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1.
Plant J ; 118(6): 1991-2002, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38549549

RESUMO

As a major worldwide root crop, the mechanism underlying storage root yield formation has always been a hot topic in sweet potato [Ipomoea batatas (L.) Lam.]. Previously, we conducted the transcriptome database of differentially expressed genes between the cultivated sweet potato cultivar "Xushu18," its diploid wild relative Ipomoea triloba without storage root, and their interspecific somatic hybrid XT1 with medium-sized storage root. We selected one of these candidate genes, IbNF-YA1, for subsequent analysis. IbNF-YA1 encodes a nuclear transcription factor Y subunit alpha (NF-YA) gene, which is significantly induced by the natural auxin indole-3-acetic acid (IAA). The storage root yield of the IbNF-YA1 overexpression (OE) plant decreased by 29.15-40.22% compared with the wild type, while that of the RNAi plant increased by 10.16-21.58%. Additionally, IAA content increased significantly in OE plants. Conversely, the content of IAA decreased significantly in RNAi plants. Furthermore, real-time quantitative reverse transcription-PCR (qRT-PCR) analysis demonstrated that the expressions of the key genes IbYUCCA2, IbYUCCA4, and IbYUCCA8 in the IAA biosynthetic pathway were significantly changed in transgenic plants. The results indicated that IbNF-YA1 could directly target IbYUCCA4 and activate IbYUCCA4 transcription. The IAA content of IbYUCCA4 OE plants increased by 71.77-98.31%. Correspondingly, the storage root yield of the IbYUCCA4 OE plant decreased by 77.91-80.52%. These findings indicate that downregulating the IbNF-YA1 gene could improve the storage root yield in sweet potato.


Assuntos
Regulação da Expressão Gênica de Plantas , Ipomoea batatas , Proteínas de Plantas , Raízes de Plantas , Fator de Ligação a CCAAT/genética , Fator de Ligação a CCAAT/metabolismo , Ácidos Indolacéticos/metabolismo , Ipomoea batatas/genética , Ipomoea batatas/crescimento & desenvolvimento , Ipomoea batatas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas
2.
J Am Chem Soc ; 146(31): 21357-21366, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39051140

RESUMO

With more flexible active sites and intermetal interaction, dual-atom catalysts (DACs) have emerged as a new frontier in various electrocatalytic reactions. Constructing a typical p-d orbital hybridization between p-block and d-block metal atoms may bring new avenues for manipulating the electronic properties and thus boosting the electrocatalytic activities. Herein, we report a distinctive heteronuclear dual-metal atom catalyst with asymmetrical FeSn dual atom sites embedded on a two-dimensional C2N nanosheet (FeSn-C2N), which displays excellent oxygen reduction reaction (ORR) performance with a half-wave potential of 0.914 V in an alkaline electrolyte. Theoretical calculations further unveil the powerful p-d orbital hybridization between p-block stannum and d-block ferrum in FeSn dual atom sites, which triggers electron delocalization and lowers the energy barrier of *OH protonation, consequently enhancing the ORR activity. In addition, the FeSn-C2N-based Zn-air battery provides a high maximum power density (265.5 mW cm-2) and a high specific capacity (754.6 mA h g-1). Consequently, this work validates the immense potential of p-d orbital hybridization along dual-metal atom catalysts and provides new perception into the logical design of heteronuclear DACs.

3.
Small ; : e2401900, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38798155

RESUMO

Efficient and sustainable energy development is a powerful tool for addressing the energy and environmental crises. Single-atom catalysts (SACs) have received high attention for their extremely high atom utilization efficiency and excellent catalytic activity, and have broad application prospects in energy development and chemical production. M-N4 is an active center model with clear catalytic activity, but its catalytic properties such as catalytic activity, selectivity, and durability need to be further improved. Adjustment of the coordination environment of the central metal by incorporating heteroatoms (e.g., sulfur) is an effective and feasible modification method. This paper describes the precise synthetic methods for introducing sulfur atoms into M-N4 and controlling whether they are directly coordinated with the central metal to form a specific coordination configuration, the application of sulfur-doped carbon-based single-atom catalysts in electrocatalytic reactions such as ORR, CO2RR, HER, OER, and other electrocatalytic reaction are systematically reviewed. Meanwhile, the effect of the tuning of the electronic structure and ligand configuration parameters of the active center due to doped sulfur atoms with the improvement of catalytic performance is introduced by combining different characterization and testing methods. Finally, several opinions on development of sulfur-doped carbon-based SACs are put forward.

