Search Results (273)

The present study investigates the manufacturing and characterization of poly(lactic acid) (PLA)-based composites with raw and treated Poaceae, with loadings of 5, 10, and 20% wt. Before composite fabrication, the lignocellulosic fillers were analyzed using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and microscopy to assess their chemical composition, thermal stability, and morphological features. Composites were prepared by melting PLA in a molten state with fillers, followed by injection molding. Comprehensive characterization of the obtained composites included microscopic analysis, melt flow index (MFI) testing, and differential scanning calorimetry (DSC), as well as mechanical tests (tensile and bending tests, impact test). The addition of Poaceae fibers to the PLA matrix significantly affected the mechanical and rheological properties of the composites. Incorporating 5% of cooked or alkalized fibers increased the flexural strength by 57% and 54%, respectively, compared to neat PLA. The modulus of elasticity for the composite with 20% alkalized fibers increased by as much as 35%. The fibers acted as nucleating agents, reducing the cold crystallization temperature (T_cc) by up to 15.6 °C, while alkaline residues contributed to an increased melt flow index (MFI). The conducted research provides a valuable basis and insights into the design of sustainable bio-based composites. Full article

Hybrid systems combining animal and plant proteins are promising for developing sustainable, high-protein foods. However, structural incompatibility between proteins like casein and pea protein hinders the formation of stable systems such as gels. This study explores pH-shifting (alkalization at pH 12 followed by neutralization) as an innovative strategy to improve pea protein functionality and compatibility in hybrid gels. Modified pea protein showed increased solubility, reduced particle size, higher zeta potential, and decreased intrinsic fluorescence intensity, indicating conformational changes and exposure of buried tryptophan residues. These structural changes influenced gel behavior depending on the protein ratio (casein/pea—80:20, 50:50, 20:80). Gels with higher pea content showed increased hardness and water-holding capacity, while in casein-rich gels, hardness decreased, likely due to altered protein–protein interactions. This is the first study to systematically apply pH-shifting to enhance the compatibility between pea protein and casein in high-protein gels, integrating structural and functional analyses. The results demonstrate the potential of pH-shifting as a sustainable and effective approach for improving plant protein performance in hybrid formulations. Full article

Background: Aneratrigine, a potent selective Nav1.7 inhibitor, faced challenges in developing a clinically viable oral formulation due to its poor aqueous solubility in acidic gastric conditions (0.06 mg/mL at pH 1.2), leading to limited bioavailability in Phase 1 studies. Methods: To address this, a capsule formulation containing sodium bicarbonate (NaHCO₃) was developed to enhance dissolution via in situ pH modulation. However, production-scale wet granulation led to stability issues, such as capsule content discoloration and excessive degradant formation, attributed to NaHCO₃ decomposition under thermal and moisture stress. This raised the content pH and triggered degradation products not seen in initial compatibility tests. Consequently, dry granulation was adopted to minimize heat and moisture exposure. Results: The dry granulation process proved scalable, maintaining chemical integrity across laboratory (1.5 kg), pilot (5.4 kg), and commercial (25.9 kg) batches. The optimized formulation showed enhanced stability (total impurities < 0.05%) and improved dissolution (>80% at 30 min, pH 4.0). Conclusions: This work establishes a robust manufacturing platform that overcomes stability challenges in alkalizer-containing formulations, facilitating the successful advancement of aneratrigine to Phase 2a and providing a model for developing heat- and moisture-sensitive compounds. Full article

Groundwater at petroleum-contaminated sites typically exhibits elevated dissolved inorganic carbon (DIC) levels due to hydrocarbon biodegradation; however, our prior field investigations revealed an enigmatic DIC depletion anomaly that starkly contradicts this global pattern and points to an unrecognized carbon sink. In a breakthrough demonstration, this study provides the first experimental confirmation that sulfur-oxidizing bacteria (SOB) drive substantial carbon sequestration via a coupled sulfur oxidation autotrophic assimilation process. Through integrated hydrochemical monitoring and 16S rRNA sequencing in an enrichment culture system, we captured the complete DIC transformation trajectory: heterotrophic acetate degradation initially increased DIC to 370 mg/L, but subsequent autotrophic assimilation by SOB dramatically reduced DIC to 270 mg/L, yielding a net consumption of 85 mg/L. The distinctive pH dynamics (initial alkalization followed by acidification) further corroborated microbial regulation of carbon cycling. Critically, Pseudomonas stutzeri and P. alcaliphila were identified as the dominant carbon-fixing agents. These findings definitively establish that chemolithoautotrophic SOB convert DIC into organic carbon through a “sulfur oxidation-carbon fixation” coupling mechanism, overturning the conventional paradigm of petroleum-contaminated sites as perpetual carbon sources. The study fundamentally redefines natural attenuation frameworks by introducing microbial carbon sink potential as an essential assessment metric for environmental sustainability. Full article

