Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35
Filtrar
1.
Small ; 20(1): e2305322, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37641186

RESUMO

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.

2.
Small ; : e2403871, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39004859

RESUMO

The slow reaction kinetics and severe shuttle effect of lithium polysulfide make Li-S battery electrochemical performance difficult to meet the demands of large electronic devices such as electric vehicles. Based on this, an electrocatalyst constructed by metal phase material (MoS2) and semiconductor phase material (SnS2) with ohmic contact is designed for inhibiting the dissolution of lithium polysulfide with improving the reaction kinetics. According to the density-functional theory calculations, it is found that the heterostructured samples with ohmic contacts can effectively reduce the reaction-free energy of lithium polysulfide to accelerate the sulfur redox reaction, in addition to the excellent electron conduction to reduce the overall activation energy. The metallic sulfide can add more sulfophilic sites to promote the capture of polysulfide. Thanks to the ohmic contact design, the carbon nanotube-MoS2-SnS2 achieved a specific capacity of 1437.2 mAh g-1 at 0.1 C current density and 805.5 mAh g-1 after 500 cycles at 1 C current density and is also tested as a pouch cell, which proves to be valuable for practical applications. This work provides a new idea for designing an advanced and efficient polysulfide catalyst based on ohmic contact.

3.
Small ; : e2403079, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38829022

RESUMO

Phosphate-based electrolyte propels the advanced battery system with high safety. Unfortunately, restricted by poor electrochemical stability, it is difficult to be compatible with advanced lithium metal anodes and Ni-rich cathodes. To alleviate these issues, the study has developed a phosphate-based localized high-concentration electrolyte with a nitrate-driven solvation structure, and the nitrate-derived N-rich inorganic interface shows excellent performance in stabilizing the LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode interface and modulating the lithium deposition morphology on the anode. The results show that the Li|| NCM811 cell has exceptional long-cycle stability of >80% capacity retention after 800 cycles at 4.3 V, 1 C. A more prominent capacity retention rate of 93.3% after 200 cycles can be reached with the high voltage of 4.5 V. While being compatible with the phosphate-based electrolyte with good flame retardancy and the good electrochemical stability of Ni-rich lithium metal battery (LMBs) systems, the present work expands the construction of anion-rich solvation structures, which is expected to promote the development of the high-performance LMBs with safety.

4.
Small ; : e2402123, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38804876

RESUMO

The localized high-concentration electrolyte (LHCE) propels the advanced high-voltage battery system. Sulfone-based LHCE is a transformative direction compatible with high energy density and high safety. In this work, the application of lithium bis(trifluoromethanesulphonyl)imide and lithium bis(fluorosulfonyl)imide (LiFSI) in the LHCE system constructed from sulfolane and 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether (TTE) is investigated. The addition of diluent causes an increase of contact ion pairs and ionic aggregates in the solvation cluster and an acceptable quantity of free solvent molecules. A small amount of LiFSI as an additive can synergistically decompose with TTE on the cathode and participate in the construction of both electrode interfaces. The designed electrolyte helps the Ni-rich system to cycle firmly at a high voltage of 4.5 V. Even with high mass load and lean electrolyte, it can keep a reversible specific capacity of 91.5% after 50 cycles. The constructed sulfone-based electrolyte system exhibits excellent thermal stability far beyond the commercial electrolytes. Further exploration of in-situ gelation has led to a quick conversion of the designed liquid electrolyte to the gel state, accompanied by preserved stability, which provides a direction for the synergistic development of LHCE with gel electrolytes.

5.
Ecotoxicol Environ Saf ; 247: 114273, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36356529

RESUMO

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.


Assuntos
Alcaloides , Amaranthus , Toxinas Biológicas , Esterigmatocistina , Metabolômica , Aminoácidos
6.
J Asian Nat Prod Res ; 23(3): 250-257, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32077325

RESUMO

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.


Assuntos
Antozoários , Quinolinas , Trichoderma , Animais , Hypocreales , Estrutura Molecular , Naftalenos
7.
Small ; 15(46): e1903873, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31550081

RESUMO

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+ .

8.
J Nat Prod ; 82(11): 3201-3204, 2019 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-31659905

RESUMO

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.