4.
Compr Rev Food Sci Food Saf ; 23(1): e13280, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38284571

RESUMO

In recent years, investigations on molecular interaction mechanisms between food proteins and ligands have attracted much interest. The interaction mechanisms can supply much useful information for many fields in the food industry, including nutrient delivery, food processing, auxiliary detection, and others. Molecular simulation has offered extraordinary insights into the interaction mechanisms. It can reflect binding conformation, interaction forces, binding affinity, key residues, and other information that physicochemical experiments cannot reveal in a fast and detailed manner. The simulation results have proven to be consistent with the results of physicochemical experiments. Molecular simulation holds great potential for future applications in the field of food protein-ligand interactions. This review elaborates on the principles of molecular docking and molecular dynamics simulation. Besides, their applications in food protein-ligand interactions are summarized. Furthermore, challenges, perspectives, and trends in molecular simulation of food protein-ligand interactions are proposed. Based on the results of molecular simulation, the mechanisms of interfacial behavior, enzyme-substrate binding, and structural changes during food processing can be reflected, and strategies for hazardous substance detection and food flavor adjustment can be generated. Moreover, molecular simulation can accelerate food development and reduce animal experiments. However, there are still several challenges to applying molecular simulation to food protein-ligand interaction research. The future trends will be a combination of international cooperation and data sharing, quantum mechanics/molecular mechanics, advanced computational techniques, and machine learning, which contribute to promoting food protein-ligand interaction simulation. Overall, the use of molecular simulation to study food protein-ligand interactions has a promising prospect.


Assuntos
Simulação de Dinâmica Molecular , Proteínas , Animais , Ligantes , Simulação de Acoplamento Molecular , Proteínas/química , Ligação Proteica
5.
Food Chem ; 449: 139273, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38599110

RESUMO

The objectives of this study were to modify hordein with gallic acid (GA) in alcohol-free media and to compare the impact of covalent and non-covalent binding on the properties of hordein. Covalent hordein-GA complexes (H-GA) and non-covalent hordein/GA complexes (H/GA) were distinguished by molecular weight, free sulfhydryl groups and free amino groups. Isothermal titration calorimetry (ITC) demonstrated that physical mixing induced non-covalent binding of GA to hordein via hydrogen bonding and hydrophobic interactions, with a lower binding efficiency than covalent ones. Both complexation types led to a structural shift of hordein toward disorder, while grafting of oligomeric GA and alkaline treatment resulted in lower surface hydrophobicity and higher antioxidant activity of H-GA compared to H/GA. The nanoparticles assembled from H-GA had smaller particle sizes and higher physical stability than those formed from H/GA. The results of this study may provide new insights into the modification of hordein by polyphenols.


Assuntos
Ácido Gálico , Ácido Gálico/química , Interações Hidrofóbicas e Hidrofílicas , Ligação de Hidrogênio , Tamanho da Partícula , Antioxidantes/química , Nanopartículas/química , Estrutura Molecular , Etanol/química
6.
Foods ; 13(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38731695

RESUMO

This project aimed to explore the influence of the interaction between ovotransferrin fibrils (OTF) and gum arabic (GA) on the formation mechanism, physicochemical properties, and curcumin delivery of the oleogel-in-water Pickering emulsion. Cryo-scanning electron microscopy results showed that OTF-GA complexes effectively adsorbed on the oil-water interface, generating spatial hindrance to inhibit droplet coalescence. The texture analysis also proved that OTF-GA complexes endowed oleogel-in-water Pickering emulsion with preferable springiness (0.49 ± 0.03 mm), chewiness (0.43 ± 0.07 mJ), and adhesion (0.31 ± 0.01 mJ). By exploring the coalescence stability, droplet size, and rheological properties of OTF-GA complexes-stabilized oleogel-in-water Pickering emulsion (OGPE), the higher coagulation stability, larger average droplet size (46.22 ± 0.08 µm), and stronger gel strength were observed. The microrheological results also exhibited stronger attraction between the OGPE droplets, a more pronounced solid-like structure, and a slower speed of movement than OTF-stabilized oleogel-in-water Pickering emulsion (OPE). Meanwhile, OGPE significantly enhanced the extent of lipolysis, stability, and bioaccessibility of curcumin, suggesting that it possessed superior performance as a delivery system for bioactive substances. This project provided adequate theoretical references for protein-polysaccharide complexes-stabilized oleogel-in-water Pickering emulsion, and contributed to expanding the application of oleogel-in-water Pickering emulsion in the food industry.

