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1.
J Environ Manage ; 360: 121216, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38781877

RESUMEN

The joint participation of multiple subjects is crucial for environmental governance. Using panel data for 273 Chinese cities during 2013-2019, this study investigates the impact and mechanism of public demands on environmental pollution. The results demonstrate that public demands measured by the number of environmental complaints placed on government leaders significantly reduce environmental pollution. Furthermore, increases in the rate and speed of government responses improve the effect of public demands on environmental governance. Public demands placed on provincial leaders reduce local environmental pollution to a greater extent than public demands placed on prefectural and county leaders. Province-level governments are more willing to consider public opinions and attach more importance to environmental governance; Prefecture-level governments prioritize province-level governments' attention to the environment when implementing environmental governance. Moreover, strong political ties between provincial and prefectural leaders and long tenures among prefectural leaders strengthen the pollution reduction effect of public demands placed on provincial leaders. The reduction effect of environmental complaints on pollution emission is more significant in cities with high level of Internet construction and environmental disclosure. Our results illustrate the role of public demands in environmental governance, offering a reference for developing effective environmental policies.


Asunto(s)
Política Ambiental , Contaminación Ambiental , China , Humanos , Gobierno Local , Opinión Pública , Conservación de los Recursos Naturales , Gobierno , Ciudades
2.
Heliyon ; 9(12): e22708, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38089996

RESUMEN

The transition of households towards cleaner energy is crucial for achieving sustainable development goals. However, the impacts and associated mechanisms of early-life experiences on household energy transition have not been considered. Based on data from the 2015 Chinese General Social Survey, this study aimed to investigate whether people experiencing China's Great Famine (1959-1961) in their early life promoted household energy transition in adulthood. The varying severity of the Great Famine in different provinces was characterised as a quasi-natural experiment and was used to perform difference-in-differences (DID) estimation analysis for birth cohorts. The results showed that the transitions from firewood, agricultural waste, and animal waste to liquefied petroleum gas and electricity were significant in households with the Great Famine experiences. Specifically, the long-term energy transition effect of the famine was exhibited mostly in those who experienced the famine during childhood (4-11 years old) and adolescence (12-17 years old). Besides, early-life famine experiences led to poor physical health, and more modern forms of energy, such as electricity, were consumed to avoid further deteriorating health. Early-life famine experience also brought psychological trauma to people at that time, which led them to increase Internet use to gain emotional support, and the increased Internet use provided better access to information about the energy transition. Moreover, the household energy transition influenced by early-life famine experience occurred more in female-headed, rural, more educated, and low-income households. Our results illustrated the role of early-life famine experience in household energy transition and provided new insights into developing effective energy policies.

3.
J Biomol Struct Dyn ; : 1-24, 2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37902557

RESUMEN

Intervertebral disc degeneration (IDD) is a progressive and chronic disease, the mechanisms have been studied extensively as a whole, while the cellular heterogeneity of cells in nucleus pulposus (NP) tissues remained controversial for a long time. This study conducted integrated analysis through single-cell sequencing analysis, weighted gene co-expression network analysis (WGCNA), and differential expression analysis, to systematically decipher the longitudinal alterations of distinct NP subtypes, and also analyzed the most essential genes in the development of IDD. Then, this study further conducted structural biology method to discover the potential lead compounds through a suite of advanced approaches like high-throughput screening (HTVS), pharmaceutical characteristics assessment, CDOCKER module as well as molecular dynamics simulation, etc., aiming to ameliorate the progression of IDD. Totally 5 NP subpopulations were identified with distinct biological functions based on their unique gene expression patterns. The predominant dynamics changes mainly involved RegNPs and EffNPs, the RegNPs were mainly aggregated in normal NP tissues and drastically decreased in degenerative NP, while EffNPs, as pathogenic subtype, exhibited opposite phenomenon. Importantly, this study further reported the essential roles of Menaquinone in alleviating degenerative NP cells for the first time, which could provide solid evidence for the application of nutritional therapy in the treatment of IDD. This study combined scRNA-seq, bulk-RNA seq and HTVS techniques to systematically decipher the longitudinal changes of NP subtypes during IDD. EffNPs were considered to be 'chief culprit' in IDD progression, while the novel natural drug Menaquinone could reverse this phenomenon.Communicated by Ramaswamy H. Sarma.

