Binding Capacity Research Articles

BS O05 - Prevalence and Patterns of Iron Deficiency in Patients Living with Obesity: Insights from Bariatric Surgery Candidates

Abstract Background Iron deficiency anaemia (IDA) is a recognised complication of obesity, and its associated co-morbidities. Iron deficiency has been implicated in immunologic dysfunction in obesity. However, the patterns of iron deficiency in people with obesity, independent of IDA, and its implications for patients with obesity remain unclear. This study aimed to investigate potential causes of iron deficiency, including relationship with glycaemic control and relationship with systemic inflammation. Relationship between iron deficiency and body mass index (BMI) was also considered. Method A retrospective review of a prospectively maintained database of consecutive patients undergoing bariatric surgery was performed. Pre-operative haematologic assessments were reviewed, and linear regression models were used to identify the associations of iron deficiency in patients with obesity. Statistical analysis was performed using SPSS. 384 consecutive patients over a 2-year time period were included in the analysis. 72.1% of patients were female and the mean age was 49.44±10.2. The mean weight of included patients was 144.1±31.02 kg, and the mean BMI was 50.66±9.61 kg/m2 Results ​2.45% of patients met the criteria for iron deficiency anaemia. However, 15.49 % had low serum iron(<9 mmol/L), 12.1% had low ferritin(<30mg/L), 1.38% had low transferrin(<2g/L), 15.17% had high Total Iron Binding Capacity(>71.6mmol/L), 37.93% had low transferrin saturation(<20%). High BMI was a significant predictor of low serum iron(β=-0.206, p=0.031). Dysregulated glycaemic metabolism(HbA1c and glucose) was not a significant predictor of iron deficiency. Baseline inflammation (elevated CRP) was associated with low serum iron(β=-0.320, p=<0.001) and low transferrin(β=-0.205, p=0.028). Conclusion Iron deficiency in patients with obesity is common, but not iron deficiency anaemia dependent. It does not appear to be linked to patients’ glycaemic regulation, as previously thought. Our findings suggest it may instead be attributable to the systemic inflammation caused by obesity.

Phosphorylated Covalent Organic Framework Membranes Toward Ultrafast Single Lithium‐Ion Transport

AbstractDeveloping all‐solid‐state electrolytes, the chips for lithium‐metal batteries, with superior electrochemical and mechanical properties awaits the disruptive materials. Herein, ionic covalent organic framework membranes are explored as solid‐state electrolytes for single Li+ conduction. In the membrane, the anion groups act as Li+ transporter, determining Li+ binding capacity and releasing ability, whereas the oxygen‐containing groups act as Li+ co‐transporter, creating relay sites between adjacent Li+ transporters for rapid hopping. The membrane exhibits an unprecedented Li+ conductivity of 1.7 mS cm−1 with a Li+‐transference number close to unity at room temperature. Additionally, the membrane possesses high flexibility, low interfacial resistance, and excellent cycling performance at room temperature. This work paves an unprecedented path for the advancement of next‐generation Li+ conductors in solid‐state electrolytes.

The Effect of Hydrodynamic Cavitation on the Structural and Functional Properties of Soy Protein Isolate–Lignan/Stilbene Polyphenol Conjugates

In this study, hydrodynamic cavitation technology was utilized to prepare conjugates of soy protein isolate (SPI) with polyphenols, including resveratrol (RA) and polydatin (PD) from the stilbene category, as well as arctiin (AC) and magnolol (MN) from the lignan category. To investigate the effects of hydrodynamic cavitation treatment on the interactions between SPI and these polyphenols, the polyphenol binding capacity with SPI was measured and the changes in the exposed sulfhydryl and free amino contents were analyzed. Various methods, including ultraviolet–visible spectroscopy, fluorescence spectroscopy, Fourier transform infrared spectroscopy, and circular dichroism spectroscopy, were also used to characterize the structural properties of the SPI–polyphenol conjugates. The results showed that compared to untreated SPI, SPI treated with hydrodynamic cavitation exposed more active groups, facilitating a greater binding capacity with the polyphenols. After the hydrodynamic cavitation treatment, the ultraviolet–visible absorption of the SPI–polyphenol conjugates increased while the fluorescence intensity decreased. Additionally, the content of exposed sulfhydryl and free amino groups declined, and changes in the secondary structure were observed, characterized by an increase in the α-helix and random coil content accompanied by a decrease in the β-sheet and β-turn content. Furthermore, the SPI–polyphenol conjugates treated with hydrodynamic cavitation demonstrated improved emulsifying characteristics and antioxidant activity. As a result, hydrodynamic cavitation could be identified as an innovative technique for the preparation of protein–phenolic conjugates.

