Citric Acid Research Articles

Environmental pH and compound structure affect the activity of short-chain carboxylic acids against planktonic growth, biofilm formation, and eradication of the food pathogen Salmonella enterica.

Short-chain carboxylic acids (SCCAs) that are naturally produced by microbial fermentation play an essential role in delaying microbial spoilage. SCCAs are structurally diverse, but only a few of them are routinely used in food biopreservation. This study investigated the effects of environmental pH and intrinsic properties of 21 structurally different SCCAs on the antimicrobial and antibiofilm activity against Salmonella enterica. Inhibition of SCCA toward planktonic and biofilm growth of S. enterica was higher in an acidic environment (pH 4.5) that is common in fermented products, and for SCCA that possessed both a high acid dissociation strength (pKa) (>4.0) and a positive hydrophobicity [octanol/water partition coefficient (log Kow)]. Crotonic and caproic acids were identified as SCCAs with potential as biopreservatives even at near-neutral pH. SCCA with hydrophilic groups such as lactic acid did not inhibit S. enterica at concentrations up to 50 mM, while SCCA with benzene or methyl groups or a double bond prevented S. enterica growth and biofilm formation. Stimulation of biofilm formation was observed for formic, acetic, and propionic acid close to the minimum inhibitory concentration to reduce 50% of cell density (MIC50) of planktonic cells, and for citric and isocitric acid with an MIC50 of ≥50 mM. The presence of low concentrations of formic and propionic acids during biofilm formation conferred protection during eradication possibly due to a pre-adaptation effect, yet two consecutive acid treatments were successful in eradicating biofilms if the first acid treatment was two- to threefold of the MIC50.IMPORTANCEThis study provides a systematic comparison on the antimicrobial and antibiofilm activity of more than 20 structurally different SCCAs against a common food pathogen. We tested the antimicrobial activity at controlled pH and identified the structure-dependent antimicrobial effects of SCCA without the confounding influence of acidification. The combined effect of pKa and log Kow was identified as an important feature that should be considered when deciding for a specific SCCA in the application as antimicrobial. Our results imply that additional phenomena such as the use of SCCA as substrate and cellular pre-adaption effects have to be taken into consideration. We finally present a two-step treatment as an efficient approach to eradicate biofilms, which can be applied for the disinfection of contact surfaces and manufacturing equipment. Results obtained here can serve as guidelines for application of SCCA to avoid the growth of food pathogens and/or to develop biopreserved food systems.

New Insights into Mitochondria in Health and Diseases

Mitochondria are a unique type of semi-autonomous organelle within the cell that carry out essential functions crucial for the cell’s survival and well-being. They are the location where eukaryotic cells carry out energy metabolism. Aside from producing the majority of ATP through oxidative phosphorylation, which provides essential energy for cellular functions, mitochondria also participate in other metabolic processes within the cell, such as the electron transport chain, citric acid cycle, and β-oxidation of fatty acids. Furthermore, mitochondria regulate the production and elimination of ROS, the synthesis of nucleotides and amino acids, the balance of calcium ions, and the process of cell death. Therefore, it is widely accepted that mitochondrial dysfunction is a factor that causes or contributes to the development and advancement of various diseases. These include common systemic diseases, such as aging, diabetes, Parkinson’s disease, and cancer, as well as rare metabolic disorders, like Kearns–Sayre syndrome, Leigh disease, and mitochondrial myopathy. This overview outlines the various mechanisms by which mitochondria are involved in numerous illnesses and cellular physiological activities. Additionally, it provides new discoveries regarding the involvement of mitochondria in both disorders and the maintenance of good health.

Cisplatin-Induced Metabolic Responses Measured with Raman Spectroscopy in Cancer Cells, Spheroids, and Canine-Derived Organoids.