4.
Phytochemistry ; 215: 113868, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37734513

RESUMEN

Ten previously undescribed meroterpenoids, cyclohexenoneterpenes A-J (1-7, 18-20), together with 10 known analogues (8-17) were isolated from the mangrove-associated fungus Penicillium sp. N-5. Their structures were elucidated on the basis of extensive spectroscopic and mass spectrometric data. The absolute configurations of the undescribed compounds were assigned by electronic circular dichroism calculations, the modified Mosher's method, NMR calculations and DP4+ analysis. In the bioassay, compounds 10, 11, 15, and 20 exhibited cytotoxicities against SNB-19, MDA-MB-231, MDA-MB-435 and HCT-116 cell lines with IC50 values ranging from 1.4 to 19.1 µM.


Asunto(s)
Penicillium , Penicillium/química , Espectroscopía de Resonancia Magnética , Dicroismo Circular , Espectrometría de Masas , Hongos , Estructura Molecular
5.
Langmuir ; 39(18): 6548-6555, 2023 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-37093638

RESUMEN

During the cell viability detection process inside a microfluidic chip, the more uniform the distribution of medium flow rates, the higher the accuracy of detection results. In order to achieve this goal, a multichannel microfluidic chip with uniform distribution of medium flow rates has been successfully designed. The multichannel microfluidic chip is designed with cell injection channels, vascular network-shaped medium injection channels, buffer zones, and a culture chamber. The medium flow rates inside culture chambers of the multichannel microfluidic chip and the common single-channel microfluidic chip are compared by COMSOL Multiphysics software and particle velocimetry experiment. The simulation and experimental results show that the medium flow rate distribution inside the culture chamber of the multichannel microfluidic chip is more uniform and changes more smoothly. When the medium perfusion flow rate is 0.5 µL/min, the maximum flow rate difference inside the culture chamber of the single-channel microfluidic chip is more than 13 times that of the multichannel microfluidic chip. Therefore, the multichannel microfluidic chip can ensure a uniform supply of medium inside the culture chamber, which is beneficial to improve the accuracy of cell viability detection.


Asunto(s)
Técnicas Analíticas Microfluídicas , Microfluídica , Técnicas Analíticas Microfluídicas/métodos , Simulación por Computador , Supervivencia Celular
6.
Molecules ; 27(21)2022 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-36364220

RESUMEN

Protein-surfactant interactions have a significant influence on food functionality, which has attracted increasing attention. Herein, the effect of glycolipid mannosylerythritol lipid-A (MEL-A) on the heat-induced soy glycinin (11S) aggregates was investigated by measuring the structure, binding properties, interfacial behaviors, and emulsification characteristics of the aggregates. The results showed that MEL-A led to a decrease in the surface tension, viscoelasticity, and foaming ability of the 11S aggregates. In addition, MEL-A with a concentration above critical micelle concentration (CMC) reduced the random aggregation of 11S protein after heat treatment, thus facilitating the formation of self-assembling core-shell particles composed of a core of 11S aggregates covered by MEL-A shells. Infrared spectroscopy, circular dichroism spectroscopy, fluorescence spectroscopy, and isothermal titration calorimetry also confirmed that the interaction forces between MEL-A and 11S were driven by hydrophobic interactions between the exposed hydrophobic groups of the protein and the fatty acid chains or acetyl groups of MEL-A, as well as the hydrogen bonding between mannosyl-D-erythritol groups of MEL-A and amino acids of 11S. The findings of this study indicated that such molecular interactions are responsible for the change in surface behavior and the enhancement of foaming stability and emulsifying property of 11S aggregates upon heat treatment.


Asunto(s)
Globulinas , Calor , Globulinas/química , Glucolípidos/química , Lípido A
7.
Food Chem ; 369: 131011, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34507086

RESUMEN

Biosurfactants have been put into applications in breadmaking industry, while the effects of mannosylerythritol lipid-A (MEL-A) on gluten network of frozen dough, bread quality and microbial spoilage were firstly investigated in this study. Rheology and differential scanning calorimetry (DSC) analysis showed that MEL-A significantly improved the rheological properties of frozen dough and reduced the content of frozen water. Further experiments showed that MEL-A promoted the formation of aggregates by interacting with gluten protein, and strengthened the gluten network through molecular weight distribution measurement and microstructure observation, effectively avoiding the destruction of ice crystals. A series of bread assessments illustrated MEL-A improved the loaf volume, gas retention ability and textural property. In addition, MEL-A (1.5%) killed 99.97% of the vegetative cells of Bacillus cereus and 75.54% of the spores, and at the same time had a slight inactivation effect on yeast. These results indicate that MEL-A has broad application prospects in the baking industry and the storage stage of flour products.