Surface Functionalized Plasmonic Sensors for Uric Acid Detection With Gold-Graphene Stacked Nanocomposites

Abstract This study presented a surface-functionalized sensor probe using 3-aminopropyltriethoxysilane (APTES) self-assembled monolayers on a Kretschmann-configured plasmonic platform. The probe featured stacked nanocomposites of gold (via sputtering) and graphene quantum dots (GQD, via spin-coating) for highly sensitive and accurate uric acid (UA) detection within the physiological ranges. Characterization encompassed the field emission scanning electron microscopy for detailed imaging, energy-dispersive X-ray spectroscopy for elemental analysis, and Fourier transform infrared spectroscopy for molecular identification. Surface functionalization increased sensor sensitivity by 60.64%, achieving 0.0221 °/(mg/dL) for the gold-GQD probe and 0.035 5 °/(mg/dL) for the gold-APTES-GQD probe, with linear correlation coefficients of 0.8249 and 0.8509, respectively. The highest sensitivity was 0.070 6 °/(mg/dL), with a linear correlation coefficient of 0.993 and a low limit of detection of 0.2 mg/dL. Furthermore, binding affinity increased dramatically, with the Langmuir constants of 14.29 µM−1 for the gold-GQD probe and 0.000 1 µM−1 for the gold-APTES-GQD probe, representing a 142 900-fold increase. The probe demonstrated notable reproducibility and repeatability with relative standard deviations of 0.166% and 0.013%, respectively, and exceptional temporal stability of 99.66%. These findings represented a transformative leap in plasmonic UA sensors, characterized by enhanced precision, reliability, sensitivity, and increased surface binding capacity, synergistically fostering unprecedented practicality.

The role of serum albumin in Candida albicans filamentation, germ tube formation, and farnesol sequestration

ABSTRACT Candida albicans is an opportunistic pathogen and colonizer of the human gut and mucosal membranes. C. albicans exhibits morphological plasticity, which is crucial for its fitness within the host and virulence. Morphogenesis in C. albicans is regulated, in part, by its production of farnesol, an autoregulatory molecule that inhibits filamentation. Morphogenesis is also regulated in response to external cues, such as serum, which stimulates hyphal formation by C. albicans . The precise mechanism by which serum stimulates hyphal formation is unknown. The most abundant serum protein is albumin. The binding affinity of albumin for nonpolar, fatty-acid-like molecules suggests that it may interact directly with exogenous farnesol and influence morphogenesis through sequestration of free farnesol. To test this hypothesis, we assessed whether albumin and albumin devoid of fatty acids (i) stimulated farnesol secretion and (ii) influenced the farnesol threshold required to inhibit filamentation. We found that albumin promoted farnesol secretion and filamentation, and the extent of its ability to do so was based on the presence or absence of bound fatty acids. We hypothesize that albumin not bound to fatty acids has the capacity to bind to farnesol and sequester it from C. albicans , encouraging filamentation. IMPORTANCE For at least 50 years, researchers have wondered about the mechanisms by which serum stimulates germ tube formation (GTF) and hyphal growth in C. albicans . Here, we tested a model (Nickerson et al., Microbiol Mol Biol Rev 88:e00081-22, 2024, https://doi.org/10.1128/mmbr.00081-22 ) that serum promotes GTF and farnesol synthesis in part by extracting internal farnesol (F i ) from the cells toward the excess binding capacity of the albumins. The data presented here suggests that albumin not bound by fatty acids sequesters free farnesol thereby modulating filamentation and farnesol secretion by altering the equilibrium of internal vs external farnesol. We expect that the influence of secreted farnesol on cell morphology will differ during pathogenesis depending on location within the body, but sequestration of farnesol in the blood could mediate immune cell recruitment and promote hyphal formation.

