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Optimizing eco-engineering pedogenesis of bauxite residues: Synergistic effects of humus and FeSO4/sulfur on microbial community and function.

Eco-engineered pedogenesis represents a promising approach for soil amelioration of bauxite residues (BRs) through exogenous organic matter. However, the role of humus in mediating this process remains poorly understood, significantly impeding the eco-engineering rehabilitation of BRs. In this study, we conducted pot experiments and subsequent microbial analysis to evaluate the individual improvement of humic acid (HA), fulvic acid (FA), and corn straw (SWZ) on the BRs' pedogenesis. High-throughput sequencing analysis revealed that both FA and SWZ were more effective than HA in steering microbial community assembly, as community diversity, dominant taxa enrichment, and species' interaction were all significantly higher (p < 0.05) in the FA/SWZ treatments than in HA treatments. Notably, the combination of FA with FeSO4 specifically enriched halophilic taxa, while FA coupled with sulfur (S) significantly improved the connectivity and complexity of the microbial network, as the average connection degree increasing from 1.008 to 1.113. Hydrolytic enzyme activity assays further indicated that FA, especially when combined with S, was the most effective treatment in restoring microbial function during BR pedogenesis. These findings highlight FA as a critical driver of microbial restructuring and functional recovery in BRs. Moreover, its efficacy can be enhanced by co-amendment with FeSO4 or S. This study provides important theoretical and practical insights for optimizing organic-inorganic amendment strategies to accelerate the eco-engineering pedogenesis of bauxite residues.

Humic Substances

Single-cell transcriptomics reveals heterogeneous stress responses and Mg2+-mediated survival mechanisms in Lactobacillus delbrueckii subsp. bulgaricus during freeze-drying and storage.

Maintaining the viability of lactic acid bacteria during dehydration and subsequent storage remains a significant challenge. Here, we employed single-cell RNA sequencing to reveal the heterogeneous stress responses of Lactobacillus delbrueckii subsp. bulgaricus, identifying seven distinct transcriptional clusters across the liquid culture, freeze-drying, and storage phases. The dominant clusters in the freeze-drying and storage were not completely consistent, showing significant functional differentiation. Genomic stability may be important for survival during freeze-drying and storage, while intracellular energy homeostasis appears important for viability during storage. The magnesium transporter mgtB was highly expressed in clusters tolerant to freeze-drying and storage, suggesting a critical role for Mg2+ homeostasis. Further experimental validation confirmed that Mg2+ treatment significantly bolstered stress resistance, increasing immediate post-freeze-drying survival by over 2-fold (up to 92.90%) and post-storage survival by over 5-fold (up to 5.98%). Proteomic data indicated that Mg2+ supplementation correlated with the maintenance of several biological functions potentially relevant to bacterial survival during freeze-drying and storage, including DNA repair, translation, and central carbon metabolism. These findings provide a map of microbial stress resistance through population heterogeneity and offer a potential strategy that may be adapted for enhancing the stability of other industrial lactic acid bacteria products.

Freeze Drying

Protein profiling and GC-MS product analysis provide insights into lignite solubilization and bioconversion by Lysinibacillus sphaericus strain SH19.

Lignite biosolubilization offers a mild route for valorizing low-rank coal, although the microbial processes that accompany solubilization remain incompletely defined. Here, an endogenous isolate designated Lysinibacillus sphaericus strain SH19 was evaluated using nitric-acid-pretreated Shengli lignite. Under the selected working conditions (4 M nitric-acid pretreatment, initial pH 8, 40&#xb0;C, and 16 days), the apparent solubilization rate reached 66.81%. Changes in A450, residual solid mass, culture pH, and extracellular protein concentration showed that chemical pretreatment and bacterial culture were both associated with the release of soluble lignite-derived material. SDS-PAGE and two-dimensional electrophoresis revealed treatment-associated differences in extracellular and intracellular protein patterns. LC-MS/MS analysis of excised protein spots yielded 85 candidate protein assignments; the revised supplementary table reports PEAKS scores, sequence coverage, peak area, and unique-peptide counts and highlights the limited support for several entries. GC-MS analysis produced 33 tentative library assignments in the solubilized fraction, but siloxane- and silyl-related signals were treated as possible analytical background, and no pathway was inferred from these assignments alone. Together, the data identify strain SH19 as a promising lignite-biosolubilizing isolate and provide candidate proteins and product signals for future validation. The proposed process model remains exploratory because direct enzyme assays, inhibitor experiments, carbon-balance measurements, transcriptomic or genetic validation, complete GC-MS blank subtraction, and authentic-standard confirmation were not available.