Assuntos
Alternaria/química , Antozoários/microbiologia , Perileno/análogos & derivados , Quinonas/química , Quinonas/farmacologia , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Perileno/química , Perileno/farmacologia , Difração de Raios X
9.
Mar Drugs ; 16(1)2018 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-29346329

RESUMO

Thirty-one isolates belonging to eight genera in seven orders were identified from 141 strains that were isolated from several marine plants. Alternaria sp. and Fusarium sp. were found to be the predominant fungi. Evaluation of the anti-phytopathogenic bacterial and fungal activities, as well as the cytotoxicity of these 31 extracts, revealed that most of them displayed different levels of bioactivities. Due to their interesting bioactivities, two fungal strains-Fusarium equiseti (P18) and Alternaria sp. (P8)-were selected for chemical investigation and compounds 1-4 were obtained. The structure of 1 was elucidated by 1D and 2D NMR analysis, as well as high-resolution electrospray ionization mass spectroscopy (HRESIMS), and the absolute configuration of its stereogenic carbon (C-11) was established by comparison of the experimental and calculated electronic circular-dichroism (ECD) spectra. Moreover, alterperylenol (4) exhibited antibacterial activity against Clavibacter michiganensis with a minimum inhibitory concentration (MIC) of 1.95 µg/mL, which was 2-fold stronger than that of streptomycin sulfate. Additionally, an antibacterial mechanism study revealed that 4 caused membrane hyperpolarization without evidence of destruction of cell membrane integrity. Furthermore, stemphyperylenol (3) displayed potent antifungal activity against Pestallozzia theae and Alternaria brassicicola with MIC values equal to those of carbendazim. The cytotoxicity of 1 and 2 against human lung carcinoma (A-549), human cervical carcinoma (HeLa), and human hepatoma (HepG2) cell lines were also evaluated.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Organismos Aquáticos/química , Misturas Complexas/farmacologia , Citotoxinas/farmacologia , Fungos/química , Fungos/metabolismo , Células A549 , Alternaria/química , Antibacterianos/química , Antifúngicos/química , Bactérias/efeitos dos fármacos , Linhagem Celular Tumoral , Misturas Complexas/química , Citotoxinas/química , Fungos/efeitos dos fármacos , Fusarium/química , Células HeLa , Células Hep G2 , Humanos , Testes de Sensibilidade Microbiana/métodos
10.
Molecules ; 23(12)2018 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-30572672

RESUMO

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.


Assuntos
Benzofenonas/química , Benzofenonas/farmacologia , Penicillium chrysogenum/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Dicroísmo Circular , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Policetídeos/química , Policetídeos/farmacologia
11.
Molecules ; 23(6)2018 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-29874868

RESUMO

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.


Assuntos
Antioxidantes/farmacologia , Fabaceae/química , Fígado/efeitos dos fármacos , Antioxidantes/química , Linhagem Celular , Cromatografia Líquida de Alta Pressão/métodos , Hepatócitos/efeitos dos fármacos , Humanos , Espectrometria de Massas/métodos , Relação Estrutura-Atividade
12.
Mar Drugs ; 15(6)2017 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-28587090

RESUMO

Three new diphenyl ether derivatives-phomaethers A-C (1-3) and five known compounds-including a diphenyl ether analog, 2,3'-dihydroxy-4-methoxy-5',6-dimethyl diphenyl ether (4); and four isocoumarin derivatives, diaportinol (5), desmethyldiaportinol (6), citreoisocoumarinol (7), and citreoisocoumarin (8)-were isolated from a gorgonian-derived fungus Phoma sp. (TA07-1). Their structures were elucidated by extensive spectroscopic investigation. The absolute configurations of 1 and 2 were determined by acid hydrolysis reactions. It was the first report to discover the diphenyl glycoside derivatives from coral-derived fungi. Compounds 1, 3, and 4 showed selective strong antibacterial activity against five pathogenic bacteria with the minimum inhibiting concentration (MIC) values and minimum bactericidal concentration (MBC) values between 0.156 and 10.0 µM.