Ex vivo assessment of drug response with conventional cell viability assays remains the standard practice for guiding initial therapeutic choices. However, such ensemble approaches fail to capture heterogeneities in treatment response and cannot identify early markers of response. Here, we leverage Raman spectroscopy (RS) as an accurate, low-cost, extraction-free, and label-free approach to track metabolic changes in cancer cells, spheroids, and organoids in response to cisplatin treatment. We identified 12 statistically significant metabolites in cells and 19 metabolites in spheroids and organoids as a function of depth. We show that the cisplatin treatment of 4T1 cells and spheroids results in a shift in metabolite levels; metabolites including nucleic acids such as DNA, 783 cm-1 with p = 0.00021 for cells; p = 0.02173 for spheroids, major amino acids such as threonine, 1338 cm-1 with p = 0.00045 for cells; p = 0.01022 for spheroids, proteins such as amide III, 1248 cm-1 with p = 0.00606 for cells; p = 0.00511 for spheroids serve as early predictors of response. Our RS findings were also applicable to canine-derived organoids, showing spatial variations in metabolic changes as a function of organoid depth in response to cisplatin. Further, the metabolic pathways such as tricarboxylic acid (TCA)/citric acid cycle and glyoxylate and dicarboxylate metabolism that drive drug response showed significant differences based on organoid depth, replicating the heterogeneous treatment response seen in solid tumors where there is a difference from the periphery to the tumor core. Our study showcases the versatility of RS as a predictive tool for treatment response applicable from cells to organotypic cultures, that has the potential to decrease animal burden and readout time for preclinical drug efficacy.

Formulation and Evaluation of Gastroretentive Bilayer Tablets

Gastroretentive bilayer tablets were designed to prolong the gastric residence time after oral administration and to achieve immediate release of lansoprazole and controlled release floating layer of clarithromycin to treat gastric ulcers. Instant release layer has a combination of super disintegrating agents. A combination of effervescent mechanism is used. HPMC K5 was used as swelling polymer and citric acid, sodium bicarbonate as gas generating agent to reduce the floating lag time. Bilayer floating tablets were prepared with varying proportions of instant layer and sustained release floating approaches. The prepared formulations were evaluated for various tablet and floating parameters. Tablet properties were found to be within the limits according to procedures prescribed in USP. They had a floating lag time around 3-7 seconds and floating time more than 24 hours. The cumulative % drug release in simulated gastric fluids after 10 hours was 70% - 95%. The mechanism of drug release was analyzed by fitting the release data into various kinetic models. It was found that all the formulations best fit the Higuchi’s model. Keywords: Gastroretentive drug delivery system; Bilayer tables, Instant release layer, Floating layer, Lansoprazole, Clarithromycin.

Role of citric acid in selective flotation of limonite from quartz using sodium oleate as collector

The issue that eliminating the negative effects of inevitable ions in the pulp on mineral flotation separation has attracted widespread attention. To achieve the efficient flotation separation of limonite from quartz, citric acid was utilized as a depressant for quartz in this paper. The solubility of limonite was studied using inductively coupled plasma tests (ICP), and the effect of Fe3+ and citric acid on the separation of limonite from quartz under sodium oleate (NaOL) system was investigated using batch flotation tests. The underlying mechanisms were probed through zeta potential measurements, infrared spectroscopy (IR), X-ray photoelectron spectroscopy (XPS), and contact angle detection. It was found that limonite could dissolve a certain number of Fe3+ in the pulp. These Fe3+ adsorbed onto quartz and acted as the active sites to promote the adsorption of NaOL, thereby enhancing quartz flotation evidently and deteriorating the separation of limonite from quartz. Fortunately, citric acid could depress the flotation of iron-activated quartz quite well by covering and desorbing the active sites of Fe3+ and causing the steric hindrance to prohibit the adsorption of NaOL. Meanwhile, the hydrophilic groups in citric acid could also increase the surface hydrophilicity of quartz and enhance the inhibitory effect. In comparison, Fe3+ and citric acid had little effect on the adsorption of NaOL onto limonite since its surface exposed enough Fe-active sites for the adsorption of NaOL. Thus, the difference in the floatability of limonite and quartz was enlarged, eventually achieving a better separation of them. This research sheds new light on the role of citric acid in the selective separation of quartz from soluble iron minerals.

