Search Results (802)

The probiotic efficacy of H. coagulans relies on the bile salt tolerance of its vegetative cells, yet direct evidence linking this trait to intestinal colonization remains limited. This study integrated phenotypic screening, in vitro gastrointestinal simulation, in vivo colonization assays, and comparative genomics to address this gap. Among 50 strains, two highly bile salt-tolerant isolates (ATCC 7050 and Idrc019) were identified. In vitro assays using a simulated gastrointestinal model demonstrated that the spores of tolerant strains exhibited a significantly higher germination rate in the intestinal phase. Subsequently, in vivo time-course experiments demonstrated that tolerant strains exhibited superior intestinal proliferation and modulated the gut microbiota by enriching beneficial genera such as Blautia. Comparative genomic analysis revealed five variable genes associated with bile salt tolerance. Notably, BF29_941 (encoding a pilus assembly protein) was significantly upregulated under bile salt stress, suggesting a potential role in cell aggregation as a tolerance mechanism. These findings establish bile salt tolerance as a critical determinant of intestinal colonization in H. coagulans. Full article

Frequent agricultural and pastoral activities in northern China’s agro-pastoral ecotone have resulted in severe soil salinization. Although phytoremediation is currently the recommended remediation strategy, plant growth is often hindered by microbial deficiencies, nutrient limitations, and high salt content. Arbuscular mycorrhizal fungi (AMF) are prevalent in saline soils and have been shown to facilitate the growth of various forage grasses. However, highly efficient “AMF strain–leguminous forage grass” remediation systems are currently lacking in this area. This study examined the impact of nine AMF strains sourced from the Bank of Glomeromycota in China (BGC) on the growth and salt tolerance mechanisms of Medicago sativa and Astragalus adsurgens via pot experiment. The results showed that all the strains, except Funneliformis mosseae BGC NM04A (Fm-2), exhibited significant promotion of the growth of both leguminous forage species. Specifically, the growth of M. sativa increased by 157% to 354%, and that of A. adsurgens increased by 15.2% to 252%. The impact of different strains on plant-soluble sugar and protein content was found to vary, with Rhizophagus intraradices BGC BJ09 (Rin) and Rhizophagus irregularis MUCL 43194 (Rir-1) having particularly pronounced effects. Most of the AMF strains enhanced the uptake of phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) in the shoots of both plant species. Additionally, all strains except for Fm-2 exhibited a significant increase in the K⁺/Na⁺ ratio in M. sativa shoots. In contrast, only Claroideoglomus etunicatum BGC GZ03C (Ce-1) and Rir-1 demonstrated a substantial increase in the K⁺/Na⁺ ratio in A. adsurgens. Following a comprehensive assessment, several highly effective combinations were identified: M. sativa in combination with Ce-1, F. mosseae BGC HUN01A (Fm-1), or Rir-1; and A. adsurgens with Rir-1 or Fm-1. These “forage–AMF strain” combinations have been demonstrated to alleviate salt stress by enhancing mycorrhizal effects, regulating ion homeostasis, and optimizing osmotic regulatory substances. Our findings have clarified the intraspecific and interspecific differences in AMF in mitigating salt stress, emphasizing the potential of AMF as a sustainable strategy to improve the stress resistance and productivity of leguminous forages in the saline agro-pastoral ecotone. Full article

Understanding interactions between cations and DNA is essential for elucidating the structural dynamics of this fundamental biomolecule. While B-DNA is well known to dominate in long genomic DNA under physiological ionic conditions, its stability in very short DNA fragments—particularly in dilute solutions and in crude oligonucleotide preparations—has remained largely unexplored. Previous spectroscopic studies have primarily focused on long DNA, highly purified oligonucleotides, or high-salt environments, where collective polyion effects dominate. In contrast, the present results demonstrate that even in the absence of chain overlap and under low-salt conditions, Mg²⁺ ions efficiently stabilize the B-form by screening phosphate–phosphate electrostatic repulsion at the intrachain level. The ability to induce an A-to-B transition in crude, ultra-short DNA fragments highlights the fundamental role of divalent counterions in governing DNA conformation and establishes a lower bound for the length scale at which B-DNA can be stabilized. These findings are particularly relevant for dilute biological systems, fragmented DNA samples, and analytical protocols where short DNA fragments and low ionic strength are unavoidable. Full article

