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1.
Food Funct ; 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39453315

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive behavioral and cognitive impairments. Despite growing evidence of the neuroprotective action of omega-3 polyunsaturated fatty acids (PUFAs), the effects and mechanism of omega-3 PUFAs on AD control are yet to be clarified. By crossing male heterozygous fat-1 mice with female APP/PS1 mice, we assessed whether elevated tissue omega-3 PUFA levels could alleviate AD progression and their underlying mechanism among the offspring WT, APP/PS1 and APP/PS1 × fat-1 groups at various stages. We found that the fat-1 transgene significantly increased brain omega-3 PUFA and docosahexaenoic acid (DHA) levels, and cognitive deficits together with brain Aß-40 and Aß-42 levels in 6-month-old APP/PS1 × fat-1 mice were significantly lower than those in APP/PS1 mice. Subsequently, the tandem mass tag (TMT) method revealed the elevated expression of cortex and hippocampus myelin-associated glycoprotein (MAG) in APP/PS1 × fat-1 mice at 2-6 months. Furthermore, GO and KEGG pathway enrichment analysis suggested that the MAG-related myelin sheath pathway and its interaction with AD were regulated by omega-3 PUFAs. Moreover, subsequent western blot assays showed that both increased endogenous omega-3 levels and in vitro supplemented DHA up-regulated MAG expression, and the AD-protective effects of DHA on LPS-induced BV2 cells were significantly weakened when MAG was inhibited by si-RNA transfection. In summary, our study suggested that omega-3 PUFAs might protect against AD by up-regulating MAG expression.

2.
Future Sci OA ; 10(1): 2409054, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-39392083

RESUMO

Aim: To evaluate the clinic-pathological features and prognostic value regarding PSMD14 in cancers.Materials & methods: Literature was gathered from public databases until 22 June 2023 to analyze data on survival rates and clinicopathological characteristics associated with PSMD14. TCGA and GEO data were also utilized for validation.Results: Eight reports on seven types of tumors showed that high PSMD14 expression was linked to poorer overall survival and disease-free survival. PSMD14 expression also correlated with larger tumor size, differentiation and metastasis, as well as the effectiveness of various chemotherapy drugs.Conclusion: PSMD14 could serve as a potential biomarker of poor prognosis in cancers, including lung cancer, head and neck squamous cell carcinoma, ovarian cancer, breast cancer and hepatocellular carcinoma.


Cancer is harmful to human health. We need to find a marker that can help us identify and treat cancer. PSMD14 is one such marker. The expression of PSMD14 is higher in cancer tissues than in normal tissues. The expression of PSMD14 is associated with the sensitivity of cancer to anticancer drugs. Cancers with high PSMD14 expression tend to be more severe. Cancers with low expression of PSMD14 tend to have a longer survival time.

3.
Int J Biol Macromol ; 281(Pt 3): 136457, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39389517

RESUMO

The traditional process of producing yuba films from soybeans strictly limits the development of its industrial production due to the numerous processes and intricate procedures involved. In this study, a straight-forward and effective strategy was proposed to substitute soymilk with an emulsion made from soybean protein isolate and soybean oil for the formation of yuba films. It was found that the mechanical properties of yuba films formed through this method were controlled by the concentrations of proteins and oils. As the protein concentrations increased, a higher ratio of adsorbed proteins adhered to the surface of oil droplets, which in turn facilitated the recombination of proteins and the formation of larger aggregates during heat incubation. The rheological properties and interfacial adsorption behavior suggested that larger protein aggregates exhibited a greater diffusion rate and were more prone to unfolding and re-crosslinking at the interface through heat induction, resulting in the formation of stronger protein networks. Confocal laser scanning microscope images revealed a notable increase in the density of oil distribution within the yuba films as the oil concentrations in the pre-emulsion rose. Combined with the dense protein network formed at high protein concentrations, the elongation of yuba films was significantly increased.

4.
J Am Chem Soc ; 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39454113

RESUMO

Lithium metal batteries (LMBs) with high energy density are perceived as the most promising candidates to enable long-endurance electrified transportation. However, rapid capacity decay and safety hazards have impeded the practical application of LMBs, where the entangled complex degradation pattern remains a major challenge for efficient battery design and engineering. Here, we present an interpretable framework to learn the accelerated aging of LMBs with a comprehensive data space containing 79 cells varying considerably in battery chemistries and cell parameters. Leveraging only data from the first 10 cycles, this framework accurately predicts the knee points where aging starts to accelerate. Leaning on the framework's interpretability, we further elucidate the critical role of the last 10%-depth discharging on LMB aging rate and propose a universal descriptor based solely on early cycle electrochemical data for rapid evaluation of electrolytes. The machine learning insights also motivate the design of a dual-cutoff discharge protocol, which effectively extends the cycle life of LMBs by a factor of up to 2.8.