Development of a process for extracting rare earth elements from phosphogypsum by dissolving them in deep-eutectic solvent

ABSTRACT The exploitation of deep-eutectic solvents (DESs) offered a potential substitute for water-based solutions when it came to leaching REEs from phosphogypsum (PG). The REEs leachate from PG obtained by DES which comprised choline chloride (ChCl) and diglycolic acid (DGA) or lactic acid (LA). The data offered a successful method for REEs leaching by DES ChCl:LA. The optimal leaching conditions included 150 min, 70°C, ChCl:LA 1:2 molar ratio of 800 rpm, a 15:1 L/S ratio, and 15% additional water. Cyanex 923 was used to assess REEs extraction from DES leachate. The best parameters were 900 rpm, 0.8 M Cyanex/toluene at 25°C, with 15 min extraction time and 1/1 A/O ratio. The REEs were stripped from the REEs/Cyanex after equilibrating for 20 minutes using 0.7 M citric acid, 1/2 A/O ratio, and 1000 rpm at 25°C. The RE ions precipitated from the obtained stripping solution by 30% oxalic acid and pH 1. The RE oxalate was precipitated and then burned at 700°C to gain RE oxide. The RE oxide powder was subjected to analysis to determine the REEs; it was possible to determine that the REEs were 80.98% in RE oxide concentrate, resulting in a purity of 94.76%.

Field evaluation of symbiont-targeted control of Halyomorpha halys in hazelnut crop

Halyomorpha halys has emerged as one of the most damaging pests for hazelnut production. Due to the continuous reduction of available options for chemical control, alternative strategies are required. A promising and sustainable alternative is the use of symbiont-targeted control. Treatment of the egg surface with a biocomplex containing copper, zinc, and citric acid has been shown to effectively prevent the acquisition of the endosymbiont ‘Candidatus Pantoea carbekii’ by H. halys nymphs, resulting in high nymph mortality under laboratory conditions. The aim of this work was to assess the field efficacy of treatments targeting the H. halys symbiont in hazelnut orchards to optimize spray applications. Treatments with the anti-symbiont biocomplex were performed in an orchard infested with H. halys during 2022 and 2023. To assess product efficacy, H. halys egg masses were glued on cardboard tags and hung on different positions of plants canopy before the treatments. The wetting percentage of egg masses according to the position of the egg on the plant canopy was measured; eggs were then reared to evaluate nymphal mortality after hatching. Symbiont acquisition was measured by quantitative PCR. A preliminary test to set the spraying conditions revealed that a higher fan speed induced higher mortality of the newborns from treated egg masses, although it did not affect the wetting rate of cardboards. In addition, cardboard tags hung in the central part of the canopy and those closer to the sprayer showed the highest egg coverage, whereas those in the peripheral row were less covered. However, nymphal mortality was not correlated with the percentage of cardboard tags coverage, although it was correlated with symbiont acquisition. A significant reduction in the percentage of damaged hazelnuts was observed in the treated plot compared to an untreated control, confirming the efficacy of symbiont-targeted control in hazelnut orchards.

Nano-CeO2 for the Photocatalytic Degradation of the Complexing Agent Citric Acid in Cu Chemical Mechanical Polishing

Cu interconnect chemical mechanical polishing (CMP) technology has been continuously evolving, leading to increasingly stringent post-CMP cleaning requirements. To address the environmental pollution caused by traditional post-CMP cleaning solutions, we have explored the use of photocatalytic processes to remove citric acid, which is a commonly used complexing agent for CMP. In this study, CeO2 abrasives, characterized by a hardness of 5.5, are extensively employed in CMP. Importantly, CeO2 also exhibits a suitable band structure with a band gap of 2.27 eV, enabling it to photocatalytically remove citric acid, a commonly used complexing agent in Cu CMP. Additionally, the integration of H2O2, an essential oxidant in Cu CMP, enhances the photocatalytic degradation efficiency. The research indicates that the removal rate of single-phase CeO2 was 1.78 mmol/g/h and the degradation efficiency increased by 40% with the addition of H2O2, attributed to the hydroxyl radicals generated from a Fenton-like reaction between H2O2 and CeO2. These findings highlight the potential of photocatalytic processes to improve organic contaminant removal in post-CMP cleaning, offering a more sustainable alternative to conventional practices.

Evaluating the potential of stabilised betacyanins from fermented red dragon fruit (Hylocereus polyrhizus) drink: Sustainable colouration and antioxidant enhancement of stirred yoghurt

