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1.
J Am Chem Soc ; 146(13): 9036-9044, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38507821

RESUMO

Two-dimensional conductive metal-organic frameworks (2D c-MOFs), which feature high electrical conductivity and large charge carrier mobility, hold great promise in electronics and optoelectronics. Nevertheless, the limited solubility of commonly used planar ligands inevitably brings challenges in synthesis and purification and causes laborious coordination conditions for screening. Moreover, most reported 2D c-MOFs are polycrystalline powders with relatively low crystallinity and irregular morphology, hindering the unveiling of the detailed structure-function relationship. Herein, we developed a "rotor-stator" molecular design strategy to construct 2D c-MOFs using a delicately designed nonplanar biscarbazole ligand (8OH-DCB). Benefiting from the special "rotor-stator" structure of the ligand, crystals of Cu-DCB-MOF were successfully prepared, allowing for the precise determination of their crystal structure. Interestingly, the crystals of Cu-DCB-MOF can be obtained in various organic solvents, indicating excellent solvent compatibility. The versatility of the "rotor-stator" molecular design strategy was further demonstrated by another two new ligands with a "rotor-stator" structure, and afford corresponding 2D c-MOF crystals (Cu-DCBT-MOF and Cu-DCBBT-MOF). The current work presents a facile approach toward the rational design and direct construction of highly crystalline 2D c-MOFs using nonplanar ligands.

2.
J Am Chem Soc ; 146(15): 10868-10874, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38573037

RESUMO

Liquid water provides the largest hydrogen reservoir on the earth's surface. Direct utilization of water as a source of hydrogen atoms and molecules is fundamental to the evolution of the ecosystem and industry. However, liquid water is an unfavorable electron donor for forming these hydrogen species owing to its redox inertness. We report oil-mediated electron extraction from water microdroplets, which is easily achieved by ultrasonically spraying an oil-water emulsion. Based on charge measurement and electron paramagnetic resonance spectroscopy, contact electrification between oil and a water microdroplet is demonstrated to be the origin of electron extraction from water molecules. This contact electrification results in enhanced charge separation and subsequent mutual neutralization, which enables a ∼13-fold increase of charge carriers in comparison with an ultrapure water spray, leading to a ∼16-fold increase of spray-sourced hydrogen that can hydrogenate CO2 to selectively produce CO. These findings emphasize the potential of charge separation enabled by spraying an emulsion of liquid water and a hydrophobic liquid in driving hydrogenation reactions.

3.
Compr Rev Food Sci Food Saf ; 23(1): e13257, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38284611

RESUMO

Cow milk is a major allergenic food. The potential prevention and treatment effects of lactic acid bacteria (LAB)-fermented dairy products on allergic symptoms have garnered considerable attention. Cow milk allergy (CMA) is mainly attributed to extracellular and/or cell envelope proteolytic enzymes with hydrolysis specificity. Numerous studies have demonstrated that LAB prevents the risk of allergies by modulating the development and regulation of the host immune system. Specifically, LAB and its effectors can enhance intestinal barrier function and affect immune cells by interfering with humoral and cellular immunity. Fermentation hydrolysis of allergenic epitopes is considered the main mechanism of reducing CMA. This article reviews the linear epitopes of allergens in cow milk and the effect of LAB on these allergens and provides insight into the means of predicting allergenic epitopes by conventional laboratory analysis methods combined with molecular simulation. Although LAB can reduce CMA in several ways, the mechanism of action remains partially clarified. Therefore, this review additionally attempts to summarize the main mechanism of LAB fermentation to provide guidance for establishing an effective preventive and treatment method for CMA and serve as a reference for the screening, research, and application of LAB-based intervention.