5.
J Am Chem Soc ; 146(42): 28961-28972, 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39279160

RESUMO

Pressure-induced emission (PIE) is a compelling phenomenon that can activate luminescence within nonemissive materials. However, PIE in nonemissive organic materials has never been achieved. Herein, we present the first observation of PIE in an organic system, specifically within nonemissive azobenzene derivatives. The emission of 1,2-bis(4-(anthracen-9-yl)phenyl)diazene was activated at 0.52 GPa, primarily driven by local excitation promotion induced by molecular conformational changes. Complete photoisomerization suppression of the molecule was observed at 1.5 GPa, concurrently accelerating the emission enhancement to 3.53 GPa. Differing from the key role of isomerization inhibition in conventional perception, our findings demonstrate that the excited-state constituent is the decisive factor for emission activation, providing a potentially universal approach for high-efficiency azobenzene emission. Additionally, PIE was replicated in the analogue 1,2-bis(4-(9H-carbazol-9-yl)phenyl)diazene, confirming the general applicability of our findings. This work marks a significant breakthrough within the PIE paradigm and paves the novel high-pressure route for crystalline-state photoisomerization investigation.

6.
Angew Chem Int Ed Engl ; : e202414810, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39322938

RESUMO

Developing ionic copper-iodine clusters with multiple emitting is crucial for enriching lighting and display materials with various colors. However, the luminescent properties of traditional ionic copper-iodine clusters are often closely associated with low-energy cluster-centered triplet emission, which will redshift further as the Cu⋅⋅⋅Cu bond length decreases. This article utilizes a pressure-treated strategy to achieve an anomalous pressure-induced blue-shifted luminescence phenomenon in ionic Cu4I6(4-dimethylamino-1-ethylpyridinium)2 crystals for the first time, which is based on dominant through-space charge-transfer (TSCT). Herein, we reveal that the more advantageous through-space interactions in the competition between cuprophilic interactions and through-space interactions can lead to a blue-shifted luminescence. High-pressure angle-dispersive X-ray diffraction and high-pressure infrared experiments show that the enhanced through-space interactions mainly originate from forming new intermolecular C-H⋅⋅⋅I hydrogen bonds and the enhancement of van der Waals interactions between organic cations and anionic clusters. Theoretical calculations and experimental studies of excited-state dynamics confirm that the blue-shifted emission is due to the increased energy gap between the excited triplet and ground states caused by the electron delocalization under stronger through-space interactions. This work deepens previous understanding and provides a new avenue to design and synthetic ionic copper-iodine clusters with high-energy TSCT emission.

7.
Research (Wash D C) ; 7: 0476, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39286735

RESUMO

The interaction between organic and inorganic components in metal hybrid perovskites fundamentally determines the intrinsic optoelectronic performance. However, the underlying interaction sites have still remained elusive, especially for those non-hydrogen-bonded hybrid perovskites, thus largely impeding materials precise design with targeted properties. Herein, high pressure is utilized to elucidate the interaction mechanism between organic and inorganic components in the as-synthesized one-dimensional hybrid metal halide (DBU)PbBr3 (DBU = 1,8-diazabicyclo [5.4.0] undec-7-ene). The interaction sites are identified to be the N from DBU and the Br from inorganic framework by the indicative of enhanced Raman mode under high pressure. The change in interaction strength is indeed derived from the pressure modulation on both distance and spatial arrangement of the nearest Br and N, rather than traditional hydrogen-bonding effect. Furthermore, the enhanced interaction increased charge transfer, resulting in a cyan emission with photoluminescence quantum yields (PLQYs) of 86.6%. The enhanced cyan emission is particularly important for underwater communication due to the much less attenuation in water than at other wavelength emissions. This study provides deep insights into the underlying photophysical mechanism of non-hydrogen-bonded hybrid metal halides and is expected to impart innovative construction with superior performance.

