Search Results (1,551)

To clarify how nitrogen (N) and water regulate the microbe mediated carbon (C) cycle in farmland, a 3-year experiment was conducted in a wheat–maize rotation at Jiaozhou Station, North China. Twelve treatments combined four drip irrigation regimes (T1: no irrigation; T2: 40 mm irrigation at flowering; T3: 40 mm irrigation at the grain filling stage; T4: both, 40 mm each) and three N levels (N0: 0 kgN·hm⁻²; N1: 92 kgN·hm⁻²; N2: 184 kgN·hm⁻²). In this study, we measured wheat yield and biomass, soil organic carbon and nitrogen content, soil respiration, soil microbial community, and C-metabolic genes. The results showed that wheat yield increased with N, peaking at 8949.81 kg·hm⁻² in the N2T3 treatment, while irrigation had no significant independent effect on yield but interacted with nitrogen fertilization: under identical nitrogen levels (N1, N2), yields in the T1 and T2 treatments were significantly lower than those in the T3/T4 treatments. The soil organic carbon content in N2 was significantly higher; the soil C/N ratio was highest in N2, and T3 resulted in a significantly higher C/N ratio than T1 under the same N level; total soil respiration in N0 was significant lower, and T4 had higher respiration than T2 under the same N level. N addition increased Actinobacteriota, Chloroflexi, Thaumarchaeota, and Ascomycota, while decreaing Proteobacteria and Acidobacteriota. No reduction in fungal phylum was observed with nitrogen addition. N application significantly upregulated key enzymes in the pentose phosphate pathway (e.g., transketolase K00615, transaldolase K00616), while irrigation increased phosphoserine aminotransferase (K00831) abundance and decreased methylmalonyl-CoA mutase (K01848) abundance. N2T3 maintains high SOC content while achieving maximum yield, promoting soil fertility retention. Compared to T4, N2T3 also enhances water use efficiency. The N2T3 treatment (high N and grain filling stage irrigation) achieved the optimal balance between high wheat yield and SOC sequestration. Full article

This study optimized γ-aminobutyric acid (GABA) formation in Vietnamese fermented pork (nem chua) using a central composite design to tune salt, sugar, and monosodium glutamate (MSG) under co-inoculation with Lactiplantibacillus plantarum CP1.2 and Pediococcus acidilactici CP1.4. Fermentations proceeded at room temperature; pH, titratable acidity, GABA (colorimetry), formal nitrogen, ammoniacal nitrogen (indophenol blue), and microbial counts were measured, with a packaging comparison between polypropylene (PP) and polyethylene (PE). Response surface analysis (R² = 0.8897) predicted an optimum at 2.0% salt, ~15.9–16.0% sugar, and ~2.9–3.0% MSG, yielding 7.44 mg/g GABA. Validation at these conditions achieved higher GABA (8.32 ± 0.24 mg/g), with pH near 4.70 and lactic acid ~18.5 g/kg. Across seven storage days, GABA peaked at day 1 (8.72–8.84 mg/g) and declined to 4.74–5.07 mg/g (day 7) as acidity increased. PE tended to preserve GABA better and reduced aerobic counts relative to PP, whereas PP limited ammoniacal nitrogen later in storage; lactic acid bacteria remained abundant (≥9.4 log CFU/g). Sensory attributes (color, aroma, taste, firmness) decreased over time but were higher in PE. The results show that balanced seasoning ratios, starter cultures, and packaging can maximize GABA enrichment while maintaining safety and quality in nem chua, providing a practical basis for scale-up of GABA-enhanced fermented meat products and tailoring shelf-life with packaging. Full article