Nowadays, the wide use of synthetic food colourant, Allura Red has elevated negative perceptions among consumers. As food industry players strive towards satisfying consumers’ demands, exploring new sustainable natural colourants with multifunctional properties (like betacyanins) has emerged as a novel concept. This study aimed to evaluate the potential of a functional fruit drink, Improved-FRDFD-dH2O [contained betacyanins of fermented red dragon fruit drink stabilised by 0.4 % xanthan gum and 0.5 % carboxymethyl cellulose hydrocolloid mixture solution and 0.2 % citric acid] to serve as a sustainable and stable functional liquid colourant in yoghurt. The 8-week refrigerated storage study revealed the betacyanins content in the yoghurt added with E162 experienced the lowest stabilities in terms of betacyanins content (>30 % degradation), viscosity (>15 % reduction), pH, LAB viability and antioxidant activity. In contrast, the Improved-FRDFD-dH2O was able to maintain the yoghurt's viscosity, syneresis, pH and LAB viability without any significant change. The betacyanins of Improved-FRDFD-dH2O had excellent stability in the yoghurt (<5 % degradation), showing only a minimal difference (ΔE<1.5) in total colour changes and being able to retain >86 % of the initial antioxidant activity by the end of storage. These findings support the Improved-FRDFD-dH2O as a sustainable functional colourant with antioxidant properties for producing beneficial yoghurt.

Improving the electrochemical performance of nickel-cobalt organic framework by hybridizing with carbon quantum dots

To improve the electrochemical properties of nickel-cobalt metal-organic skeleton materials, two carbon quantum dots (CQDs), namely, CQD-CA and N-doped CQD-CAn, were prepared by using citric acid as carbon source and then introduced into NiCo-MOF to prepare CQDs/NiCo-MOF composites. Through the application of physical characterization and electrochemical analysis methods, such as SEM, TEM, XRD, XPS and BET, it was found that NiCo-MOF@CA and NiCo-MOF@CAn exhibited a nano thinner lamellar structure, higher specific surface area, larger pore structure, and excellent electron transport ability. Especially, by introducing CQDs, the charge could transfer from oxygen to Ni and Co, and there was some higher electron cloud density around active metals Ni and Co in NiCo-MOF@CAn than in NiCo-MOF, effectively activating the metal center Ni and Co. As the result, the specific capacitance of NiCo-MOF@CAn reached 1917.7 F·g−1 at the potential scan rate 5 mV·s−1, significantly higher than that of NiCo-MOF (1173.4 F·g−1) and NiCo-MOF@CA (1489.3 F·g−1). The method might provide an alternative strategy for modulating the morphology, porous structure and the partial electron structure of the target materials by introducing various CQDs.

Methylene blue sorption performance of lignocellulosic peach kernel shells modified with cellulose derivative chitosan as a new bioadsorbent

In this study, adsorption isotherms (Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich) and thermodynamic properties of cationic methylene blue (MB) dye adsorption onto chitosan-coated peach kernel shell waste (CTS-PKSh) from wastewater were investigated. CTS was cross-linked with citric acid (CA) and glutaraldehyde (GA). The adsorbents were characterized by FE-SEM/EDS, FTIR, and particle size distribution. MB adsorption behavior onto the biosorbents was investigated concerning parameters such as adsorbent dosage (0.8–8 g/L), time (0–540 min), pH (3−10), initial dye concentration (50–700 mg/L), and temperature (25–55 °C). The Langmiur qmax and experimentally qe MB adsorption capacities of the new adsorbents were found to be 227.27 and 201 mg/g for CA cross-linked CTS-PKSh (CA@CTS-PKSh) and 111.12 and 96.5 mg/g for GA cross-linked CTS-PKSh (GA@CTS-PKSh), respectively. The results of thermodynamic analysis showed that adsorption was feasible, exothermic, and spontaneous. According to adsorption and recyclability results, CA@CTS-PKSh was more effective for MB removal at a 2 g/L adsorbent dose for an initial dye concentration of 100 mg/L, 25 ± 1 °C, contact time 60 min, and pH 7.

Study on the behavior of AAEMs removal and the evolution of microscopic characteristics in high alkali coal under different acids

ABSTRACT In this paper, the removal behavior of alkali and alkaline earth metals (AAEMs) and the evolution of microscopic characteristics in high alkali coal under the leaching of inorganic and organic acids are studied. The results show inorganic acids have better effect on the removal of AAEMs because of their stronger ability to convert carboxylate and phenol salts into covalent carboxylic acids and phenols. Citric acid has a slightly weaker effect than inorganic acids, and oxalic acid has the least effect. The improvement of slagging characteristics is consistent with the removal ability. Sulfuric acid, hydrochloric acid and citric acid are more effective in enhancing the calorific value of coal, with an enhancement of about 0.60 MJ/kg. After leaching, the pores and cracks in the coal are developed, and the mesopores have a tendency to shift to a lower pore size range. This trend is most pronounced in citric acid leached coal and hydrochloric acid leached coal. Sulfuric acid seriously damage the surface morphology, which results in a tendency of large pore transfer in S-form coal.