Evaluation of Mixing Temperature in the Preparation of Plant-Based Bigels

Understanding gel structures and behavior is a prerequisite for attaining the desired food application characteristics. The mixing temperature is crucial when incorporating thermolabile active compounds into gels. This study evaluated the effect of mixing temperature on the physical and chemical properties of a bigel system prepared using a carnauba wax/canola oil oleogel and Arabic gum hydrogels. The results showed that bigels prepared at lower temperatures (30 and 40 °C) resulted in a solid-like state under crystallization temperature, resulting in matrices with larger hydrogel droplets, softer texture, and lower adhesiveness, spreadability, and solvent binding capacity. In contrast, bigels prepared at higher temperatures (50 and 60 °C), around crystallization temperature but with no solid state, resulted in matrices with smaller hydrogel droplets and higher firmness, adhesiveness, and spreadability. These bigels had a higher apparent viscosity, especially at lower shear rates, and solid-like behavior in the linear viscosity range. During the bigel preparation process, adjusting the mixture temperature had no effect on the samples’ oxidative stability, FTIR spectra, or thermal properties. The results highlighted the importance of hydrogel droplet size on the microstructure of the formed bigels, and smaller droplets could act as effective fillers to reinforce the matrix without making chemical changes.

Network pharmacology and molecular docking to explore the potential molecular mechanism of chlorogenic acid treatment of oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is a tumor type with a high mortality rate. Chlorogenic acid, abundant in resources and widely utilized in cancer treatments, has seen limited studies regarding its efficacy against OSCC. This paper investigates chlorogenic acid’s mechanism in treating OSCC, aiming to guide the development of novel drugs. The study employed network pharmacology, molecular docking, and survival analysis methods. Network pharmacological analysis revealed chlorogenic acid targets 23 OSCC-related proteins, including ESR1, MMP2, MMP9, SRC, MAPK8, MAPK1, CDC42, ERBB2, ATM, and BRAF. Molecular docking simulations indicated that the primary target exhibits significant binding capacity with chlorogenic acid, with MMP9 associated with tumor migration and angiogenesis standing out. Survival analysis demonstrated that the downregulation of most primary targets correlates with improved survival rates in OSCC patients. Enrichment analysis of therapeutic targets highlighted the pivotal role of MAPK-ERK and MAPK-JNK signaling pathways in chlorogenic acid’s efficacy against OSCC. This paper predicts chlorogenic acid’s potential targets and proposes its molecular mechanism in treating OSCC, offering a theoretical foundation for its application in OSCC treatment. We used traditional Chinese medicine, a disease pharmacology-related information base, and an analysis platform to predict targets. The Cytoscape 3.9.1 and STING databases were used to address common targets for drugs and diseases, establish networks of protein interaction relationships, and screen core targets. Meastro11.5 was used for molecular docking simulation. R4.2.2 was used for survival analysis and joint target enrichment analysis. Network pharmacological analysis identified chlorogenic acid acting on 23 OSCC targets. Molecular docking simulations revealed a strong binding affinity of chlorogenic acid compounds with these targets, particularly MMP9, essential for tumor migration and angiogenesis. Survival analysis indicated that the downregulation of most core targets was correlated with improved OSCC patient survival. Enrichment analysis of therapeutic targets highlighted the critical roles of the MAPK-ERK and MAPK-JNK signaling pathways in the effectiveness of chlorogenic acid against OSCC. This study predicted the potential targets of chlorogenic acid in OSCC treatment and hypothesized its molecular mechanism, offering a theoretical foundation for its use in OSCC therapy.

Physicochemical Properties and Metal Ion-Binding Capacity of Thermal-Induced Antarctic Krill Protein Aggregates under Different pH Conditions.

Protein properties can be modified by thermal treatment at different pH values, resulting in the formation of protein aggregates with diverse morphologies and functionalities. This study investigated the morphology of aggregates of Antarctic krill protein (AKPS) formed by thermal treatment (90 °C, 15 min) at pH 2, 3, 4, and 6-12, characterized the different morphologies of AKPS, and determined the metal ion (Ca2+, Fe2+, and Zn2+)-binding capacities. Results showed that heat treatment with different pH values generated various AKPS with distinct morphology and metal ion-binding abilities. AKPS have formed fibrils at pH ≤ 3, particles at pH 4-7, and amorphous aggregates at pH ≥ 8. Fibrous AKPS (pH 2) exhibited a high solubility (80.36%) and strong reducing effect on iron. The binding capacities of Ca2+ and Fe2+ reached 36.08% and 66.75%. Particulate AKPS (pH 6 and 7) primarily only showed Zn2+-binding capacity similar to that of casein phosphopeptide (17.33%). Amorphous AKPS (pH 9-11) displayed the optimal capacity to bind Zn2+ and Fe2+ (26.90% and 74.94%). The alterations in morphology and functional characteristics of AKPS permit the design of various nanostructures for food-derived mineral supplements, thus developing their potential for application in functional foods.

