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1.
ACS Appl Mater Interfaces ; 16(15): 19730-19741, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38591140

RESUMEN

Metal-organic framework materials can be converted into carbon-based nanoporous materials by pyrolysis, which have a wide range of applications in energy storage. Here, we design special interface engineering to combine the carbon skeleton and nitrogen-doped carbon nanotubes (CNTs) with the transition metal compounds (TMCs) well, which mitigates the bulk effect of the TMCs and improves the conductivity of the electrodes. Zeolitic imidazolate framework-67 is used as a precursor to form a carbon skeleton and a large number of nitrogen-doped CNTs by pyrolysis followed by the in situ formation of Co3O4 and CoS2, and finally, Co3O4@CNTs and CoS2@CNTs are synthesized. The obtained anode electrodes exhibit a long cycle life and high-rate properties. In lithium-ion batteries (LIBs), Co3O4@CNTs have a high capacity of 581 mAh g-1 at a high current of 5 A g-1, and their reversible capacity is still 1037.6 mAh g-1 after 200 cycles at 1 A g-1. In sodium-ion batteries (SIBs), CoS2@CNTs have a capacity of 859.9 mAh g-1 at 0.1 A g-1 and can be retained at 801.2 mAh g-1 after 50 cycles. The unique interface engineering and excellent electrochemical properties make them ideal anode materials for high-rate, long-life LIBs and SIBs.

2.
Small ; 20(1): e2305322, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37641186

RESUMEN

Solid-state batteries have become the most anticipated option for compatibility with high-energy density and safety. In situ polymerization, a novel strategy for the construction of solid-state systems, has extended its application from solid polymer electrolyte systems to other solid-state systems. This review summarizes the application of in situ polymerization strategies in solid-state batteries, which covers the construction of polymer, the formation of the electrolyte system, and the design of the full cell. For the polymer skeleton, multiple components and structures are being chosen. In the construction of solid polymer electrolyte systems, the choice of initiator for in situ polymerization is the focus of this review. New initiators, represented by lithium salts and additives, are the preferred choice because of their ability to play more diverse roles, while the coordination with other components can also improve the electrical properties of the system and introduce functionalities. In the construction of entire solid-state battery systems, the application of in situ polymerization to structure construction, interface construction, and the use of separators with multiplex functions has brought more possibilities for the development of various solid-state systems and even the perpetuation of liquid electrolytes.

3.
J Agric Food Chem ; 71(51): 20713-20723, 2023 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-38095326

RESUMEN

Two new terrein derivatives, aspergilethers A and B (1 and 2), two known analogues (3 and 4), and three known butenolides (5-7) were isolated from the endophyte Aspergillus terreus HT5. Their structures were determined by spectroscopic analysis and ECD and NMR calculations. Interestingly, 1 and 2 had unpresented medium aliphatic side chains in terrein derivatives, with different absolute configurations at C-7, which was very scarce. (+)-Terrein (3) exhibited potent postemergence phytotoxicity toward Amaranthaceae, Portulacaceae, and Fabaceae, with MIC values of 250-1000 µg/mL. Transcriptome analysis and qRT-PCR suggested that (+)-terrein induced the transcriptional expression of aging-related genes to accelerate organ senescence and stimulated plant detoxification response. The conjugated system between keto carbonyl and double bonds in the cyclopentenone ring and side chain, and the configurations of C-2 and C-3, played critical roles in the phytotoxicity of terrein derivatives. Meanwhile, 3 was first reported to display moderate antioomycetes activity toward Phytophthora nicotiana.


Asunto(s)
Antiinfecciosos , Toxinas Biológicas , Aspergillus/metabolismo , Antiinfecciosos/metabolismo , Toxinas Biológicas/metabolismo , Estructura Molecular
4.
Ecotoxicol Environ Saf ; 247: 114273, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36356529

RESUMEN

Sterigmatocystin (STE) is a common hepatotoxic and nephrotoxic contaminant in cereals, however, its phytotoxicity and mechanisms are poorly understood. Here, the phytotoxic mechanisms of STE were investigated via the metabolomics of Amaranthus retroflexus L. A total of 140 and 113 differential metabolites were detected in the leaves and stems, respectively, among which amino acids, lipids, and phenolic compounds were significantly perturbed. Valine, leucine, isoleucine, and lysine biosynthesis were affected by STE. These metabolic responses revealed that STE might be toxic to plants by altering the plasma membrane and inducing oxidative damage, which was verified by measuring the relative electrical conductivity and quantification of reactive oxygen species. The elevated amino acids, as well as the decreased of D-sedoheptuiose-7-phosphate indicated increased proteolysis and carbohydrate metabolism restriction. Furthermore, the IAA level also decreased. This study provides a better understanding of the impacts of STE on the public health, environment and food security.