Predictive models for estimating the sugar content and organic acids in processed mangoes based on the initial content

SummaryThe quality of processed products can be adversely affected by uncontrollable batches of mangoes, which exhibit heterogeneous characteristics. This study aimed to establish predictive models for sugar and organic acid contents (dependent variables) in processed products using the initial compositions of fresh mangoes. Three mango cultivars (cv. ‘Kent’, cv. ‘Keo Romeat’, and cv. ‘Keo Chen’) were classified as low‐density and high‐density groups. Each group of mangoes at the green‐mature, mid‐ripe, and ripe stages was processed into pasteurised purees, dried slices, and mango chips. Prediction models were established using a mix of simple linear regression (SLR) based on the initial content and Analysis of Variance (ANOVA) to identify the impact of qualitative variables (ripening stage, cultivar‐density, and processing technique). In processed mangoes, 13% sucrose content was estimated to accumulate with the three qualitative variables, whereas glucose and fructose contents decreased from their initial levels by 10% and 7%, respectively. Processing techniques can predict the ratio of sugars/acids (S/A) in processed products, regardless of the ripening stage or cultivar‐density. Similar to S/A, citric acid and malic acid contents in mango products were significantly increased by processing techniques. The initial content and processes were insufficient to predict the final contents of the same parameters in processed mangoes; therefore, some models need to include the effects of ripening stage and cultivar‐density to improve the prediction. These relevant explanatory variables contributed significantly to the development of the models, resulting the accuracy of predictive models with normalised root mean square errors (NRMSEs) lower than 10%, except for malic acid (14.04%). In conclusion, it is feasible to estimate the sugar and acidity levels in processed mangoes, offering promising possibilities for ensuring consistent quality of mango‐based products.

Novel algae-chitosan/alginate beads for efficient basic Fuchsin removal: Synthesis, characterization, adsorption study, mechanism, and optimization

In this study, utilized algae activated with citric acid and lime juice to develop a novel bioadsorbent, The Algae@CS/Alginate beads were formed by encapsulating the activated algae with chitosan and alginate, producing a nanocomposite that is efficient in removing Basic Fuchsin (BF) dye from water. The beads were characterized by means of a diversity of techniques, such as FTIR, XRD, XPS, SEM and determination the surface area via N2 adsorption/desorption isotherm that permitted that the adsorbent has high surface area 124.43 m2/g. The electrical properties of the BF, including its structure and reactivity, were determined by density functional theory (DFT). The MEP data and the molecular orbitals (HOMO and LUMO), as well as the sites of the electrophilic besides nucleophilic attack places, correspond fairly well, according to DFT. The adsorption process was fitted to Langmuir isothermally, and kinetically to pseudo-second-order (PSOE) model. The adsorption mechanism was identified as chemisorption with an adsorption energy of 32.6 kJ/mol. Thermodynamic research shows that the BF adsorption process by Algae@CS/Alginate beads is spontaneous and endothermic because of the positive ΔHo and negative ΔGo. Through numerical optimization of the programmed, the ideal conditions for adsorption were strongminded to be a pH of 8, a dosage of 0.02 g/25 mL for Algae@CS/Alginate beads, and a concentration of 367.27 mg/g of BF. Using the least amount of intended experiments, the adsorption procedure was optimized by the request of Box-Behnken design (BBD) and answer surface methodology (RSM) in Design-Expert software. Adsorbent reusability test results showed that, following eight successive cycles of adsorption and desorption, the adsorbent was stable and that removal efficacy had not decreased. It additionally demonstrated good efficacy, no alteration in chemical conformation, and the same XRD and FTIR data before and after recycle. Analyze the interaction between the Algae@CS/Alginate beads and the BF.

