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5‐Hydroxymethylfurfural (HMF) was transformed into 2,5‐diformylfuran (DFF) with nitric acid as the oxidant. The initial HMF content was as high as 12.5 wt %, and water was the sole solvent. This is an intensely exothermic reaction along with the emission of NO2 gas. A high DFF yield of 83.2 % was achieved if the oxidation ability of nitric acid matched with the requirement of target oxidation reaction while mismatched those of side reactions by regulating the initial concentration of nitric acid (59.5 wt %) and reaction temperature (50–60 °C). The oxidation reaction of HMF, overoxidation of HMF, and skeleton‐cracking reaction of FDCA preferred concentrated HNO3, hot HNO3, and concentrated or hot HNO3, respectively. After liquid‐liquid extraction, filtration, and column chromatography, light‐yellow DFF powders with purity of 92.1 wt % and isolated yield of 40.2 % were obtained and confirmed by NMR, FTIR, UV‐Vis, and elemental analysis. HMF was the dominant impurity due to its affinity to DFF. In addition, chromogenic substances were obtained as a byproduct, and they were potential pH indicators. These chromogenic substances had highly conjugated molecular structures, and they were generated via successive β‐protonation‐based ring‐opening reaction of HMF, aldol reaction, and dehydration reaction. [ABSTRACT FROM AUTHOR]

For the controllable transformation of C3–6 diols in ethylene glycol (EG), a H-Beta zeolite catalyst was modified with NH3via incomplete desorption. 60.8% of acid sites on the zeolite were deactivated, but the ratio of strong acid sites was obviously increased. With 1,2-pentanediol (PDO) as a representative large-carbon-number diol, the undesirable acetalization and oligomerization reactions of EG were suppressed in the EG-PDO reaction system over the modified catalyst due to their dependency on total acid sites. NH3-TPD and FTIR results proved that Lewis acid sites on the modified zeolite were eliminated after modification, resulting in the suppression of acetalization and oligomerization reactions. In contrast, a portion of strong Brønsted acid sites still remained, ensuring the catalytic transformation of PDO. Only 8.2% of EG was consumed after 8 h reaction, and the conversion of PDO could reach 84.3%. The loading of NH3 on the surface of zeolite pores led to diffusion resistance, slightly decreasing the reaction rate of PDO without affecting the reaction selectivity. The catalytic reactions of other C3–6 diols in EG followed similar principles, and the selectivity to aldehydes or ketone was improved over this modified catalyst. Non-diol biomass hydrogenation products such as glycerol had a negative influence on the selectivity, so these components should be isolated before the reactions. This catalyst could be reused at least 5 times, and the conversion of PDO slightly decreased. This work sheds light on the relationships between the acid properties of the catalyst and different reactions of diols. [ABSTRACT FROM AUTHOR]

This study aimed to extract pectin from local Majiayou pomelo (Citrus grandis (L.) Osbeck) peel in Jiangxi province with distilled water, hydrochloric acid and citric acid, respectively, and analyze the physicochemical components of pectin and its adsorption properties on Pb(II), and explicit the effect of adsorption parameters (initial pH value, initial ion concentration, adsorption time) on Pb (II) and its adsorption mechanism by adsorption isotherms and adsorption kinetics. The results showed that the yield of pectin by citric acid extraction (CEP) was highest (28.62%), followed by hydrochloric acid extraction (HEP) and distilled water extraction (WEP). In addition, the esterification degree (58.20%) and molecular weight (598.40 ku) of CEP were significantly lower than those of WEP and HEP (P<0.05), indicating that CEP had more carboxyl and higher solubility. The three pectins showed optimal adsorption of Pb (II) at initial pH 5.0, and reached equilibrium after 120 min adsorption. In addition, the adsorption capacity of CEP on Pb (II) was significantly higher than that by WEP and HEP. The adsorption isotherms of the three pectins were in accordance with Langmuir monolayer adsorption model, and the adsorption kinetics of the three pectins was consistent with pseudo first-order kinetics model. The adsorptions of three pectins on Pb (II) were the result of physical and chemical adsorption. Conclusion: The physicochemical properties of pectin and its adsorption capacity on Pb (II) were closely related to the extraction method, and CEP has a high adsorption capacity on Pb (II), which could be used as a low-cost, efficient, natural and environmental friendly adsorbent for removal of Pb (II). [ABSTRACT FROM AUTHOR]

BACKGROUND The application of Pickering emulsions stabilized by food‐derived particles is of great interest, studies have focused on development of natural functional emulsifiers from agricultural byproducts. Dietary fiber (DF) has been recognizing for its excellent physiological functions. Moreover, physicochemical properties of pomelo peel DF (PDF) make it a potential emulsifier. However, pristine PDF is not suitable as emulsifier due to its compact physical structure and high hydrophobicity, which seriously limits its utilization. The objective of the study was to investigate the effects of cellulase on physicochemical properties of PDF and to illustrate the feasibility of cellulase modified PDF (MPDF) as natural functional emulsifier. RESULTS: Cellulase modification significantly improved (P < 0.05) specific surface area, water‐holding capacity/oil‐holding capacity, viscoelasticity, hydrophobicity, and pore structure while decreased crystallinity index and particle size of PDF. Emulsion could remain stable over 30 days as MPDF concentrations up to 1 wt% and oil/water ratio 3:7. The appearance stability of emulsions was not influenced by temperature (4–60 °C), pH (3.0–12.0), and ion concentration (0–200 mmol L−1) which was similar to Pickering emulsions. The mechanism of MPDF as an emulsifier was mainly attributed to the combination of Pickering effect and the three‐dimensional network. In addition, MPDF showed higher antioxidant capacity in emulsions than other classical emulsifiers. CONCLUSION: The results illustrated that MPDF has a favorable feasibility for preparation of stable Pickering‐type emulsions, which will be a practical support for application of PDF as a natural functional emulsifier and will be helpful to realize the resource utilization of DF in pomelo industries. © 2022 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