Asunto(s)
Alcaloides , Amaranthus , Toxinas Biológicas , Esterigmatocistina , Metabolómica , Aminoácidos
5.
Microbiol Spectr ; 10(4): e0154222, 2022 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-35943267

RESUMEN

Phytophthora nicotianae is an oomycete pathogen of global significance threatening many important crops. It is mainly controlled by chemosynthetic fungicides, which endangers ecosystem and human health; thus, there is an urgent need to explore alternatives for these fungicides. In this study, a new anti-oomycete aliphatic compound, 2E,4E-decadienoic acid (DDA), was obtained through coculture of Bacillus subtilis Tpb55 and Trichoderma asperellum HG1. Both in vitro and in vivo tests showed that DDA had a strong inhibitory effect against P. nicotianae. In addition, rhizosphere microbiome analysis showed that DDA reduced the relative abundance of Oomycota in rhizosphere soil. Transcriptome sequencing (RNA-Seq) analysis revealed that treatment of P. nicotianae with DDA resulted in significant downregulation of antioxidant activity and energy metabolism, including antioxidant enzymes and ATP generation, and upregulation of membrane-destabilizing activity, such as phospholipid synthesis and degradation. The metabolomic analysis results implied that the pathways influenced by DDA were mainly related to carbohydrate metabolism, energy metabolism, and the cell membrane. The biophysical tests further indicated that DDA produced oxidative stress on P. nicotianae, inhibited antioxidant enzyme and ATPase activity, and increased cell membrane permeability. Overall, DDA exerts inhibitory activity by acting on multiple targets in P. nicotianae, especially on the cell membrane and mitochondria, and can therefore serve as a novel environment-friendly agent for controlling crop oomycete disease. IMPORTANCE P. nicotianae is an oomycete pathogen that is destructive to crops. Although some oomycete inhibitors have been used during crop production, most are harmful to the ecology and lead to pathogen resistance. Alternatively, medium-chain fatty acids have been reported to exhibit antimicrobial activity in the medical field in previous studies; however, their potential as biocontrol agents has rarely been evaluated. Our in vivo and in vitro analyses revealed that the medium-chain fatty acid 2E,4E-decadienoic acid (DDA) displayed specific inhibitory activity against oomycetes. Further analysis indicated that DDA may acted on multiple targets in P. nicotianae, especially on the cell membrane and mitochondria. Our findings highlight the potential of DDA in controlling oomycete diseases. In conclusion, these results provide insights regarding the future use of green and environment-friendly anti-oomycete natural products for the prevention and control of crop oomycete diseases.


Asunto(s)
Fungicidas Industriales , Phytophthora , Antioxidantes/farmacología , Bacillus subtilis , Técnicas de Cocultivo , Productos Agrícolas , Ecosistema , Fungicidas Industriales/farmacología , Humanos , Hypocreales , Enfermedades de las Plantas/prevención & control
6.
Front Microbiol ; 13: 880874, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35516422