This study investigated the effects of varying proline supplementation doses in weaned foals. Twenty-eight weaned foals (approximately 5 months of age; body weight: 54.45 ± 11.33 kg; with an equal number of males and females) were randomly assigned to one of four groups—a control group, a low-dose group (20 mg/kg·d), a medium-dose group (40 mg/kg·d), and a high-dose group (60 mg/kg·d)— receiving continuous supplementation for 60 days. Blood samples were collected periodically for the analysis of hormones, antioxidants, immune parameters, and plasma amino acids. Concurrently, fecal 16S rRNA sequencing was performed to assess the microbial community composition. We observed a significant time-dependent interaction between medium-to-high proline supplementation and time. Proline supplementation resulted in dose-dependent increases in foal body weight (p = 0.002), hormone levels (p < 7.49 × 10⁻⁶), antioxidant capacity (p < 1.56 × 10⁻³), immune function (p < 0.005), and key blood biochemical parameters (p < 0.019). Concurrently, supplementation with medium and high doses of proline significantly reduced the plasma concentrations of amino acids such as proline and arginine (p < 0.05). The medium dose achieved the optimal balance between promoting growth and maintaining high nitrogen utilization efficiency. At the microbial level, medium-dose proline significantly enhanced fecal microbial diversity, particularly enriching characteristic taxa like g_Christensenellaceae_R-7_group. Furthermore, functional inference from PICRUSt2 revealed that medium-dose proline supplementation was associated with a higher microbial potential for amino acid degradation and metabolism, in line with the decreasing plasma concentrations of the corresponding amino acids. This research enhances our understanding of the “host–microbiota interaction” mechanism in weaned foals and provides important theoretical support for mitigating weaning stress and optimizing nutritional strategies. Full article

Within the LIFE PREPAIR project, the BAT-Tool Plus (released in February 2022) was developed to estimate ammonia (NH₃) and greenhouse gas emissions from intensive livestock farming in the Po-basin, a hotspot for agricultural air pollution. The tool applies a nitrogen mass balance approach, considering housing, storage, treatment, and land application phases, integrating EU Best Available Techniques (BAT) standards. The BAT-Tool includes high-resolution and tailored methodologies, allowing single farms and regional-scale simulations. In this study, the BAT-Tool was applied to the Po-basin using 2023 data from the National Livestock Database and regional statistics on manure management. The results show that around one-third of nitrogen excreted by livestock is lost as NH₃, confirming livestock as the dominant source of emissions compared to fertilizers. In this paper, ammonia emissions and nitrogen load to fields were estimated, analyzing potential reductions achievable with wider adoption of BAT. The BAT-Tool provides standardized, transparent estimates, supporting regulatory compliance, emission inventories, and policy planning. Its scalability from farms to district scale makes it a reference model for improving nitrogen management and reducing PM_2.5 precursors in northern Italy and potentially across the EU. Full article

Nowadays, waste that can be used for environmental purposes, such as WBA (woody biomass ash), is particularly important. The presented research assessed the effect of soil application of WBA in conjunction with PFM (post-fermentation mass) on the stabilization of soil properties. WBA was applied in three increasing doses (0.5, 1.0, and 1.5 HAC). PFM was applied as follows: ULF (unseparated liquid fraction), SSF (separated solid fraction), and SLF (separated liquid fraction). PFM doses were balanced with the amount of nitrogen introduced into the soil. The study was based on a pot experiment with maize. The applied doses of WBA had a highly significant and positive effect on the stabilization of basic soil properties. After WBA application, hydrolytic acidity decreased (by 30%), soil pH increased (by 1.83 units), total base cation increased (by 66%), available potassium (by 119%), phosphorus (by 44%), and magnesium content (by 38%) as well as electrolytic conductivity increased (by 11%). Furthermore, an increase in soil carbon content and an improvement in the carbon-to-nitrogen ratio were noted. These observed results were further enhanced by the simultaneous application of WBA and the used PFM fractions, of which the liquid fractions (ULF and SLF) had the strongest effect. Full article