Assuntos
Produtos Fermentados do Leite , Lactobacillales , Hipersensibilidade a Leite , Animais , Bovinos , Feminino , Alérgenos/análise , Fermentação , Hipersensibilidade a Leite/prevenção & controle , Epitopos
4.
Cell Rep ; 43(3): 113959, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38483903

RESUMO

The extrinsic diet and the intrinsic developmental programs are intertwined. Although extensive research has been conducted on how nutrition regulates development, whether and how developmental programs control the timing of nutritional responses remain barely known. Here, we report that a developmental timing regulator, BLMP-1/BLIMP1, governs the temporal response to dietary restriction (DR). At the end of larval development, BLMP-1 is induced and interacts with DR-activated PHA-4/FOXA, a key transcription factor responding to the reduced nutrition. By integrating temporal and nutritional signaling, the DR response regulates many development-related genes, including gska-3/GSK3ß, through BLMP-1-PHA-4 at the onset of adulthood. Upon DR, a precocious activation of BLMP-1 in early larval stages impairs neuronal development through gska-3, whereas the increase of gska-3 by BLMP-1-PHA-4 at the last larval stage suppresses WNT signaling in adulthood for DR-induced longevity. Our findings reveal a temporal checkpoint of the DR response that protects larval development and promotes adult health.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Restrição Calórica , Regulação da Expressão Gênica , Longevidade/genética , Fatores de Transcrição/metabolismo , Via de Sinalização Wnt
5.
Int J Food Microbiol ; 418: 110743, 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38749262

RESUMO

Spicy cabbage is a popular fermented vegetable food. The study aimed to determine the physicochemical properties, volatile flavor components, sensory evaluation, and microbial diversity of spicy cabbage prepared using different methods. Three methods were used: single-bacteria fermentation with Lactiplantibacillus plantarum YB-106 and Leuconostoc mesenteroides YB-23, mixed fermentation (LMP) using both strains, and natural fermentation as the blank control (CON). The LMP group has the best quality of spicy cabbage and the highest sensory score. Esters and alkenes were the main volatile flavor components of the spicy cabbage by GC-MS. The fermentation time of LMP group was shorter, and the nitrite degradation rate was >60 %, which was significantly higher than that of other groups (p < 0.05). From the perspective of microbial diversity, the dominant bacteria genera in each group were Lactobacillus, Pantoea, Enterococcus and Pseudomonas. However, mixed fermentation decreased the abundance of pathogenic bacteria, of which the abundance of Serratia was <0.1 %. In conclusion, mixed fermentation can significantly improve the quality of spicy cabbage and shorten the fermentation time. These findings laid the theoretical foundation for the industrial production of high-quality spicy cabbage.


Assuntos
Brassica , Fermentação , Alimentos Fermentados , Microbiologia de Alimentos , Leuconostoc mesenteroides , Brassica/microbiologia , Leuconostoc mesenteroides/metabolismo , Alimentos Fermentados/microbiologia , Lactobacillus plantarum/metabolismo , Lactobacillus plantarum/classificação , Paladar , Biodiversidade
6.
Int J Chron Obstruct Pulmon Dis ; 19: 1755-1765, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39099609

RESUMO

Chronic Obstructive Pulmonary Disease (COPD) exerts a severe toll on human health and the economy, with high prevalence and mortality rates. The search for bioactive components effective in the treatment of COPD has become a focal point of research. Beetroot juice, readily accessible and cost-effective, is noted for its ability to enhance athletic performance and for its preventive and therapeutic impact on hypertension. Beetroot juice is a rich source of dietary nitrates and modulates physiological processes via the nitrate-nitrite- nitric oxide pathway, exerting multiple beneficial effects such as antihypertensive, bronchodilatory, anti-inflammatory, antioxidant, hypoglycemic, and lipid-lowering actions. This paper provides a review of the existing research on the effects of beetroot juice on COPD, summarizing its potential in enhancing exercise capacity, lowering blood pressure, improving vascular function, and ameliorating sleep quality among patients with COPD. The review serves as a reference for the prospective use of beetroot juice in the symptomatic improvement of COPD, as well as in the prevention of exacerbations and associated comorbidities.