RESUMEN

Mangrove is a unique marine ecosystem growing in the intertidal zone of tropical and subtropical coast, with the characteristics of hypoxia tolerance, high salinity, and high humidity. In order to discover novel leading compounds with potent phytotoxicity, seven pairs of azaphilones E/Z isomers, isochromophilone H (1a/1b), sclerotiorins A and B (2a/2b and 3a/3b), ochlephilone (4a/4b), isochromophilone IV (5a/5b), isochromophilone J (6a/6b), and isochromophilone I (7a/7b), were isolated from the culture broth of the mangrove-derived fungus, the Penicillium sclerotiorum HY5, by various chromatographic methods. Among them, 1a, 1b, 2a, 3a, 4a, 5a, 6a, and 6b were new compounds. Their chemical structures and absolute configurations were elucidated based on high resolution electrospray ionization mass spectroscopy (HRESIMS), 1D/2D nuclear magnetic resonance (NMR) spectroscopic analysis, and comparisons of electronic circular dichroism (ECD) data. Compounds 3, 4, and 7 exhibited potent phytotoxicity against the growth of radicle and plumule on Amaranthus retroflexus L., with EC50 values ranging from 234.87 to 320.84 µM, compared to the positive control glufosinate-ammonium, with EC50 values of 555.11 µM for radicle, and 656.04 µM for plumule. Compounds 4 and 7 also showed inhibitory effects on the growth of velvetleaf (Abutilon theophrasti Medikus), with EC50 values ranging from 768.97 to 1,201.52 µM. This study provides new leading compounds for the research and development of marine-derived bioherbicides.

7.
Phytochemistry ; 197: 113125, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35157922

RESUMEN

The filamentous fungi Fusarium sp. are well-known for their ability to produce abundant specialised metabolites with attractive chemical structures and bioactivities. In this study, chemical analyses of the endophyte F. equiseti D39 led to the isolation and identification of two pairs of undescribed 3-decalinoyltetramic acids (3DTAs) E/Z diastereomers, decalintetracids A and B. Their structures were elucidated by comprehensive spectroscopic analysis and quantum-chemical calculations. Although 3DTAs were commonly reported from fungi, decalintetracid A possessed an unprecedented tricyclo [7.2.1.02,7] dodecane skeleton, which added the diversity of these fungal metabolites. In addition, decalintetracid B was featured by a unique 6/6/5 ring system core. A plausible biosynthetic pathway for decalintetracids A and B was proposed. Both compounds exhibited phytotoxicity toward Amaranthus retroflexus L. and Amaranthus hybrid, indicating their potential as natural herbicides.


Asunto(s)
Alcaloides , Fusarium , Alcaloides/metabolismo , Endófitos , Fusarium/química , Pirrolidinonas
8.
Front Microbiol ; 12: 689527, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34234763

RESUMEN

Plant diseases caused by phytopathogenic fungi can lead to huge losses in the agricultural fields and therefore remain a continuous threat to the global food security. Chemical-based fungicides contributed significantly in securing crop production. However, indiscriminate application of fungicides has led to increased chemical resistance and potential risks to human health and environment. Thus, there is an urgent need for searching for new bioactive natural products and developing them into new biopesticides. Fungal endophytes, microorganisms that reside in the fresh tissues of living plants, are regarded as untapped sources of novel natural products for exploitation in agriculture and/or medicine. Chemical examination of endophytic fungi has yielded enormous antifungal natural products with potential use in the development of biopesticides. This review summarizes a total of 132 antifungal metabolites isolated from fungal endophytes in the past two decades. The emphasis is on the unique chemical diversity of these metabolic products, together with their relevant antifungal properties. Moreover, some "star molecules," such as griseofulvin and trichothecene, as well as their synthetic derivatives that possess high potential as candidates of new natural fungicides, are also presented herein.

9.
J Asian Nat Prod Res ; 23(3): 250-257, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32077325

RESUMEN

OSMAC approach was performed on the soft coral-derived fungus Trichoderma harzianum (XS-20090075) leading to the significant changes of its secondary metabolites by using two different cultures. A new naphthalene derivative, trichoharzin B (1) and a new natural product, methyl-trichoharzin (2) were isolated by using rice medium. Whereas, a new natural product, ethyl 2-bromo-4-chloroquinoline-3-carboxylate (9) was obtained by using Czapek's medium. Their structures were established by extensive spectroscopic investigation. The absolute configuration of 5 was determined by single-crystal X-ray diffraction. Compound 9 was the first halogenate quinoline derivative isolated from the genus of Trichoderma.