Saline–alkali soil salinization is a global ecological crisis affecting 932 million hectares of land worldwide, posing a severe threat to food security and ecological sustainability. Traditional improvement methods, such as chemical amendments and hydraulic engineering, are limited by high costs and environmental risks, whereas microbial amendments have emerged as eco-friendly and sustainable alternatives due to their ability to regulate soil microenvironments and enhance plant stress resistance. However, a comprehensive synthesis of their core mechanisms, global application progress, and regional adaptation characteristics is still lacking, hindering the standardization and promotion of related technologies. This review, conducted in accordance with PRISMA guidelines, systematically synthesizes 112 core studies (1990–2025) retrieved from Web of Science, Scopus, and CNKI databases, focusing on three core research objects: salt-tolerant microbial communities in saline–alkali soils (dominant taxa, functional genes, metabolic characteristics), development and optimization of microbial amendments (strain screening, composite formulation, carrier selection), and mechanisms and application effects of microbial remediation (soil–plant–microbe interactions, physicochemical improvement, crop growth promotion). Key findings include the following. (1) Dominant microbial taxa (e.g., Proteobacteria, Actinobacteria) exhibit region-specific adaptation strategies, with salt tolerance thresholds and functional characteristics varying by soil type (coastal vs. inland saline–alkali soils). (2) Composite microbial amendments, especially those combined with biochar or organic fertilizers, achieve synergistic effects in desalination, alkali reduction, and fertility improvement. (3) Core mechanisms involve organic acid-mediated pH regulation, EPS-driven ion adsorption, and plant hormone-induced stress tolerance. (4) Microbial remediation technologies have been successfully applied globally (e.g., China, Africa, Americas), resulting in average crop yield increases of 15–42% and soil salinity reductions of 30–50%. This review provides a standardized technical framework for the development and application of microbial amendments, offers theoretical support for region-specific remediation strategies, identifies key challenges (e.g., strain stability, cost control) and future research directions (e.g., gene-edited strains, smart monitoring integration), and thus facilitates the industrialization and large-scale promotion of microbial remediation technologies to address global saline–alkali soil issues. Full article

The widespread application of road deicing salts in northern regions has led to elevated salinity in roadside soils and adjacent watersheds. Phytoremediation offers a cost-effective and sustainable approach for mitigating salt contamination, but its success depends on utilizing plant species that can both tolerate and remove salt under roadside conditions. To systematically identify high-potential candidates from the large inventory of salt-tolerant plants in North America, we developed a quantitative decision matrix incorporating criteria related to ecological safety, establishment potential on disturbed soils, aboveground biomass production, biomass use-value, and salt uptake capacity. Thirteen of the highest-ranked species were subsequently evaluated for sodium (Na⁺) and chloride (Cl⁻) uptake in a controlled greenhouse study under saline and non-saline conditions. The greatest total salt uptake was observed in common sunflower (Helianthus annuus) (35.6 mg Na⁺ and 100.2 mg Cl⁻ plant⁻¹) and pitseed goosefoot (Chenopodium berlandieri) (18.6 mg Na⁺ and 76.0 mg Cl⁻ plant⁻¹), while perennial species including tall fescue turfgrass (Lolium arundinaceum), showy goldenrod (Solidago speciosa), and weeping alkaligrass (Puccinellia distans) also demonstrated substantial uptake combined with greater long-term suitability for roadside management. Overall, this study presents a quantitative framework for phytoremediation species selection and provides experimental evidence supporting both annual and perennial species for mitigating deicing salt contamination through environmentally sustainable, low-input roadside management strategies. Full article

The western region of the Tarim Basin is a typical deep and ultra-deep oil and gas reservoir with complex geological conditions in China. This area includes a thick salt–gypsum layer, high-pressure brine layers, and other formations with high pressures and a complex pressure system. These geological features present challenges such as a high risk of drilling fluid contamination by formation fluids, the deep burial of subsalt reservoirs, high temperatures, and difficulty in designing drilling fluids. In this paper, by systematically screening and optimizing key additives, a diesel oil-based drilling and completion fluid system resistant to 220 °C ultra-high temperatures with a density of 2.60 g/cm³ was developed. The overall performance was evaluated. Utilizing an independently developed high-temperature emulsifier (BZ-PSE), an organically modified lithium silicate viscosity modifier (BZ-CHT), and compounded fluid loss reducers (BZ-OLG/BZ-OSL), the system maintained excellent rheological stability (yield point > 4.3 Pa) and filtration control capacity (HTHP fluid loss < 4.8 mL) even after aging at 220 °C. The system demonstrated a resistance to contamination by 30–50% composite brines, 15% salt–gypsum cuttings, and 10% cement, proving its capability to effectively handle extremely thick mud shale, salt–gypsum layers, and high-pressure brine. Field tests were conducted in wells GL 3C, DB X, Boz 13X, and Boz 3X. The results indicated that the high-temperature, high-density diesel oil-based drilling fluids and completion fluids can effectively address the technical challenges posed by wellbore instability in thick salt–gypsum layers, high-pressure brine invasion, and performance degradation under ultra-high temperature conditions, providing reliable technical support for the safe and efficient drilling of similar complex formations. Full article

Salinity stress has become an increasingly critical challenge for agricultural production, especially for rice, a staple crop that feeds over 50% of the world population but is extremely sensitive to salt stress. In this study, ten rice genotypes were treated with three salinity levels (0, 50, and 100 mM NaCl) to investigate the effects of salt stress on rice, and this data was then used to build regression models that describe plant growth responses as a function of stomatal conductance (Gs), chlorophyll content (SPAD), and shoot K⁺ and Na⁺ contents—parameters that can be used for high-throughput screening of rice plants for salinity stress tolerance. In silico modeling results showed that the best model for predicting shoot dry weight (SDW) was based on Gs, SPAD, and shoot K⁺ content, while shoot Na⁺ content had no significant influence on biomass accumulation. These findings challenge the traditional focus on Na⁺ exclusion from the shoot as a breeding target and suggest that enhancing K⁺ retention and optimizing stomatal development and operation may be a more effective strategy for improving rice growth under salinity. Overall, this study highlights the need to reconsider key genetic targets involved in the regulation of Gs, K⁺ homeostasis, and chlorophyll maintenance to better face the challenges caused by salinity in future climate scenarios. Full article

Umami taste in lager beer not only determined body fullness and the backbone of aftertaste, but also affected the controllability and interpretability of flavor expression across the entire brewing process. Based on stage-wise sampling, peptidomic profiles were established on wort fermentation day 0, day 1, day 3, and day 9. A total of 25,592 peptides were identified by reversed-phase liquid chromatography–quadrupole time-of-flight mass spectrometry (RPLC-QTOF-MS). Molecular informatics screening was performed using UMPred-FRL (a feature representation learning-based meta-predictor for umami peptides) and TastePeptides-Meta (a one-stop platform for taste peptides and prediction models), yielding 7255 potential umami peptides. From these, 145 peptides were further selected for molecular docking. In addition, 6 representative umami peptides were selected for receptor-level validation and structural analysis. Mechanistically, the umami receptor taste receptor type 1 member 1/taste receptor type 1 member 3 (T1R1/T1R3) belonged to class C G protein-coupled receptor (GPCR) and relied on the extracellular Venus flytrap (VFT) domain for ligand capture. Ligand-induced VFT conformational convergence transmitted changes to the transmembrane region and triggered signal transduction. Docking and energy decomposition indicated that the ionic group primarily contributed to orientation and anchoring. Salt-bridge or hydrogen-bond networks were formed around Lys228, Arg240, Glu206, Asp210, Asn141, and Gln138, thereby reducing conformational freedom. Meanwhile, hydrophobic side chains obtained major binding gains within a hydrophobic microenvironment formed by Val135, Ile137, Leu165, Tyr166, Trp78, and His79. These results reflected a synergistic mode in which charge pairing enabled positioning and hydro-phobic complementarity promoted VFT closure. To experimentally confirm sensory relevance, 6 representative peptides were individually spiked into 4 brewing-stage beer samples, which produced a clear stratification pattern across stages. Notably, peptides with favorable docking-derived binding propensity did not necessarily enhance umami perception, and several longer peptides showed persistent negative sensory shifts, supporting that binding affinity alone could not be treated as a proxy for perceived umami in the beer matrix. At the node level, the cumulative abundance of umami peptides showed a significant positive correlation with umami scores, with a Pearson correlation coefficient of r = 0.963 and p = 0.037. This result indicated good linear consistency between umami peptide content and the upward shift in umami taste in lager beer. Umami peptide clusters were further proposed as a more appropriate functional unit, and an umami peptide cluster database spanning the full process was constructed. This database provided a reusable resource for process control and flavor prediction. Full article

Land desertification poses a major ecological challenge and threatens agricultural productivity. This study investigated the seed endophytic microbiomes of desert plants as a potential resource for mitigating salt stress in crops. Using high-throughput sequencing, we characterized the bacterial and fungal communities within seeds of 12 desert plant species. Dominant taxa included Firmicutes (particularly Bacillus), Bacteroidota, Proteobacteria, Ascomycota, and Basidiomycota. Culturable bacteria were subsequently isolated from Haloxylon ammodendron (C.A.Mey.) Bunge (HB) and Hedysarum scoparium Fisch. & C.A.Mey. (HSA) seeds. These isolates were screened for plant growth-promoting (PGP) traits and tolerance to salt (NaCl) and alkali (NaHCO₃). Selected strains, including the high indole-3-acetic acid (IAA)-producing Bacillus sp. HB-4, were used to inoculate wheat (Triticum aestivum L.) under 150 mM NaCl or 150 mM NaHCO₃ stress. Inoculation with strain HB-4 significantly improved wheat growth under stress. This improvement was associated with increased chlorophyll and proline content, enhanced activities of the antioxidant enzymes catalase and peroxidase, and reduced levels of malondialdehyde, a marker of oxidative damage. Our results demonstrate that desert plant seeds harbor taxonomically distinct and functionally resilient endophytes. The successful application of a desert-adapted Bacillus strain to alleviate salt stress in wheat highlights the potential of such microbiomes as a novel source of inoculants for sustainable agriculture in saline-affected regions. Full article

This work provides a systematic experimental study for the electrochemical desalination of saline water using an electrospun permselective polyvinylidene difluoride (PVDF) membrane. Several nano additives were initially screened during membrane development; however, only the materials that demonstrated stable dispersion, reproducible membrane formation, and consistent electrochemical behaviour, namely graphene oxide (GO) and carbon nanotubes (CNTs) were selected for full analysis in this study. Accordingly, the study focuses on pure PVDF, PVDF/GO, and PVDF/CNTs membranes integrated with an alternating Ag/AgCl electrode system. The silver electrode is prepared by spray-coating of silver nanoparticles on high surface carbon cloth, whereas the AgCl electrode was prepared electrochemically from the Ag electrode using a three-electrode electrochemical cell. The electrochemical behaviour of various modified electrodes (bare carbon cloth, Ag/carbon cloth, Ag/nafion/carbon black/PVDF, and Ag/nafion/carbon cloth) was evaluated using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and X-Ray Diffraction (XRD). The electrode prepared using Nafion and PVDF as binders with carbon black as conductive additive exhibited the highest current response and lowest charge-transfer resistance. When coupled with this optimized electrode, the PVDF/GO membrane delivered the best desalination performance, achieving an ion removal efficiency of 68%, a salt adsorption capacity (SAC) of 775.40 mg/g, and a specific energy consumption (SEC) of 16.17 kJ/mole values superior to those reported in the literature. Full article

Synthetic gypsum (SG) is produced in massive quantities, yet hazardous impurities limit its reuse. This review summarized the impurity types in various SGs and the corresponding removal methods. Physical methods, such as washing, screening, magnetic separation, and others, exploit solubility and size/density differences to remove soluble salts and particulates. Chemical methods, including acid leaching, precipitation/solidification, and so on, can dissolve or immobilize phosphates, fluorides, and heavy metals. Flotation utilizes the differences in the physicochemical properties of solid surfaces to remove insoluble impurities. The thermal treatment is mainly used to decompose organics and improve whiteness. Microbial methods achieve environmentally friendly cleanup through metabolic leaching or microbially induced carbonate precipitation. The phase-transformation method is a recently developed method that can achieve synergistic effects of deep impurity removal and high-value utilization by reconstructing gypsum crystals to release co-crystallized impurities. Most impurity-removal methods target only a single type of impurity. At present, purifying SG requires a combination of multiple methods, which is not recommended from a cost perspective. Subsequent research on removing impurities from SG should focus on simultaneously removing multiple major impurities in a single process, as well as the synergistic effects between impurity removal and the high-value utilization of gypsum. Full article

This study investigated the generation of α-glucosidase inhibitory peptides from whey protein fermented by the marine-derived probiotic Lacticaseibacillus casei DS31 (isolated from the intestinal microbiota of the large yellow croaker, Larimichthys crocea) and assessed their potential for practical glycemic management. Fermentation markedly increased inhibitory activity, with the freeze-dried crude supernatant exhibiting an IC50 of 2.115 mg/mL. Activity was further enriched through stepwise purification: ultrafiltration (<3 kDa) improved potency (IC50 = 1.206 mg/mL), and subsequent Sephadex (crosslinked dextran) G-15 gel filtration yielded a more active E fraction (IC50 = 1.145 mg/mL). LC–MS/MS characterized 19 peptides, and integrated in silico screening (PeptideRanker combined with molecular docking) highlighted GEPGPEGPAG as a leading candidate, showing a more favorable predicted binding energy (−82.50 kcal/mol) than the positive control acarbose (−69.31 kcal/mol). Docking analysis suggests that GEPGPEGPAG may inhibit α-glucosidase by forming a stable network of hydrogen bonds, salt bridges, and hydrophobic interactions within the catalytic pocket. Overall, DS31-fermented whey and its enriched fractions show promise as functional ingredients for postprandial glycemic control. Full article

Soil salinization threatens crop production; however, in multi-crop field systems, evidence for the effectiveness of waste biomass-functional microorganism composite amendments remains limited. Here, we developed a composite microbial soil conditioner (F2) using pine needles and crushed corn cobs as carriers combined with salt-tolerant strains Bacillus subtilis (K1), Azotobacter chroococcum (Y1), and Bacillus gelatinus (J3) to remediate moderately saline-alkali soil from central Gansu (pH 8.36 ± 0.18; EC 1658 ± 55.24 μS·cm⁻¹). Saturation screening identified an optimal carrier ratio of pine needles:corn cobs = 1:2 and an inoculum ratio of K1:Y1:J3 = 1:2:1. In pot experiments, F2 increased soil organic matter and water-holding capacity, enhanced alkaline phosphatase, urease, and sucrase activities, and significantly reduced soil pH and EC. Maize seedling height and chlorophyll content increased by 53.87% and 38.88%, respectively. Amplicon-based microbiome profiling indicated enrichment of beneficial microbial taxa and strengthened primary metabolic functions under F2. Field validation across five crops (flax, potato, edible sunflower, sorghum, and maize) showed consistent growth and yield-related improvements. Overall, these results demonstrate that the biomass–microbe composite amendment effectively alleviates saline-alkali constraints by jointly improving soil properties, microbial functions, and crop performance. Full article

The rise of multidrug-resistant enteric pathogens and increased demand for antibiotic alternatives have intensified efforts to find reliable, safe, and effective probiotics. This study reports the isolation, characterization, and assessment of the probiotic potential of five Enterococcus strains isolated from the feces of healthy goats aged 7–9 months raised under conventional management. Following an initial screening of 57 lactic acid bacteria, 5 isolates (Enterococcus faecium, E. hirae, E. faecalis, Enterococcus sp., and Streptococcus lutetiensis) were chosen based on their catalase-negative, non-motile, and non-hemolytic characteristics, in addition to their high tolerance to gastric (pH 2.0) and intestinal (pH 8.0, 0.3–1.5% bile salt) stress. In simulated gastric juice, survival rates reached 89.05% (E5) and 85.03% (E3), while in intestinal juice, survival peaked at 78.01% (E4). All strains thrived in 4% NaCl and maintained at least 8 Log₁₀ CFU/mL after 12 h of exposure to 1.5% porcine bile salt. Cell surface hydrophobicity (0.78–93.85%) and auto-aggregation (23–91%) properties were strain-dependent, but exceeded the thresholds required for efficient gut colonization. Co-aggregation assays demonstrated over 45% binding with E. coli and S. typhimurium, suggesting a strong potential to displace pathogens. Cell-free supernatants created inhibition zones measuring 15.02 mm against E. coli and 11.04 mm against S. flexneri, while maintaining activity against methicillin-resistant S. aureus (MRSA). Antibiotic testing indicated that all strains were sensitive to ciprofloxacin and florfenicol. No β-hemolysis or mobile resistance genes were found, supporting the initial safety findings. This study reveals that Enterococcus isolates from goats display a unique combination of gastrointestinal survivability and broad-spectrum antipathogenic activity and, therefore, are promising candidates for the development of next-generation probiotic strains for use in livestock (and, potentially, humans). Further in vivo validation and genome-based safety assessments are warranted. Full article

Protective cultures are an increasingly industrially relevant biopreservation tool for meat and meat products, responding to simultaneous demands for microbiological safety, extended shelf life, and reduced reliance on synthetic preservatives within clean-label frameworks. This review summarizes current advances in protective cultures applied to meat systems, with emphasis on technological functions, efficacy boundaries, and safety-related due diligence. We discuss the dominant inhibitory mechanisms of lactic acid bacteria and related protective taxa—acidification, competitive exclusion, and antimicrobial metabolites (including bacteriocins)—and highlight why performance is strongly strain- and matrix-dependent under realistic storage conditions. Practical applications are reviewed across raw meats (spoilage delay under refrigeration and vacuum/MAP) and processed or ready-to-eat products, where post-processing surface application emerges as a critical control point for limiting Listeria monocytogenes outgrowth during chilled storage. Key implementation constraints include technological compatibility and sensory neutrality, which are influenced by product buffering capacity, salt content, available fermentable substrates, packaging atmosphere, and temperature. From a safety perspective, we synthesize evidence on antimicrobial resistance in food-associated cultures and outline contemporary qualification strategies combining phenotypic susceptibility testing with genome-based screening to exclude acquired and potentially transferable resistance determinants. Overall, protective cultures should be viewed as a targeted hurdle integrated into holistic preservation systems rather than a standalone substitute for hygiene and process control. Full article