Search Results (77)

Radium and barium are hazardous contaminants that frequently occur in wastewater, posing significant risks to human health and the environment. This study provides a comparative evaluation of five synthetic zeolites—3A, 4A, 5A, 13X (commercial), and NaP1 (synthesized from fly ash)—representing three distinct framework types (LTA, FAU, and GIS) for the removal of radium from real saline mine water (Upper Silesia Coal Basin, Poland) and barium from synthetic water. The zeolites were characterized by XRD, SEM-EDS, and N₂ adsorption, and tested in both granular and fine-powder forms using sequential batch adsorption experiments. For radium removal from mine water, zeolite NaP1 demonstrated superior performance, maintaining low ²²⁶Ra effluent activity (<1 Bq/L), even after treating ~50 L of water. Zeolites 3A, 4A, 5A, and 13X exhibited significantly lower performance than NaP1, showing poor selectivity for radium. In the barium batch tests, all tested zeolites achieved removal efficiencies exceeding 95% at low initial concentrations (100 mg/L). At higher concentrations (2000 mg/L), zeolites 3A, 4A, and 13X exhibited the highest adsorption capacities, with zeolite 4A achieving the maximum value of approximately 239.9 mg/g. The experiments demonstrated that idealized laboratory conditions can substantially overestimate sorbent performance relative to real water systems. Full article

Cadmium (Cd), a highly mobile and phytotoxic heavy metal, threatens plant growth and food safety and has increased interest in woody plant-based phytoremediation. However, the genome-wide characteristics of the NAC transcription factor family and its role in Cd tolerance remain largely unknown in pomegranate (Punica granatum L.), a stress-tolerant woody plant. In this study, 121 PgNAC genes were identified from the chromosome-level genome of the pomegranate cultivar ‘Tunisia’. Phylogenetic analysis classified these genes into two major groups and 16 subgroups. PgNAC genes were unevenly distributed across the eight chromosomes and showed evident clustered distribution patterns. Synteny and Ka/Ks analyses further revealed that segmental and tandem duplication jointly shaped the expansion of the PgNAC family, while the duplicated pairs have largely evolved under strong purifying selection. Conserved motif and gene structure analyses showed that PgNAC proteins possessed a highly conserved N-terminal NAM domain, whereas their C-terminal regions were relatively divergent. Promoter analysis further identified abundant hormone- and stress-responsive cis-elements, suggesting diverse regulatory roles of the PgNAC family. Transcriptome profiling identified PgNAC87, a member of the NAP subfamily, as a Cd-responsive candidate gene that was consistently upregulated in both roots and leaves under Cd stress. Heterologous overexpression of PgNAC87 in tobacco significantly enhanced Cd tolerance, as reflected by alleviated growth inhibition, increased antioxidant enzyme activities and osmotic adjustment substances, and reduced oxidative damage. Collectively, our results clarify the evolutionary features of the PgNAC family and its involvement in Cd-induced transcriptional regulation, while highlighting PgNAC87 as a potential genetic target for enhancing Cd tolerance in pomegranate and related woody species. Full article