Asunto(s)
Antozoos , Quinolinas , Trichoderma , Animales , Hypocreales , Estructura Molecular , Naftalenos
10.
J Agric Food Chem ; 68(40): 11207-11214, 2020 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-32915561

RESUMEN

Fungi have been proved as promising and prolific sources of functional secondary metabolites with potent agricultural applications. In this study, 14 xanthone derivatives (1-14), including six new ones, versicones I-N (1-4, 7, 11), and a biogenetically related derivative (15), were isolated from the alga-derived fungus Aspergillus versicolor D5. Their structures were elucidated by comprehensive spectroscopic methods. Versicone L (4) exhibited a broad antifungal spectrum and prominent inhibitory effects on Botrytis cinerea at a minimum inhibitory concentration (MIC) of 152 µM, 7-fold stronger than that of the positive control, carbendazim (MIC = 1.05 × 103 µM). Dihydrosterigmatocystin (13) showed strong antifungal activity toward B. cinerea at MIC = 38.3 µM, almost 30-fold stronger than that of carbendazim. Meanwhile, 13 exhibited potent herbicidal activity toward Amaranthus retroflexus L. with an MIC of 24.5 µM, approximately 4-fold stronger than that of the positive control, glyphosate (MIC = 94.7 µM). Additionally, 13 also displayed remarkable activity against other weeds belonging to Amaranth sp. Analysis of the structure-herbicidal activity relationship indicated that the bifuranic ring played an important role in xanthone phytotoxicity and the presence of a double bond in the furan ring could decrease phytotoxicity. This study indicated that xanthones can be served as promising candidates for lead compounds of agrochemicals.


Asunto(s)
Antifúngicos/química , Antifúngicos/farmacología , Aspergillus/química , Herbicidas/química , Herbicidas/farmacología , Xantonas/química , Xantonas/farmacología , Amaranthus/efectos de los fármacos , Amaranthus/crecimiento & desarrollo , Aspergillus/aislamiento & purificación , Botrytis/efectos de los fármacos , Botrytis/crecimiento & desarrollo , China , Chlorophyta/microbiología , Pruebas de Sensibilidad Microbiana , Estructura Molecular
11.
Nanomaterials (Basel) ; 10(9)2020 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-32858933

RESUMEN

Ammonia modified graphene-carbon nanotubes/continuous carbon fiber reinforced epoxy unidirectional multiscale composites (AMGNS-MWCNT/CFEP) were prepared by adding ammonia modified graphene and carbon nanotubes to an epoxy matrix to reduce agglomeration of carbon nanofillers in the epoxy matrix and improve composites properties. Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), and universal testing machines were used to characterize the properties of carbon nanofillers, AMGNS-MWCNT/epoxy nanocomposites, and AMGNS-MWCNT/CFEP unidirectional composites. When the AMGNS-MWCNT content was 1.0 wt%, flexural strength, the flexural modulus and interlaminar shear strength of AMGNS-MWCNT/CFEP unidirectional composites reached the maximum value of 1520.3 MPa, 138.88 GPa, and 87.80 MPa, respectively, which were 12.5%, 9.42%, and 10.1% higher than that of carbon fiber reinforced epoxy unidirectional composites (CFEP). The synergistic mechanism of two carbon nanofillers in the matrix is discussed.

12.
Front Microbiol ; 11: 1495, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32676071

RESUMEN

A new polyketide derivative, nafuredin C (1), a novel heterocyclic dipeptide, trichodermamide G (3), together with four known biogenetically related compounds nafuredin A (2), trichodermamide A (4), aspergillazin A (5), and peniisocoumarin H (6), were isolated from the mangrove-derived fungus Trichoderma harzianum D13. Their structures, including their absolute configurations, were determined by spectroscopic analysis and time-dependent density functional theory-electronic circular dichroism (ECD) calculations. Trichodermamide G was found to be a novel epithiodiketopiperazine derivative with an unprecedented cyclic system containing a sulfur bridge, and nafuredin C represented the third nafuredin derivative of these homologous compounds. The new compound nafuredin C exhibited obvious antifungal activity against Magnaporthe oryzae with a minimum inhibitory concentration (MIC) of 8.63 µM, which is on the same order of magnitude as the positive control carbendazim (MIC = 3.27 µM).