Association of Clinical and Paraclinical Factors with Pain Crisis Severity in Sickle-Thalassemia Patients in Iran

Objectives: This study aimed to evaluate the effects of several factors, including hospitalization frequency, inflammatory and hemolytic markers, and the numbers of blood transfusions and crises, on the severity of pain crises in sickle-thalassemia patients. Methods: Of all patients visiting hematologists in university-affiliated hospitals and clinics, only 75 sickle cell disease (SCD) and sickle-thalassemia patients met the inclusion criteria for this study. Disease severity was measured based on pain crises per year and laboratory markers, including hemolytic and inflammatory indicators, outpatient or inpatient status, the number of hospital admissions, and the number of blood units transfused over one year. Results: In sickle cell patients, a significant correlation was observed between hospital admission and WBC (0.01), ALP (0.001), MCHC (0.001), ferritin (0.021), and ESR (0.006). Additionally, pain crises were positively correlated with transferrin saturation (TS) (+0.28) and the number of transfused blood units (+0.49) and negatively correlated with Hb (-0.30) and total iron binding capacity (TIBC) (-0.23). Blood unit transfusions showed a positive correlation with serum iron (+0.44), RDW (+0.36), ferritin (+0.39), pain crises (+0.49), and TS (+0.49), along with a negative correlation with Hb (-0.75) and MCHC (-0.33). When categorizing pain crises into two groups, patients experiencing more frequent crises generally exhibited lower hemoglobin levels and a higher number of blood units transfused. Hemoglobin also showed a significant negative correlation with lactate dehydrogenase (LDH) level in both groups: -0.604 (P = 0.005) in patients with ≥ 3 crises per year and -0.368 (P = 0.006) in patients with < 3 crises per year. Patients with hemoglobin levels of 7.5 or higher tended to maintain an LDH level below 1000. Among patients referred with pain crises, hemoglobin was negatively correlated with hemolytic markers such as LDH (-0.41) and retic (-0.29). Conclusions: Hemoglobin and LDH can serve as follow-up markers, as they are routinely measured in all sickle cell patients and, in this study, hemoglobin levels of 7.5 or higher and LDH levels below 1000 were associated with fewer and less severe pain crises. Regular monitoring of hemolytic markers may help in pain crisis prevention, as this study found that hemolytic crises frequently coincided with pain crises. Further research is needed to provide conclusive evidence in this area.

A Natural Carbon Encapsulated in Gellan-Based Hydrogel Particles Designed for Environmental Challenges

This article reports the obtention of a new gellan-based hydrogel linked with Fe3+ and loaded with a natural micro/nanostructured carbon designed as a contaminant’s removal from wastewater. Hydrogels are known for their water-retaining properties, high binding capacity, and eco-friendly features. The new material is expected to behave as one cost-effective and efficient sorbent, including natural carbon structures with various functional groups. The encapsulation efficiency ranges between 89% and 95%. The obtained hydrogel particles were characterized using FT-IR spectroscopy and scanning electron microscopy techniques. The hydrogel particles’ water stability was evaluated by measuring the transmittance for 10 days, and the capacity to retain water was assessed by determining the swelling degree (Q%). The results showed that hydrogel particles are stable (the transmittance value is higher than 97.8% after 10 days), and their properties are influenced by the cross-linking degree, the amount of the carbon particles encapsulated, and the concentration of gellan. For example, the Q% values and encapsulation efficiency increased when the cross-linking degree, the carbon microstructure quantity, and the gellan concentration decreased. The new hybrid material can retain Pb(II) ions and diclofenac molecules, and could be used in different adsorption–desorption cycles.

Dissecting the role of the HA1-226 leucine residue in the fitness and airborne transmission of an A(H9N2) avian influenza virus.