Electrochemical treatment by means of direct current (DC) is usually used as a measure for steel rebar corrosion protection, e.g., cathodic protection (CP), electrochemical chloride extraction (ECE), and re-alkalization (RA). However, the passage of an electrical charge through the pore system of concrete or mortar, coupled with the migration of ions, concentration changes, and resulting phase changes, may alter its chloride penetration resistance and, subsequently, the time until rebar corrosion activation. Porosity changes in hardened Portland cement mortar were studied by means of mercury intrusion porosimetry (MIP) and electrochemical impedance spectroscopy (EIS), and alterations in the mortar surface phase composition were observed by means of X-ray diffraction (XRD). In order to innovatively investigate the impact of DC treatment on the properties of the mortar–electrolyte interface, the cathode-facing mortar surface and the anode-facing mortar surface were analyzed separately. The corrosion of steel coupons embedded in DC-treated hardened mortar was monitored by means of the free corrosion potential (E_oc) and polarization resistance (R_p). The results showed that the DC treatment affected the surface porosity of the hardened Portland cement mortar at the nanoscale. Up to two-thirds of the small pores (0.001–0.01 µm) were replaced by medium-sized pores (0.01–0.06 µm), which may be significant for chloride ingress. Although the porosity and phase composition alterations were confirmed using other techniques (EIS and XRD), corrosion tests revealed that they did not significantly affect the time until the corrosion activation of the steel coupons in the mortar. Full article

Soil salinization severely limits global agricultural sustainability, particularly across the saline–alkaline landscapes of the Qinghai–Tibet Plateau. We examined how potassium fulvate (PF) modulates oat (Avena sativa L.) performance, soil chemistry, and rhizospheric microbiota in the saline–alkaline soils of the Qaidam Basin. PF markedly boosted shoot and root biomass, with the greatest response observed at 150 kg hm⁻². At the same time, it enhanced soil fertility by increasing organic matter, nitrate-N, ammonium-N, and available potassium, and improved ionic balance by lowering Na⁺ concentrations and the sodium adsorption ratio (SAR), while increasing Ca²⁺ levels and soil moisture content. Under the high-dose treatment (F2), endogenous fungal contributions declined sharply, exogenous replacements increased, and fungal α-diversity fell; multivariate ordinations confirmed that PF reshaped both bacterial and fungal communities, with fungi exhibiting the stronger response. We integrated three machine learning algorithms—least absolute shrinkage and selection operator (LASSO), Random Forest (RF), and eXtreme Gradient Boosting (XGBoost)—to minimize the bias inherent in any single method. We identified microbial β-diversity, organic matter, and Na⁺ and Ca²⁺ concentrations as the most robust predictors of the Soil Salinization and Alkalization Index (SSAI). Structural equation modeling further showed that PF mitigates salinity chiefly by improving soil physicochemical properties (path coefficient = −0.77; p < 0.001), with microbial assemblages acting as key intermediaries. These findings provide compelling theoretical and empirical support for deploying PF to rehabilitate saline–alkaline soils in alpine environments and offer practical guidance for sustainable land management in the Qaidam Basin. Full article

The paper presents a comprehensive study of the processing possibilities for phosphogypsum, a large-tonnage chemical industry waste, into highly sought-after products, such as ultraviolet pigments, and alkalizing reagents for the preparation of organomineral fertilizers. The materials obtained were characterized by X-ray diffraction (XRD), transmission electron microscopy, and thermogravimetric analysis (TGA). It was found that the phosphogypsum thermal treatment process in the presence of a reducing agent (charcoal, sunflower husk) allowed us to obtain new products with a high added value. For the first time, the possibility of obtaining various products by varying process conditions was established. The process of thermal reduction of phosphogypsum in the presence of charcoal at temperatures of 800–900 °C and an isothermal holding time of 60 min resulted in us obtaining samples capable of glowing when irradiated with ultraviolet light. This effect is due to the formation of a composite material based on calcium sulfide and calcium sulfate in the system. The process of the regenerative heat treatment of phosphogypsum at temperatures of 1000–1200 °C resulted in us obtaining a composite material consisting of calcium oxide and sulfate, which can be used for fractionating liquid waste from livestock farming and to obtain organomineral fertilizer. The technological methods developed allow the usage of chemical industrial waste and agricultural waste in secondary processing to produce highly innovative products that will contribute to the achievement of the sustainable development goals, in particular, “Ensuring rational consumption and production patterns”. Full article