Asunto(s)
Pan , Lípido A , Harina , Glútenes , Glucolípidos , Reología , Esporas , Agua
8.
J Fungi (Basel) ; 7(9)2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34575757

RESUMEN

Endophytic fungi infect plant tissues by evading the immune response, potentially stimulating stress-tolerant plant growth. The plant selectively allows microbial colonization to carve endophyte structures through phenotypic genes and metabolic signals. Correspondingly, fungi develop various adaptations through symbiotic signal transduction to thrive in mycorrhiza. Over the past decade, the regulatory mechanism of plant-endophyte interaction has been uncovered. Currently, great progress has been made on plant endosphere, especially in endophytic fungi. Here, we systematically summarize the current understanding of endophytic fungi colonization, molecular recognition signal pathways, and immune evasion mechanisms to clarify the transboundary communication that allows endophytic fungi colonization and homeostatic phytobiome. In this work, we focus on immune signaling and recognition mechanisms, summarizing current research progress in plant-endophyte communication that converge to improve our understanding of endophytic fungi.

9.
Front Microbiol ; 12: 686541, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34394030

RESUMEN

Probiotics have been reported to play a major role in maintaining the balance of microbiota in host. Consumption of food with probiotics has increased with consumer concerns regarding healthy diets and wellness. Correspondingly, safety evaluation of probiotics for human consumption has become increasingly important in food industry. Herein, we aimed to test the safety of Bifidobacterium lactis BL-99 and Lacticaseibacillus paracasei K56 and ET-22 strains in vitro and in vivo. In results, these strains were found to be negative for mucin degradation and platelet aggregation test. Additionally, the three strains were susceptible to eight antibiotics. In accordance with bacterial reversion mutation (Ames) assay, the tested strains had no genetic mutagenicity. Finally, it was confirmed that there were no dose-dependent mortality and toxicity throughout multidose oral toxicity tests in rats. Our findings demonstrated that B. lactis BL-99 and L. paracasei K56 and ET-22 can achieve the generally recognized as safe (GRAS) status as probiotics in the future.

10.
Molecules ; 26(15)2021 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-34361675

RESUMEN

Flavonoids belong to a class of plant secondary metabolites that have a polyphenol structure. Flavonoids show extensive biological activity, such as antioxidative, anti-inflammatory, anti-mutagenic, anti-cancer, and antibacterial properties, so they are widely used in the food, pharmaceutical, and nutraceutical industries. However, traditional sources of flavonoids are no longer sufficient to meet current demands. In recent years, with the clarification of the biosynthetic pathway of flavonoids and the development of synthetic biology, it has become possible to use synthetic metabolic engineering methods with microorganisms as hosts to produce flavonoids. This article mainly reviews the biosynthetic pathways of flavonoids and the development of microbial expression systems for the production of flavonoids in order to provide a useful reference for further research on synthetic metabolic engineering of flavonoids. Meanwhile, the application of co-culture systems in the biosynthesis of flavonoids is emphasized in this review.


Asunto(s)
Reactores Biológicos/microbiología , Escherichia coli/metabolismo , Flavonoides/biosíntesis , Ingeniería Metabólica/métodos , Saccharomyces cerevisiae/metabolismo , Técnicas de Cocultivo/métodos , Escherichia coli/genética , Fermentación , Flavonoides/química , Flavonoides/clasificación , Estructura Molecular , Plantas/metabolismo , Saccharomyces cerevisiae/genética , Metabolismo Secundario , Biología Sintética/métodos
11.
J Fungi (Basel) ; 7(4)2021 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-33807450

RESUMEN

To evaluate the novel strategy of oleic acid and fungal elicitor (made from Aspergillus niger) to elicit betulinic acid biosynthesis in medicinal mushroom Inonotus obliquus, we conduct the stimulatory effects investigation for synthesizing betulinic acid from betulin. HPLC results indicated oleic acid and fungal elicitor were effective stimulators. The supplementation of 1.0 g/L oleic acid led to the highest increase of betulinic acid either in dry mycelia or fermentation broth by 2-fold of the control. Fungal elicitor at 45 mg/L markedly increases mycelia growth by 146.0% and enhance intracellular betulinic acid accumulation by 429.5% as compared to the controls. Quantification of transcription levels determined that oleic acid, fungal elicitor and their combinations could induce the expressions of key genes involved in betulinic acid biosynthesis, such as HMG-CoA reductase and squalene synthase. These findings indicated that oleic acid and fungal elicitor could enhance betulinic acid metabolism by up-regulating key genes expression.