Assuntos
Beta vulgaris , Tolerância ao Exercício , Sucos de Frutas e Vegetais , Pulmão , Doença Pulmonar Obstrutiva Crônica , Humanos , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/dietoterapia , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Beta vulgaris/química , Pulmão/fisiopatologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Resultado do Tratamento , Tolerância ao Exercício/efeitos dos fármacos , Raízes de Plantas , Nitratos , Sono/efeitos dos fármacos , Recuperação de Função Fisiológica , Animais
7.
Nutrients ; 16(8)2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38674869

RESUMO

The study explored the potential protective impact of the probiotic fungus Eurotium amstelodami in Fuzhuan brick tea on ulcerative colitis, along with the underlying mechanism. A spore suspension of E. amstelodami was administered to C57BL/6 mice to alleviate DSS-induced colitis. The findings indicated that administering E. amstelodami evidently enhanced the ultrastructure of colonic epithelium, showing characteristics such as enhanced TJ length, reduced microvilli damage, and enlarged intercellular space. After HLL supplementation, the activation of the liver inflammation pathway, including TLR4/NF-kB and NLRP3 inflammasome caused by DSS, was significantly suppressed, and bile acid metabolism, linking liver and gut, was enhanced, manifested by restoration of bile acid receptor (FXR, TGR5) level. The dysbiosis of the gut microbes in colitis mice was also restored by HLL intervention, characterized by the enrichment of beneficial bacteria (Lactobacillus, Bifidobacterium, Akkermansia, and Faecalibaculum) and fungi (Aspergillus, Trichoderma, Wallemia, Eurotium, and Cladosporium), which was closely associated with lipid metabolism and amino acid metabolism, and was negatively correlated with inflammatory gene expression. Hence, the recovery of gut microbial community structure, implicated deeply in the inflammatory index and metabolites profile, might play a crucial role in the therapeutic mechanism of HLL on colitis.


Assuntos
Sulfato de Dextrana , Eurotium , Microbioma Gastrointestinal , Camundongos Endogâmicos C57BL , Chá , Animais , Microbioma Gastrointestinal/efeitos dos fármacos , Camundongos , Chá/química , Masculino , Probióticos/farmacologia , Colite/induzido quimicamente , Disbiose , Colo/efeitos dos fármacos , Colo/metabolismo , Colo/patologia , Fígado/metabolismo , Fígado/efeitos dos fármacos , Fígado/patologia , Modelos Animais de Doenças , Colite Ulcerativa/induzido quimicamente , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo
8.
J Agric Food Chem ; 72(27): 15198-15212, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38941263

RESUMO

Numerous studies have highlighted the potential of Lactic acid bacteria (LAB) fermentation of whey proteins for alleviating allergies. Nonetheless, the impact of LAB-derived metabolites on whey proteins antigenicity during fermentation remains uncertain. Our objective was to elucidate the impact of small molecular metabolites on the antigenicity of α-lactalbumin (α-LA) and ß-lactoglobulin (ß-LG). Through metabolomic analysis, we picked 13 bioactive small molecule metabolites from Lactobacillus delbrueckii subsp. bulgaricus DLPU F-36 for coincubation with α-LA and ß-LG, respectively. The outcomes revealed that valine, arginine, benzoic acid, 2-keto butyric acid, and glutaric acid significantly diminished the sensitization potential of α-LA and ß-LG, respectively. Moreover, chromatographic analyses unveiled the varying influence of small molecular metabolites on the structure of α-LA and ß-LG, respectively. Notably, molecular docking underscored that the primary active sites of α-LA and ß-LG involved in protein binding to IgE antibodies aligned with the interaction sites of small molecular metabolites. In essence, LAB-produced metabolites wield a substantial influence on the antigenic properties of whey proteins.