13.
Front Microbiol ; 11: 572, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32318046

RESUMEN

The soft coral-derived fungus Trichoderma harzianum (XS-20090075) was found to be a potential strain to produce substantial new compounds in our previous study. In order to explore its potential to produce more metabolites, chemical epigenetic manipulation was used on this fungus to wake its sleeping genes, leading to the significant changes of its secondary metabolites by using a histone deacetylase (HDAC) inhibitor. The most obvious difference was the original main products harziane diterpenoids were changed into cyclonerane sesquiterpenoids. Three new terpenoids were isolated from the fungal culture treated with 10 µM sodium butyrate, including cleistanthane diterpenoid, harzianolic acid A (1), harziane diterpenoid, harzianone E (2), and cyclonerane sesquiterpenoid, 3,7,11-trihydroxy-cycloneran (3), together with 11 known sesquiterpenoids (4-14). The absolute configurations of 1-3 were determined by single-crystal X-ray diffraction, ECD and OR calculations, and biogenetic considerations. This was the first time to obtain cleistanthane diterpenoid and africane sesquiterpenoid from genus Trichoderma, and this was the first chlorinated cleistanthane diterpenoid. These results demonstrated that the chemical epigenetic manipulation should be an efficient technique for the discovery of new secondary metabolites from marine-derived fungi.

14.
Microorganisms ; 8(2)2020 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-32028717

RESUMEN

Symbiotic associations between leguminous plants and their nodule microbiome play a key role in sustainable agriculture by facilitating the fixation of atmospheric nitrogen and enhancing plant stress resistance. This study aimed to decipher the root nodule microbiome of two halophytic legumes, Sesbania cannabina and Glycine soja, which grow in saline soils of the Yellow River Delta, China, using PacBio's circular consensus sequencing for full-length bacterial 16S rRNA gene to obtain finer taxonomic information. The cultivated legume Glycine max was used for comparison. We identified 18 bacterial genera and 55 species in nodule samples, which mainly classified to Proteobacteria, and rhizobial genus Ensifer was the predominant group. The three legumes showed similarity in operational taxonomic unit (OTU) diversity but distinction in OTU richness, indicating that they harbor similar bacterial species with different relative contents. The results of principal coordinates analysis and ANOSIM tests indicated that G. soja and G. max have similar nodule bacterial communities, and these communities differ from that of S. cannabina. Wild legumes S. cannabina and G. soja both harbored a higher number of rhizobia, while G. max possessed more non-rhizobial bacteria. These differences could be associated with their adaptability to saline-alkali stress and revealed clues on the nodule endophytes with relative importance of culturable rhizobial symbionts.

15.
J Agric Food Chem ; 67(43): 11994-12001, 2019 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-31618578

RESUMEN

Bioactivity-guided isolation of the endophytic fungus Fusarium sambucinum TE-6L residing in Nicotiana tabacum L. led to the discovery of two new angularly prenylated indole alkaloids (PIAs) with pyrano[2,3-g]indole moieties, amoenamide C (1) and sclerotiamide B (2), and four known biosynthetic congeners (3-6). Their structures were determined by comprehensive spectroscopic techniques, electronic circular dichroism (ECD), and X-ray diffraction. Compound 1 containing the bicyclo[2.2.2]diazaoctane core and indoxyl unit is rarely reported. All the compounds were evaluated for their antimicrobial and insecticidal activities. Notably, compounds 1-3 showed potent inhibitory effects against three human- and one plant-pathogenic bacterium, and seven plant-pathogenic fungi. Compounds 2-4 also exhibited remarkable larvicidal activity against first instar larvae of the cotton bollworm Helicoverpa armigera with mortality rates of 70.2%, 83.2%, and 70.5%, respectively. Further toxicity tests on zebrafish embryos were performed to evaluate the potential toxicity of PIAs. Of significance was that compound 3 in particular exhibited the highest activities but the lowest effects on the hatching of embryos among all the compounds. This study provides a basis for understanding developmental toxicity of PIAs exposure to zebrafish embryos, and also indicates the potential environmental risks of other natural compounds exposure in the aquatic ecosystem.