7.
Food Chem ; 456: 139975, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-38852456

RESUMO

To enhance the bioavailability of bioactives with varying efficacy in the gastrointestinal tract (GIT), a co-delivery system of solid-in-oil-in-water (S/O/W) emulsion was designed for the co-encapsulation of two bioactives in this paper. S/O/W emulsions were fabricated utilizing fucoxanthin (FUC)-loaded nanoparticles (NPs) as the solid phase, coconut oil containing curcumin (Cur) as the oil phase, and carboxymethyl starch (CMS)/propylene glycol alginate (PGA) complex as the aqueous phase. The high entrapment efficiency of Cur (82.3-91.3%) and FUC (96.0-96.1%) was found in the CMS/PGA complex-stabilized S/O/W emulsions. Encapsulation of Cur and FUC within S/O/W emulsions enhanced their UV and thermal stabilities. In addition, S/O/W emulsions prepared with CMS/PGA complexes displayed good stability. More importantly, the formed S/O/W emulsion possessed programmed sequential release characteristics, delivering Cur and FUC to the small intestine and colon, respectively. These results contributed to designing co-delivery systems for the programmed sequential release of two hydrophobic nutrients in the GIT.


Assuntos
Curcumina , Emulsões , Xantofilas , Emulsões/química , Curcumina/química , Xantofilas/química , Composição de Medicamentos , Nanopartículas/química , Tamanho da Partícula , Estabilidade de Medicamentos , Água/química , Sistemas de Liberação de Medicamentos , Portadores de Fármacos/química
8.
Int J Biol Macromol ; 265(Pt 1): 130805, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38490382

RESUMO

In order to overcome the problem that traditional W1/O/W2 double emulsions do not have targeted release performance, thereby better meeting the health needs of consumers, ovalbumin fibrils/pectin-based bilayer-stabilized double emulsion (OP-BDE) co-encapsulated with Lactobacillus plantarum and curcumin was constructed with pectin as the outer protective shell, which was expected to be used in the development of novel functional foods. The effects of pectin coating on the viability of Lactobacillus plantarum under conditions including storage, pasteurization, freeze-thaw cycles and in vitro simulated digestion were investigated. Results showed that pectin as protective shell could significantly enhance the tolerance of Lactobacillus plantarum to various environmental factors. Besides, the adsorption of pectin endowed OP-BDE with higher lipolysis and stronger protective effect on curcumin, remarkably improving the photostability and bioaccessibility of curcumin. In addition, in vitro simulated gastrointestinal release study indicated that OP-BDE possessed programmed sequential release property, allowing curcumin and Lactobacillus plantarum to be released in small intestine and colon, respectively. OP-BDE is the first reported co-delivery emulsion system with programmed release characteristic. This study provides new insights into OP-BDE in constructing co-delivery systems and programmed sequential release of active substances, and has potential reference and application value in actual food production.


Assuntos
Curcumina , Lactobacillus plantarum , Emulsões , Curcumina/farmacologia , Pectinas , Trato Gastrointestinal
9.
World Neurosurg ; 187: e1025-e1039, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38750888

RESUMO

OBJECTIVE: This study aims to develop a nomogram model incorporating lactate-to-albumin ratio (LAR) to predict the prognosis of hospitalized patients with intracerebral hemorrhage (ICH) and demonstrate its excellent predictive performance. METHODS: A total of 226 patients with ICH from the Medical information mart for intensive care III (MIMIC Ⅲ) database were randomly split into 8:2 ratio training and experimental groups, and 38 patients from the eICU-CRD for external validation. Univariate and multivariate Cox proportional hazards regression analysis was performed to identify independent factors associated with ICH, and multivariate Cox regression was used to construct nomograms for 7-day and 14-day overall survival (OS). The performance of nomogram was verified by the calibration curves, decision curves, and receiver operating characteristic (ROC) curves. RESULTS: Our study identified LAR, glucose, mean blood pressure, sodium, and ethnicity as independent factors influencing in-hospital prognosis. The predictive performance of our nomogram model for predicting 7-day and 14 -day OS (AUCs: 0.845 and 0.830 respectively) are both superior to Oxford Acute Severity of Illness Score, Simplified acute physiology score II, and SIRS (AUCs: 0.617, 0.620 and 0.591 and AUCs: 0.709, 0.715 and 0.640, respectively) in internal validation, and also demonstrate favorable predictive performance in external validation (AUCs: 0.778 and 0.778 respectively). CONCLUSIONS: LAR as a novel biomarker is closely associated with an increased risk of in-hospital mortality of patients with ICH. The nomogram model incorporating LAR along with glucose, mean blood pressure, sodium, and ethnicity demonstrate excellent predictive performance for predicting the prognosis of 7- and 14-day OS of hospitalized patients with ICH.