Bacillaceae

Desert-derived Ensifer sp. SA403 enhances potato salt tolerance by reshaping rhizosphere microbiome functions and host responses.

Soil salinization increasingly threatens global food security, and potato (Solanum tuberosum L.), a moderately salt-sensitive crop, is particularly vulnerable to saline soils. Plant growth-promoting rhizobacteria (PGPR) offer a promising strategy to improve crop performance, yet how PGPR interact with native microorganisms to enhance potato salt tolerance remains poorly understood. In this study, we identified a desert-derived PGPR strain, Ensifer sp. SA403, which substantially enhanced potato performance under high salinity across sterile, non-sterile and field conditions. Physiologically, inoculation with SA403 reduced shoot Na&#x207a; accumulation and increased the K&#x207a;/Na&#x207a; ratio; notably, these effects were markedly stronger in non-sterile substrates than under sterile conditions, indicating that SA403-mediated ion homeostasis relies on cooperation with the resident microbiota rather than on the strain acting alone. Metagenomic profiling indicated that SA403 strain reshaped rhizosphere communities, significantly enriching beneficial taxa such as Priestia and Bradyrhizobium, and upregulated functional pathways involved in glutathione and sulfur metabolism. Furthermore, host transcriptomic analyses showed that SA403 modulated plant responses to salt stress, with differentially expressed genes enriched in jasmonic acid signaling, ethanolamine metabolism and amino-acid biosynthesis pathways. Field trials on saline soils confirmed that SA403 significantly increased seedling emergence and tuber weight. Together, our results demonstrate that SA403 functions as a biological mediator that optimizes rhizosphere microecology and coordinates ion balance and host signaling to enhance potato salt tolerance. These findings support the potential of SA403 as a robust PGPR-based tool for sustainable potato production on saline soils.

Rhizosphere

Enhancement of secondary organic aerosol formation from isoprene photooxidation by ammonia.

Ammonia (NH3) can participate in atmospheric secondary organic aerosol (SOA) formation by reacting with organic acids and carbonyl compounds in particle phase, but its influence on the gas phase chemistry remains unclear. This study performed a series of smog chamber experiments to investigate the influence of NH3 on the formation of SOA from isoprene photooxidation by OH radicals. Both gas and particle phase products were measured with a series of state-of- art instruments including a nitrate ion chemical ionization mass spectrometer (nitrate-CIMS) and high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS). Our results showed that in the presence of NH3 SOA in the chamber significantly increased, along with an enhanced oxidation of isoprene. CIMS analysis further showed that NH3 in the chamber homogeneously reacts not only with gas-phase organic acids but also with gaseous low volatility oxygenated organic molecules (OOMs) to generate extremely low volatility and ultralow volatility NH3-OOMs clusters. Quantum chemical calculation showed that NH3 can spontaneously interact with OOMs to form NH3-OOMs clusters by forming hydrogen bonds with RCOOH, R-OOH, and R-OH. These clusters can promote new particles formation and particle growth through nucleation and condensation, directly enhancing the isoprene SOA production with a contribution of 78% to the enhanced SOA. Moreover, the formation of NH3-OOMs clusters also results in more isoprene consumed by OH radicals, indirectly increasing the SOA production with a contribution of 22 % to the enhanced SOA. Our work for the first time clarified a synergetic effect of NH3 on isoprene SOA formation, which should be accounted for by models.