Assuntos
Antibacterianos/química , Ascomicetos/química , Isocumarinas/química , Éteres Fenílicos/química , Antibacterianos/farmacologia , Fatores Biológicos/química , Fatores Biológicos/farmacologia , Isocumarinas/farmacologia , Testes de Sensibilidade Microbiana/métodos , Éteres Fenílicos/farmacologia
13.
Molecules ; 21(2): 160, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26828473

RESUMO

Two new naphthalenones, corynenones A and B (1 and 2), and one new depsidone, corynesidone E (3), together with one known depsidone, corynesidone A (4) and two known diphenyl ethers, corynethers A (5) and B (6), were isolated from the sponge-derived fungus Corynespora cassiicola XS-20090I7. Their structures including absolute configurations were determined by spectroscopic data and electronic circular dichroism (ECD) spectra. Compounds 4 and 5 showed cytotoxicity against human promyelocytic leukemia HL-60 and human cervical carcinoma HeLa cell lines.


Assuntos
Depsídeos/isolamento & purificação , Lactonas/isolamento & purificação , Naftalenos/isolamento & purificação , Poríferos/microbiologia , Saccharomycetales/química , Animais , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dicroísmo Circular , Depsídeos/química , Depsídeos/farmacologia , Células HL-60 , Células HeLa , Humanos , Lactonas/química , Lactonas/farmacologia , Estrutura Molecular , Naftalenos/química , Naftalenos/farmacologia
14.
J Nat Prod ; 78(2): 286-93, 2015 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-25594263

RESUMO

Twelve new chromone derivatives, corynechromones A-L (1-12), were isolated from the sponge-derived fungus Corynespora cassiicola XS-200900I7. Among them, 1/2, 3/4, 5/6, and 7/8 were pairs of epimers. The planar structures were determined by extensive NMR spectroscopic data. The absolute configurations of 1-10 were assigned by the modified Mosher's method and TDDFT ECD calculations together with comparison of their CD spectra. These are the first chromone derivatives reported from the genus Corynespora. A possible rule to determine the absolute configurations at C-2 in chromone derivatives by CD was proposed.


Assuntos
Ascomicetos/química , Cromonas/isolamento & purificação , Poríferos/microbiologia , Animais , Bacillus cereus/efeitos dos fármacos , Bacillus subtilis/efeitos dos fármacos , Incrustação Biológica/prevenção & controle , Inibidores da Colinesterase/química , Inibidores da Colinesterase/isolamento & purificação , Inibidores da Colinesterase/farmacologia , Cromonas/química , Cromonas/farmacologia , Enterococcaceae/efeitos dos fármacos , Biologia Marinha , Testes de Sensibilidade Microbiana , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Pseudomonas putida/efeitos dos fármacos , Staphylococcus/efeitos dos fármacos , Estereoisomerismo , Inibidores da Topoisomerase I/química , Inibidores da Topoisomerase I/isolamento & purificação , Inibidores da Topoisomerase I/farmacologia , Vibrio/efeitos dos fármacos
15.
J Nat Prod ; 78(9): 2310-4, 2015 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-26291474

RESUMO

Three new azaphilone derivatives, pinophilins D-F (1-3), and one new diphenyl ether derivative, hydroxypenicillide (10), together with nine known compounds (4-9, 11-13), were isolated from the gorgonian-derived fungus Penicillium pinophilum XS-20090E18. Their structures including absolute configurations were determined by spectroscopic data, chemical conversions, the ECD exciton chirality method, and ECD calculations. Compounds 10-13 exhibited inhibitory activity against the larval settlement of the barnacle Balanus amphitrite at nontoxic concentrations. Compounds 10 and 11 showed cytotoxicity against Hep-2, RD, and HeLa cell lines.


Assuntos
Antozoários/microbiologia , Benzopiranos/isolamento & purificação , Penicillium/química , Éteres Fenílicos/isolamento & purificação , Pigmentos Biológicos/isolamento & purificação , Animais , Benzopiranos/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Oceanos e Mares , Éteres Fenílicos/química , Pigmentos Biológicos/química
16.
Chem Biodivers ; 12(9): 1407-14, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26363884

RESUMO

One new merosesquiterpenoid, craterellin D (1), along with one known analog, craterellin A (2), and five known ten-membered macrolides, 3-7, were isolated from a soft coral-derived Lophiostoma sp. fungus. The absolute configuration of 1 was established based on biogenetic consideration with the co-isolated analog 2, whose configuration was determined by modified Mosher's method and single-crystal X-ray diffraction analysis using CuKα radiation. The absolute configuration of 3 was determined by X-ray diffraction analysis using CuKα radiation. Compounds 2 and 3 showed antibacterial activities against Bacillus cereus with a MIC value of 3.12 µM.