Effect of A-site cation doping on the catalytic oxidation of toluene over mullite catalyst GdMn2O5

Manganese-based mullite (AMn2O5) catalysts are promising for the catalytic oxidation of VOCs, with their oxidation reaction performance being tunable by modifying the composition of the A-site elements. In this work, various manganese-based mullite catalysts (Gd0.9X0.1Mn2O5, X =Sr, Ce, or Ca) with different A-site elements doping were prepared by the citric acid sol–gel method and applied to the catalytic oxidation of toluene. The activity tests indicated that the enhancement of catalytic performance by doping elements was in the order of Sr > Ce > Ca. Notably, the T90 of the Gd0.9Sr0.1Mn2O5 catalyst was 235.6 °C, a lower 37.8 °C than that of the GdMn2O5. Comprehensive characterization and density functional theory (DFT) simulations revealed that Sr doping facilitates the reduction of Mn4+ to Mn3+, increases the electron occupancy of the eg orbitals in octahedral Mn sites, and elevates the Mn-d band center, thus facilitating the adsorption and activation of O2. Additionally, the raised O-p band center caused by Sr doping enhances lattice oxygen mobility. In situ DRIFTS analysis indicated that the introduction of Sr at the A-site optimizes the toluene reaction pathway and accelerates the reaction rate. This work reveals that a simple A-site cation doping strategy can effectively regulate manganese-based mullite catalysts’ electronic structure and surface reaction activity, providing a feasible method for the large-scale preparation of manganese-based mullite catalysts with excellent catalytic performance.

Cellulose-based nanostructured aerogels for leachate decontamination: Towards sustainable phosphorus recovery from sewage sludge ash

Recent EU data confirmed phosphorus as a critical raw material, with efficient recovery from sewage sludge ash presenting challenges, particularly due to the co-dissolution of heavy metals. This work investigated an innovative strategy for the removal of heavy metals from sewage sludge ash derived leachate by using sustainable cellulose nanosponges, synthetized by thermal cross-linking between branched polyethylenimine and 2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO)-oxidized cellulose nanofibers.Lab-scale adsorption tests were conducted with varying sorbent amounts (1, 3 and 10 g/L) in absence or presence of citric acid (10 g/L) across pH values (1.8–10), to assess the removal of metals/metalloids (As, Cu, Cr, Ni, Zn, Fe, Al). P was subsequently precipitated from the decontaminated leachate by adding Ca(OH)2 till target pH.Results showed that cellulose nanosponges were able to adsorb considerable amounts of metallic ions, in particular Fe and Al, under strongly acidic conditions, reducing their percentage by 40% and 30%, respectively. Under optimized conditions (10 g/L of citric acid and 10 g/L of sorbent), the solid precipitate recovered at pH 8 from the decontaminated leachate was compliant with EU regulation 2019/1009 in terms of P2O5 and heavy metals content, suggesting its possible future use as raw material for inorganic fertilizers production.

Effect of postharvest cold storage and subsequent shelf-life on fruit quality and endogenous phytohormones in nectarine fruit

Cold storage is the main approach to extend the postharvest storage period of nectarines. The objective of this study was to investigate fruit quality (flavor and nutrition) and endogenous phytohormone changes and their related transcriptional changes in nectarine fruit after cold storage and subsequent shelf-life, which was performed metabolome, transcriptome and physiological analysis. Cold storage led to irreversible flavor loss due to the inhibition of aroma biosynthesis genes at low temperature. Sugar and organic acid content was affected, with an increase in glucose, fructose and malic acid, and a decrease in sorbitol and citric acid after cold storage or shelf-life. For fruit nutritional quality, total flavonoids or total carotenoids was not significantly affected by cold storage, whereas shelf-life process enhanced their accumulation. The activities of key enzymes for flavonoid biosynthesis, PAL and C4H, were enhanced during the shelf-life process, resulting in a significant increase in flavonoids and enhanced free radicals scavenging capacity. Meanwhile, shelf-life process increased carotenoids content by improving the expression of carotenoid biosynthesis genes PSY, ZDS and ZISO. Additionally, cold storage significantly increased the IAA content and ethylene production, thereby inducing the up-regulation of related signaling transduction genes. The shelf-life process further increased ethylene production, as well as salicylic acid and jasmonic acid content. This study unravels these crucial physiological and associated transcriptional changes of nectarines after cold storage, and may provide a theoretical foundation for improving fruit quality of peaches after cold storage.