Asunto(s)
Antiinfecciosos/química , Endófitos/química , Fusarium/química , Alcaloides Indólicos/química , Insecticidas/química , Animales , Antiinfecciosos/metabolismo , Antiinfecciosos/farmacología , Bacterias/efectos de los fármacos , Endófitos/aislamiento & purificación , Hongos/efectos de los fármacos , Fusarium/aislamiento & purificación , Alcaloides Indólicos/metabolismo , Alcaloides Indólicos/farmacología , Insecticidas/metabolismo , Insecticidas/farmacología , Larva/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Mariposas Nocturnas/efectos de los fármacos , Nicotiana/microbiología , Pez Cebra/embriología
16.
J Nat Prod ; 82(11): 3201-3204, 2019 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-31659905

RESUMEN

A novel perylenequinone-related compound, alternatone A (1), with an unprecedented tricyclo[6.3.1.02,7] dodecane skeleton, together with three known perylenequinones, altertoxin I (2), stemphyperylenol (3), and alterperylenol (4), was isolated from the soft-coral-derived fungus Alternaria alternata L3111'. Their structures including absolute configurations were elucidated on the basis of comprehensive spectroscopic analysis, electronic circular dichroism calculations, and X-ray diffraction data. Compound 4 showed cytotoxicity against A-549, HCT-116, and HeLa cell lines with IC50 values of 2.6, 2.4, and 3.1 µM, respectively. A possible biosynthetic pathway of 1 was proposed.


Asunto(s)
Alternaria/química , Antozoos/microbiología , Perileno/análogos & derivados , Quinonas/química , Quinonas/farmacología , Animales , Antibacterianos/química , Antibacterianos/farmacología , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacología , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Estructura Molecular , Perileno/química , Perileno/farmacología , Difracción de Rayos X
17.
Sci Rep ; 9(1): 13345, 2019 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-31527674

RESUMEN

Two new harziane diterpene lactones, possessing a 6/5/7/5-fused carbocyclic core containing a lactone ring system, harzianelactones A and B (1 and 2), and five new harziane diterpenes, harzianones A-D (3-6) and harziane (7), were isolated from the soft coral-derived fungus Trichoderma harzianum XS-20090075. Their structures were determined by extensive NMR spectroscopic data, ECD and OR calculations, as well as X-ray diffraction. The isolated compounds exhibited potent phytotoxicity against seedling growth of amaranth and lettuce. Harziane diterpenes were rarely reported for their remarkably bioactivities, and it was the first report to study the phytotoxicity of harziane diterpenes, which provide a new application of such compounds in agriculture for future research.


Asunto(s)
Amaranthus/crecimiento & desarrollo , Diterpenos/química , Herbicidas/farmacología , Lactuca/crecimiento & desarrollo , Toxinas Biológicas/farmacología , Trichoderma/química , Amaranthus/efectos de los fármacos , Animales , Antozoos/microbiología , Diterpenos/aislamiento & purificación , Lactonas/química , Lactonas/aislamiento & purificación , Lactuca/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Estructura Molecular , Malezas/efectos de los fármacos , Difracción de Rayos X
18.
Small ; 15(46): e1903873, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31550081

RESUMEN

SnS2 has been widely studied as an anode material for sodium-ion batteries (SIBs) based on the high theoretical capacity and layered structure. Unfortunately, rapid capacity decay associated with volume variation during cycling limits practical application. Herein, SnS2 /Co3 S4 hollow nanocubes anchored on S-doped graphene are synthesized for the first time via coprecipitation and hydrothermal methods. When applied as the anode for SIBs, the sample delivers a distinguished charge specific capacity of 1141.8 mAh g-1 and there is no significant capacity decay (0.1 A g-1 for 50 cycles). When the rate is increased to 0.5 A g-1 , it presents 845.7 mAh g-1 after cycling 100 times. Furthermore, the composite also exhibits an ultrafast sodium storage capability where 392.9 mAh g-1 can be obtained at 10 A g-1 and the charging time is less than 3 min. The outstanding electrochemical properties can be ascribed to the enhancement of conductivity for the addition of S-doped graphene and the existence of p-n junctions in the SnS2 /Co3 S4 heterostructure. Moreover, the presence of mesopores between nanosheets can alleviate volume expansion during cycling as well as being beneficial for the migration of Na+ .

19.
Molecules ; 23(12)2018 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-30572672

RESUMEN

Chromatographic separation of a marine algal-derived endophytic fungus Penicillium chrysogenum AD-1540, which was isolated from the inner tissue of the marine red alga Grateloupia turuturu, yielded two new benzophenone derivatives, chryxanthones A and B (compounds 1 and 2, respectively). Their structures were undoubtedly determined by comprehensive analysis of spectroscopic data (1D/2D NMR and HRESIMS). The relative and absolute configurations were assigned by analysis of the coupling constants and time-dependent density functional theory (TDDFT) calculations of their electronic circular dichroism (ECD) spectra, respectively. Both compounds possessed an unusual dihydropyran ring (ring D) fused to an aromatic ring, rather than the commonly occurring prenyl moiety, and a plausible biosynthetic pathway was postulated. The cytotoxicities of compounds 1 and 2 were evaluated against six human cell lines, and both of the compounds demonstrated weak to moderate cytotoxicities with IC50 values ranging from 20.4 to 46.4 µM. These new compounds further demonstrate the potential of marine-derived fungi as an untapped source of pharmaceutical components with unique properties that could be developed as drug candidates.


Asunto(s)
Benzofenonas/química , Benzofenonas/farmacología , Penicillium chrysogenum/química , Línea Celular , Supervivencia Celular/efectos de los fármacos , Dicroismo Circular , Humanos , Espectroscopía de Resonancia Magnética , Estructura Molecular , Policétidos/química , Policétidos/farmacología
20.
Molecules ; 23(6)2018 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-29874868

RESUMEN

Phyllodiumpulchellum has been traditionally used as a medicinal herb because of its health-promoting effects, such as its hepatoprotective and antioxidant activities. In the present study, the petroleum ether fraction, ethyl acetate fraction, n-butanol fraction, and aqueous fraction were successively obtained from the ethanol extract of P. pulchellum. Two fractions, ethyl acetate fraction and n-butanol fraction, were found to display hepatoprotective and antioxidant activities. Further chemical investigation of the active fractions led to the isolation of its main constituents, including 11 flavonoids (1⁻11) and 8 indole alkaloids (12⁻19). There were 9 flavonoids (1⁻9) that were obtained from the ethyl acetate fraction, and 2 flavonoids (10 and 11) and 8 alkaloids (12⁻19) from the n-butanol fraction. Compounds 1⁻11 and 16⁻19 were isolated for the first time from P. pulchellum, and 1, 2, 8, 11, and 18 were obtained from the genus Phyllodium initially. Subsequently, the isolated compounds were evaluated for their in vitro hepatoprotective effects on the human normal hepatocyte cell line L-O2 injured by d-galactosamine and radical scavenging activities against 1,1-diphenyl-2-picrylhydrazyl (DPPH). The flavonoids (-)-epigallocatechin (5) and (-)-epicatechin (6) exhibited prominent hepatoprotective activities with higher cell viability values (65.53% and 62.40% at 10 µM·mL-1, respectively) than the positive control, silymarin (61.85% at 10 µM·mL-1). In addition, compared with the positive control of vitamin C (IC50: 5.14 µg·mL-1), (-)-gallocatechin (3) and (-)-epigallocatechin (5) exhibited stronger antioxidant activities with IC50 values of 3.80 and 3.97 µg·mL-1, respectively. Furthermore, the total flavonoids from P. pulchellum were characterized using a high-performance liquid chromatography-linear ion trap quadrupole-Orbitrap-mass spectrometry (HPLC-LTQ-Orbitrap-MS). In total, 34 flavonoids were tentatively identified, which had not been previously reported from P. pulchellum. In addition, we performed a semi-quantitative analysis of the isolated flavonoids. The contents of compounds 1⁻11 were 3.88, 17.73, 140.35, 41.93, 27.80, 4.34, 0.01, 0.20, 9.67, 795.85, and 5.23 µg·g-1, respectively. In conclusion, this study revealed that the flavonoids that were isolated from P. pulchellum showed hepatoprotective and antioxidant activities, indicating that, besides alkaloids, the flavonoids should be the potential pharmacodynamic ingredients that are responsible for the hepatoprotective and antioxidant activities of P. pulchellum.


Asunto(s)
Antioxidantes/farmacología , Fabaceae/química , Hígado/efectos de los fármacos , Antioxidantes/química , Línea Celular , Cromatografía Líquida de Alta Presión/métodos , Hepatocitos/efectos de los fármacos , Humanos , Espectrometría de Masas/métodos , Relación Estructura-Actividad
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