Assuntos
Hemorragia Cerebral , Ácido Láctico , Nomogramas , Humanos , Feminino , Masculino , Hemorragia Cerebral/sangue , Hemorragia Cerebral/mortalidade , Hemorragia Cerebral/diagnóstico , Prognóstico , Pessoa de Meia-Idade , Idoso , Ácido Láctico/sangue , Hospitalização , Biomarcadores/sangue , Mortalidade Hospitalar , Valor Preditivo dos Testes , Albumina Sérica/análise , Idoso de 80 Anos ou mais
10.
Environ Pollut ; 357: 124454, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38936035

RESUMO

Despite biological wastewater treatment processes (e.g., sequencing batch reactors (SBR)) being able to reduce the dissemination of antibiotic resistance genes (ARGs), the variation of ARGs under exogenous pollutant stress is an open question. This work investigated the impacts of para-chloro-meta-xylenol (PCMX, typical antibacterial contaminants) on ARGs spread in long-term SBR operation. Although the SBR process inherently decreased ARGs abundance, the presence of PCMX substantially amplified both the prevalence (mainly multidrug) and abundance of total ARGs (1.17-fold of the control). Further analysis demonstrated that PCMX disintegrated sludge structures as well as increased membrane permeability, facilitating the release of mobile genetic elements and subsequent horizontal transfer of ARGs. In addition, PCMX selectively enriched potential ARG hosts, notably Nitrospira and Candidatus Accumulibacter, which predominantly served as multidrug ARG hosts. Concurrently, the self-adaptive functions of ARGs hosts in the PCMX-exposed SBR system were activated via quorum sensing, two-component regulatory system, ATP-binding cassette transporters, and bacterial secretion system. The upregulation of these metabolic pathways also contributed to the dissemination of ARGs.


Assuntos
Eliminação de Resíduos Líquidos , Águas Residuárias , Águas Residuárias/microbiologia , Microbiota/efeitos dos fármacos , Xilenos , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos/genética , Poluentes Químicos da Água/metabolismo , Reatores Biológicos , Genes Bacterianos , Bactérias/genética , Bactérias/metabolismo , Bactérias/efeitos dos fármacos
11.
ACS Nano ; 18(20): 13286-13297, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38728215

RESUMO

The ideal interface design between the metal and substrate is crucial in determining the overall performance of the alkyne semihydrogenation reaction. Single-atom alloys (SAAs) with isolated dispersed active centers are ideal media for the study of reaction effects. Herein, a charge-asymmetry "armor" SAA (named Pd1Fe SAA@PC), which consists of a Pd1Fe alloy core and a semiconducting P-doped C (PC) shell, is rationally designed as an ideal catalyst for the selective hydrogenation of alkynes with high efficiency. Multiple spectroscopic analyses and density functional theory calculations have demonstrated that Pd1Fe SAA@PC is dual-regulated by lattice tensile and Schottky effects, which govern the selectivity and activity of hydrogenation, respectively. (1) The PC shell layer applied an external traction force causing a 1.2% tensile strain inside the Pd1Fe alloy to increase the reaction selectivity. (2) P doping into the C-shell layer realized a transition from a p-type semiconductor to an n-type semiconductor, thereby forming a unique Schottky junction for advancing alkyne semihydrogenation activity. The dual regulation of lattice strain and the Schottky effect ensures the excellent performance of Pd1Fe SAA@PC in the semihydrogenation reaction of phenylethylene, achieving a conversion rate of 99.9% and a selectivity of 98.9% at 4 min. These well-defined interface modulation strategies offer a practical approach for the rational design and performance optimization of semihydrogenation catalysts.

12.
Adv Mater ; 36(33): e2404665, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38923612

RESUMO

Double-atom catalysts (DACs) with asymmetric coordination are crucial for enhancing the benefits of electrochemical carbon dioxide reduction and advancing sustainable development, however, the rational design of DACs is still challenging. Herein, this work synthesizes atomically dispersed catalysts with novel sulfur-bridged Cu-S-Ni sites (named Cu-S-Ni/SNC), utilizing biomass wool keratin as precursor. The plentiful disulfide bonds in wool keratin overcome the limitations of traditional gas-phase S ligand etching process and enable the one-step formation of S-bridged sites. X-ray absorption spectroscopy (XAS) confirms the existence of bimetallic sites with N2Cu-S-NiN2 moiety. In H-cell, Cu-S-Ni/SNC shows high CO Faraday efficiency of 98.1% at -0.65 V versus RHE. Benefiting from the charge tuning effect between the metal site and bridged sulfur atoms, a large current density of 550 mA cm-2 can be achieved at -1.00 V in flow cell. Additionally, in situ XAS, attenuated total reflection surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS), and density functional theory (DFT) calculations show Cu as the main adsorption site is dual-regulated by Ni and S atoms, which enhances CO2 activation and accelerates the formation of *COOH intermediates. This kind of asymmetric bimetallic atom catalysts may open new pathways for precision preparation and performance regulation of atomic materials toward energy applications.

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