Aerosols

Integrative machine learning and transcriptomic analysis reveals molecular mechanisms underlying low survival rate in larval Chinese Bahaba (Bahaba taipingensis).

Chinese Bahaba (Bahaba taipingensis) is a Class I protected marine fish endemic to China. Low larvae survival during artificial breeding severely hinder population recovery. To investigate the molecular mechanism of high mortality in larval fish, this study performed RNA-seq on liver from naturally deceased (ND) and mass-dead (MD) individuals, combined with least absolute shrinkage and selection operator (LASSO) regression and random forest (RF) algorithms to screen for core signature genes. A total of 873 differentially expressed genes (DEGs) were identified, including 112 upregulated and 761 downregulated genes. GO and KEGG enrichment analyses revealed significant enrichment in amino acid metabolism disorders, one&#x2011;carbon folate pool impairment, PPAR signaling abnormalities, ECM-receptor interaction, focal adhesion pathway, indicating widespread metabolic suppression accompanied by extracellular matrix remodeling and signaling disturbances in the livers of MD fish. MAD pre-filtering combined with dual machine learning algorithms yielded 18 robust core signature genes, among which SLC38A4, MMP1, FADD, FKBP5, and APOB were consistently identified as high-frequency core genes by both algorithms. SLC38A4 exhibited the highest importance score in the RF model and was significantly downregulated, making it the primary molecule distinguishing ND from MD phenotypes. ROC curve analysis showed that both models achieved an AUC of 1.000 (95% CI lower bound: 0.610), confirming the precise discriminatory ability of the core genes. GSEA further demonstrated significant enrichment of this core gene set in ND samples. This study provides the first systematic elucidation of the molecular mechanisms underlying liver dysfunction in low survival rate B. taipingensis, characterized by amino acid transport impairment, metabolic reprogramming, and structural remodeling, offering theoretical foundations for health assessment, early mortality risk warning, and artificial breeding conservation of this species.

Animals

Metabolomic and structural signatures of pigmented and non-pigmented Himalayan rice landraces.

BACKGROUND: This study investigated the anti-oxidant properties, starch composition, pasting behavior, structural properties, textural properties and non-targeted metabolomic profiles of pigmented and non-pigmented rice landraces as potential next-generation functional food ingredients. RESULTS: Pigmented rice demonstrated 1.34 times more anti-oxidant activity as compared to non-pigmented rice. Pigmented landraces showcased superior nutritional and functional attributes, including higher total dietary fiber and starch content. Fourier-transform infrared (FTIR) analysis revealed distinct molecular signatures with enhanced peak transmittance, while X-ray diffraction (XRD) indicated greater crystallinity ranging from 36-44.3% in pigmented rice compared with 30-40% in non-pigmented rice, suggesting improved digestibility and processing versatility. Pigmented rice recorded less amylose content hence tended to possess increased adhesiveness values whereas non-pigmented rice revealed greater amylose content hence was coupled with greater hardness values. Field-emission scanning electron microscopy (FE-SEM) images revealed that pigmented rice had densely packed and polygonal starch granules whereas non-pigmented rice had loosely packed starch granules with intergranular voids. Untargeted gas chromatography-mass spectrometry (GC-MS) profiling identified 84 metabolites, including unique compounds such as 3,3-dimethylbutanol and ethanoic acid, along with shared metabolites such as sucrose and linoleic acid, highlighting notable biochemical diversity. Multivariate statistical analyses using principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway mapping further differentiated the metabolomic landscapes, with variable importance in the projection (VIP) scores identifying key bioactive contributors. CONCLUSION: Pigmented rice landraces exhibited significant functional and nutritional advantages, making them promising candidates for functional food development and nutritional improvement programs. These findings support their potential role in advancing sustainable and health-oriented food systems. &#xa9; 2026 Society of Chemical Industry.