Assuntos
Lactobacillus delbrueckii , Simulação de Acoplamento Molecular , Proteínas do Soro do Leite , Lactobacillus delbrueckii/metabolismo , Lactobacillus delbrueckii/química , Lactobacillus delbrueckii/imunologia , Proteínas do Soro do Leite/química , Proteínas do Soro do Leite/metabolismo , Fermentação , Lactoglobulinas/química , Lactoglobulinas/imunologia , Lactoglobulinas/metabolismo , Lactalbumina/química , Lactalbumina/imunologia , Lactalbumina/metabolismo , Animais , Bovinos , Antígenos/imunologia , Antígenos/química
9.
J Food Sci ; 89(7): 4505-4521, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38778560

RESUMO

Cow milk allergy is one of the common food allergies. Our previous study showed that the allergenicity of fermented milk is lower than that of unfermented skimmed milk in vitro, and the antigenicity of ß-lactoglobulin and α-lactalbumin in fermented milk was decreased by 67.54% and 80.49%, respectively. To confirm its effects in vivo, allergic BALB/C mice model was used to further study the allergenicity of fermented milk. It was found that compared with the skim milk (SM) group, the intragastrically sensitization with fermented milk had no obvious allergic symptoms and the fingers were more stable: lower levels of IgE, IgG, and IgA in serum, lower levels of plasma histamine and mast cell protein-1, and immune balance of Th1/Th2 and Treg/Th17. At the same time, intragastrically sensitization with fermented milk increased the α diversity of intestinal microbiota and changed the microbiota abundance: the relative abundance of norank-f-Muribaculaceae and Staphylococcus significantly decreased, and the abundance of Lachnospiraceae NK4A136 group, Bacteroides, and Turicibacter increased. In addition, fermented milk can also increase the level of short-chain fatty acids in the intestines of mice. It turns out that fermented milk is much less allergenicity than SM. PRACTICAL APPLICATION: Fermentation provides a theoretical foundation for reducing the allergenicity of milk and dairy products, thereby facilitating the production of low-allergenic dairy products suitable for individuals with milk allergies.


Assuntos
Fermentação , Microbioma Gastrointestinal , Imunoglobulina E , Lactobacillales , Camundongos Endogâmicos BALB C , Hipersensibilidade a Leite , Leite , Animais , Hipersensibilidade a Leite/imunologia , Camundongos , Imunoglobulina E/imunologia , Imunoglobulina E/sangue , Leite/imunologia , Feminino , Lactobacillales/imunologia , Bovinos , Produtos Fermentados do Leite/microbiologia , Lactoglobulinas/imunologia , Imunoglobulina A , Lactalbumina/imunologia , Imunoglobulina G/sangue , Ácidos Graxos Voláteis/metabolismo , Histamina/metabolismo
10.
J Food Sci ; 89(7): 4109-4122, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38957103

RESUMO

The elucidation of the interaction mechanism between phospholipids and milk proteins within emulsions is pivotal for comprehending the properties of infant formula fat globules. In this study, multispectral methods and molecular docking were employed to explore the relationship between phosphatidylcholine (PC) and whey protein isolate (WPI). Observations indicate that the binding constant, alongside thermodynamic parameters, diminishes as temperature ascends, hinting at a predominantly static quenching mechanism. Predominantly, van der Waals forces and hydrogen bonds constitute the core interactions between WPI and PC. This assertion is further substantiated by Fourier transform infrared spectroscopy, which verifies PC's influence on WPI's secondary structure. A detailed assessment of thermodynamic parameters coupled with molecular docking reveals that PC predominantly adheres to specific sites within α-lactalbumin, ß-lactoglobulin, and bovine serum albumin, propelled by a synergy of hydrophobic interactions, hydrogen bonding, and van der Waals forces, with binding energies noted at -5.59, -6.71, and -7.85 kcal/mol, respectively. An increment in PC concentration is observed to amplify the emulsification properties of WPI whilst concurrently diminishing the zeta potential. This study establishes a theoretical foundation for applying the PC-WPI interaction mechanism in food.