8.
Nat Commun ; 15(1): 7778, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39237586

RESUMO

Luminescent materials that simultaneously embody bright singlet and triplet excitons hold great potential in optoelectronics, signage, and information encryption. However, achieving high-performance white-light emission is severely hampered by their inherent unbalanced contribution of fluorescence and phosphorescence. Herein, we address this challenge by pressure treatment engineering via the hydrogen bonding cooperativity effect to realize the mixture of n-π*/π-π* transitions, where the triplet state emission was boosted from 7% to 40% in isophthalic acid (IPA). A superior white-light emission based on hybrid fluorescence and phosphorescence was harvested in pressure-treated IPA, and the photoluminescence quantum yield was increased to 75% from the initial 19% (blue-light emission). In-situ high-pressure IR spectra, X-ray diffraction, and neutron diffraction reveal continuous strengthening of the hydrogen bonds with the increase of pressure. Furthermore, this enhanced hydrogen bond is retained down to the ambient conditions after pressure treatment, awarding the targeted IPA efficient intersystem crossing for balanced singlet/triplet excitons population and resulting in efficient white-light emission. This work not only proposes a route for brightening triplet states in organic small molecules, but also regulates the ratio of singlet and triplet excitons to construct high-performance white-light emission.

9.
Phytomedicine ; 135: 155554, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-39341127

RESUMO

BACKGROUND: The long history of clinical experience in China have confirmed the effectiveness of traditional Chinese medicine (TCM) in treating prostate cancer (PCa). Until now, several bioactive compounds with anti-PCa potential, such as curcumin, gallic acid, and quercetin, have been extracted from TCM. Recent studies have shown that encapsulating these TCM bioactive compounds into nano-delivery system enhanced their bioavailability and improved their ability to target PCa tumors. PURPOSE: This review aims to summarize the anti-PCa effects and molecular mechanisms of TCM bioactive compounds and discuss the clinical application prospects and future research trends of nano-delivery system based on these compounds. METHODS: Literatures focusing on the treatment of PCa using traditional Chinese medicine compounds via nano-drug delivery system were searched from Electronic databases, including PubMed, Web of Science, and Scopus until December 2023. RESULTS: Polyphenols, alkaloids, terpenes, and quinones exhibit anti-PCa effects through various pathways. Notably, compounds like curcumin, gallic acid, quercetin, and tanshinone have been extensively studied in nano-delivery systems for anti-PCa purpose. Nano-delivery systems enhance the biological activity of free compounds and reduce toxic side effects, as well. Commonly used nanomaterials for delivering TCM compounds include polymer nanomaterials, liposomes, solid lipid nanoparticles, nanostructured lipid carriers, and niosomes. CONCLUSION: Research on nano-delivery systems for TCM bioactive compounds holds promising prospects for anti-PCa therapy. However, extensive clinical trials are necessary to evaluate the effectiveness and safety of these nanodrugs.

10.
Angew Chem Int Ed Engl ; : e202415383, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39322614

RESUMO

Sulfur dots (SDs) have emerged as promising photoluminescence (PL) materials owing to their intrinsic merits such as abundant electronic effects, outstanding biocompatibility and available photocatalytic activity. Typically based on quantum confinement effects, SDs are reported usually confined emission in blue-to-green region. However, it is challenging to achieve their broad emission tunability in the visible region, restricted by inherent band gap of bulk sulfur (ca. 2.79 eV). Herein, we present white-light-emitting SDs achieved by surface charge engineering that hybridizes the surface of SDs with oleylamine. The resulting SDs exhibit broadband emissions (full width at half maximum of 187 nm) with PL quantum yields of up to 12.1% and Commission International de I'Eclairage color coordinates of (0.27, 0.32). Detailed experimental and calculation results reveal that the strong orbital coupling between oleylamine and sulfur on the hybrid surfaces of the SDs causes electron delocalization, leading to the generation of low-energy charge transfer (CT) states. These CT states are highly sensitive to sulfur-oleylamine hybrid structures, which complicate the transition dynamics and promote multi-energy emission, accounting for efficient white-light emission. The demonstration of white-light SDs based on surface charge engineering is an important step towards the development of sulfur-based PL materials.