Oryza

Physiological and molecular responses of coelomocytes to low- to mid-frequency acoustic exposure in the sea urchin Strongylocentrotus intermedius.

Underwater noise is a widespread environmental pollutant in marine ecosystems, yet the effects of low- to mid-frequency acoustic exposure on immune physiology and molecular responses in echinoderms remain unclear. In this study, the sea urchin Strongylocentrotus intermedius was exposed to continuous pure-tone acoustic stimulation at 80, 125, 250, 500, 750, and 1000&#xa0;Hz for 3&#xa0;h. Results showed that acoustic exposure significantly affected redox homeostasis, energy metabolism, and immune function in S. intermedius coelomocytes: the antioxidant system and glutathione redox balance were altered, as indicated by increased superoxide dismutase (SOD) and catalase (CAT) activities, elevated reduced glutathione (GSH) content, and a higher GSH/GSSG ratio; glycolysis-related enzyme activities were enhanced, with increased pyruvate kinase (PK) activity under 125-500&#xa0;Hz exposure and elevated hexokinase (HK) activity at 250&#xa0;Hz; and immune function was impaired, as shown by increased coelomocyte mortality, reduced phagocytic activity, and inhibited acid phosphatase (ACP) and alkaline phosphatase (AKP) activities, whereas respiratory burst activity showed no significant change. Among all treatments, 250&#xa0;Hz induced the most pronounced physiological responses. Transcriptomic analysis of coelomocytes from the 250&#xa0;Hz group identified 663 differentially expressed genes, including 537 upregulated and 126 downregulated genes, mainly enriched in pathways related to apoptosis, phagosome, lysosome, glutathione metabolism, arachidonic acid metabolism, and carbohydrate metabolism. These findings indicate that low- to mid-frequency acoustic exposure can act as a physiological and molecular stressor to S. intermedius coelomocytes by affecting redox homeostasis, enhancing energy metabolism, and suppressing immune effector processes, with 250&#xa0;Hz showing the strongest effect under the present exposure conditions. This study provides experimental evidence for evaluating the potential biological effects of low- to mid-frequency acoustic exposure on benthic echinoderms.

Animals

Alginate-based edible coating incorporating green tea extract for preserving postharvest quality and safety of white mushrooms (Agaricus bisporus).

This study aimed to evaluate the effects of a sodium alginate based edible coating incorporated with green tea extract (GTE) (Camellia sinensis) on the postharvest quality attributes and antimicrobial activity against Listeria monocytogenes in white mushrooms during refrigerated storage. The phenolic profile of GTE was characterized, and its minimum inhibitory concentration (MIC) against L. monocytogenes (1.6&#xa0;mg/mL) was determined. Sodium alginate coatings, with (ALG-GTE) or without GTE (ALG) at MIC (1.6&#xa0;mg/mL), were characterized (functional groups, solubility in water, moisture, thickness, water contact angle and color) for their chemical and physical properties. The effects of ALG-GTE coatings on quality parameters (firmness, weight loss, color, pH, sugars and organic acids), enzymatic activity [polyphenol oxidase (PPO), peroxidase (POD) and pectin methylesterase (PME)], antimicrobial activity against L. monocytogenes (5 log CFU/g), and surface characteristics (3D optical profilometry) were assessed in white mushrooms (Agaricus bisporus) during refrigerated storage (8&#xa0;days, 4&#xa0;&#xb1;&#xa0;1&#xa0;&#xb0;C, 90-95% RH). The ALG-GTE coatings preserved sugar composition, particularly rhamnose, reduced organic acids accumulation and delayed weight and firmness loss, reduced color changes, and decreased PME activity in coated white mushrooms. L. monocytogenes counts decreased by 1.4 log CFU/g after 1&#xa0;day, and no viable cells were detected after 2&#xa0;days (< 1.5 log CFU/g) in ALG-GTE coated white mushrooms. In addition, ALG-GTE coated white mushrooms exhibited smoother surfaces than uncoated samples. These findings highlight the potential of ALG-GTE coatings as a sustainable alternative capable of improving the microbiological safety and delaying the postharvest changes in fresh mushrooms.

Agaricus

Multi-omics reveal microbial functional traits and antifungal metabolites associated with lower Pseudogymnoascus destructans loads in bat cave soils.

White-nose syndrome, caused by Pseudogymnoascus destructans (Pd), is a major fungal disease threatening hibernating bats. Cave soils can serve as environmental reservoirs for Pd, yet the microbial and biochemical mechanisms underlying naturally low Pd burdens in some cave environments remain poorly understood. Here, we integrated soil microbiome profiling, metagenomics, metabolomics, multi-omics network analysis, and in vitro validation to investigate the ecological and functional basis of differential Pd loads in hibernating bat caves in Northeast China. The three caves shared cold, humid, and weakly acidic microenvironments, but differed significantly in electrical conductivity, soil water content, nutrient availability, and extracellular enzyme activities. Soil microbial communities showed significant inter-cave variation in composition, diversity, and niche breadth, with stochastic processes contributing substantially to community assembly. Environmental variables, particularly pH and Pd load, were important predictors of microbial community structure. Functional analyses revealed that the low-Pd Gezi Cave was enriched in genes associated with organic carbon degradation, nitrogen input and retention, and secondary metabolism. Metabolomic profiling further identified cave-specific metabolite signatures, among which Biochanin A, 4-Hydroxybenzaldehyde, Vanillin, and Arachidonic acid were negatively correlated with Pd loads. Integrated pathway and network analyses showed that differential genes and metabolites jointly mapped to secondary metabolite biosynthesis, aminobenzoate degradation, and flavonoid degradation pathways, forming a microbe-metabolite-functional gene coupling network involving key taxa such as Rhodococcus, Pseudorhodoplanes, and Rhodoplanes. In vitro assays confirmed that 4-Hydroxybenzaldehyde, Coumarin, and Vanillin inhibited Pd growth. Structural equation modelling further indicated that environmental heterogeneity was associated with variation in Pd loads through microbial functional attributes and metabolite profiles. These findings suggest that naturally low-Pd cave soils are associated with coordinated environmental filtering, microbial functional specialization, and antifungal metabolite production, providing mechanistic insight into microbial and biochemical constraints on Pd persistence in cave reservoirs.

Animals

Congenital Laryngomalacia: Pathophysiology, Clinical Spectrum, and Holistic Management.

Congenital laryngomalacia is the most common cause of infant stridor and arises from interacting structural, neuromuscular, and inflammatory mechanisms that produce dynamic supraglottic collapse. Disease severity spans mild stridor to significant obstruction, aspiration, and failure to thrive, often influenced by comorbid medical conditions. Diagnosis relies on flexible laryngoscopy supported by instrumental swallowing studies and microdirect laryngoscopy and bronchoscopy when indicated. Most infants respond to conservative management, particularly targeted feeding modifications, while acid suppression offers benefit in selective cases. Supraglottoplasty provides effective, durable improvement for severe disease and significantly enhances infant outcomes and family quality of life.

Humans

Temporal shifts in gyrA mutation types and sublineage replacement in ST11 Salmonella enterica&#xa0;serovar Enteritidis over a decade (2014-2023): A genomic epidemiological study in Guangxi, China.

The overuse or abuse of antibiotics drives the global health threat of antimicrobial resistance. Although bans on certain veterinary antibiotics, such as colistin, have proven effective, the impact of fluoroquinolone stewardship on the evolution of the foodborne pathogen Salmonella enterica serovar Enteritidis (S. Enteritidis) remains unclear. Here, we conducted a decade-long (2014-2023) retrospective longitudinal genomic epidemiological analysis of 441&#xa0;ST11 S. Enteritidis isolates from Guangxi, China, alongside a global reference dataset of 4297 genomes. Our aim was to elucidate the effect of real-world antibiotic stewardship on the shift of gyrA point mutations and lineage distribution. Surveillance identified three global epidemic clade sublineages (GEC-L2, L3, L4), with the multidrug-resistant GEC-L4 (i.e., GC-c or MMC2), characterized by the gyrA mutation with amino acid substitution D87Y, being domestically dominant (70.07%, 309/441). Following China's 2016 ban on the veterinary use of critical fluoroquinolones, the proportion of the highly resistant GEC-L4 sublineage decreased continuously (from 86.84% in 2017 to 56.00% in 2023), while the less resistant GEC-L3 sublineage (i.e., GC-b or MMC1), mainly characterized by gyrA D87G, increased simultaneously (from 13.16% to 44.00%). This phenomenon might be attributed to the fact that the GEC-L4 sublineage exhibited a higher fitness cost compared with the GEC-L3 sublineage, as confirmed by the competition assay. A Random Forest Model validated that the gyrA mutation with amino acid substitution&#xa0;D87Y was the paramount feature for these sublineages' identification. In contrast, global data showed a continuous increase in gyrA mutations (from 8.63% in 2006 to 68.85% in 2024), primarily D87Y (from 1.44% to 31.15%) and D87N (from 4.32% to 22.95%), correlating with rising average fluoroquinolone consumption. This study provides direct genomic evidence that national-level antibiotic stewardship can drive the replacement of highly resistant sublineages with moderately resistant ones. These findings offer crucial scientific evidence for evaluating the impact of antibiotic management policies and inform strategies for the rational use of antimicrobials.

China

Selective monitoring of trace-level catechin and myricetin in herbal and aqueous matrices using magnetic MIP-DSPME: Optimization via design of experiments.

A novel dispersive solid-phase microextraction approach utilizing a magnetic molecularly imprinted polymer (MMIP) integrated with HPLC-UV detection was developed for the concurrent quantification of catechin and myricetin in herbal extracts and aqueous samples. The sorbent was engineered as a core-shell nanocomposite, consisting of a selective polymer layer deposited onto Fe3O4@SiO2-APTMS magnetic nanoparticles. Dual-template imprinting using catechin and myricetin generated complementary binding cavities within the polymer framework. Experimental variables influencing extraction were systematically screened and subsequently optimized. A Plackett-Burman design was first applied to identify the most influential factors, with pH and sorption time identified as the dominant variables. These parameters were subsequently fine-tuned using a central composite design, and the optimization process was completed in only 30 experimental runs. The sorption characteristics of the imprinted sorbent (MMIP) were compared with those of its non-imprinted counterpart (MNIP). The MMIP demonstrated markedly higher maximum binding capacities (Qmax), reaching 119.3&#xa0;mg&#xa0;g-1 for myricetin and 112.1&#xa0;mg&#xa0;g-1 for catechin, whereas the corresponding values for the MNIP were 32.55 and 32.08&#xa0;mg&#xa0;g-1, respectively. Moreover, the affinity constants (KL&#xa0;=&#xa0;0.760-0.950&#xa0;L&#xa0;mg-1) were approximately 2.3-fold higher for the MMIP, confirming its stronger and more selective interactions with the target analytes. The selectivity coefficients for the targeted flavonoids relative to structurally related compounds, including ferulic acid, p-coumaric acid, melatonin, and curcumin, exceeded 3.5 for the MMIP, whereas the corresponding values for the MNIP were close to 1.1, demonstrating the high molecular recognition capability of the imprinted sorbent. Method validation demonstrated limits of detection (LODs) of 0.33-0.59&#xa0;ng&#xa0;mL-1 and limits of quantification (LOQs) of 1.10-1.96&#xa0;ng&#xa0;mL-1, and excellent linearity over the concentration range of 5.0-5500&#xa0;ng&#xa0;mL-1 (R2&#xa0;>&#xa0;0.998). The method achieved recoveries of 93.96% to 105.69% with RSDs below 5.5%, while the preconcentration factors ranged from 209 to 229. Furthermore, the sorbent retained more than 95% of its extraction efficiency after four consecutive reuse cycles and more than 80% after six cycles, demonstrating excellent stability and reusability. The proposed method was successfully applied to the analysis of six medicinal plant extracts and water samples, showing negligible matrix interference and superior sensitivity, selectivity, and operational simplicity compared with conventional solid-phase extraction methods.

Flavonoids

Epithelial regeneration in the gastrointestinal tract.

The gastrointestinal tract possesses a remarkable regenerative capacity to maintain tissue homeostasis against various injuries. However, the intestine and stomach exhibit distinct regenerative strategies. In the intestine, damage to Lgr5-positive (Lgr5+) stem cells induces cellular plasticity and the emergence of transient Revival stem cells (RevSCs), a process critically dependent on YAP/TAZ signaling. Conversely, the stomach utilizes paligenosis, where quiescent p57-positive (p57+) mature chief cells act as reserve stem cells, dedifferentiating to restore damaged tissue. Although the cellular origins differ, both organs appear to share some common regenerative features, including transient activation of pro-proliferative programs such as YAP/TAZ signaling. In contrast, whether Retinoic Acid (RA) signaling also serves as a conserved mechanism for regenerative resolution in the stomach remains to be determined. In this review, we discuss the cellular and molecular mechanisms governing regeneration in these two organs. This comparative analysis provides a framework for future research.

Regeneration

Insights into the fate and dynamics of antibiotic resistance in multidrug-resistant Bacillus cereus during in vitro simulated gastrointestinal digestion.

Bacillus cereus, an important pathogen responsible for causing foodborne diseases worldwide, releases pore-forming enterotoxins, which target host epithelial cells, leading to osmotic lysis and ultimately manifesting as diarrheal syndrome. Moreover, some B. cereus strains carry antimicrobial resistance genes that confer multidrug resistance against a spectrum of antibiotics. Characterizing the survival traits of multidrug-resistant (MDR) B. cereus strains in the intestinal microenvironment is essential for developing targeted strategies to effectively manage diarrheal foodborne diseases caused by this pathogen. This study used whole-genome sequencing (WGS) to evaluate the pre- and post-digestion toxigenic potential, antimicrobial resistance profiles, and genetic diversity of MDR B. cereus strains isolated from food samples in Guangdong Province, China. The four B. cereus isolates investigated in this study exhibited a genetic diversity, as determined by multilocus sequence typing analysis of WGS data. All four isolates produced the diarrheal toxins Hbl, Nhe, and CytK to varying levels, indicative of their potential to cause outbreaks of foodborne diseases. Each of the four isolates exhibited resistance to more than three classes of antibiotics, fulfilling the criterion for multidrug resistance. At an initial concentration of 9 log colony-forming units (CFU)/mL, the intestinal concentration of these four isolates crossed the threshold required to induce widespread diarrhea in the general population. Under rice slurry protection, all tested isolates maintained intestinal concentration beyond the threshold when the initial concentration was increased to &#x2265;8 log CFU/mL. Moreover, the upregulations of genes associated with acid tolerance, bile tolerance and stress response were observed in the surviving MDR B. cereus isolates. Digestion markedly altered the antibiotic resistance profiles of the MDR B. cereus isolates. In the absence of a food matrix, the MDR isolates lost their resistance to imipenem, meropenem, amoxicillin-clavulanic acid, and trimethoprim-sulfamethoxazole post-digestion and was influenced by the initial concentration of the strains. In the presence of food matrix rice slurry, the effects of digestion on the antibiotic resistance of MDR B. cereus isolates can be mitigated, enabling them to maintain their antibiotic resistance to the greatest extent. Most remarkably, after digestion, the isolates Bce055 and Bce166 exhibited newly emergent resistance to cefotetan and trimethoprim-sulfamethoxazole, respectively. Our findings clarify the fate of MDR B. cereus isolates in the gastrointestinal tract and inform the development of prevention and control strategies for foodborne diseases caused by this pathogen.

Drug Resistance, Multiple, Bacterial

First Report of Fibromyxoma in a Greater Amberjack (Seriola dumerili) From Aquarium of Genoa.

In teleosts, mesenchymal tumours like fibromas are frequently observed, whereas their malignant counterparts, fibrosarcomas, occur only sporadically. In our study, an adult female greater amberjack (Seriola dumerili) reared at the Aquarium of Genoa developed a slow-growing mass protruding from the ventral right side of the head. The tissue was firm and white greyish with localized cranial haemorrhaging on the external surface. Cut-section examination showed a homogeneous, dry, whitish and richly vascularized tissue layout. Tissue samples from the mass were stained with Masson's Trichrome, Alcian Blue-PAS (pH&#x2009;2.5), and Toluidine blue for differential diagnosis. Microscopically, it was characterized by alternating collagenous spindle-cell septa and hypocellular metachromatic myxoid areas positive for acidic mucopolysaccharides and glycosaminoglycans. The absence of cellular atypia, mitotic activity and necrosis confirms the diagnosis of fibromyxoma. Documenting rare tumours in aquarium fish expands comparative pathology literature and highlights public aquaria as valuable research platforms for long-term health monitoring under controlled husbandry conditions.

fibromyxoma

Comprehensive study on pesticide residues and mycotoxins in freeze-dried strawberries and raspberries.

Freeze-dried fruit has gained popularity because it preserves the flavour and nutritional value of fresh fruit while providing extended shelf life. Despite this, there are concerns regarding its chemical safety. This study evaluated 58 freeze-dried fruit products from the Czech retail market, focusing on potential contamination. Pesticide residues and mycotoxins were determined using LC-MS/MS and GC-MS/MS. Overall, 111 pesticide residues (or their metabolites) and 3 mycotoxins were quantified. After applying processing factors, 12 pesticide residues exceeded EU maximum residue limits. Prohibited substances, including carbofuran, omethoate, and haloxyfop, were detected. Tenuazonic acid was found in 71% of samples, while alternariol and tentoxin were detected less frequently. More than half (54%) of strawberry samples contained 10 or more pesticide residues, indicating potential cumulative exposure concerns, particularly for children with lower body weight. These findings highlight the need for continued monitoring of freeze-dried fruits and further assessment of dietary exposure.

Pesticide Residues

Integrated metabolomic, transcriptomic, and proteomic analyses reveal changes in the non-volatile metabolite profile of LED light-withered oolong tea.

LED light withering is a crucial method for overcoming weather limitations and enhancing the quality of oolong tea. To elucidate the underlying molecular mechanisms, this study simulated solar spectra using multiwavelength LED light and compared the resulting metabolic, transcriptomic, and proteomic profiles during the enzymatic-catalysis process (ECP) in oolong tea processing. Results indicated that LED light withering altered gene expression and protein regulation of secondary metabolism, particularly in the flavonoid biosynthesis pathway. These shifts encompassed key quality-related compounds, including flavonoids (quercetin-3-O-rhamnoside, dihydroquercetin), amino acids (L-asparagine, L-histidine), guanosine 5'-monophosphate (GMP), and carbohydrates. Furthermore, LED light withering accelerated tea leaf water loss, influenced gene expression involved in photosynthetic cellular components (chloroplasts, thylakoids), increased ascorbate peroxidase regulation under stress, and subsequently modulated energy metabolism and signal transduction in tea leaves. This study offers molecular theoretical framework for the controlled light-withering of oolong tea under bad weather and the associated improvements in its quality.

Camellia sinensis