Red mud, a highly alkaline industrial by-product generated during aluminum smelting, poses serious environmental risks such as soil alkalization and ecological degradation. In this study, response surface methodology (RSM) was integrated with advanced microstructural characterization techniques to optimize the performance of red mud–slag composite cementitious materials through multi-factor analysis. By constructing a four-factor interaction model—including red mud content, steel fiber content, alkali activator dosage, and calcination temperature—a systematic mix design and performance prediction framework was established, overcoming the limitations of traditional single-factor experimental approaches. The optimal ratio was determined via multi-factor RSM analysis as follows: the 28-day flexural strength and compressive strength of the specimens reached 12.26 MPa and 69.83 MPa, respectively. Furthermore, XRD and SEM-EDS analyses revealed the synergistic formation of C-S-H and C-A-S-H gels, and their strengthening effects at the fiber–matrix interfacial transition zone (ITZ), elucidating the micro-mechanism pathway of “gel densification–rack filling–strength enhancement.” This work not only enriches the theoretical foundation for the design of red mud-based binders but also offers practical insights and empirical evidence for their engineering applications, highlighting substantial potential in the development of sustainable building materials and high-value utilization of industrial solid waste. Full article

Due to prolonged irrigation from the Yellow River, a large area of farmland in the Hetao Oasis has undergone different degrees of salinization and alkalization, leading to reduced crop yields and incapable soil for plant growth. To enhance the productivity of the farmland with saline-alkali soils, it is important to select salt-tolerant economic plant species that are capable of growing under the local climate and soil conditions in the Hetao Oasis. We conducted the experiment by planting Ziziphus jujuba var. spinose, Elaeagnus angustifolia, Hippophae rhamnoides and Lycium chinense in the Bayan Taohai Farm of the Hetao Oasis. Changes of plant growth (the survival rate, plant height, canopy, basal diameter and new branch length) and soil physicochemical properties (soil organic carbon, total carbon, total nitrogen, pH, electrical conductivity and particle size distribution) were continuously monitored during two growing seasons. Results indicated that, by the end of the first growing season, the survival rate of the Z. jujuba was less than 10%, making it unsuitable for plantation in the saline-alkali soils of the Hetao Oasis. In terms of plant growth, the E. angustifolia exhibited the highest survival rate (94.71%) and the fastest growth rate, indicating that E. angustifolia is adapted in the saline-alkali soils of the Hetao Oasis. The survival rates for L. chinense and H. rhamnoides were 86.46% and 65.64%, respectively, indicating that these species could grow in the saline-alkali soils, but at a slower rate. From the perspective of soil improvement, E. angustifolia, H. rhamnoides and L. chinense could reduce the soil pH, and E. angustifolia could significantly increase soil nutrients. In conclusion, it is not recommended to plant Z. jujuba, while the E. angustifolia is recommended as a proper economic species to be widely planted in the saline-alkali soils of the Hetao Oasis. H. rhamnoides could be selectively planted in areas with better soil conditions, and the L. chinense could be planted following soil improvement measurements. The research enhanced the effective utilization of the saline-alkali farmland and provided proper economic plant species for sustainable agriculture management in the Hetao Oasis of Inner Mongolia. Full article