Although the capacity for human-like receptor binding is a key prerequisite for non-human origin influenza A virus (IAV) to become airborne transmissible in mammalian hosts, the underlying molecular basis is not well understood. In this study, we investigated a naturally occurring substitution (leucine to glutamine) at residue 226 in the HA of an avian-origin A(H9N2) virus and assessed the impact on virus replication and airborne transmission in the ferret model. We demonstrate that the enhanced airborne transmission associated with the HA1-L226 virus was mainly due to the increased infectivity of the virus. Interestingly, we found that, unlike most sites in the ferret respiratory tract, ferret ethmoid turbinate lined with olfactory epithelium favors replication of the AL/39-HA1-L226Q virus, suggesting that this site may serve as a unique niche for IAV with avian-like receptor binding specificity to potentially allow the virus to spread to extrapulmonary tissues and to facilitate adaptation of the virus to human hosts.

Preclinical characterization of MTX-101: a novel bispecific CD8 Treg modulator that restores CD8 Treg functions to suppress pathogenic T cells in autoimmune diseases

IntroductionRegulatory CD8 T cells (CD8 Treg) are responsible for the selective killing of self-reactive and pathogenic CD4 T cells. In autoimmune disease, CD8 Treg may accumulate in the peripheral blood but fail to control the expansion of pathogenic CD4 T cells that subsequently cause tissue destruction. This CD8 Treg dysfunction is due in part to the expression of inhibitory killer immunoglobulin-like receptors (KIR; KIR2DL isoforms [KIR2DL1, KIR2DL2, and KIR2DL3]); these molecules serve as autoimmune checkpoints and limit CD8 Treg activation.MethodsHere we describe the pre-clinical characterization of MTX-101, a bispecific antibody targeting inhibitory KIR and CD8. Using human peripheral blood mononuculear cells (PBMC) derived from healthy donors and autoimmune patients, humanized mouse models, and human derived tissue organoids, we evaluated the molecular mechanisms and functional effects of MTX-101.ResultsBy binding to KIR, MTX-101 inhibited KIR signaling that can restore CD8 Treg ability to eliminate pathogenic CD4 T cells. MTX-101 bound and activated CD8 Treg in human peripheral blood mononuclear cells (PBMC), resulting in increased CD8 Treg cytolytic capacity, activation, and prevalence. Enhancing CD8 Treg function with MTX-101 reduced pathogenic CD4 T cell expansion and inflammation, without increasing pro-inflammatory cytokines or activating immune cells that express either target alone. MTX-101 reduced antigen induced epithelial cell death in disease affected tissues, including in tissue biopsies from individuals with autoimmune disease (i.e., celiac disease, Crohn’s disease). The effects of MTX-101 were specific to autoreactive CD4 T cells and did not suppress responses to viral and bacterial antigens. In a human PBMC engrafted Graft versus Host Disease (GvHD) mouse model of acute inflammation, MTX-101 bound CD8 Treg and delayed onset of disease. MTX-101 induced dose dependent binding, increased prevalence and cytolytic capacity of CD8 Treg, as well as increased CD4 T cell death. MTX-101 selectively bound CD8 Treg without unwanted immune cell activation or increase of pro-inflammatory serum cytokines and exhibited an antibody-like half-life in pharmacokinetic and exploratory tolerability studies performed using IL-15 transgenic humanized mice with engrafted human lymphocytes, including CD8 Treg at physiologic ratios.ConclusionCollectively, these data support the development of MTX-101 for the treatment of autoimmune diseases.

Rapid Screening of Active Components with Thrombin Inhibitory Activity from Peach Kernel Based on Affinity Ultrafiltration coupled with UPLC-Q-TOF-MS.

Peach kernel (PK), one of the medicinal and edible plants, has been widely used in the treatment of clinical thrombotic diseases and exhibited great therapeutic effects. However, the effective substances and targets are still obscure. A method consisting of affinity ultrafiltration (AUF) coupled with ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectroscopy (UPLC-Q-TOF-MS) was established to rapidly screen active components that inhibit thrombin, a key mediator in coagulation cascade. The binding energy and sites were analyzed by molecular docking to evaluate the binding capacity of thrombin-ligand complexes, and the thrombin inhibitory activity of screened ligands was further validated via in vitro and in vivo tests. two potential thrombin ligands (L-arginine and cytidine) were screened by AUF-HPLC and identified by UPLC-Q-TOF-MS. The ligands with anti-thrombin structure exhibited great affinity with thrombin. The anticoagulant bioactivity of ligands was validated by a significant reduction in thrombosis in zebrafish tails and the potential mechanism could be related to direct inhibition of thrombin. The systematic screening of anti-thrombin active components in PK based on AUF-UPLC-Q-TOF-MS is a feasible and effective method, providing valuable information for the future development of direct thrombin inhibitors.