Although numerous studies have focused on the potential application of heterotrophic nitrification–aerobic denitrification (HNAD) bacteria in wastewater treatment, research exploring their potential in aquaculture biofloc systems remains limited. In this study, a promising HNAD strain, identified as Stutzerimonas stutzeri MJ20, was isolated from mature biofloc. This strain efficiently utilized low-cost carbon sources (e.g., glucose) and small-molecule carbon sources (e.g., sodium acetate and sodium succinate). Under conditions with glucose as the carbon source, a carbon-to-nitrogen (C/N) ratio of 15, pH 6–9, temperature 25–35 °C, salinity 0–35‰, and shaker speed of 0–150 rpm, it achieved removal rates of 95–100% for NH₄⁺-N, NO₂⁻-N, and NO₃⁻-N at initial concentrations of 100 mg/L each. Even at higher concentrations (up to 200 mg/L NH₄⁺-N and 500 mg/L for both NO₂⁻-N and NO₃⁻-N), removal rates exceeded 99%. Under mixed nitrogen sources, strain MJ20 demonstrated efficient nitrogen removal, preferentially utilizing NH₄⁺-N, with only minimal and transient accumulation of nitrite and nitrate. Genomic analysis revealed that MJ20 carries key denitrification genes, including napA, nirS, norB and nosZ, and possesses complete pathways for nitrate reduction to nitrogen gas and ammonia assimilation, although typical autotrophic nitrification genes were not detected. Combined genomic data and autotrophic culture experiments indicated that, in addition to utilizing various organic carbon sources, the strain also exhibited certain autotrophic growth capabilities. Furthermore, MJ20 showed strong flocculation ability (flocculation rate > 96% within 16 h), sensitivity to multiple common antibiotics, and no toxicity to zebrafish, demonstrating favorable biosafety. In simulated seawater aquaculture wastewater with a C/N ratio of 5, it achieved a total nitrogen removal rate exceeding 94% within 72 h. These results indicate that strain MJ20 possesses comprehensive advantages, including efficient nitrogen removal, broad carbon source adaptability, strong environmental resilience, minimal accumulation of intermediate nitrogen products, excellent flocculation ability, and high biosafety. These traits highlight its potential for application in biofloc systems and in treating aquaculture tail water with a low C/N ratio. This study provides theoretical insights and practical guidance for screening HNAD bacteria suitable for biofloc systems. Full article

Root-zone nitrogen fertilization (RZF) can increase crop N uptake and yield, yet the underlying rhizosphere N-cycling functional mechanisms remain insufficiently resolved. In a field experiment with winter oilseed rape (Brassica napus L.), RZF was compared with conventional fertilization (CF) under the same N input rates, alongside a zero-N control (N0). Compared with CF, RZF significantly increased seed yield (by 0.44 t ha⁻¹) and aboveground N uptake (by 20.45 kg ha⁻¹), while simultaneously enriching rhizosphere mineral N pools (NH₄⁺–N and NO₃⁻–N by 54.50% and 56.02%, respectively). Shotgun metagenomics revealed that RZF reprogrammed rhizosphere N-cycling functional potential, characterized by enhanced nitrogen fixation, reduced nitrification and denitrification, and a tendency toward increased assimilatory nitrate reduction. These module-level shifts were supported by concordant changes in key functional genes, indicating greater genetic potential for N retention and assimilation (nifD, glnA, gltB, nasA, napB, nrfA) and reduced potential for nitrification- and denitrification-driven N losses (amoB/C, narI, nirK, norB). Taxonomic composition analysis showed enrichment of Bradyrhizobium and suppression of key nitrifier taxa (Nitrosospira and a Nitrososphaeraceae-affiliated taxon) under RZF. Rhizosphere pH exhibited the strongest Mantel correlation with multiple N-cycling modules, and rhizosphere available N (AN; sum of NH₄⁺–N and NO₃⁻–N) was positively associated with plant N traits and yield. Structural equation modeling supported a pathway in which a functional balance index (retention/assimilation vs. loss/oxidation) increased AN (0.22), and AN strongly promoted yield (0.90). Collectively, these results elucidate a rhizosphere-centered mechanism whereby localized N placement strengthens soil–plant N coupling and enhances crop productivity through reprogramming microbial N-cycling functional potentials, positioning rhizosphere N processes as a key mechanistic bridge for microbiome-informed optimization of root-zone fertilization. Full article

Carnation (Dianthus caryophyllus L.) is a globally important cut flower, and its postharvest longevity is a key determinant of commercial value. Flower senescence in carnation is a genetically programmed yet environmentally modulated process involving coordinated physiological, biochemical, hormonal, and molecular changes. This review synthesizes recent advances in the regulation of carnation petal senescence, with a particular focus on ethylene (ETH)-dependent signaling, hormonal crosstalk, metabolic regulation, and emerging molecular control layers. ETH acts as the central regulator of senescence, interacting with abscisic acid, cytokinins, gibberellins, and auxins to control the timing and progression of petal aging. Recent studies have identified key regulatory genes, including DcACS1, DcACO1, DcEIL3-1, DcWRKY75, DcNAP1/2, DcATX1, and m⁶A methylation-related factors, revealing multilayered control of senescence progression. Emerging evidence further demonstrates that RNA m⁶A modification links ETH signaling with antioxidant capacity and metabolic homeostasis. We propose an integrated regulatory network model that connects hormonal crosstalk, environmental cues, transcriptional control, and post-transcriptional regulation. This updated framework provides mechanistic insights into developing targeted postharvest treatments and breeding strategies to extend vase life of cut carnation flowers. Full article

Leishmania infantum is the etiological agent of visceral leishmaniasis (VL) and is linked to cases of cutaneous leishmaniasis in dogs. Dogs often develop severe systemic disease and serve as the primary reservoir of L. infantum. Although several vaccine candidates are under development, no vaccine for visceral leishmaniasis has been approved for human use to date. Chemotherapeutic treatment is hampered by toxicity, cost, and the emergence of parasite-resistant strains. Immunotherapy, combining chemotherapy with modulation of Th1 responses, is a promising therapeutic approach. Helicobacter pylori neutrophil-activating protein (HP-NAP), an immunomodulatory protein from Helicobacter pylori, is known to promote Th1 immune responses. A Th1 response activates macrophage promoting parasite killing, while a Th2 response favors disease progression. Macrophages are central for infection, either eliminating parasites (Th1 response) or supporting their persistence (Th2 response). IL-12 is a crucial cytokine in driving Th1 immunity and counteracting Th2 responses. We therefore investigated the role of HP-NAP in an in vitro model of L. infantum macrophage infection. Canine monocyte-derived macrophages from seven dogs were incubated with L. infantum promastigotes. More than 85% of macrophages from all donors were infected, with approximately seven amastigotes per cell. HP-NAP treatment significantly reduced all infection parameters and induced IL-12 production. Collectively, these findings suggest that HP-NAP may represent a promising candidate for adjuvant immunotherapies and vaccine development against L. infantum. Full article

Rapeseed (Brassica napus L.) is a major oilseed crop worldwide, particularly valued for its high yield potential, favorable fatty acid composition, and its bioactive compounds that improve nutritional and industrial quality. However, its productivity and oil quality are increasingly compromised by climate change-induced water scarcity, particularly in semi-arid Mediterranean regions. In this study, the performance of 17 genotypes was evaluated under well-watered (irrigated) and rainfed (stressful) conditions across two contrasting locations, Douyet Experimental Station (DYT) and Ecole Nationale d’Agriculture de Meknès (ENAM), during the 2023/2024 growing season. The assessment concerned seed yield, oil traits, and nutraceutical quality. The results obtained show that drought stress significantly reduced seed yield by about 26% (from 2.29 to 1.69 t ha⁻¹) and decreased oil content by about 8.3% (from 41.1% to 37.7%). The highest reductions were observed for sensitive genotypes, particularly ‘IND23’, ‘IND82’, and ‘H2M-5’, while ‘Moufida’, ‘Nap9’, and ‘TP2’ maintained seed and oil yield above the overall average across both water regimes. Drought also impacted the accumulation of secondary metabolites, with mean total phenolic content increasing from 5.41 to 9.98 mg GAE g⁻¹ (+84.5%) and total flavonoid content rising from 25.25 to 34.93 mg QE g⁻¹ (+38.3%) under rainfed conditions, accompanied by marked increases in antioxidant activity (DPPH, ABTS), particularly for ‘Moufida’, ‘Nap9’, ‘TP2’, and ‘Marina’. Oil quality indices remained within Codex Alimentarius standards, with a slight increase in acidity values accompanied by a decrease in peroxide values, thus suggesting improved oxidative stability. Principal component analysis grouped genotypes into distinct clusters, with an elite group (‘Moufida’, ‘Nap9’, and ‘TP2’) characterized by yield stability, accumulation of phenolics, and high antioxidant activity, thus confirming their strong adaptation to the dry conditions of the Mediterranean region. These drought-tolerant lines, with high agronomic performance combined with good nutritional quality, can be recommended as valuable cultivars for sustainable and high-quality rapeseed production in dry Mediterranean regions. Full article

Eutrophication threatens vulnerable plateau lakes, yet the gene-level microbial processes behind spatial heterogeneity of sediment carbon (C), nitrogen (N), phosphorus (P) and sulfur (S) cycling and their environmental driver remain unclear. This study first applies the high-throughput Quantitative Microbial Ecology Chip (QMEC) to quantify 71 functional genes involved in geochemical cycling in sediment of a large Chinese plateau lake, Erhai, aiming to elucidate how environmental factors shape the spatial distribution and coupling patterns of these genes. The results revealed that total functional gene abundance exhibited a pronounced south-to-north decline, with key genes (rbcL, mct, nirS, nosZ, phoD, pqqC and yedZ) being significantly higher in the southern sector (p < 0.05). Lignocellulose-degrading genes (abfA, xylA and mnp) exceeded 10⁶ copies g⁻¹ and were significantly enriched in the south, indicating faster organic-matter turnover. Denitrification dominated the nitrogen cycle, with nirS-type denitrifiers being overwhelmingly prevalent; genes associated with nitrate reduction (napA, narG) were also significantly more abundant in the south. Sediment total phosphorus (TP) was significantly correlated with genes involved in carbon fixation, methane production, nitrogen fixation and sulfur metabolism (Mantel test, p < 0.05), suggesting that TP is a key driver of microbial nutrient cycling in Erhai sediment. Furthermore, co-abundance of these functional genes was observed across all sites (Spearman correlation, p < 0.05), which in turn implies potential coupling of the major elemental cycles. Accordingly, the differentiation of the carbon, nitrogen, phosphorus and sulfur cycling genes and metabolic potential in the different sectors reveals heterogeneous microbial regulation of Erhai’s endogenous nutrient cycling. It highlights precision and differentiated management as a key for large lake restoration. Full article

Kaolin from the Donigazza deposit (NW Sardinia, Italy) was used to investigate the mechanisms of zeolite crystallization under alkaline hydrothermal conditions. The starting material, composed mainly of kaolinite and opal-CT with minor quartz and low iron content, was reacted with NaOH solutions (1–5 mol L⁻¹) at 100 °C for 12–168 h. XRD analyses revealed the formation of zeolitic and related phases, including NaP1, NaP2, analcime, sodalite, and cancrinite, with zeolite contents reaching up to 100%. The extent of kaolinite dissolution varied with both NaOH concentration and reaction time, with complete transformation occurring at ≥3 mol L⁻¹ and ≥48 h. SEM imaging showed idiomorphic crystals (100 nm–10 μm) and globular nanoparticles (<50 nm), likely Na-Al-Si gels. Phase distribution reflected evolving solution chemistry, particularly changes in the Si/Al ratio due to differential dissolution of opal-CT and kaolinite. Crystallization proceeded via both classical (monomer addition) and non-classical (particle attachment) pathways, influenced by supersaturation, gel composition, and reaction kinetics. The transition from NaP1 to NaP2, and the development of metastable phases, indicate kinetic control consistent with Ostwald’s step rule. These results provide insights into the complex dynamics of zeolite formation from natural aluminosilicate precursors in alkaline environments. Full article

Municipal solid waste incineration (MSWI) fly ash, classified as hazardous waste (HW18) due to the presence of heavy metals and dioxins, necessitates both harmless treatment and resource utilization. In this study, a Na-P1 zeolite adsorbent was synthesised from MSW incineration fly ash using its intrinsic Si and Al sources, supplemented by silica sol and sodium aluminate solution. The synthesised zeolite was employed for the adsorption removal of tetracycline hydrochloride (TCH) from wastewater. Under the optimised conditions (initial TCH concentration of 10 mg·L⁻¹, adsorbent dosage of 0.4 g·L⁻¹, pH 5.0, temperature 45 °C, and contact time 60 min), a maximum adsorption capacity of 14.8 mg·g⁻¹ and a removal efficiency of 59.1% were achieved. Kinetic analysis revealed that the adsorption process followed the pseudo-first-order model (R² = 0.975). The Langmuir isotherm provided a better fit than the Freundlich model (R² = 0.988), indicating monolayer adsorption on homogeneous sites. Thermodynamic parameters (ΔG < 0, ΔH > 0) confirmed that the adsorption was spontaneous and endothermic, with higher temperatures favoring enhanced TCH adsorption. This work demonstrates the feasibility of converting hazardous MSW incineration fly ash into a value-added Na-P1 zeolite adsorbent with excellent performance for antibiotic wastewater treatment, thereby offering a sustainable strategy for fly ash resource recovery and environmental remediation. Full article

Polycyclic aromatic hydrocarbons (PAHs) are persistent organic pollutants with significant ecological and public health implications, particularly in urban wetlands exposed to chronic anthropogenic stress. This study evaluates the occurrence, spatial distribution, seasonal variability, and ecological risk of three low molecular weight PAHs—naphthalene (NAP), phenanthrene (PHEN), and anthracene (ANT)—in surface waters of Caño La Malaria, the main freshwater source of Cucharillas Marsh, Puerto Rico’s largest urban wetland. Surface water samples were collected at four locations during both wet- and dry-season campaigns. Samples were extracted and quantified by GC-MS. NAP was the dominant compound, Σ3PAHs concentrations ranging from 7.4 to 2198.8 ng/L, with higher wet-season levels (mean = 745.79 ng/L) than dry-season levels (mean = 186.71 ng/L); most wet-season samples fell within the mild-to-moderate contamination category. Compositional shifts indicated increased levels of PHEN and ANT during the wet season. No significant spatial differences were found (p = 0.753), and high correlations between sites (r = 0.96) suggest uniform input sources. Diagnostic ratios, inter-species correlations, and principal component analysis (PCA) consistently indicated a predominant pyrogenic origin, with robust PHEN–ANT correlation (r = 0.824) confirming shared combustion-related sources. PCA revealed a clear separation between dry- and wet-season samples, with the latter showing greater variability and stronger associations with NAP and ANT. Ecological risk assessment using hazard quotients (HQ_water) indicated negligible acute toxicity risk across all sites and seasons (<0.01); the highest HQ_water (0.0095), observed upstream during the wet season, remained within this range. However, benchmark exceedances by PHEN and ANT suggest potential chronic risks not captured by the acute ERA framework. These findings support integrated watershed management practices to mitigate PAH pollution and strengthen long-term ecological health in tropical urban wetlands. Full article

Electroacupuncture (EA) has shown analgesic potential for neuropathic pain, yet its underlying molecular mechanisms remain incompletely understood. This study aimed to investigate whether EA relieves neuropathic pain by modulating CCL2/CCR2 signaling and microglial activation in the spinal cord. Neuropathic pain was induced in rats by L5 spinal nerve ligation. EA was administered at acupoints ST36 and GB34 (1 mA, 2 Hz, 30 min) daily from postoperative days 3 to 7. Rats were assigned to anesthetized control (ANE), non-acupoint stimulation (NAP), and acupoint stimulation (ACU) groups. Pain behavior was evaluated using paw withdrawal threshold and latency. Western blot and immunofluorescence were used to assess CCL2, CCR2, Iba1, IL-1β, and TNF-α expression in the L4–L6 spinal cord. EA significantly attenuated mechanical allodynia and thermal hyperalgesia in the ACU group, accompanied by reductions in CCL2, CCR2, microglial marker Iba1, and pro-inflammatory cytokines. Most importantly, intrathecal administration of recombinant CCL2 completely abolished EA’s analgesic effects, establishing the causal necessity of CCL2/CCR2 signaling in EA-mediated analgesia. These findings suggest that EA exerts its analgesic effects through downregulation of the CCL2/CCR2 pathway and inhibition of microglial activation. The reversal of EA’s effects by exogenous CCL2 supports the critical role of spinal chemokine signaling in EA-mediated analgesia. Full article

The anaerobic ammonium oxidation (anammox) process offers potential for saline wastewater treatment but is hindered by salt inhibition. This study investigates the salt tolerance mechanisms of granular (R1), biofilm-carrier (R2), and floccular (R3) sludge in up-flow anaerobic sludge blanket (UASB) reactors under 0–20 g/L NaCl. Granular sludge outperformed other biomass types, maintaining >90% ammonia nitrogen (${\mathrm{NH}}_4^{+}$-N) removal at 20 g/L NaCl due to structural stability and extracellular polymeric substances (EPS) adaptation (shift from hydrophobic proteins to polysaccharides). Microbial analysis revealed a transition from Planctomycetes/Proteobacteria to salt-tolerant Pseudomonadota, with Candidatus_Kuenenia replacing Candidatus_Brocadia as the dominant anaerobic ammonium oxidation bacteria (AnAOB) (reaching 14.5% abundance in R1). Genetic profiling demonstrated coordinated nitrogen metabolism: Hzs/Hdh inhibition (>85%) and NirBD/NrfAH activation (0.23%) elevated ${\mathrm{NH}}_4^{+}$-N, while NarGIV/NapA decline (1.10%→0.58%) increased nitrate nitrogen (${\mathrm{NO}}_3^{-}$-N). NxrB/NirSK maintained low nitrite nitrogen (${\mathrm{NO}}_2^{-}$-N), and GltBD upregulation (0.43%) enhanced osmoregulation. These findings underscore the superior resilience of granular sludge under high salinity, linked to microbial community shifts and metabolic adaptations. This study provides critical insights for optimizing anammox processes in saline environments, emphasizing the importance of biomass morphology and microbial ecology in mitigating salt inhibition. Full article

A 56-day trial was conducted to assess the effects of rice straw (RS) and bamboo flour (BF) on growth performance, water quality, gill histology, and the bacterial community of water and the intestine of mandarin fish (Siniperca chuatsi) in biofloc technology systems. The results showed that mandarin fish in the RS and BF groups had comparable survival rates of 100.00 ± 0.00 and 93.33 ± 3.85%; feed conversion ratios of 1.13 ± 0.02 and 1.40 ± 0.15; and weight gain rates of 112.21 ± 1.56 and 100.92 ± 6.45%, respectively. From days 11 to 56 of the farming period, the BF group was more effective than the RS group in removing total ammonia nitrogen (TAN) and NO₂⁻-N, maintaining TAN levels below 0.24 ± 0.05 mg/L. During the early stage of the experiment, the TAN level in the RS group was higher; however, with the supplementation of a carbon source, it gradually decreased and eventually stabilized at 0.13 ± 0.03 mg/L later in the farming period. The secondary gill lamella in the RS group was curved and showed hyperplasia, and the basal gill lamellae showed an increase in the volume of interlamellar cell mass in the BF group. Genes related to denitrification (narG, napA, nirS, nirK, and nosZ) and anammox showed higher expression levels in the BF group than in the RS group, although the differences were not statistically significant (p > 0.05). The results of 16S rRNA sequencing research showed that both treatment groups’ intestinal and water bacterial communities had comparable levels of richness and diversity. Pseudomonas mosselii was the dominant bacterial species in the water. In the BF group, the dominant intestinal species were Bacillus halodurans and Caldalkalibacillus thermarum, while in the RS group, the dominant species was Plesiomonas shigelloides. In conclusion, rice straw and bamboo flour are applicable in BFT systems for mandarin fish culture, with good growth performance and water quality. The BF group showed higher nitrogen removal efficiency and denitrification gene expression than the RS group. Full article

Antimicrobial susceptibility testing (AST) is not routinely performed for C. difficile infection (CDI); however, reports of antimicrobial resistance to various antibiotics have increased. This study aimed to assess the rate of antimicrobial resistance to four antimicrobials (vancomycin, metronidazole, tigecycline, and ciprofloxacin) to assess risk factors for antimicrobial resistance and evaluate MIC variation in patients with recurrence. Data from consecutive patients with CDI admitted to our institution between 1 January 2022 and 30 April 2023 were collected. We performed AST with gradient diffusion and NAAT to evaluate the presumptive presence of R027/NAP1 and toxin production genes. Antimicrobial susceptibility testing was performed on 108 available isolates. We did not find any resistance to vancomycin (median MIC 0.5 μg/mL), metronidazole (median MIC 1 μg/mL), and tigecycline (median MIC 0.016 μg/mL), while resistance to ciprofloxacin was detected in all the samples. Among the recurrent isolates, 37.5% displayed a 2-fold MIC increase for vancomycin, 75% for metronidazole, and 37.5% for tigecycline. After stratifying clinical outcomes according to vancomycin MIC, patients with higher MIC experienced increased 28-day mortality (p value 0.009). Our results were concordant with European surveillance data. MIC increase in all tested antibiotics in patients with CDI warrants further research since decreased susceptibility has been associated with clinical failure. Full article