Soil salinization limits global agricultural sustainability, and extensive areas of saline–alkaline soils on the Qinghai–Tibet Plateau remain underutilized. Against this backdrop, this study evaluated the effects and ecological regulatory mechanisms of potassium fulvate (PF) application on oat (Avena sativa L.) growth, soil properties, and rhizosphere microbial communities in the saline–alkali soils of the Qaidam Basin. The results showed that PF significantly enhanced both aboveground and belowground biomass and improved root morphological traits, with the higher application rate (150 kg·hm⁻²) showing superior performance. PF also effectively improved soil nutrient conditions (organic matter, ammonium nitrogen, and potassium), reduced the integrated salinity–alkalinity index, significantly optimized the composition of rhizosphere soil cations (increased K⁺ and Ca²⁺; decreased Na⁺ and Mg²⁺), and induced a marked reshaping of the composition and structure of rhizosphere microbial communities. Notably, microbial β-diversity exhibited a significant regulatory effect on the comprehensive growth of oats. Structural equation modeling (SEM) revealed that PF primarily promoted oat growth indirectly by improving soil physicochemical properties (direct effect = 0.94), while the microbial community structure served as a synergistic ecological mediator. This study clarifies the regulatory mechanisms of PF in oat cultivation under alpine saline–alkali conditions, providing both theoretical and practical support for improving soil quality, enhancing forage productivity, and promoting sustainable agriculture in cold regions. Full article

The Quality by Design (QbD) concept has been widely applied to the optimization of traditional Chinese medicine production processes recently. This work focused on optimizing the critical purification process of Scutellaria baicalensis extract used in the preparation of Zhusheyong Shuanghuanglian. Considering the impact of noise parameters and changes in herbal properties, an experimental design method was employed for optimization. Multiple batches of Scutellaria baicalensis decoction were prepared in this research, and quantitative models of Scutellaria baicalensis herbal properties, critical process parameters (CPPs), and process evaluation indicators were established. The R² of the quantitative models were all higher than 0.80. According to the model, the yield of baicalin was identified as a critical material property (CMA). The pH of first acid precipitation (X₁), first temperature holding time (X₂), pH of alkalization (X₃), ethanol amount (X₄), and end pH of ethanol washing (X₅) were CPPs. Considering the difficulty in controlling the end pH of the ethanol washing, it was considered to be a noise parameter. The Monte Carlo probability-based method was used to calculate the design space, determining the range of controllable parameters, which was successfully validated through experiments. Normal operation ranges for controllable parameters are recommended as follows: X₁ of 0.8–2.2, X₂ of 25–35 min, X₃ of 6.5–7.5, and X₄ of 0.8–1.2 g/g. Full article

Soil salinization and alkalization are becoming increasingly severe in recent decades, which poses serious threats to crop production and food security in the world. Foxtail millet (Setaria italica L.) is an important cereal crop in China, and it is important to elucidate its saline-alkali tolerance mechanisms for the breeding of new saline-alkali tolerant varieties. In this study, we used 75% seawater to treat two foxtail millet varieties with different saline-alkali tolerances (JK3, saline-alkali tolerant; B175, saline-alkali sensitive) during the seedling stage, and conducted morphological, cellular ultrastructure, physiological, and transcriptomic analyses on the two varieties. The morphological analysis of the saline-alkali response indicated that JK3 exhibited stronger saline-alkali tolerance than B175. The results of the cellular ultrastructure showed that under saline-alkali stress, JK3 had a more intact leaf cell structure than B175, indicating that saline-alkali stress causes less damage to its cells. The physiological analysis of saline-alkali response indicated that JK3 had consistently higher activities of catalase and polyphenol oxidase, as well as higher contents of soluble sugars and soluble proteins at 48–120 h than B175. Transcriptomic analysis revealed that JK3 enhanced its saline-alkali tolerance by positively regulating pathways such as tryptophan/fatty acid metabolism, the MAPK signaling pathway, and peroxisome pathways. Further, WGCNA combining morphological and physiological indicators identified four key modules and five functional pathways (MAPK signaling, glycerolipid metabolism, phosphate and phosphonate metabolism, galactose metabolism, and endoplasmic reticulum protein processing) in response to saline-alkali stress, and identified a total of 24 core genes. Functional annotation indicated that these genes may be involved in the response to saline-alkali stress. These findings lay a foundation for in-depth studies of the molecular mechanisms for saline-alkali tolerance in foxtail millet. Full article