Structural and functional properties of proteins isolated from four species of microalgae and their application in air-water interface stabilization

Herein, we extracted proteins from four microalgae: Chlamydomonas reinhardtii (CHR), Euglena gracilis (EUG), Spirulina platensis (SPP), and Spirulina maxima (SPM). Subsequently, their physicochemical and functional properties, as well as air-water interface adsorption behavior were investigated. Results demonstrated that the solubility and emulsifying properties of these proteins were significantly affected by pH, with minimum values observed near their isoelectric point (3.5) and maximum values at pH 11.0. Interestingly, the emulsifying properties of the four proteins were superior to soy protein isolate in the pH range of 3.0–7.0, indicating that these microalgae proteins may be suitable for applying as emulsifiers in foods. EUG exhibited the highest water/oil binding capacity, emulsifying activity, and emulsifying stability, which were attributed to its high surface hydrophobicity and β-sheet content, as well as small particle size. Dynamic adsorption behavior analysis illustrated that EUG showed faster diffusion and rearrangement rates, as well as a higher final equilibrated surface pressure value, contributing to its highest foaming capacity and foaming stability. This study greatly enhances the understanding of microalgae proteins and is expected to establish a theoretical foundation for developing novel protein resources that can be utilized in the foamed and emulsion-based food fabrication, including whipped cream and functional beverages.

The negative electrostatic potential of the coordination between calcium and carboxyl/oxygen group in calcium-peptide complexes contributes to calcium utilization

The coordination electrostatic potential has significantly influenced the binding energy of calcium-peptide coordination complexes. However, its impact on calcium bioavailability is unclear. A calcium-binding peptide (CBP) DEDEQIPSHPPR, purified from soybean yogurt was selected. The study selected tetrapeptide residues of acidic amino acids that play an important role in CBP and designed sixteen tetrapeptides rich in carboxyl oxygen atoms to investigate the influence of electrostatic potential on calcium-peptide binding. The results indicated that DEDE exhibited the strongest binding energy (−375.27 kcal/mol) and binding capacity (464.11 ± 2.14 mg/g) with calcium ions compared to other peptides. Moreover, DEDE also increased intracellular calcium concentration the most, being 2.04 times higher than CaCl2. Calcium ions coordinated with carboxyl oxygen atoms possessing negative electrostatic potential, which correlated positively with the bioavailability of calcium ions. This electrostatic potential analysis provides a theoretical basis for developing and screening bioactive peptides with high calcium bioavailability.

Experiment and simulation on the coupled effects of calcium leaching and chloride transport in concrete under hydraulic pressure

This study investigated the coupled effect of calcium leaching and chloride erosion on concrete subjected to hydraulic pressure by combining experiments and numerical simulations. Several tests including titration, pH, XRD, TG, MIP, and SEM-EDS were employed to analyze chloride concentration, pH value, solid phase compositions, and microstructure of concrete under hydraulic pressure. Concurrently, a model based on the physicochemical interactions between the pore solution and the hydration products was constructed to elucidate the process of calcium leaching and multi-ion transport. The experimental and simulation results reveal that hydraulic pressure accelerates calcium leaching in concrete, leading to a maximum porosity that reaches 1.5 times the initial porosity after a year. In addition, both the pH value and chloride binding capacity in the zone close to the exposure surface decrease. The enrichment of Ca2+ and OH− occurs at a specific depth within concrete during the calcium leaching process, and over time, this enrichment effect grows increasingly significant. Along the depth within the concrete, a transient increase in chloride binding capacity can be observed, which can be attributed to OH− and Ca2+ enrichment.

The coupling effect of calcined layered double hydroxides and impressed current cathodic protection system on chloride ion binding and migration of sea sand mortar

Chloride introduced by sea sand and sea water leads to steel bar corrosion. Calcined Layered double hydroxides (CLDH) and impressed current cathodic protection (ICCP) system were used to adsorb chloride ion and control steel bar corrosion in chloride abundant environment. In this research, chloride binding effect of two kinds of CLDH were investigated in simulated concrete pore solution. Besides, chloride absorption capacity and steel bar corrosion resistance of Mg-Al CLDH was explored in mortar. Further, hydration degree of mortar installed ICCP system and migration of ions around the anode and cathode were detected. Results show that Mg-Al CLDH exhibits excellent chloride binding capacity and corrosion resistance. After installing the ICCP system, corrosion of steel bars in mortar mixed Mg-Al CLDH was controlled. And ions in mortar specimen around anode or cathode exhibits migration phenomenon in different degree. A two stage-four step model was established to explain the degradation of hydration products and ion migration in CLDH-ICCP system. Under the ICCP system, Cl− in pore solution increased at early stage and then decreased both around anode and cathode, the increment process was controlled by desorption of Mg-Al CLDH and decreased process was controlled by degradation of hydration products. Therefore, the CLDH-ICCP system was recommended to solve the problem of steel bar corrosion introduced by marine environment.