Phosphate tailings (PTs) are typical industrial byproducts that can rapidly neutralize soil acidity. However, their acid-neutralizing efficacy, long-term application optimization mechanisms, and high-yield regulation pathways for crops remain unclear. This study conducted a corn-potato crop rotation field trial on acidic soils, investigating the effect of different PT application rates (T: CK, 0 t·ha⁻¹; PTs-1, 6 t·ha⁻¹; PTs-2, 9 t·ha⁻¹; PTs-3, 15 t·ha⁻¹) in a multiple cropping system (C: late autumn potatoes (LAP)-early spring potatoes (ESP)-summer maize (SM)). The results showed that two consecutive applications of 9 t·ha⁻¹ of PTs produced optimal results, increasing the LAP yield by 12.82% and the soil quality by 76.51%, while improving the ESP soil quality by 46.21%. The higher yield was mainly attributed to a significant increase in the soil pH (0.72–1.58 units) and enhanced chemical and biological properties (higher exchangeable calcium (ExCa), exchangeable magnesium (ExMg), the total exchangeable salt base ion (TEB), and catalase (CAT) and urease (UE) content and lower soil exchangeable acidity (EA), exchangeable hydrogen ion (ExH), and exchangeable aluminum (ExAl) levels). Notably, a synchronized increase in the total phosphorus (TP) and total potassium (TK) during LAP cultivation, combined with simultaneous growth of TP, available nitrogen (AN), and available phosphorus (AP) during ESP cultivation, and a significant increase in TP and AP during SM cultivation, effectively promoted crop yield. Furthermore, continuous PT application significantly enriched phosphorus (P)-soluble functional bacteria, such as Actinomycetes and Chloroflexota, and enhanced the stability of bacterial-fungal cross-boundary networks. In summary, optimal acidity levels and favorable soil texture improved soil quality, consequently increasing corn and potato yields. This study reveals for the first time that PTs can substantially increase crop production via a synergistic mechanism involving acid-base balance, structural improvement, and microbial activation. Not only does this provide a novel strategy for rapidly improving acidic soils, but it also establishes a solid theoretical and technical foundation for utilizing PT resources. Full article

A multi-factor analysis of cultivar, biofertiliser, and growing season was conducted to optimise lettuce agronomic and quality traits in diverse soil conditions. The goal was to identify soil differences and offer practical recommendations to improve lettuce traits and quality for farmers and the processing industry. The study employed a complete block design with four treatments, three involving biofertilisers, applied to six lettuce cultivars grown in two contrasting soil types- Mollic Gleysol (Calcaric)-GL and Hortic Anthrosol (Terric, Transportic)-AT, across three consecutive greenhouse seasons (autumn, winter, and spring). Biofertilisers were applied to the soil before transplanting and foliarly during the growing cycle, with four of the following treatments: control (no fertilisation), a fertiliser containing beneficial microorganisms, a Trichoderma-based fertiliser, and a combination of both. In GL soil, all biofertiliser treatments increased rosette height, leaf number, and stem length, whereas in AT soil, all morphological parameters declined significantly. The green cultivars ‘Aquino’ and ‘Kiribati’ showed superior morphological performance, particularly in spring and winter. Rosette fresh weight, a key indicator of plant biomass, reached 236.4 g in ‘Aquino’ grown in GL soil, and 208.6 g in ‘Kiribati’ grown in AT soil. Dualex™ leaf sensor measurement indicated that ‘Aquino’ exhibited the highest nitrogen balance index (NBI), while the red cultivar ‘Gaugin’ recorded the highest chlorophyll, flavonoid, and anthocyanin contents. Combined fertilisers increased NBI by 6.3% and chlorophyll by 6.8% in GL soil. Trichoderma fertiliser alone raised NBI by 6.8% in GL soil, whereas in AT soil, plants accumulated more flavonoids and anthocyanins (by 9.2% and 8.5%). Optical parameters were highest in autumn. The three-factor experiment demonstrated that cultivar, biofertiliser, and growing season significantly influenced the majority of measured traits. Correlation analysis revealed that rosette fresh weight was positively associated with NBI but negatively correlated with quality-related traits. Based on these findings, cultivars ‘Aquino’, ‘Kiribati’, and ‘Gaugin’ are recommended for both farmers and the processing industry to improve lettuce production quantity and quality. Overall, cultivar, biofertiliser, and season strongly influenced the measured parameters, underscoring the importance of tailoring biofertiliser application to soil type and season to achieve optimal production outcomes. Full article