We have previously demonstrated that General Control Non-derepressible 1 (AtGCN1) is essential for translation inhibition under cold stress through interacting with GCN2 to phosphorylate eukaryotic translation initiation factor 2 (eIF2). Here, we report that the flower time of the atgcn1 mutant is later than that of the wild type (WT), and some siliques of atgcn1 cannot develop and produce seeds. Total and polysomal RNA of atgcn1-1 and wild type (WT) after cold treatments were sequenced. The sequencing results show that the mutation of atgcn1 selectively alters the expression of genes at both transcriptional and translational levels. The classification of AtGCN1 target genes reveals that AtGCN1 regulated gens are involved in flower development, seed dormancy and seed development, response to osmotic stress, amino acid biosynthesis, photosynthesis, cell wall organization, protein transport and localization, lipid biosynthesis, transcription, macroautophagy, proteolysis and cell death. Further analysis of AtGCN1 regulated genes at translational levels shows that the Kozak sequence and uORFs (upstream open reading frame) of transcripts affect translation selection. These results show that AtGCN1 is required for the expression of selective genes in Arabidopsis. [ABSTRACT FROM AUTHOR]

TMSCFX2 (X = Cl, Br; TMS = trimethylsilyl) have been developed as halofluorocarbene (CFX, X = Cl, Br) precursors for [2+1] cyclopropanation with alkenes. Structurally diverse halofluorocyclopropanes were obtained in good to excellent yields. It was found that the reactivity order of the three halofluorocarbene reagents (TMSCF2Br, TMSCFCl2, and TMSCFBr2) in halofluorocyclopropanation with 1,1-diphenylethylene can be very different under different reaction conditions. [ABSTRACT FROM AUTHOR]

Nowadays, freshwater resources are facing numerous crises and pressures, resulting from both artificial and natural process, so it is crucial to predict the water quality for the department of water environment protection. This paper proposes a hybrid optimized algorithm involving a particle swarm optimization (PSO) and genetic algorithm (GA) combined BP neural network that can predict the water quality in time series and has good performance in Beihai Lake in Beijing. The data sets consist of six water quality parameters which include Hydrogen Ion Concentration (pH), Chlorophyll-a (CHLA), Hydrogenated Amine (NH4H), Dissolved Oxygen (DO), Biochemical Oxygen Demand (BOD), and electrical conductivity (EC). The performance of the model was assessed through the absolute percentage error ( A P E m a x ), the mean absolute percentage error (MAPE), the root mean square error (RMSE), and the coefficient of determination ( R 2 ). Study results show that the model based on PSO and GA to optimize the BP neural network is able to predict the water quality parameters with reasonable accuracy, suggesting that the model is a valuable tool for lake water quality estimation. The results show that the hybrid optimized BP model has a higher prediction capacity and better robustness of water quality parameters compared with the traditional BP neural network, the PSO-optimized BP neural network, and the GA-optimized BP neural network. [ABSTRACT FROM AUTHOR]

The development of biomaterials with the potential to accelerate wound healing is a great challenge in biomedicine. In this study, four types of samples including pepsin soluble collagen sponge (PCS), acid soluble collagen sponge (ACS), bovine collagen electrospun I (BCE I) and bovine collagen electrospun II (BCE II) were used as wound dressing materials. We showed that the PCS, ACS, BCE I and BCE II treated rats increased the percentage of wound contraction, reduced the inflammatory infiltration, and accelerated the epithelization and healing. PCS, ACS, BCE I, and BCE II significantly enhanced the total protein and hydroxyproline level in rats. ACS could induce more fibroblasts proliferation and differentiation than PCS, however, both PCS and ACS had a lower effect than BCE I and BCE II. PCS, ACS, BCE I, and BCE II could regulate deposition of collagen, which led to excellent alignment in the wound healing process. There were similar effects on inducing the level of cytokines including EGF, FGF, and vascular endothelial marker CD31 among these four groups. Accordingly, this study disclosed that collagens (PCS and ACS) from tilapia skin and bovine collagen electrospun (BCE I and BCE II) have significant bioactivity and could accelerate wound healing rapidly and effectively in rat model. [ABSTRACT FROM AUTHOR]

Snakes are widely farmed in China for medicinal purposes and as pets worldwide. Acanthamoeba spp., Blastocystis spp., and Cyclospora spp. are significant zoonotic pathogens frequently discovered in various animals, causing diseases with global public health implications. However, their prevalence and zoonotic potential in snakes remain poorly understood. In this study, 812 snake faecal samples were collected across 28 China provinces. The partial small subunit (SSU) rRNA gene was amplified using polymerase chain reaction (PCR) to assess evolutionary relationships and genetic characterization. Detection rates for Acanthamoeba spp., Blastocystis spp., and Cyclospora spp. were 6.40 %, 3.33 %, and 2.71 %, respectively. Sequencing and phylogenetic analysis revealed that Cyclospora isolates were closely related to those found in humans and cattle. Subtyping for Blastocystis species identified two zoonotic subtypes (ST4, ST6) and four host-specific subtypes (ST10, ST15, ST21, ST42). Multiple Acanthamoeba genotypes were detected, including T4, T11, and T13. Furthermore, species, age, and living conditions are key risk factors. This study provides valuable insights into these infections in snakes and underscores the need for proper hygiene and One Health measures to reduce zoonotic transmission and environmental contamination., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier B.V. All rights reserved.)