12.
Pharmaceutics ; 13(2)2021 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-33562052

RESUMEN

Glycolipid biosurfactants are natural amphiphiles and have gained particular interest recently in their biodegradability, diversity, and bioactivity. Microbial infection has caused severe morbidity and mortality and threatened public health security worldwide. Glycolipids have played an important role in combating many diseases as therapeutic agents depending on the self-assembly property, the anticancer and anti-inflammatory properties, and the antimicrobial properties, including antibacterial, antifungal, and antiviral effects. Besides, their role has been highlighted as scavengers in impeding the biofilm formation and rupturing mature biofilm, indicating their utility as suitable anti-adhesive coating agents for medical insertional materials leading to a reduction in vast hospital infections. Notably, glycolipids have been widely applied to the synthesis of novel antimicrobial materials due to their excellent amphipathicity, such as nanoparticles and liposomes. Accordingly, this review will provide various antimicrobial applications of glycolipids as functional ingredients in medical therapy.

13.
Ultrason Sonochem ; 72: 105452, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33388695

RESUMEN

Methicillin-resistant Staphylococcus aureus (MRSA) is drug-resistant and biofilm-forming pathogenic bacteria with severe morbidity and mortality, and has been continuously detected in food products in recent years. Mannosylerythritol lipids (MELs) are novel biosurfactants and perform antibacterial property against gram-positive bacteria. Ultrasound has been applied into food sterilization as non-thermal techniques and has advantage of maintaining food nutrition and flavor over heat pasteurization. In this work, the synergistic treatment of ultrasound and MEL-A was used to combat planktonic cells and biofilm of MRSA. As a result, the combined treatment has exhibited remarkable antibacterial effect proved by enumeration of viable microbes. Furthermore, flow cytometry, scanning electron microscopy and transmission electron microscopy revealed ultrasound has enhanced the inhibitory effect of MEL-A through exacerbating cell membrane damage. On the other hand, the collaborating working modes to eradicate MRSA biofilm were disturbing cell adhesion to surface by MEL-A and destructing mature biofilm mechanically by ultrasound, reaching to over 90% of clearance rate. The findings of this study illustrated the synergistic antimicrobial mechanism of ultrasound and MEL-A treatments, and offered theoretical basis for their potential applications in food preservation.


Asunto(s)
Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Glucolípidos/farmacología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/fisiología , Ondas Ultrasónicas , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Espacio Intracelular/efectos de los fármacos , Espacio Intracelular/metabolismo , Staphylococcus aureus Resistente a Meticilina/citología , Pruebas de Sensibilidad Microbiana
14.
Molecules ; 25(16)2020 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-32781689

RESUMEN

Ethyl carbamate (EC) is a potential carcinogen that forms spontaneously during Chinese rice wine fermentation. The primary precursor for EC formation is urea, which originates from both external sources and arginine degradation. Urea degradation is suppressed by nitrogen catabolite repression (NCR) in Saccharomyces cerevisiae. The regulation of NCR is mediated by two positive regulators (Gln3p, Gat1p/Nil1p) and two negative regulators (Dal80p/Uga43p, Deh1p/Nil2p/GZF3p). DAL80 revealed higher transcriptional level when yeast cells were cultivated under nitrogen-limited conditions. In this study, when DAL80-deleted yeast cells were compared to wild-type BY4741 cells, less urea was accumulated, and genes involved in urea utilization were up-regulated. Furthermore, Chinese rice wine fermentation was conducted using dal80Δ cells; the concentrations of urea and EC were both reduced when compared to the BY4741 and traditional fermentation starter. The findings of this work indicated Dal80p is involved in EC formation possibly through regulating urea metabolism and may be used as the potential target for EC reduction.


Asunto(s)
Factores de Transcripción GATA/deficiencia , Factores de Transcripción GATA/genética , Eliminación de Gen , Proteínas Represoras/deficiencia , Proteínas Represoras/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Uretano/metabolismo , Vino/microbiología , Arginasa/metabolismo , Proliferación Celular/genética , Fermentación/genética , Espacio Intracelular/enzimología , Saccharomyces cerevisiae/citología , Ureasa/metabolismo
15.
Appl Microbiol Biotechnol ; 104(11): 5053-5064, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32248439