Tea plantations are one of the most intensive land-use systems in subtropical China, but the long-term effects on soil microbial functioning remain insufficiently understood. This study combined extracellular enzyme activity, ecoenzymatic stoichiometry, and partial least squares path modeling (PLS-PM) to assess the impacts of forest-to-tea conversion and plantation age on microbial nutrient acquisition and metabolic limitations. The results showed that tea plantations had significantly higher activities of carbon (C)-, nitrogen (N)-, and phosphorus (P)-acquiring hydrolases compared to adjacent pine forests, and oxidase activity increased significantly with plantation age, reaching a fivefold higher level in the oldest plantation. Soil acidification, decreased soil organic carbon, and shifts in microbial composition (decline in bacteria and actinomycetes, increase in fungi) were the main drivers of these changes. The study indicates that tea planting intensifies microbial limitations on carbon and phosphorus and shifts microbial metabolism toward oxidative pathways, which may destabilize soil carbon pools and reduce long-term fertility. These findings highlight the importance of balanced nutrient management in tea plantation practices. However, the study is limited by the short duration of field sampling. Future research should focus on long-term monitoring to better understand the sustained impacts of tea cultivation on soil microbial functions and explore the role of different management practices in mitigating these effects. Full article

Sustainable soil management is crucial for balancing agricultural productivity and soil health in Mollisols under long-term tillage systems. This study evaluated the effects of no-tillage (NT), minimum conservation tillage (MCT), and conventional tillage (CT) on soil properties and maize yield in an irrigated Mollisol in Chapingo, Mexico, over 9, 22, and 25 yr, using a Latin square design with three replications. MCT significantly enhanced soil organic carbon (SOC), total nitrogen (TN), available phosphorus (AP), and exchangeable potassium (EK) compared to NT and CT, achieving the highest maize grain yield (7.21 t ha⁻¹). NT exhibited the greatest SOC and EK in the surface layer. Physical properties, such as bulk density and porosity, remained stable across systems, reflecting Mollisol resilience. Although MCT optimized fertility and productivity, nutrient declines from 2021 to 2024 highlight the need for adaptive management strategies to sustain long-term productivity, supporting global soil conservation and sustainable agriculture goals. Full article

Zeolitic imidazolate frameworks (ZIFs) can provide fascinating stereo morphology and tunable metal active sites, which plays an important role in the synthesis of various catalytic materials. However, it is still a problem to make use of these advantages to design efficient hydrogen evolution reaction (HER) catalysts. Herein, we use covalent coordination strategy to synthesize bimetallic Co_xZn_1−x(2-MeIM)₂ precursors with regular dodecahedral structures for providing uniform active sites and stable carbon skeleton. Furthermore, the ratio of Co and Zn atoms was optimized to balance the electron density and give full play to the synergistic catalytic effect. And then, the subsequent high temperature annealing process is used to construct the amorphous carbon layer, which can improve the overall stability of the material. The gas phase phosphating process realizes the transformation from ZIF material to metal phosphide resulting in enhanced hydrogen evolution activity. Finally, the optimized amorphous nitrogen-doped carbon (NC)-coated Zinc-doped cobalt phosphide (Zn_0.17Co_0.83P@NC) requires only 237.60 mV to reach the current density of 10 mA cm⁻² in alkaline medium, which is 223.22 mV lower than that of CoP, and has a stability of up to 18 h. This work provides a reference for the rational design of efficient and stable compound electrocatalysts for alkaline hydrogen evolution based on the bimetallic ZIF as a precursor. Full article

Microbial metabolism is intricately governed by thermodynamic constraints that dictate energetic efficiency, growth dynamics, and metabolic pathway selection. Previous research has primarily examined these principles under carbon-limited conditions, demonstrating how microbes optimize their proteomic resources to balance metabolic efficiency and growth rates. This study extends this thermodynamic framework to explore microbial metabolism under various non-carbon nutrient limitations (e.g., nitrogen, phosphorus, sulfur). By integrating literature data from a range of species, it is shown that growth under anabolic nutrient limitations consistently yields more negative Gibbs free energy ($\Delta G$) values for the net catabolic reaction (NCR) per unit of biomass than carbon-limited scenarios. The findings suggest three potentially complementary hypotheses: (1) proteome allocation hypothesis: microbes favor faster enzymes to reduce the proteome fraction used for catabolism, thus freeing proteome resources for additional nutrient transporters; (2) coupled transport contribution hypothesis: the more negative $\Delta G$ of the NCR may in part stem from the increased reliance on ATP-coupled or energetically driven transport mechanisms for nutrient uptake under limitation; (3) bioenergetic efficiency hypothesis: microbes prefer pathways with a more negative $\Delta G$ to enhance the cellular energy status, such as membrane potentials or the ATP/ADP ratio, to support nutrient uptake under anabolic limitations. This integrative thermodynamic analysis broadens the understanding of microbial adaptation strategies and offers valuable insights for biotechnological applications in metabolic engineering and microbial process optimization. Full article

Climate change poses a major challenge for wine production in semi-arid regions, where grape ripening frequently leads to excessive sugar accumulation and reduced acidity. This study evaluated the combined effect of cold pre-fermentative maceration (PM) and the use of non-Saccharomyces yeasts (Lachancea thermotolerans and Torulaspora delbrueckii) on the composition and sensory properties of Cayetana Blanca wines. Pre-fermentative maceration increased titratable acidity by 0.5 g/L and yeast-assimilable nitrogen by 28 mg/L, creating more favorable conditions for the metabolic activity of non-Saccharomyces species. Wines fermented with L. thermotolerans—especially in sequential inoculation with S. cerevisiae after PM—showed the highest acidity and lactic acid content (2 g/L), together with 1% v/v lower ethanol and 1 g/L higher glycerol than the control. These wines were perceived as fresher and better balanced, despite a moderate decrease in fruity esters such as ethyl hexanoate, ethyl octanoate, and isoamyl acetate. Cluster analysis confirmed that non-Saccharomyces fermentations developed distinct compositional profiles only when combined with PM. Overall, the PM + L. thermotolerans + S. cerevisiae treatment achieved the most favorable balance between acidity, ethanol, and sensory freshness. This approach provides a sustainable and readily applicable method to enhance acidity and freshness in white wines from warm-climate regions. Full article

Coconut yield and quality are significantly affected by multiple female inflorescences (MFF), which disrupt flower differentiation balance. To elucidate the molecular mechanisms, we compared MFF with normal female inflorescences (NFF) using phenotypic, morphological, physiological, and multi-omics approaches. The results revealed that MFF exhibited altered flower structures. MFF showed elevated iron (Fe), nitrogen (N), sulfur (S), potassium (K), calcium (Ca), zinc (Zn), proline (Pro), catalase (CAT), malondialdehyde (MDA), abscisic acid (ABA), and jasmonic acid (JA), but reduced molybdenum (Mo), soluble sugar (SS), soluble protein (SP), superoxide dismutase (SOD), peroxidase (POD), indole acetic acid (IAA), zeatin riboside (ZR), and gibberellic acid (GA). We detected 445 differentially expressed genes (DEGs) mainly enriched in ABA, ETH, BR, and JA pathways in MFF compared to NFF. We identified 144 differentially accumulated metabolites (DAMs) primarily in lipids and lipid-like molecules, phenylpropanoids and polyketides, as well as organic acids and derivatives in the comparison of MFF and NFF. Integrated analysis linked these to key pathways, e.g., “carbon metabolism”, “carbon fixation in photosynthetic organisms”, “phenylalanine, tyrosine, and tryptophan biosynthesis”, “glyoxylate and dicarboxylate metabolism”, “glycolysis/gluconeogenesis”, “pentose and glucuronate interconversions”, “flavonoid biosynthesis”, “flavone and flavonol biosynthesis”, “pyruvate metabolism”, and “citrate cycle (TCA cycle)”. Based on our results. the bHLH137, BHLH062, MYB (CSA), ERF118, and MADS2 genes may drive MFF formation. This study provides a framework for understanding coconut flower differentiation and improving yield. Full article

Excessive nitrogen addition in farmland on the Loess Plateau reduces soil quality and endangers the atmospheric environment. We designed an experiment to investigate the effects of different nitrogen application rates on the soil physicochemical properties and microbial diversity of spring wheat fields on the Loess Plateau, aiming to identify the optimal nitrogen application rate and avoid the detrimental effects of excessive nitrogen addition. A field experiment was conducted from 2022 to 2023 with four nitrogen (N) application rates (0, 55, 110, and 220 kg·N·ha⁻¹·y⁻¹). This study aimed to assess the changes in soil properties, nutrient contents, enzyme activities, and bacterial community structure. The results showed that increasing N application generally enhanced soil bulk density, nitrate nitrogen (NO₃⁻-N), ammonium nitrogen (NH₄⁺-N), and microbial biomass nitrogen (MBN) (p < 0.05). In contrast, soil water content initially increased and then decreased. Soil organic carbon and total nitrogen rose markedly with higher N inputs, particularly in the 0–20 cm layer, whereas total phosphorus was less affected. Nitrogen addition stimulated soil enzyme activities (protease, urease, nitrate reductase, and nitrite reductase), though excessive input (220 kg·N·ha⁻¹·y⁻¹) produced inhibitory effects. Actinobacteria (relative abundance: 29–35%) and Proteobacteria (relative abundance: 14–22%) were the dominant phyla in all treatments. Alpha diversity peaked at low nitrogen input (55 kg·N·ha⁻¹·y⁻¹), while high N level reduced evenness and species richness (p < 0.05). Principle Coordinate Analysis (PCoA) revealed that both N application and soil depth shaped microbial community assembly, with deeper layers (20–40 cm) being more sensitive to N input. Correlation analysis indicated that soil moisture, bulk density, and C:N:P stoichiometry were key drivers of bacterial community variation. Overall, moderate nitrogen input (110 kg·N·ha⁻¹·y⁻¹) improved soil fertility and supported microbial functionality, whereas excessive application degraded soil structure and reduced biodiversity. These findings highlight the need for balanced N management strategies in rain-fed agriculture of the Loess Plateau to sustain both productivity and ecological stability. Full article

Nitric oxide (NO), a reactive nitrogen species (RNS), plays a role in multiple biological functions and signal transduction. However, the mechanisms by which NO counteracts stress tolerance in microbes have been poorly explored. In addition, the decomposition of salty food waste poses a significant challenge for food-degrading microbes. Therefore, we investigated how S-nitrosocysteine (CysNO) affects the cellular salt stress response of Burkholderia vietnamiensis TVV75, a strain isolated from a commercial food waste composite. Under the additional 2% NaCl treatment, increased reactive oxygen species (ROS) inhibited bacterial cell growth and viability. In contrast, CysNO treatment alleviated the cellular ROS levels and growth inhibition by augmenting the superoxide dismutase (SOD) and catalase (CAT) activities. CysNO supplementation also promotes the nitrate reduction pathway in B. vietnamiensis TVV75 under salt stress, suggesting NO-mediated nitrogen metabolism for microbial adaptation to salt stress. Furthermore, CysNO restored the intracellular lipid-degrading lipase enzyme activities, which were compromised by salt stress alone. This restoration was accompanied by a concentration-dependent increase in the relative expression of the lipA (lipase A) and ELFPP (esterase lipase family protein) genes. These results suggest that external NO supplementation can regulate redox balance, nitrate reduction, and lipase activity to maintain microbial cell growth in high-salt environments, pinpointing a NO-dependent salt stress adaptation strategy for salt-sensitive microbes involved in food waste decomposition. Full article