Assuntos
Antozoários/microbiologia , Antibacterianos/química , Ascomicetos/química , Macrolídeos/química , Sesquiterpenos/química , Animais , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Bacillus cereus/efeitos dos fármacos , Cristalografia por Raios X , Macrolídeos/isolamento & purificação , Macrolídeos/farmacologia , Modelos Moleculares , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia
17.
ACS Appl Mater Interfaces ; 16(15): 19730-19741, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38591140

RESUMO

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.

18.
J Nat Prod ; 76(4): 547-53, 2013 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-23527875

RESUMO

Two new prenylated indole alkaloids, 17-epi-notoamides Q and M (1 and 2), and two new phenyl ether derivatives, cordyols D and E (9 and 13), together with 10 known compounds (3-8, 10-12, 14) were isolated from a marine-derived Aspergillus sp. fungus. Among them, 1/5 and 2/4 were pairs of epimers. The planar structures and absolute configurations of the new compounds were determined by extensive NMR spectroscopic data as well as CD spectra. The absolute configuration of 3 was confirmed by single-crystal X-ray diffraction analysis for the first time. All isolated metabolites (1-14) and eight synthetic phenyl ether derivatives (12a, 14a-14g) were evaluated for their antibacterial activities in vitro. The polybromide phenyl ether 14g showed pronounced antibacterial activity against Staphylococcus epidermidis with an MIC value of 0.556 µM, stronger than that of the positive control ciprofloxacin (MIC = 3.13 µM).


Assuntos
Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Aspergillus/química , Alcaloides Indólicos/isolamento & purificação , Alcaloides Indólicos/farmacologia , Animais , Antozoários/microbiologia , Antibacterianos/química , Cristalografia por Raios X , Alcaloides Indólicos/química , Biologia Marinha , Testes de Sensibilidade Microbiana , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Staphylococcus epidermidis/efeitos dos fármacos
19.
Mar Drugs ; 11(6): 2054-68, 2013 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-23752358

RESUMO

One new phenylalanine derivative 4'-OMe-asperphenamate (1), along with one known phenylalanine derivative (2) and two new cytochalasins, aspochalasin A1 (3) and cytochalasin Z24 (4), as well as eight known cytochalasin analogues (5-12) were isolated from the fermentation broth of Aspergillus elegans ZJ-2008010, a fungus obtained from a soft coral Sarcophyton sp. collected from the South China Sea. Their structures and the relative configurations were elucidated using comprehensive spectroscopic methods. The absolute configuration of 1 was determined by chemical synthesis and Marfey's method. All isolated metabolites (1-12) were evaluated for their antifouling and antibacterial activities. Cytochalasins 5, 6, 8 and 9 showed strong antifouling activity against the larval settlement of the barnacle Balanus amphitrite, with the EC50 values ranging from 6.2 to 37 µM. This is the first report of antifouling activity for this class of metabolites. Additionally, 8 exhibited a broad spectrum of antibacterial activity, especially against four pathogenic bacteria Staphylococcus albus, S. aureus, Escherichia coli and Bacillus cereus.


Assuntos
Antozoários/microbiologia , Aspergillus/química , Citocalasinas/farmacologia , Fenilalanina/farmacologia , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Aspergillus/isolamento & purificação , Bactérias/efeitos dos fármacos , Incrustação Biológica/prevenção & controle , China , Citocalasinas/química , Citocalasinas/isolamento & purificação , Fenilalanina/análogos & derivados , Fenilalanina/isolamento & purificação , Análise Espectral
20.
J Agric Food Chem ; 71(51): 20713-20723, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38095326

RESUMO

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.


Assuntos
Anti-Infecciosos , Toxinas Biológicas , Aspergillus/metabolismo , Anti-Infecciosos/metabolismo , Toxinas Biológicas/metabolismo , Estrutura Molecular
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA