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PubMed2026

Enrichment of Lysobacter in a long-term organically managed agricultural field with low soilborne disease incidence.

Disease-suppressive soils, in which soilborne pathogens are naturally suppressed, offer a promising model for sustainable crop protection, particularly in organic farming systems where chemical disease control options are limited. Although disease suppression in these soils is considered to rely on biological control, the underlying mechanisms remain poorly understood. In this study, we investigated soil from a long-term organically managed field in Shiga Prefecture, Japan, where soilborne disease incidence has remained consistently low, to identify bacterial community features potentially associated with this field. The 16S rRNA gene amplicon sequencing indicated that this soil harbored a bacterial community distinct from those of nearby agricultural soils. Following the application of organic compounds, the genus Lysobacter, a taxon with known antagonistic activity against plant pathogens, was markedly enriched in response to proteinaceous organic inputs. This enrichment was consistent across sampling times and specific to certain proteinaceous organic inputs, whereas minimal effects were observed on chitin, N-acetyl-d-glucosamine, or cysteine. Broader soil surveys indicated that Lysobacter enrichment was not strictly associated with whether soils had been managed under organic or conventional farming practices. Stepwise multiple regression analysis identified 10 co-occurring bacterial genera that were strongly associated with Lysobacter abundance. These findings highlight condition-dependent Lysobacter enrichment as a characteristic microbial response to proteinaceous organic amendments in this low-disease-incidence field and provide microbial insights that may inform microbiome-based strategies for sustainable soil management.

Lysobacter↗

PubMed2026

Associations of red blood cell fatty acids with personality traits: 10-year follow-up in the Kibbutzim Family Study (KFS).

BACKGROUND: The ability of hostility and type-A personality to predict cardiovascular outcomes makes understanding antecedents of these personality traits an important public health objective. OBJECTIVES: This study aimed to examine whether blood-measured fatty acids (the exposure) are associated with hostility and type-A personality (the outcome), while accounting for lifestyle, sociodemographic factors, and polygenic background. METHODS: Personality traits, sociodemographic, and lifestyle data were obtained in 1992-1993 from 452 family members living in kibbutz settlements in Israel (visit 1) and remeasured 8 to 10 y later in 379 individuals (visit 2). Red blood cell (RBC) fatty acid concentrations were determined in visit 1 by gas chromatography. Longitudinal associations of visit 1 fatty acids with visit 2 personality traits were examined using linear models, before and after controlling for baseline personality scores. The contribution of environmental factors to personality scores beyond heritability was estimated by variance decomposition. RESULTS: In longitudinal analysis, 1% increase in visit 1 total n-6 (ω-6) fatty acid was associated with a 0.328-unit decrease in visit 2 type-A score [95% confidence interval (CI): -0.571, -0.085]. After adjustment for baseline personality levels, the association was slightly attenuated (β= -0.204; CI: -0.399, -0.009). One percent higher total n-6 was also associated with 1.119 units lower visit 2 hostility score (CI: -2.777, 0.038; P = 0.055). Finally, independent of the genetic contribution (32%-38% of adjusted variability in hostility and type-A personality), 1% increase in total n-3 and total n-6 was associated with 2.539 (CI: -3.907, -1.171) and 0.201 (CI: -0.365, -0.037) units lower hostility and type-A scores, respectively. CONCLUSIONS: Higher RBC total n-6 fatty acid concentrations are associated with lower type-A personality scores. After adjustment for baseline personality levels, the associations between total n-6 and hostility and between total n-3 and hostility are attenuated. These findings support further investigation of the relationship between fatty acid biology and personality traits using study designs better suited to causal inference.

Humans↗

PubMed2026

BIOCARD framework: integrating fecal bile acids, lipids, and metabolites to assess response to a cardiovascular health intervention.

Cardiovascular disease (CVD) remains a leading cause of morbidity and mortality, particularly in under-resourced populations. Although nutritional interventions are important for CVD prevention, their outcomes are commonly evaluated using conventional clinical and behavioral indicators, which may not fully capture early molecular responses. In this study, we developed the BIOCARD framework, an exploratory fecal multi-omics platform integrating bile acids, lipids, and metabolites to evaluate intervention outcomes related to cardiovascular health. Fecal samples were collected from caregiver-child participants enrolled in a 10-week randomized controlled trial comparing a multicomponent garden-based intervention (SHA) with an education-only control group (MSP). Fecal polar metabolites, lipids, and bile acids were analyzed by UHPLC-HRMS-based approaches and integrated with conventional health indicators. Traditional clinical indicators in the present study showed limited sensitivity for detecting intervention-related differences. In contrast, fecal multi-omics analyzes revealed intervention-associated differences in metabolites, lipids, and bile acids, with children showing more apparent molecular variation than parents. Network analysis further revealed associations between selected molecular features and cardiovascular-related indicators, including blood pressure, body fat, skin carotenoids, and Healthy Eating Index scores. Together, these findings suggest that the BIOCARD framework may serve as an exploratory molecular approach to complement traditional outcome measures and improve the evaluation of nutritional interventions for cardiovascular health.

Humans↗

PubMed2026

Metal-organic frameworks nanozyme-integrated portable microneedle patch for visual bacterial monitoring in meat.

Foodborne microbial contamination is a major global health concern, with conventional methods often being time-consuming and complex. Herein, we developed a novel portable biosensor by integrating microneedle patch technology and a metal-organic framework (Fe/Cu-NBDC MOF) nanozyme, enabling rapid, on-site, visual detection of bacteria in meat. The sensing system works by encapsulating aptamer-functionalized MOF nanozymes within a hydrogel patch, where their catalytic sites are initially blocked by the aptamer. In the presence of Staphylococcus aureus (S. aureus) as the target, the specific aptamer's binding to bacteria exposes numerous catalytic sites, further activating the chromogenic reaction of the tetramethylbenzidine‑hydrogen peroxide (TMB-H₂O₂) system, enabling visual detection of S. aureus. The biosensor demonstrates a detection limit of 82 CFU/mL with excellent specificity to successfully apply to commercial mutton. By integrating sampling, enrichment, and visual detection into a single compact device, this platform offers a practical, efficient solution for rapid on-site screening of foodborne pathogens.

Biosensing Techniques↗

PubMed2026

Bone progression in multiple myeloma: Benefit of zoledronic acid for patients achieving at least Very Good Partial Response and prognostic value of bone turnover markers.

The Magnolia study demonstrated that continuation of zoledronic acid (ZOL) beyond 2 years reduces the risk of progressive bone disease (PBD) in patients with multiple myeloma (MM). This follow-up study investigated the effects of ZOL in patients achieving very good partial response (VGPR) compared to patients who did not and whether bone turnover markers could identify patients at an increased risk of PBD following treatment cessation. Two Magnolia trial subgroups were analysed: patients with VGPR or better after 2 years of ZOL, randomized to either continued treatment or observation, and patients randomized to observation in whom serial bone markers (C-terminal cross-linked telopeptide of type I collagen [CTX], procollagen type I N-terminal propeptide [P1NP], bone-specific alkaline phosphatase [BAP], tartrate-resistant acid phosphatase isoform 5b [TRAcP]) were measured for up to 4 years. Continued monthly ZOL beyond 2 years significantly reduced the risk of PBD (hazard ratio 0.40; 95% confidence interval [CI] 0.16-0.92) in patients with VGPR or better (subgroup 1). After ZOL discontinuation, bone markers increased gradually. Elevated CTX (≥0.30 μg/L) and TRAcP (≥4 U/L) levels were associated with increased 6-month PBD risk (29% and 15% respectively) (subgroup 2). Continuation of ZOL beyond 2 years seems to reduce skeletal progression risk in patients achieving VGPR or better. Elevated CTX or TRAcP levels may help identify patients who could benefit from re-initiating ZOL.

Humans↗

PubMed2026

Evolutionary characterization and expression profiling of ACC and FASN genes in Chinese mitten crab Eriocheir sinensis.

Acetyl-CoA carboxylase (ACC) and fatty acid synthase (FASN) are rate-limiting enzymes in the fatty acid biosynthetic pathway, yet their evolutionary relationships, sequence features, and expression profiles remain poorly understood in crustaceans, particularly in the economically important Chinese mitten crab (Eriocheir sinensis). Here, we identified and systematically analyzed ACC and FASN genes in E. sinensis using comparative genomic analyses across 43 species. ACC was highly conserved as a single-copy gene in invertebrates, in contrast to the multiple paralogs observed in vertebrates. Similarly, FASN was generally maintained as a single-copy gene across most taxa but exhibited lineage-specific expansion in certain insect groups. Phylogenetic and structural analysis revealed strong conservation of both genes within crustaceans, supported by multiple conserved motifs and canonical functional domains. Expression profiling showed predominant expression in the hepatopancreas and midgut, suggesting their potential involvement in crustacean lipid metabolism. During the molting cycle, ACC and FASN exhibited higher expression levels during stages C and D, suggesting an increased capacity for fatty acid biosynthesis before molting. In addition, dietary lipid levels experiment revealed that ACC and FASN expression responded dynamically to dietary lipid availability, with increased expression at moderate lipid levels but reduced expression under excessive lipid supplementation, indicating a possible adaptive transcriptional response to lipid status. Collectively, this study provides insights into the evolutionary conservation and expression dynamics of ACC and FASN and improves our understanding of lipid metabolic adaptation in crustaceans.

Animals↗

PubMed2026

Bempedoic Acid and First and Recurrent Limb Outcomes in Statin-Intolerant Patients With Peripheral Artery Disease: Insights From the CLEAR Outcomes Trial.

BACKGROUND: Patients with peripheral artery disease (PAD) are at high risk of major adverse limb events (MALE) and major adverse cardiovascular events (MACE). Recently, bempedoic acid was shown to reduce MACE in primary and secondary prevention patients. Whether bempedoic acid reduces the risk of MALE in patients with PAD is unknown. METHODS: CLEAR Outcomes (Cholesterol Lowering via Bempedoic Acid [ETC1002], an ACL-Inhibiting Regimen) randomized 13 970 patients to bempedoic acid 180 mg or placebo from December 22, 2016, to August 14, 2019. The trial primary end point was MACE-4, defined as death resulting from cardiovascular causes, nonfatal myocardial infarction, nonfatal stroke, or coronary revascularization. A clinical history of PAD was reported by investigators at baseline. Two blinded vascular medicine specialists independently adjudicated MALE, including adverse events indicating worsening PAD symptoms leading to revascularization, chronic limb-threatening ischemia, and acute limb ischemia. Outcomes were assessed as time to first event and total (including recurrent) events with a negative binomial approach. RESULTS: A total of 1624 of the enrolled patients (mean±SD age, 63.9±9.9 years; 915 [56.3%] female) had PAD at baseline. In patients with PAD in the placebo group, 69 (8.3%) had MALE over a median of 40.6 months, with rate of recurrent events of 4.0%/y. Bempedoic acid reduced the risk of MALE by 36% (hazard ratio, 0.64 [95% CI, 0.44-0.93]; P=0.018). Bempedoic acid reduced total MALE by 45% (relative risk, 0.55 [95% CI, 0.35-0.85]; P=0.007). First MACE-4 or MALE was reduced overall by 13% (hazard ratio, 0.87 [95% CI, 0.80-0.95]) with consistent effects with PAD (hazard ratio, 0.82 [95% CI, 0.64-1.04]) and without PAD (hazard ratio, 0.87 [95% CI, 0.79-0.86]; Pinteraction=NS) but not statistically significant within the PAD subgroup alone. Total MACE-4 or MALE was reduced (relative risk, 0.81 [95% CI, 0.73-0.90]) overall with consistent effects in PAD (relative risk, 0.71 [95% CI, 0.54-0.95]) and without PAD (relative risk, 0.82 [95% CI, 0.73-0.92]; Pinteraction=NS). CONCLUSIONS: Patients with PAD are at high risk of MALE and MACE. Bempedoic acid reduces both MACE and MALE in patients with atherosclerotic vascular disease, with notable absolute benefits in patients with PAD. These findings support (1) the importance of lowering low-density lipoprotein cholesterol in patients with PAD to reduce overall vascular risk and (2) the benefits of bempedoic acid in this population.

Humans↗

PubMed2026

Prophylactic folinic acid prevents pemetrexed myelosuppression: A randomized trial toward safer treatment with chemotherapy in non-small cell lung cancer.

Background Pemetrexed is a cornerstone in advanced non-small cell lung cancer treatment. Although generally well tolerated, severe myelosuppression occurs in 26% of patients. Preventing chemotherapy-associated toxicity has become increasingly important with the introduction of osimertinib combined with pemetrexed-based chemotherapy. Due to substantial toxicity, this regimen is often not administered to frail patients. Folinic acid prophylaxis can mitigate pemetrexed-induced toxicity, however its preventive use has not been routinely studied. We aimed to investigate the efficacy of folinic acid prophylaxis to reduce myelosuppression. Methods Fifty patients treated with pemetrexed were randomized (1:1) to receive pemetrexed with or without oral folinic acid prophylaxis on days 2-4 after each chemotherapy cycle. The primary endpoint was absolute neutrophil count (ANC) after the first chemotherapy cycle. Secondary endpoints included ANC after the second cycle, grade neutropenia, treatment efficacy, renal function and incidence of dose modifications. Results Twenty-four patients received folinic acid and twenty-six served as controls. Higher ANC were observed in the folinic acid group after the first cycle (median 3.79; IQR 2.22-4.93 vs. 1.85; IQR 1.43-3.78; p.

Humans↗

PubMed2026

Efficacy and safety of split-dose ultra-low-volume polyethylene glycol with ascorbic acid versus sodium picosulfate with magnesium citrate for bowel preparation: a systematic review and meta-analysis.

Colonoscopy remains the gold standard for early detection and prevention of colorectal cancer, with adequate bowel cleansing being pivotal for its success. This systematic review aims to evaluate the efficacy and safety of split-dose ultra-low-volume polyethylene glycol (PEG) with ascorbic acid (Asc) versus sodium picosulfate magnesium citrate for bowel preparation. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we conducted a comprehensive literature search across Embase, PubMed, Web of Science, and Scopus from inception to July 2025. Data analysis was conducted using R version 4.2.2 (31 October 2022) and RStudio version 2022.07.2 (2009-2022, RStudio, Inc.) Our literature search yielded six eligible studies involving 3285 patients. Our findings indicate no significant differences in overall and right-sided colon adequate cleansing rates between the two regimens: risk ratio: 1.05, 95% confidence interval (CI): 0.99-1.12, P  = 0.1082; and risk ratio: 1.03, 95% CI: 0.99-1.08, P  = 0.1755, respectively. However, PEG + Asc demonstrated a significantly lower rate of vomiting compared to sodium picosulfate magnesium citrate (risk ratio: 2.58, 95% CI: 0.94-2.78, P  = 0.0008), suggesting better tolerability. Other secondary outcomes, including nausea, abdominal pain, and overall Boston Bowel Preparation Scale scores, did not show significant differences. The quality of the evidence varied across the outcomes. Our results support the comparable efficacy of both bowel preparation agents while highlighting PEG + Asc's potential advantages in tolerability. Our findings suggest that the choice between these two preparations can be tailored to the specific patient, considering their preferences or previous experiences, although some caution is advised in interpreting these findings.

Humans↗

PubMed2026

Vegan multinutrient supplementation significantly increases Omega-3 index and 25-OH-vitamin D status: a randomized, double-blind, placebo-controlled trial in healthy young vegans.

In this randomized, double-blind, placebo-controlled trial, 72 healthy vegan adults (aged 19-57 years) received a multinutrient supplement consisting of a vitamin and mineral supplement (providing 26 µg vitamin D) and an omega-3 supplement administered in either a single dose (EPA 98.7 mg, DHA 171.0 mg, additional vitamin D 36 µg, vitamin E 3.7 mg) or a double dose (EPA 197.4 mg, DHA 342.0 mg, additional vitamin D 72 µg, vitamin E 7.4 mg) or placebo capsules for 4 months. Nutrient biomarkers were assessed at baseline and at the end of the intervention after 4 months. An analysis of covariance was employed to test for between-group differences (p < 0.05) and adjusted for multiple testing using the Bonferroni-Holm method. Compared to the control group, which showed on average a significant decline in both the omega-3-index and 25-hydroxyvitamin D, participants in both intervention groups demonstrated significant increase in these parameters (p < 0.001). Although the double dose group exhibited numerically greater increases in omega-3 index and vitamin D compared to the simple dose group, the differences between these dosing regimens were not statistically significant. As expected, vitamin E levels remained unchanged, reflecting its inclusion solely for antioxidative protection in the omega-3 supplement rather than as a critical nutrient in vegan diets. In conclusion, supplementation significantly improved omega-3 and vitamin D status in healthy vegans, with no significant benefit from doubling the dose. Although clinical endpoints were not evaluated, improved nutrient status may have potential implications for health. The study has been registered at the German Clinical Trials Register (DRKS00028151).

Humans↗

PubMed2026

Proteomic insights into hepatic responses to high soybean meal inclusion with citric acid supplementation in hybrid grouper (Epinephelus fuscoguttatus × Epinephelus lanceolatus) juveniles.

This study evaluated the growth performance and hepatic proteomic responses of juvenile hybrid grouper (Epinephelus fuscoguttatus × Epinephelus lanceolatus) juveniles fed diets containing 30% or 40% soybean meal (SBM), with or without 3% citric acid supplementation, and compared with a fishmeal (FM) control diet over a 10-week feeding trial. Fish fed 30% SBM (LSBM) showed a final body weight comparable to the FM group, whereas fish fed 40% SBM (HSBM) recorded significantly reduced growth and net protein utilization (NPU) (p < 0.05). Supplementation of citric acid in the 40% SBM diet (HSBM + CA) significantly improved NPU and partially restored growth relative to HSBM. LC-MS/MS based quantitative proteomics identified 1544 hepatic proteins and showed clear dietary segregation. Differentially expressed proteins were predominantly associated with reduced abundance of proteins involved in lipid metabolism, amino acid metabolism, pyruvate metabolism, and the tricarboxylic cycle across all SBM diets, suggesting a shift in oxidative metabolic capacity. In contrast, LSBM induced upregulation of spliceosome-associated proteins and RNA processing components, suggesting adaptive post-transcriptional regulation under moderate SBM inclusion. In contrast, HSBM exhibited greater reduction in metabolic protein abundance without comparable upregulation of adaptive regulatory components, coinciding with reduced nutrient retention. Protein-protein interaction analysis further confirms the correlation between the regulation of spliceosomal clusters and mitochondrial lipid-catabolic modules. Citric acid supplementation did not markedly reverse hepatic metabolic protein changes but improved protein retention. Data are available via ProteomeXchange with identifier PXD081994. These findings suggest a tolerance limit between 30% and 40% SBM inclusion, with 30% inducing adaptive hepatic proteomic responses compatible with maintained growth performance.

Animals↗

PubMed2025

UV-based homogeneous disinfection process for removal of antibiotic resistance genes: Efficiency, mechanisms and influencing factors.

The proliferation and dissemination of antibiotic resistance genes (ARGs) in aquatic environments pose a serious threat to global public health. Ultraviolet-driven homogeneous advanced oxidation processes (UV-AOPs) represent a prospective suite of technologies for the efficient removal of ARGs. This review critically assesses recent advances in the application of UV-AOPs, specifically UV/hydrogen peroxide (UV/H2O2), UV/peracetic acid (UV/PAA), UV/persulfate (UV/PS), and UV/chlorine (UV/Cl), for the elimination of extracellular ARGs and intracellular ARGs. The underlying mechanisms involve direct ultraviolet-induced DNA damage, including pyrimidine dimer formation and strand breakage, as well as oxidation mediated by radicals such as hydroxyl radicals, sulfate radicals, carbon-centered radicals, and reactive chlorine species. The relative contribution of radical and non-radical pathways is strongly influenced by water chemistry and process conditions. We further expound on the critical operational and environmental factors governing ARG removal kinetics, including UV wavelength and fluence, oxidant type and dosage, ARG sequence characteristics, pH, ubiquitous anions, and dissolved organic matter, which collectively affect radical generation, quenching, and reaction microenvironments. Notably, for i-ARGs, UV-AOPs facilitate degradation not only through direct radical attack but also by disrupting cellular integrity and permeabilizing membranes, thereby enhancing the exposure of genetic materials to oxidative and photolytic damage. This review synthesizes current understanding to provide a mechanistic basis for the design and optimization of UV-AOP systems, highlighting their potential as effective barriers against the dissemination of antibiotic resistance in water reuse and purification scenarios.

Disinfection↗

PubMed2026

Ecological Restoration of the Soil-Like Function in the Bauxite Residue: Natural Microbiomes Mediated Molecular Transformation of Dissolved Organic Matter.

Soilization of bauxite residues offers a scalable route for long-term carbon management and ecological restoration. However, the microbial processes that transform exogenous organic inputs into stable soil-like carbon pools remain poorly resolved. Here, we combined cross-ecosystem meta-analysis, machine-learning prediction, native synthetic community (SynCom) construction, 13C-labeled straw microcosms, field validation, Fourier transform ion cyclotron resonance mass spectrometry, and genome-resolved metagenomics to unravel microbiome-mediated carbon transformation at the dissolved organic matter (DOM) molecular scale. Our meta-analysis revealed that alkaline industrial wastes retained soil-like DOM signatures but were enriched in microbial humic- and protein-like components, indicating active yet incomplete carbon processing. Guided by these patterns, native SynCom inoculation increased 13C incorporation into total organic carbon (TOC) and dissolved organic carbon (DOC), enlarged biodegradable and adsorbable DOC fractions, and shifted DOM from recalcitrant aromatic pools toward oxygenated carbohydrate-, tannin-, and phenolic-like molecular classes. Genome-resolved analyses linked this transformation to complementary polymer degradation and nutrient-cycling functions across fungal and bacterial guilds, including enriched carbohydrate-active enzymes in straw-carbon-utilizing metagenome-assembled genomes. Null model and thermodynamic analyses further showed that microbial communities were constrained by homogeneous selection, whereas DOM molecules were diversified through variable selection and redox-dependent transformation. Field-scale validation confirmed that SynCom promoted TOC and DOC accumulation and humic-like, high-density DOM fractions under alkaline conditions. Together, these findings establish a mechanistic framework in which functional microbiomes couple plant carbon depolymerization, DOM molecular diversification, and mineral-interactive carbon stabilization, providing a microbiome-guided strategy for carbon sequestration and soilization in the bauxite residue.

Soil↗

PubMed2026

Nitrogen sources and concentrations shape algal odor compounds: Key drivers of β-cyclocitral and β-ionone in water bodies of the lower Yangtze River.

Taste and odor (T&O) compounds derived from cyanobacterial blooms pose escalating threats to freshwater security worldwide, yet the drivers of specific T&O metabolites remain poorly constrained. Here, we investigated the dual effects of nitrogen (N) sources and concentrations on the production of β-cyclocitral and β-ionone, two algal-derived T&O compounds, through integrated field surveys (54 sites across lakes and rivers) in the eutrophic lower Yangtze River, China, and laboratory cultivation of typical cyanobacteria (Microcystis aeruginosa and Pseudanabaena cinerea). Our field data revealed that the concentrations of β-cyclocitral and β-ionone in lakes and rivers were not significantly different, but increased with the trophic level index. Redundancy analysis and Mantel analysis showed that Microcystis and Pseudanabaena were potentially dominant contributors to β-cyclocitral and β-ionone in the water column. Structural equation modeling and variation partitioning analysis showed that enhanced nitrate (NO3--N) significantly promoted the production of these compounds. Laboratory experiments demonstrated that inorganic N (NaNO₃) maximized total T&O yields by promoting algal biomass, whereas organic N (urea and glutamic acid) elevated the T&O production per unit biomass by 1.5- to 9.5-fold. Notably, Pseudanabaena exhibited a 2.3-fold higher β-ionone yield than Microcystis, with greater sensitivity to N concentrations. Our study highlights the critical role of nitrogen pollution, both source and concentration, in the production of T&O compounds by phytoplankton and provides reference data for managing T&O issues in rivers and shallow lakes.

Norisoprenoids↗

PubMed2025

Coupling of spectroscopy and nitrogen-oxygen isotopes unveils the mechanisms of dissolved organic matter and nitrate pollution in lakes within the agro-pastoral transition zone.

Lakes in arid and semi-arid regions are subjected to severe ecological stress, such as organic pollution, eutrophication, and salinization, due to climate change and human activities. This study investigates Chagannur Lake, a typical arid-region lake that is representative and ecologically sensitive in Northern China's agro-pastoral ecotone, to uncover its pollution characteristics and mechanisms. We employed fluorescence spectroscopy and stable isotope analysis to trace dissolved organic matter (DOM) and nitrate sources. The DOM composition was dominated by microbial metabolic byproducts and protein-like substances, suggesting that microbial processes are key to organic matter transformation. Source apportionment revealed that pollutants primarily originated from livestock and poultry manure (37.6 %), agricultural fertilizers (35.6 %), and soil erosion (24.7 %), with agricultural fertilizers contributing most significantly in the Gogstai River (63.3 %). A structural equation model (SEM) coupling spectral and mass spectrometric data revealed that microbial transformation significantly impairs the lake's self-purification capacity, thereby promoting pollutant accumulation (path coefficient = 0.91,*p < 0.05). Moreover, microbial processes link endogenous and exogenous pollution, a mechanism effectively traced by isotopic and fluorescence indices (path coefficient = 0.55, ⁎⁎p < 0.01). These findings enhance the understanding of pollution sources and transformation mechanisms in arid-region lakes and offer foundational theoretical support for policymakers engaged in pollution control strategies.

Lakes↗

PubMed2026

Multiomic insights into fungal polylactic acid degradation: Metabolic adaptation and hydrolytic mechanisms of Sporobolomyces pararoseus.

Polylactic acid (PLA), a biodegradable polyester from renewable resources, is a sustainable alternative to petrochemical plastics. However, its environmental degradation is inefficient naturally, requiring specific microbial activities. While bacterial PLA-degrading mechanisms are well documented, fungal degrading systems-particularly their molecular mechanisms-are underexplored.We isolated Sporobolomyces pararoseus ZRQ01 from the gut microbiota of PLA-fed mealworms. This fungal strain noticeably degraded PLA in PLA-containing medium supplemented with 2% glucose. Biodegradation assays revealed 22.8% loss of the PLA film weight after 35 days of incubation, and scanning electron microscopy confirmed extensive surface erosion and pore formation. Integrated transcriptomic and proteomic analyses, together with the reference genome of S. pararoseus ZRQ01, revealed that S. pararoseus ZRQ01 upregulates hydrolytic enzymes at both transcript and protein levels to cleave PLA into lactic acid. After lactic acid is transferred into S. pararoseus ZRQ01 cells by monocarboxylate transporters with increased abundance, it is assimilated by pathways of pyruvate metabolism and the TCA cycle with increased protein abundance. Intriguingly, upregulation of genes in autophagy-related and MAPK signaling pathways underscores an adaptive stress response potentially supporting cellular homeostasis and degradation-related gene expression. Our results highlight S. pararoseus ZRQ01's metabolic potential for bioremediation and offer insights into fungal bioplastic degradation pathways.

Polyesters↗

PubMed2026

Comprehensive identification of carboxylic acids by using bromine isotope-based chemical isotope labelling and structure-guided molecular network.

Carboxylic acids (CAs) are important contributors to the flavor quality of sauce-flavor Chinese Baijiu, yet their comprehensive analysis remains challenging due to poor ionization efficiency, weak chromatographic retention, and limited annotation capability. Herein, we developed a workflow for the high-coverage discovery and annotation of CAs in Baijiu by coupling chemical isotope labeling-liquid chromatography-mass spectrometry with a structure-guided molecular network strategy (SGMNS). A bromine-containing derivatization reagent, 1-(3-aminopropyl)-3-bromoquinolin-1-ium bromide (APBQ), was designed and synthesized to exploit the natural isotope distribution of bromine and characteristic MS/MS fragmentation behavior. Following APBQ derivatization, the target CAs showed superior chromatographic retention and favorable analytical performance. Based on isotopic peak pairing in MS1 and diagnostic fragment validation in MS2, 372 potential CA derivatives were discovered from pooled Baijiu samples and 355 of them were validated by diagnostic fragments in MS2 spectra. To address the scarcity of derivatized spectral libraries, SGMNS was employed for annotation using a background network constructed from APBQ-labeled candidates derived from the Expanded Chinese Baijiu Compound Database. The developed method was further applied to profile Baijiu samples, revealing pronounced differences in CA composition across the seven fermentation rounds. Notably, rounds 3 to 5 exhibited the largest numbers of differential CAs. This study provided an effective analytical strategy for large-scale CA profiling, offering new insight into the chemical basis of flavor formation during multi-round fermentation of sauce-flavor Baijiu.

Isotope Labeling↗

PubMed2025

Effects of aerosol aging on composition and light-absorbance of nitrogen-containing organic compounds: Evidences from ultra-high-resolution mass spectrometry analysis.

Nitrogen-containing organic compounds (NOCs) are key components of particulate matter (PM), but their compositional evolution and light-absorbing properties during atmospheric aging remain poorly understood. In this study, ultra-high-performance liquid chromatography coupled with Orbitrap mass spectrometry was used to semi-quantitatively analyze 59 PM1 samples collected in Shanghai. NOCs accounted for 31 % and 64 % of the detected species in negative (ESI-) and positive (ESI+) ionization modes, respectively. Atmospheric aging significantly reduced the molecular diversity of polar organics, with both the number and mass concentration percentages of CHON- compounds showing significant negative correlations with aging degree. Van Krevelen analysis demonstrated a decrease in the number of carboxylic-rich alicyclic molecules and their CHON- contributions during the aging process (from 37.7 % in fresh samples to 21.2 % in aged samples). CHN+ compounds, a major NOCs group in ESI+ mode, also decreased with aging. Correlation analyses involving the Bep/(Bep+Bap) ratio, relative humidity, and mass absorption efficiency at 365 nm revealed a decline in light absorption capacity with aging, suggesting aqueous-phase oxidation as a dominant aging mechanism. CHON- and CHN+ compounds were identified as the principal light-absorbing constituents in PM1. This work provides new insights into the aging-induced transformations of NOCs in urban PM1, and their changing role in light absorption, highlighting the need for further investigation of the aging mechanisms of NOCs.

Aerosols↗