Effect of reduced flaxseed cyclic peptide [1–9-NαC]-linusorb B2 (CLB) and its oxidized form on the oxidative stability of flaxseed oil

This study aimed to explore the antioxidant capacity and mechanism of cyclic peptide [1–9-NαC]-linusorb B2 (CLB) and its oxidized form ([1–9-NαC],[1-MetO]-linusorb B2 (CLC),[1–9-NαC],[1-MetO2]-linusorb B2 (CLK)) in flaxseed oil (FSO). The results showed that CLB delayed the oxidation of FSO (containing Cu2+) in the initial stage of accelerated oxidation, whereas CLK accelerated the oxidation, leading to an increase of 25 % in AV and 33 % in POV (P < 0.05). In molecular docking, the binding ability of cyclic peptides to metal ions and intermediate oxidative products such as aldehydes tends to decrease when CLB oxidized to CLC, then CLK. CLK had the poorest binding capacity with the most serious oxidation on FSO. In conclusion, the antioxidant capacities of CLB and its oxidized form were contributed by their reducing ability as well as their binding ability to metal ions and intermediate oxidative products of fatty acids.

Chitosan nanoparticles alleviate chromium toxicity by modulating metabolic homeostasis and promoting chromium sequestration in Zea mays L.

Chitosan nanoparticles (CSNPs) have been proposed as a potential alternative in alleviating chromium (Cr) toxicity. However, the mechanisms underlying remains poorly understood. This study investigates the effects of CSNPs on carbon/nitrogen metabolism, cell wall Cr binding capacity, and antioxidant activity in Zea mays L. under Cr stress. Cr stress decreased the total dry weight (DW) by 48.5 %. By contrast, the total DW was reduced by only 26.2 % in CSNPs-treated plants. Analysis of transcriptomic, enzyme activity, and metabolite content data, CSNPs-treated plants exhibited a higher level of relatively stable Carbon and Nitrogen metabolism than untreated plants. CSNPs application resulted in a substantial increase in the levels of sucrose and soluble protein by 78.0 % and 19.4 % in the leaves, and 60.0 % and 59.7 % in the roots, respectively. Meanwhile, CSNPs increased the contents of glutathione, phytochelatin, and cell wall polysaccharide. This increase resulted in a higher retention of Cr in vacuole and cell wall. Additionally, CSNPs alleviated the oxidative damage by improving antioxidant activity. Overall, our results suggest that CSNPs alleviates Cr toxicity by modulating metabolic homeostasis and promoting Cr sequestration in maize plants. This study provides new insights into the mechanisms underlying CSNPs-mediated Cr stress response with potential implications for crop production.

Utilization of soybean protein isolate hydrolysates as carriers: Improved encapsulation efficiency and stability of curcumin

This study aimed to explore the potential of soybean protein isolate hydrolysates (SPIH) prepared via Alcalase as delivery carriers and develop novel SPIH-Cur nanoparticles. Hydrolysis caused the varying degrees degradation in the 7S and 11S subunits, significantly enhancing SPI's antioxidant activity. The reduction in particle size and the exposure of hydrophobic groups in SPIH contributed to the formation of stable SPIH-Cur nanoparticles, due to their well binding capacity to curcumin (Cur). The 30 min SPIH-Cur sample exhibited the highest encapsulation efficiency (83.09 %), owing to its high binding affinity (Ka = 9.56 × 103 M−1). Encapsulation by SPIH also significantly improved Cur's thermal and light stability. Moreover, FTIR, fluorescence spectra, and molecular docking analyses revealed that the formation of SPIH-Cur were primarily driven by hydrophobic forces and hydrogen bonds. Above results provide a foundation for fabricating nanoparticles that deliver lipophilic bioactive compounds with high encapsulation efficiency and stability derived from SPIH.