11.
J Phys Chem Lett ; 15(39): 9939-9944, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39312401

RESUMO

Hydrazine borane (N2H4BH3, HB), a typical B-N-H compound with very high hydrogen content (15.4 wt %), is regarded as an efficient hydrogen storage material. However, during the pyrolysis at ambient pressure, solid HB decomposes, losing ∼30 wt %, which is rationalized by the evolution of hydrazine (N2H4). Here, high pressure is introduced as an analogous catalyst role that enable to optimize the decomposition pathway of solid HB. This approach improves the H atomic utilization to over 95%. Energy-dispersive spectroscopy (EDS) analysis indicates that pressure inhibits the production of N2H4, in-situ high-pressure-high-temperature Raman and in-situ high-pressure Infrared (IR) spectra, Density functional theory (DFT) calculation, and Hirshfeld analysis reveal that this inhibition is a consequence of pressure-enhanced dihydrogen and BN bonds. The superior hydrogen release properties of HB under high pressure make it a candidate for use in the synthesis of superconductor CeH9 as a hydrogen source.

12.
Angew Chem Int Ed Engl ; 63(46): e202412756, 2024 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-39107973

RESUMO

Simultaneous enhancement of free excitons (FEs) emission and self-trapped excitons (STEs) emission remains greatly challenging because of the radiative pathway competition. Here, a significant fluorescence improvement, associated with the radiative recombination of both FEs and STEs is firstly achieved in an unconventional ACI-type hybrid perovskite, (ACA)(MA)PbI4 (ACA=acetamidinium) crystals with {PbI6} octahedron units, through hydrostatic pressure processing. Note that (ACA)(MA)PbI4 exhibits a 91.5-fold emission enhancement and considerable piezochromism from green to red in a mild pressure interval of 1 atm to 2.5 GPa. The substantial distortion of both individual halide octahedron and the Pb-I-Pb angles between two halide octahedra under high pressure indeed determines the pressure-tuning localized excitons behavior. Upon higher pressure, photocurrent enhancement is also observed, which is attributed to the promoted electronic connectivity in (ACA)(MA)PbI4. The anisotropic compaction reduces the distance between neighboring organic molecules and {PbI6} octahedra, leading to the enhancement of hydrogen bonding interactions. This work not only offers a deep understanding of the structure-optical relationships of ACI-type perovskites, but also presents insights into breaking the limits of luminescent efficiency by pressure-suppressed nonradiative recombination.

13.
Food Chem ; 460(Pt 3): 140818, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39137576

RESUMO

The effects of adsorption behavior and assembly mechanism of proteins and lipids at the interface on the formation of yuba films were investigated. The thickness of yuba films increased rapidly from nano to micro scale within minutes according to the scanning electron microscopy (SEM) images. The confocal laser scanning microscope (CLSM), SEM images, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that the formation of protein aggregates (40-100 nm) was an essential requirement for the development of yuba. Meanwhile, a relatively loose spatial structure was formed by protein aggregates under the influence of water vapor. This structure served as the foundation for incorporating lipids. Interfacial adsorption kinetics indicated that increasing the concentration (from 3 to 9 mg/mL) of protein aggregates enhanced the rearrangement rate. This finding demonstrated that the variations of interfacial protein aggregate concentration were a crucial factor leading to the non-linear growth of film thickness.


Assuntos
Agregados Proteicos , Adsorção , Cinética , Embalagem de Alimentos/instrumentação , Propriedades de Superfície , Lipídeos/química , Proteínas/química
14.
World J Gastroenterol ; 30(29): 3511-3533, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39156500

RESUMO

BACKGROUND: Calculus bovis (CB), used in traditional Chinese medicine, exhibits anti-tumor effects in various cancer models. It also constitutes an integral component of a compound formulation known as Pien Tze Huang, which is indicated for the treatment of liver cancer. However, its impact on the liver cancer tumor microenvironment, particularly on tumor-associated macrophages (TAMs), is not well understood. AIM: To elucidate the anti-liver cancer effect of CB by inhibiting M2-TAM polarization via Wnt/ß-catenin pathway modulation. METHODS: This study identified the active components of CB using UPLC-Q-TOF-MS, evaluated its anti-neoplastic effects in a nude mouse model, and elucidated the underlying mechanisms via network pharmacology, transcriptomics, and molecular docking. In vitro assays were used to investigate the effects of CB-containing serum on HepG2 cells and M2-TAMs, and Wnt pathway modulation was validated by real-time reverse transcriptase-polymerase chain reaction and Western blot analysis. RESULTS: This study identified 22 active components in CB, 11 of which were detected in the bloodstream. Preclinical investigations have demonstrated the ability of CB to effectively inhibit liver tumor growth. An integrated approach employing network pharmacology, transcriptomics, and molecular docking implicated the Wnt signaling pathway as a target of the antineoplastic activity of CB by suppressing M2-TAM polarization. In vitro and in vivo experiments further confirmed that CB significantly hinders M2-TAM polarization and suppresses Wnt/ß-catenin pathway activation. The inhibitory effect of CB on M2-TAMs was reversed when treated with the Wnt agonist SKL2001, confirming its pathway specificity. CONCLUSION: This study demonstrated that CB mediates inhibition of M2-TAM polarization through the Wnt/ß-catenin pathway, contributing to the suppression of liver cancer growth.


Assuntos
Neoplasias Hepáticas , Camundongos Nus , Simulação de Acoplamento Molecular , Microambiente Tumoral , Macrófagos Associados a Tumor , Via de Sinalização Wnt , Via de Sinalização Wnt/efeitos dos fármacos , Animais , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Humanos , Camundongos , Células Hep G2 , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/efeitos dos fármacos , Macrófagos Associados a Tumor/imunologia , Microambiente Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Masculino , Farmacologia em Rede , beta Catenina/metabolismo , Medicina Tradicional Chinesa/métodos
15.
Chem Sci ; 15(29): 11367-11373, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39055011

RESUMO

Exploration of pressure-resistant materials largely facilitates their operation under extreme conditions where a stable structure and properties are highly desirable. However, under extreme conditions, such as a high pressure over 30.0 GPa, fluorescence quenching generally occurs in most materials. Herein, pressure-induced emission enhancement (PIEE) by a factor of 4.2 is found in Ga2O3 nanocrystals (NCs), a fourth-generation ultrawide bandgap semiconductor. This is mainly attributed to pressure optimizing the intrinsic lattice defects of the Ga2O3 nanocrystals, which was further confirmed by first-principles calculations. Note that the bright blue emission could be stabilized even up to a high pressure of 30.6 GPa, which is of great significance in the essential components of white light. Notably, after releasing the pressure to ambient conditions, the emission of the Ga2O3 nanocrystals can completely recover, even after undergoing multiple repeated pressurizations. In addition to stable optical properties, synchrotron radiation shows that the Ga2O3 nanocrystals remain in the cubic structure described by space group Fd3m upon compression, demonstrating the structural stability of the Ga2O3 nanocrystals under high pressure. This study pays the way for the application of oxide nanomaterials in pressure anti-counterfeiting and pressure information memory devices.

16.
Front Cell Dev Biol ; 12: 1430386, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39055653

RESUMO

The molecular mechanisms driving the onset and metastasis of prostate cancer remain poorly understood. Actin, under the control of actin-binding proteins (ABPs), plays a crucial role in shaping the cellular cytoskeleton, which in turn supports the morphological alterations in normal cells, as well as the invasive spread of tumor cells. Previous research indicates that ABPs of various types serve distinct functions, and any disruptions in their activities could predispose individuals to prostate cancer. These ABPs are intricately implicated in the initiation and advancement of prostate cancer through a complex array of intracellular processes, such as severing, linking, nucleating, inducing branching, assembling, facilitating actin filament elongation, terminating elongation, and promoting actin molecule aggregation. As such, this review synthesizes existing literature on several ABPs linked to prostate cancer, including cofilin, filamin A, and fascin, with the aim of shedding light on the molecular mechanisms through which ABPs influence prostate cancer development and identifying potential therapeutic targets. Ultimately, this comprehensive examination seeks to contribute to the understanding and management of prostate diseases.

17.
Int J Food Microbiol ; 422: 110814, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-38972103

RESUMO

Ohmic heating (OH), an emerging food processing technology employed in the food processing industry, raises potential food safety concerns due to the recovery of sublethally injured pathogens such as Staphylococcus aureus (S. aureus). In the present study, sensitivity to various stress conditions and the changes in cellular-related factors of OH-injured S. aureus during repair were investigated. The results indicated that liquid media differences (nutrient broth (NB), phosphate-buffered saline (PBS), milk, and cucumber juice) affected the recovery process of injured cells. Nutrient enrichment determines the bacterial repair rate, and the rates of repair for these media were milk > NB > cucumber juice > PBS. The sensitivity of injured cells to various stressors, including different acids, temperature, nisin, simulated gastric fluid, and bile salt, increased during the injury phase and subsequently diminished upon repair. Additionally, the intracellular ATP content, enzyme activities (Na+/K+-ATPase, Ca2+/Mg2+-ATPase, and T-ATPase) and ion concentrations (Mg2+, K+, and Ca2+) gradually increased during repair. After 5 h of repair, the intracellular substances content of cell's was significantly higher than that of the injured bacteria without repair, while some indicators (e.g., Na+/K+-ATPase, K+, and Ca2+) were not restored to the untreated level. The results of this study indicated that OH-injured S. aureus exhibited strengthened resistance post-recovery, potentially due to the restoration of cellular structures. These findings have implications for optimizing food storage conditions and advancing OH processes in the food industry.


Assuntos
Manipulação de Alimentos , Temperatura Alta , Staphylococcus aureus , Manipulação de Alimentos/métodos , Microbiologia de Alimentos , Estresse Fisiológico , Trifosfato de Adenosina/metabolismo
18.
Food Chem ; 459: 140314, 2024 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-39024881

RESUMO

The combined impact of initial state, pressure, and freezing on peroxidase denaturation during high-pressure freezing (HPF) processing of enzyme-containing foods remains unclear. This study investigated solid-liquid (initial low/high concentration) biphasic peroxidase using spectroscopic and computer simulation techniques to analyze structural changes affecting peroxidase (POD) activity under HPF. The results indicate that the primary factors determining POD activity during HPF treatment can be ranked as follows: concentration > physical state > pressure > freezing. Higher initial concentrations strengthen protein interactions, leading to a 1% increase in the molecular diameter and a 34% increase in molecular height of HL-POD, thereby increasing aggregation likelihood during crystallization and facilitating structural changes that activate enzymes by 6-17%. The amide I peak proves to be a reliable indicator for monitoring both POD activity and structural alterations. This study offers valuable insights for optimizing HPF technology in food processing.


Assuntos
Congelamento , Peroxidase , Pressão , Peroxidase/química , Peroxidase/metabolismo , Manipulação de Alimentos , Estabilidade Enzimática
19.
Adv Sci (Weinh) ; 11(34): e2403813, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38981017

RESUMO

The strong ligand effect in B-doped Pd-based (PdB) catalysts renders them a promising anode for constructing formic acid fuel cells (FAFCs) exhibiting high power density and outstanding stability. However, the enhancement of the oxidation barrier is unavoidable in this alloy system owing to the electron transfer (ET) from B to Pd. In this study, a hydrogen doping strategy is employed to open charge freedom in PdB compounds and boost their formic acid oxidation reaction (FAOR) activity by suppressing the ET process. The resulting hydrogen-doped PdB (PdBH) exhibits an ultrahigh mass activity of up to 1.2A mg-1 Pd, which is 3.23 times that of the PdB catalyst and 9.55 times that of Pd black. Detailed experimental and theoretical studies show that the interstitial hydrogen leads to enhanced orbital hybridization and reduced electron density around Pd. This optimized ligand effect weakens the carbon monoxide adsorption and increases the direct pathway preference of PdBH, resulting in its outstanding catalytic activity for the FAOR. The development of this high-performance hydrogen-doped PdB catalyst is an important step toward the construction of advanced light element co-doped metal catalysts.

20.
Nano Lett ; 24(32): 9898-9905, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39007697

RESUMO

The technology of combining multiple emission centers to exploit white-light-emitting (WLE) materials by taking advantage of porous metal-organic frameworks (MOFs) is mature, but preparing undoped WLE MOFs remains a challenge. Herein, a pressure-treated strategy is reported to achieve efficient white photoluminescence (PL) in undoped [Zn(Tdc)(py)]n nanocrystals (NCs) at ambient conditions, where the Commission International del'Eclairage coordinates and color temperature reach (0.31, 0.37) and 6560 K, respectively. The initial [Zn(Tdc)(py)]n NCs exhibit weak-blue PL consisting of localized excited (LE) and planarized intramolecular charge transfer (PLICT) states. After pressure treatment, the emission contributions of LE and PLICT states are balanced by increasing the planarization of subunits, thereby producing white PL. Meanwhile, the reduction of nonradiative decay triggered by the planarized structure results in 5-fold PL enhancement. Phosphor-converted light-emitting diodes based on pressure-treated samples show favorable white-light characteristics. The finding provides a new platform for the development of undoped WLE MOFs.

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