enhanced the biosynthesis of cell wall polysaccharides—including pectin (24.3%), hemicellulose 1 (22.4%), hemicellulose 2 (23.7%) and cellulose (33.1%) in roots. Fourier Transform Infrared (FTIR) spectroscopy analysis revealed that DCPTA modified functional groups (e.g., –OH, –COOH) within the cell wall, enhancing their metal-chelating capacity. Consequently, DCPTA promoted the immobilization of Cu in the root cell wall fractions (particularly pectin and HC2) and shifted Cu into less toxic, pectate- and protein-bound forms, thereby reducing its translocation to leaves. Additionally, DCPTA restored the activities of key nitrogen metabolism enzymes in leaves and roots. Compared with Cu treatment alone, nitrate reductase (NR) activity increased by 77.7% and 90.6%, while glutamine synthetase (GS) activity remained stable, and glutamate synthase (GOGAT) activity increased by 10.3% and 71.3% in leaves and roots, respectively. In conclusion, DCPTA enhances copper sequestration in roots by coordinating the regulation of root structure and cell wall strengthening (with an increase in pectin and hemicellulose content). This is crucial for protecting the nitrogen metabolism within the cells (including the enzymes that drive the nitrate–ammonium reduction pathway) to maintain metabolic balance under Cu stress. Full article

In response to the plastic pollution crisis, bioplastics emerged as a sustainable alternative. However, low degradation rate and abiotic decomposition generate micro- and nanoplastics. These particles enter the food chain, establishing oral intake as a key route of human exposure. This review gathered studies on the biotransformation of bioplastics in the gastrointestinal tract and on their toxicity in human cells and murine models. Most studies focused on polylactic acid particles due to widespread use in food packaging. Under simulated gastrointestinal conditions in vitro, particles were modulated, resulting in cavity and pore formation, fragmentation, lipase competition, protein corona formation, and alterations in the gut microbiota (including Selenomonadaceae, Bifidobacterium, and Prevotellaceae). Also, particle breakdown increases surface area, enhancing interactions with biomeiolecules and causing higher in vitro and in vivo toxicity. Indeed, pro-inflammatory cytokine secretion, oxidative stress induction, and redox imbalance were found in both models. In mice, alterations in gut microbiota involving Bacillales indirectly mediated hepatotoxicity, leading to uric acid and triglyceride accumulation. Furthermore, microbiota adaptation over time was suggested with an increase in microorganisms and the potential conversion of L-lactic into harmful D-lactic acid. Despite limited studies, this review highlighted that ingested bioplastic-derived micro- and nanoplastics can lead to toxic effects. Full article

The accumulation of aquatic organisms on submerged surfaces causes major economic and environmental impacts in marine ecosystems. Conventional antifouling biocides pose risks due to toxicity to non-target species and bioaccumulation. Nature-inspired compounds such as flavonoids have emerged as more sustainable alternatives. Aiming to assess the environmental impact of new antifouling flavonoids and to evaluate the toxicity of their transformation products, this study investigates the degradation of three promising antifouling flavonoids (chalcone CC345G and dihydrochalcones DH345 and DH345P) in aqueous matrices. Comprehensive abiotic and biotic degradation assays (hydrolysis, photodegradation, and biodegradation) were conducted. Appropriate liquid chromatography with UV detection methods were developed and validated to monitor the studies. The glycosylated chalcones bearing a triazole moiety CC345G revealed no detectable degradation under any of the experimental conditions. In contrast, both dihydrochalcones underwent significant abiotic degradation; DH345 was more susceptible to hydrolysis at pH 7.10 (17.41% degradation), while DH345P was more prone to photolysis in sterilized natural seawater at pH 8.82 (45.82–54.52% degradation), also showing substantial degradation in hydrolysis (24.34–42.41%) and biodegradation (33.43–41.07%). Overall, the prenylated dihydrochalcone DH345P exhibited the highest degradation rate among the tested compounds. Analysis with high-resolution mass spectrometry disclosed several transformation products in degradation assays, and one chemical structure was proposed. Preliminary ecotoxicity assessment performed on the degradation products using Artemia salina indicated low toxicity, suggesting minimal environmental impact. Full article

Accurately monitoring the surface stabilization of waste dumps in open-pit coal mines is critical for hazard prevention and ecological reclamation. In arid and semi-arid regions, traditional optical remote sensing vegetation indices suffer from a systematic “response lag” in assessing physical stability due to the slow establishment of pioneer vegetation. To overcome this biological limitation, this study proposes a quantitative spatiotemporal monitoring framework based on time-series Interferometric Synthetic Aperture Radar (InSAR) coherence to detect early-stage geotechnical stabilization. Using Sentinel-1 imagery of the Balongtu coal mine, a sliding-window detection algorithm was developed to capture the physical transition of surface electromagnetic scattering mechanisms from active disturbance to stable consolidation. The main findings are as follows: (1) Statistical analysis identified a critical geophysical coherence threshold of 0.15, which effectively and objectively distinguishes active dumping disturbance zones from structurally stable areas. (2) The spatiotemporal evolution dynamics of the completed dump areas from 2017 to 2023 were successfully characterized, revealing that 87.6% of the open-pit areas achieved physical stabilization within three years post-mining, with a spatial distribution highly consistent with the objective operational rule of “mining first, dumping later”. (3) Accuracy assessment using 700 spatiotemporally balanced validation points—derived through strict visual interpretation of high-resolution optical imagery—demonstrated high algorithm reliability, achieving overall accuracies (OA) of 87.57% and 90.43% at half-yearly and annual monitoring intervals, respectively. By decoupling physical surface stabilization from optical greenness, this study provides a timely abiotic precursor indicator, offering scientific, quantitative decision support for precision ecological zoning and accelerated land turnover approval in mining areas. Full article

The emergence of membrane boundaries represents a decisive transition in the origin of life, yet the molecular nature of the earliest abiotic membranes remains uncertain. Existing models based on simple fatty acids, while experimentally tractable, often lack the environmental robustness required under fluctuating prebiotic conditions. Furthermore, the absence of clear pathways linking primitive amphiphiles to later phospholipid systems highlights the need for chemically continuous intermediate frameworks. Here, we explore borate-bridged amphiphile–carbohydrate conjugates as plausible intermediates between simple prebiotic surfactants and modern lipid bilayers. These conjugates arise from low-molecular-weight polyols—including glycerol, butane-1,2,3,4-tetraol, pentane-1,2,3,4,5-pentaol, and hexane-1,2,3,4,5,6-hexitol—reacting with long-chain alkyl ethers and borate species under alkaline conditions, enabling reversible coupling to ribose and other vicinal diol-containing sugars. This chemistry integrates three essential properties for early compartmentalization: hydrolytically robust ether-linked hydrophobic domains, multivalent and highly hydrated headgroups, and environmentally responsive borate coordination. Comparative physicochemical analysis suggests that single-tail alkylglycerol derivatives preferentially form micelles and interfacial films, while di- and tri-tail tetritol and pentitol conjugates favor lamellar assemblies and vesicle formation across realistic prebiotic pH and salinity ranges. Hexitol-based systems, particularly those bearing three hydrophobic chains, may act as membrane-stabilizing components that enhance rigidity and reduce permeability under extreme conditions. We propose that heterogeneous mixtures dominated by two-tail polyol diethers, supplemented by tri-tail stabilizers and surface-active alkylglycerols, could provide mechanically robust, pH-tunable, and sugar-decorated abiotic membranes. Such borate-mediated amphiphiles offer a chemically coherent framework linking carbohydrate stabilization, ether lipid persistence, and dynamic self-assembly, potentially representing a transitional stage in the evolutionary pathway from primitive amphiphilic films to biologically encoded membranes. Full article

Soil salinity is a major abiotic stressor that constrains plant growth and development, yet the coordinated regulatory mechanisms underlying salt stress impacts on plant cell mechanical properties and the cytoskeleton remain elusive. In this study, tobacco suspension cells were employed as a model system. Combining mechanical measurements, fluorescence microscopy imaging, and bright-field morphological observation, we systematically characterized the dynamic response patterns of cell-generated surface stress (ΔS), cell viscoelastic index (CVI), microfilament cytoskeleton structure, as well as cell morphology and plasmolysis under NaCl stress ranging from 50 to 150 mmol/L. The results revealed three distinct response thresholds: 50 mmol/L NaCl treatment induced only transient ΔS fluctuations and mild plasmolysis, with no significant changes in CVI or microfilament fluorescence intensity, suggesting a safe tolerance threshold. The 75–100 mmol/L NaCl treatments triggered reversible “rise–recovery” mechanical responses in ΔS and CVI. The microfilament cytoskeleton showed minor structural adjustments, and plasmolysis increased gradually but remained reversible, defining this range as a reversible acclimation phase. The 125–150 mmol/L NaCl treatment caused an irreversible decline in ΔS (with a sharp instantaneous drop at 150 mmol/L). CVI variations diminished and stabilized after 6 h. The microfilament cytoskeleton suffered progressive disruption, as fluorescence intensity dropped to 1% of the control group at 150 mmol/L, accompanied by severe plasmolysis and protoplast shrinkage, indicating irreversible cellular damage. These findings demonstrate a concentration-dependent gradient effect of NaCl stress, highlighting tight coordination between mechanical properties, cytoskeletal integrity, and morphological adaptation. This work provides critical cytological insights into the molecular regulation of plant salt stress responses. Full article

Candida parapsilosis is a major cause of healthcare-associated infections due to its persistence on abiotic surfaces and efficient transmission via healthcare workers’ hands. This study evaluated the antifungal efficacy and safety of clinically relevant antiseptics against 60 C. parapsilosis clinical isolates using a surface carrier test designed to simulate contamination and disinfection events on hospital surfaces. Antifungal activity was assessed by logarithmic reduction (log₁₀) assays on surface carriers and by minimum inhibitory concentration (MIC) testing. Potential synergistic interactions between antiseptics and selected phytochemicals were investigated using checkerboard assays, and toxicity was evaluated in vivo using Caenorhabditis elegans. Surface carrier assays showed that 70% ethanol and 0.5% alcoholic chlorhexidine (CHG) achieved the highest fungicidal activity, with reductions of up to 5 log₁₀ after 1 min exposure at 25 °C. Polyhexamethylene guanidine hydrochloride (PHMGH) displayed consistently low MIC values (0.4–0.9 ppm) and intermediate surface activity. CHG combined with eugenol or menthol produced strong synergistic interactions, reducing CHG MICs from up to 6250 ppm to as low as 20 ppm (>300-fold). Toxicity assays revealed a narrow safety margin for CHG, whereas PHMGH showed a more gradual concentration-dependent toxicity profile. These findings highlight clinically relevant differences in antiseptic performance and identify combination strategies that may reduce CHG exposure while maintaining antifungal efficacy. Full article

Apple (Malus domestica Borkh.) is the most widely cultivated deciduous fruit tree with the largest industrial scale and the highest economic value in China. Fruit surface glossiness and plant stress tolerance are two core traits that determine the economic benefits and sustainable development of the apple industry. The plant epidermal cuticle is not only the core material basis for determining fruit glossiness but also the first barrier for plants to resist abiotic and biotic stresses. Glycosylphosphatidylinositol-anchored lipid transfer proteins (LTPGs) are the core functional factors mediating trans-cell wall lipid transport in plants. At present, the functions and action mechanisms of LTPG family members that simultaneously regulate fruit appearance quality and stress tolerance in apple remain largely unclear. In this study, we took the MdLTPG17 gene as the research object, clarified its biological function of stress resistance under drought stress, and dissected the molecular mechanism by which it mediates fruit glossiness formation via regulating fruit cuticle thickening. The results of this study provide important genetic resources and a theoretical basis for molecular breeding of stress resistance and targeted improvement of fruit appearance quality in apple. Full article

The synergistic effects of glucose (Glu) concentration and clay mineral type (kaolinite [Kao], montmorillonite [Mon]) on abiotic humification via the polyphenol-Maillard reaction remain poorly understood. To address these scientific challenges, a series of controlled, sterile batch experiments was conducted. Specifically, a glucose concentration gradient (0, 0.03, 0.06, 0.12, and 0.24 mol/L) was established; Kao and Mon were separately introduced as mineral catalysts; and the Maillard reaction was facilitated in the presence of catechol and glycine under strictly abiotic conditions to preclude any potential biological interference. Comprehensive analyses were performed on the reaction products—namely, the supernatant and the dark-brown residue generated during the reaction process. These analyses included: the E₄/E₆ ratio and total organic carbon (TOC) content of the supernatant; the carbon-based ratio of humic-like acid to fulvic-like acid (C_HLA/C_FLA); and the structural characteristics of humic-like acid (HLA) isolated from the dark-brown residue. Results showed dynamic E₄/E₆ ratio and TOC changes in the supernatant were accurately described by the Logistic function. Kao favored soluble organic C accumulation and enhanced retention of early-stage, low-molecular-weight intermediates in the dark-brown residue, while Mon promoted humic-like substances (HLS) polymerization and aromatic condensation. FTIR spectroscopy analysis identified optimal Glu thresholds for maximal HLS formation—0.03 mol/L for Kao and 0.06 mol/L for Mon—indicating non-linear, rather than monotonic, dependence on Glu dosage. Comparative pre- and post-reaction Fourier-transform infrared (FTIR) spectroscopy further demonstrated that Mon, owing to Mg–OH octahedral sites arising from isomorphic substitution, formed more stable Cat chelates than Kao. These chelates effectively stabilized surface-bound hydroxyl-associated water molecules and modulated the electron cloud distribution around Si–O bonds. Collectively, this study clarified the dual regulatory role of Glu concentration and clay mineral identity in abiotic humification pathways, advanced mechanistic understanding of clay mineral-mediated polyphenol-Maillard reactions, and established a scientific foundation for optimizing humification efficiency in both engineered and natural systems. Full article

Land-use change contributes significantly to climate change mitigation through biophysical changes (albedo, α) and biogeochemical (greenhouse gases, GHG) emissions (here refers to methane, CH₄, and nitrous oxide, N₂O). While the impact of grassland–cropland conversion on global warming potential (GWP) is well-documented globally, research remains scarce in the saline-alkaline agropastoral transition zone (APTZ) of the western Songnen Plain, Northeast China, an ecotone uniquely characterized by soil-crusting and seasonal inundation. We conducted in situ bi-weekly measurements of N₂O and CH₄ fluxes (June–September) to acquire growing season ${\mathrm{GWP}}_{{\mathrm{N}}_2\mathrm{O}}$ and ${\mathrm{GWP}}_{{\mathrm{C}\mathrm{H}}_4}$, alongside α. The study compared an undisturbed fenced meadow (FMD) with three adjacent land-use types, clipped meadow (CMD), saline-alkaline meadow (SAL), and paddy rice field (PDY), converted from FMD from 2018 to 2022. Annual α-induced GWP (GWPΔα) was positive across all converted sites (CMD, SAL, and PDY), indicating a warming effect due to lower α compared to FMD. The PDY exhibited the highest CH₄ emission (5.04 kg CO₂ m⁻² yr⁻¹), exceeding other land uses by three orders of magnitude (p < 0.05). Conversely, N₂O emissions remained consistently minimal and stable across all sites. When integrating the net ecosystem exchange of CO₂ (NEE), the PDY functioned as a net warming source. In contrast, the warming effects of α and non-CO₂ GHGs were effectively offset by the NEE in other land uses. Machine learning identified soil water content (SWC) as the dominant predictor of α across all land uses in growing season. However, a mechanistic divergence was observed, i.e., α in low saline-alkali ecosystems (FMD, CMD and PDY) was shaped by coupled biotic and soil moisture controls, whereas in the degraded SAL ecosystem, α is almost exclusively abiotic-driven. These findings demonstrate that land-use conversion in the Songnen Plain governs complex land-surface feedbacks through distinct pathways. This study provides a quantitative framework for integrating biophysical and biogeochemical impacts to optimize land management for climate resilience in saline-alkaline agropastoral ecotones. Full article

Candidozyma auris (formerly Candida auris) is an emerging multidrug-resistant pathogenic fungus with an increased ability to cause outbreaks in healthcare facilities, leading to poor patient outcomes. Since its initial discovery in 2009, C. auris has spread rapidly across continents and is now classified by both the Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO) as a critical-priority pathogen. This review summarizes current knowledge on the origin, taxonomy, microbiology, and virulence mechanisms of C. auris, emphasizing its thermotolerance, osmotolerance, and biofilm-forming capacity on biotic and abiotic surfaces, as well as aspects related to its antifungal drug resistance and management. These features, together with its genomic plasticity, contribute to persistence, transmission, and drug resistance. Emerging evidence also supports a potential link between climate change and C. auris evolution, highlighting environmental adaptation as a driver of pathogenicity. Combating C. auris will require multidisciplinary efforts to mitigate its expanding global impact. Full article

Saline-alkali stress restricts crop yield by disrupting nutrient and water uptake, ionic balance, and oxidative homeostasis. Although myo-inositol enhances tolerance to abiotic stress, its role in sugar beet (Beta vulgaris L.) under saline-alkali conditions remains unclear. To investigate the effects of exogenous myo-inositol on sugar beet growth under saline-alkali soils, a pot experiment was conducted using six myo-inositol concentrations (0, 0.2, 0.4, 0.6, 0.8, and 1.0 g L⁻¹). Myo-inositol significantly influenced plant performance in a concentration-dependent manner. The 0.6 g L⁻¹ treatment produced the highest shoot and root fresh and dry weights, nearly doubling shoot biomass compared with the control. Shoot N and P contents increased markedly at 0.6 g L⁻¹, while their concentrations remained relatively stable, indicating biomass-driven nutrient accumulation. Myo-inositol reduced Na accumulation while maintaining stable K, Ca, and Mg concentrations, thereby improving ionic balance. Antioxidant capacity was enhanced, with superoxide dismutase and catalase activities significantly elevated. Root total length and surface area increased substantially, whereas specific root length and surface area decreased, suggesting improved root morphological development. Soil alkaline phosphatase activity was also stimulated at higher myo-inositol treatments. Overall, moderate myo-inositol application (with regression analysis indicating an optimum of approximately 0.56 g L⁻¹) improved sugar beet growth through enhanced nutrient acquisition, ionic balance, antioxidant capacity, and root development, offering practical insights for its use as a growth regulator in saline-alkali crop production. Full article

Staphylococcus epidermidis is a leading opportunistic pathogen in medical device-associated infections due to its ability to adhere to abiotic materials and develop biofilms that are difficult to eradicate. This study investigated the antibiofilm potential of an ethanolic extract of the red seaweed Gracilaria fisheri and its purified constituent, N-benzylcinnamamide, against S. epidermidis. Antibacterial activity was determined, and antibiofilm effects were assessed using the crystal violet assay and confocal laser scanning microscopy (CLSM). Early bacterial adhesion on glass and polyurethane (PU) surfaces was measured. The effect on catheter-associated biofilms was evaluated by scanning electron microscopy (SEM). Transcripts of biofilm- and quorum-sensing-associated genes (icaA and luxS) were assessed by semi-quantitative RT-PCR. Cytotoxicity was evaluated by MTT assay. At 200 µg/mL, biofilm biomass decreased to 48.21 ± 5.52% with the extract and to 36.65 ± 6.82% with N-benzylcinnamamide. CLSM time-course imaging showed delayed biofilm maturation and less consolidated, discontinuous structures. Surface exposure to the extract markedly reduced early attachment on both materials. On PU catheter segments, SEM demonstrated that N-benzylcinnamamide markedly reduced surface coverage and disrupted three-dimensional biofilm architecture. At the molecular level, transcription of icaA and luxS was reduced. Both the extract and N-benzylcinnamamide showed minimal cytotoxicity in HeLa cells. These findings support further evaluation of these marine-derived agents as candidates for antibiofilm surface treatments to reduce early medical device colonization. Full article

Microplastics are persistent contaminants in coastal wetlands, yet the mechanisms of their microbial transformation remain poorly understood. This study examined the interactions between a wetland sediment-derived microbial consortium and polyethylene terephthalate (PET) fibers over a 60-day incubation. After 60 days, the consortium caused a PET weight loss of 13.7 ± 0.9%, whereas the abiotic control showed a less than 2% loss. The water contact angle decreased from 77.5 ± 1.2° to 75.8 ± 0.4°, suggesting enhanced surface hydrophilicity. Multi-scale surface analyses (SEM, WCA, and FTIR) confirmed progressive microbial colonization, increased surface roughness, and enhanced hydrophilicity through microbially mediated modification. High-throughput 16S rRNA sequencing unveiled a distinct community succession; PET exerted selective pressure that reduced alpha-diversity while enriching specific functional taxa such as Acinetobacter and Pseudomonas. Moreover, isolation and co-culture assays confirmed the importance of synergistic microbial interactions in PET transformation, with co-culture of four representative isolates causing 9.2 ± 0.1% PET weight loss, compared with only 1.7–3.2% in monocultures. These findings underscore the intrinsic natural attenuation potential of wetland ecosystems and provide a critical scientific basis for developing nature-based management strategies. By identifying key functional taxa and PET-associated transformation pathways, this work supports the establishment of early-warning mechanisms to safeguard the ecological integrity and soil health of coastal World Natural Heritage sites like the Tiaozini Wetland. Full article

The origin of life is, to the best of our knowledge, impossible to imagine without the formation of complex prebiotic biomolecules such as RNA, DNA, proteins and lipids. Lipids play a crucial role in the spontaneous formation of cell membranes, which are responsible for cell integrity, compartmentalization, selective permeability, and providing a microenvironment for biochemical reactions. The goal of the current work is to summarize the current state of the art regarding the abiotic formation of membrane building blocks, such as glycerol, fatty acids, and their phosphorylated version as phospholipid precursors. We describe the necessity of a systems chemistry approach for the complexification and expansion of the prebiotic network, enabling the formation of several membranogenic precursors. We also discuss prebiotic pathways for phosphorylation and acylation that could lead to phospholipid availability in hydrothermal environments and on the early Earth surface. We conclude with the possible spontaneous vesiculation of these molecules as a primitive version of the cell membrane. Thus, we present a comprehensive perspective on prebiotic vesicle formation, starting from simple molecules and developing until the self-assembly of vesicles. Full article