Assuntos
Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Simulação de Acoplamento Molecular , Fosfatidilcolinas , Termodinâmica , Proteínas do Soro do Leite , Proteínas do Soro do Leite/química , Fosfatidilcolinas/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Lactoglobulinas/química , Lactoglobulinas/metabolismo , Emulsões/química , Lactalbumina/química , Lactalbumina/metabolismo , Soroalbumina Bovina/química , Fórmulas Infantis/química
11.
Food Chem ; 460(Pt 2): 140634, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39079355

RESUMO

This study used ultra-high pressure processing (HPP) heat-assisted technology combined with L-cysteine (L-cys) to process ready-to-eat (RTE) shrimp. Subsequently, the effects of physical field and chemical modifications on the color of RTE shrimp were studied. The results showed that the RTE shrimp treated with HPP-Heat-L-cys showed better performance in terms of brightness value (65.25) and astaxanthin (AST) content (0.71 µg/g) during storage, maintaining the original color of RTE shrimp effectively. In addition, it was observed that the application of HPP-Heat-L-cys significantly delayed phenol oxidation, lipid oxidation, and Maillard reaction compared with traditional HPP or heat treatments. Specifically, the total phenolic content of RTE shrimp treated with HPP-Heat-L-cys was higher than that of other samples, but the TBARS and browning index were lower. Furthermore, HPP-Heat-L-cys could delay the production of dark products (such as 2-methylanthraquinone, p-benzoquinone, lipofuscin and melanin), ultimately safeguarding the color stability of RTE shrimp during storage.

12.
Food Chem X ; 20: 100911, 2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38144817

RESUMO

Milk allergy is one of the most common food allergies, in which αS-casein is the major milk allergen. Under optimized conditions, mixed starter (containing Lactobacillus plantarum 7-2 and commercial starter) effectively degraded αS-casein of skimmed milk and reduced the pressure of stomach digestion. The fermented milk prepared by mixed starter was determined by ELISA, the antigenicity of αS-casein was reduced by 77.53%. Compared with the fermented milk prepared by commercial starter, label-free quantitative proteomics demonstrated that the mixed starter more efficiently degraded the epitopes of major milk allergens and influenced the digestion pattern of the fermented milk. Therefore, L. plantarum 7-2 shows positive potential in reducing the antigenicity of αS-casein and others. In addition, this study predicted that the new epitopes produced in the fermentation process could induce immunity using molecular simulation.

13.
Heliyon ; 9(12): e22852, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38125520

RESUMO

Science popularization is not only a prerequisite for national development, but also an effective means of enhancing citizens' personal quality. All sectors of society, represented by colleges and universities, bear the responsibility of promoting popular science. The integration of popular science and tourism in popular science tourism serves to advance both the field of popular science and the tourism industry simultaneously. The Guangzhou Higher Education Mega Center (HEMC) possesses abundant resources for science popularization and has the potential to develop popular science tourism, yet its current development in this area remains insufficient. This study utilizes Guangzhou HEMC as a case study and modifies the American Customer Satisfaction Index model by incorporating relevant questions pertaining to popular science tourism. A total of 280 valid questionnaires were collected through surveying, which were then analyzed to measure tourist satisfaction using the Tourist Satisfaction Index. The partial least squares structural equation model was employed for analysis, and on the basis of calculation results, the IPA map was constructed. The research revealed that tourists' satisfaction with popular science tourism at Guangzhou HEMC was suboptimal. Among the factors correlating to satisfaction, expectations, quality, and price are all important factors to consider when making a purchase decision; however, prioritizing expectations and quality can lead to greater satisfaction in the long run. Therefore, there is still ample room for improvement in the popular science tourism of HEMC Guangzhou. This can be achieved by intensifying publicity efforts, enhancing infrastructure, improving the quality and safety of catering services, strengthening the introduction and construction of popular science content, as well as appropriately reducing the price of popular science products and services.

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