RESUMEN

Mannosylerythritol lipids (MELs) are novel biosurfactants performing excellent physical-chemical properties as well as bioactivities. This study is aimed to explore the antibacterial and antibiofilm activity of mannosylerythritol lipids against foodborne gram-positive Staphylococcus aureus. The results of growth curve and survival rate revealed the significant inhibitory effect of MELs against S. aureus. The visualized pictures by scanning electron microscope and transmission electron microscope exposed apparent morphological and ultrastructure changes of MEL-treated cells. Furthermore, flow cytometry confirmed that MELs have promoted cell apoptosis and damaged the cell membrane. Notably, MEL-A also exhibited outstanding antibiofilm activity against S. aureus biofilm on different material surfaces including polystyrene, glass, and stainless steel, verified by confocal laser scanning microscope. These findings suggest that the antimicrobial activity of MELs is related to inhibit planktonic cells and biofilm of S. aureus, indicating that it has potential to be an alternative to antibacterial agents and preservatives applied into food processing.Key Points • MELs have strong antibacterial activity against Staphylococcus aureus.• MELs mainly damage the cell membrane of Staphylococcus aureus.• Mannosylerythritol lipids inhibit the bacterial adhesion to remove biofilm.


Asunto(s)
Antibacterianos/farmacología , Apoptosis/efectos de los fármacos , Membrana Externa Bacteriana/efectos de los fármacos , Biopelículas/efectos de los fármacos , Glucolípidos/farmacología , Staphylococcus aureus/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Microbiología de Alimentos , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos , Tensoactivos/farmacología
16.
Ultrason Sonochem ; 64: 105040, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32120239

RESUMEN

Agaricus bitorquis (Quél.) Sacc. Chaidam (ABSC), is a kind of rare edible macrofungi with a variety of biological ingredients, especially its polysaccharides. However, the low yield limits the popularity and promotion of rare edible macrofungi as well as its macrofungi polysaccharides. Hence, developing a positive and effective cultivation method is of great importance. Herein, an efficient ultrasonic (US) stimulation strategy was developed to improve mycelial growth and exopolysaccharides (EPS) biosynthesis from ABSC in submerged cultivation without light. A time design was employed to illustrate the effect of various process parameters including duration, starting point and times of US irradiation on ABSC productivity. 5 min US treatment for once upon ABSC after fermentation for 48 h could significantly improve EPS production and mycelia growth by above 26% and 15.03%, respectively. Furthermore, six times of 5 min US treatment could make the amount of EPS reach 218.78 ± 17.09 mg/g, which was 2.52-fold higher than that of the control. Moreover, the enhanced effect induced by US was further expounded by fermentation kinetics. Besides, the US treatment could increase mycelia permeability, change structure and reduce mycelial diameter to promote mass transfer, resulting in the improvement of EPS production and mycelia accumulation. The results demonstrated that the present proposed US intensification approach could be useful to boost up the fermentation of ABSC, which possibly applied to yield increase and fermentation product acquisition of macrofungi.


Asunto(s)
Agaricus/metabolismo , Biotecnología/métodos , Polisacáridos Fúngicos/biosíntesis , Micelio/crecimiento & desarrollo , Ondas Ultrasónicas , Agaricus/citología , Ácidos Grasos/metabolismo , Cinética , Permeabilidad
17.
J Hazard Mater ; 175(1-3): 569-74, 2010 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-19913358

RESUMEN

Pentanitromonoformylhexaazaisowurtzitane (PNMFIW) was synthesized by the nitrolysis of tetraacetyldiformylhexaazaisowurtzitane (TADFIW) in mixed nitric and sulfuric acids and structurally characterized by element analysis, FT-IR, MS and (1)H NMR. Single crystals of PNMFIW were grown from aqueous solution employing the technique of controlled evaporation. PNMFIW belongs to the orthorhombic system having four molecules in the unit cell, with space group P2(1)2(1)2(1) and the lattice parameters a=8.8000(18)A, b=12.534(2)A, and c=12.829(3)A. The calculated density reaches 1.977 g/cm(3) at 93 K, while the experimental density is 1.946 g/cm(3) at 20 degrees C. The calculated detonation velocity and pressure of PNMFIW according to the experimental density are 9195.76 m/s and 39.68G Pa, respectively. PNMFIW is insensitive compared with epsilon-HNIW through drop hammer impact sensitivity test.


Asunto(s)
Compuestos Heterocíclicos de 4 o más Anillos/química , Nitrocompuestos/química , Nitrógeno/química , Cristalización , Cristalografía por Rayos X/métodos , Electroquímica/métodos , Compuestos Heterocíclicos de 4 o más Anillos/síntesis química , Espectroscopía de Resonancia Magnética/métodos , Espectrometría de Masas/métodos , Estructura Molecular , Nitrocompuestos/síntesis química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Ácidos Sulfúricos/química , Temperatura
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