Research on high-strength and rapid-hardening magnesium phosphate as a novel bonding material for limestone artifacts

Due to natural erosion and human interference, limestone artifacts often suffer from cracks and gradual detachment. There is a critical need for new bonding materials that possess excellent aging resistance and high compatibility with the artifact substrates. This study investigates the effects of varying proportions of citric acid (CA) and borax (B) as composite retarders on the fundamental properties of magnesium phosphate cement (MPC). Through the application of X-ray diffraction techniques and cold field emission scanning electron microscopy, this research elucidates the mechanisms by which the retarders affect MPC. It was found that a 5 % addition of CA and B significantly reduces the hydration temperature during the early stages of MPC setting, enhances the unconfined compressive strength (reaching 44.3 MPa at 28 days), and allows for controllable setting times (17 minutes). Additionally, the presence of CA was found to delay crystal growth, resulting in an increased quantity of the amorphous phase and higher density of MPC. The optimal MPC formulation was selected as a bonding and repair material for limestone artifacts. For comparative analysis, traditional glutinous rice lime mortar (GL) and commercially available epoxy resin (EP) were tested under wet-dry cycling and UV aging conditions. Results indicated that EP materials demonstrated significant aesthetic incompatibilities and progressive cracking and detachment as aging tests progressed. GL materials exhibited significantly lower bonding strength compared to EP and MPC. In contrast, MPC displayed excellent aging resistance, moderate bonding strength, and a Shore hardness value closely matching that of the limestone substrates. Therefore, high-strength, rapid-hardening MPC represents a valuable and forward-looking solution for the conservation of limestone artifacts.

Characterization and Electrochemical Properties of Carbon Decorated Li3V2(PO4)3 Prepared by Citric Acid Assisted Gel and Heat Treating

Characterization and Electrochemical Properties of Carbon Decorated Li3V2(PO4)3 Prepared by Citric Acid Assisted Gel and Heat Treating

Strategy for treating MAFLD: Electroacupuncture alleviates hepatic steatosis and fibrosis by enhancing AMPK mediated glycolipid metabolism and autophagy in T2DM rats

BackgroundRecent studies have highlighted type 2 diabetes (T2DM) as a significant risk factor for the development of metabolic dysfunction-associated fatty liver disease (MAFLD). This investigation aimed to assess electroacupuncture’s (EA) impact on liver morphology and function in T2DM rats, furnishing experimental substantiation for its potential to stall MAFLD progression in T2DM.MethodsT2DM rats were induced by a high-fat diet and a single intraperitoneal injection of streptozotocin, and then randomly assigned to five groups: the T2DM group, the electroacupuncture group, the metformin group, combination group of electroacupuncture and metformin, combination group of electroacupuncture and Compound C. The control group received a standard diet alongside intraperitoneal citric acid - sodium citrate solution injections. After a 6-week intervention, the effects of each group on fasting blood glucose, lipids, liver function, morphology, lipid droplet infiltration, and fibrosis were evaluated. Techniques including Western blotting, qPCR, immunohistochemistry, and immunofluorescence were employed to gauge the expression of key molecules in AMPK-associated glycolipid metabolism, insulin signaling, autophagy, and fibrosis pathways. Additionally, transmission electron microscopy facilitated the observation of liver autophagy, lipid droplets, and fibrosis.ResultsOur studies indicated that hyperglycemia, hyperlipidemia and IR promoted lipid accumulation, pathological and functional damage, and resulting in hepatic steatosis and fibrosis. Meanwhile, EA enhanced the activation of AMPK, which in turn improved glycolipid metabolism and autophagy through promoting the expression of PPARα/CPT1A and AMPK/mTOR pathway, inhibiting the expression of SREBP1c, PGC-1α/PCK2 and TGFβ1/Smad2/3 signaling pathway, ultimately exerting its effect on ameliorating hepatic steatosis and fibrosis in T2DM rats. The above effects of EA were consistent with metformin. The combination of EA and metformin had significant advantages in increasing hepatic AMPK expression, improving liver morphology, lipid droplet infiltration, fibrosis, and reducing serum ALT levels. In addition, the ameliorating effects of EA on the progression of MAFLD in T2DM rats were partly disrupted by Compound C, an inhibitor of AMPK.ConclusionsEA upregulated hepatic AMPK expression, curtailing gluconeogenesis and lipogenesis while boosting fatty acid oxidation and autophagy levels. Consequently, it mitigated blood glucose, lipids, and insulin resistance in T2DM rats, thus impeding liver steatosis and fibrosis progression and retarding MAFLD advancement.