Biochar is increasingly being applied to improve various degraded soils. However, studies on its use in ameliorating saline–alkaline grasslands remain limited. This study conducted experimental trials using soil collected from an alkalized meadow grassland in the Horqin Steppe, applying biochar with the application rates of 0, 1.5, 3.0, and 4.5 kg/m² in planting boxes. The objectives were to evaluate the effects of biochar addition on soil properties and microbial community and to explore the feasibility of using biochar for alkalized grassland improvement. Biochar addition to alkalized meadow soil enhanced the biomass of planted Astragalus adsurgens and improved soil properties. Soil bulk density was reduced; porosity, moisture content, and field moisture capacity significantly increased; soil nutrients were significantly ameliorated. Simultaneously, soil enzyme activities, including urease, phosphomonoesterase, protease, and polyphenol oxidase, significantly increased. Biochar application altered the microbial community structures in the alkalized meadow soil, primarily through the shifts in the relative abundance of dominant taxa rather than the fundamental changes in dominant phyla or genera. Biochar addition significantly raised the abundance of phoD- and nifH-harboring microorganisms, suggesting the enhancement in functions of soil N fixation and P transformation. Key factors influencing bacterial community structure included electrical conductivity, total P, total K, bulk density, and available K, whereas fungal communities were primarily affected by bulk density, porosity, and available N. Excessive biochar application can diminish its yield-enhancing effects, and the recommended biochar application rate for alkalized meadow grasslands in practice is 1.5 kg/m². These findings are expected to provide experimental evidence for utilizing biochar in degraded grasslands improvement. Full article

Soil saline-alkalization is a key factor affecting rice growth and physiological metabolism, which leads to reduced yields. Endophyte EF0801 significantly promoted growth and improved its saline-alkali resistance. We investigated growth parameters and physiological indices of endophyte EF0801-infected and control rice seedlings under sodium carbonate (Na₂CO₃) stress. The results showed that endophyte-infected rice seedlings showed plant height increase by 1.25-fold, root length shortening by 0.79-fold, sucrose synthase (SS), sucrose phosphosynthase (SPS), hexokinase (HXK), and α-glucosidase (α-GC) activities increased by 0.15-fold, 0.29-fold, 0.06-fold, and 1.45-fold, respectively, and β-glucosidase (β-GC) activity decreased by 0.12-fold. Utilizing gas chromatography and mass spectrometry (GC-MS) technology and RNA sequencing (RNA-seq) technology, we identified 419 differentially expressed genes (DEGs) and 37 differentially accumulated metabolites (DAMs). Comprehensive enrichment analysis of DAMs and DEGs showed that 6 DEGs and 6 DAMs were strongly correlated with the mitigating effects of endophytes on rice leaves under Na₂CO₃ treatment, highlighting the co-enrichment in starch and sucrose metabolism, as well as alanine, aspartate, and glutamate metabolism. The gene encoding HXK was found to be upregulated in endophyte-infected rice seedlings under Na₂CO₃ stress. HXK plays a key role in the conversion of fructose and glucose to fructose 6-phosphate (F-6-P) and glucose 6-phosphate (G-6-P), which are important intermediates in cellular energy metabolism and glycolytic pathways, providing energy and biosynthesis of precursor substances. Our findings provide a potential perspective for unraveling the molecular response of endophyte-mediated saline-alkali resistance in rice leaves and a theoretical rationale for exploring the mechanisms of growth-promoting effects by endophytes. Full article

Dronedarone (DRO) is an antiarrhythmic drug that should be used under close supervision, and therapeutic drug monitoring (TDM) may be one of the tools supporting pharmacotherapy. The aim of our study was to develop an economical HPLC method for determining DRO and its active metabolite debutyldronedarone (DBD) in human plasma. An HPLC isocratic system with a manual injector was applied. The separation was performed on a Supelcosil LC-CN column (150 × 4.6 mm, 5 µm) at an ambient temperature. The mobile phase was a mixture of CH₃OH:CH₃CN:H₂O:0.5 M KH₂PO₄ (170:85:237.2:7.8 (v/v)) + 0.1 mL 85% H₃PO₄ pumped at a flow rate of 1.8 mL/min. The UV detection was set at λ = 290 nm. A methyl tert-butyl ether was used for the extraction from a 0.4 mL alkalized plasma sample. The analytes were eluted at retention times of 4.0 min, 5.2 min and 6.0 min for DBD, internal standard bepridil and DRO, respectively. The method was calibrated in the range of 10–1000 ng/mL for both DRO and DBD. The adequate specificity, accuracy and precision were demonstrated in accordance with EMA guidelines, i.e., ≤15% (≤20% for the LLOQ), which ensures the reliability of the measurements. This method can be recommended for laboratories with basic HPLC equipment for TDM, adherence assessments and even in PK studies during chronic DRO therapy. Full article