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1.
Foods ; 13(11)2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38891014

RESUMO

Plipastatin, an antimicrobial peptide produced by Bacillus subtilis, exhibits remarkable antimicrobial activity against a diverse range of pathogenic bacteria and fungi. However, the practical application of plipastatin has been significantly hampered by its low yield in wild Bacillus species. Here, the native promoters of both the plipastatin operon and the sfp gene in the mono-producing strain M-24 were replaced by the constitutive promoter P43, resulting in plipastatin titers being increased by 27% (607 mg/mL) and 50% (717 mg/mL), respectively. Overexpression of long chain fatty acid coenzyme A ligase (LCFA) increased the yield of plipastatin by 105% (980 mg/mL). A new efflux transporter, YoeA, was identified as a MATE (multidrug and toxic compound extrusion) family member, overexpression of yoeA enhanced plipastatin production to 1233 mg/mL, an increase of 157%, and knockout of yoeA decreased plipastatin production by 70%; in contrast, overexpression or knockout of yoeA in mono-producing surfactin and iturin engineered strains only slightly affected their production, demonstrating that YoeA acts as the major exporter for plipastatin. Co-overexpression of lcfA and yoeA improved plipastatin production to 1890 mg/mL, which was further elevated to 2060 mg/mL after abrB gene deletion. Lastly, the use of optimized culture medium achieved 2514 mg/mL plipastatin production, which was 5.26-fold higher than that of the initial strain. These results suggest that multiple strain engineering is an effective strategy for increasing lipopeptide production, and identification of the novel transport efflux protein YoeA provides new insights into the regulation and industrial application of plipastatin.

2.
Pharm Biol ; 62(1): 207-213, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38353248

RESUMO

CONTEXT: The effect of the active ingredients in traditional Chinese medicines on the activity of cytochrome P450 enzymes (CYP450s) is a critical factor that should be considered in TCM prescriptions. Physcion, the major active ingredient of Rheum spp. (Polygonaceae), possesses wide pharmacological activities. OBJECTIVES: The effect of physcion on CYP450 activity was investigated to provide a theoretical basis for use. MATERIALS AND METHODS: The experiments were conducted in pooled human liver microsomes (HLMs). The activity of CYP450 isoforms was evaluated with corresponding substrates and probe reactions. Blank HLMs were set as negative controls, and typical inhibitors were employed as positive controls. The inhibition model was fitted with Lineweaver Burk plots. The concentration (0, 2.5, 5, 10, 25, 50 and 100 µM physcion) and time-dependent (0, 5, 10, 15 and 30 min) effects of physcion were also assessed. RESULTS: Physcion suppressed CYP2C9, 2D6 and 3A4 in a concentration-dependent manner with IC50 values of 7.44, 17.84 and 13.50 µM, respectively. The inhibition of CYP2C9 and 2D6 was competitive with the Ki values of 3.69 and 8.66 µM, respectively. The inhibition of CYP3A4 was non-competitive with a Ki value of 6.70 µM. Additionally, only the inhibition of CYP3A4 was time-dependent with the KI and Kinact parameters of 3.10 µM-1 and 0.049 min-1, respectively. CONCLUSIONS: The inhibition of CYP450s by physcion should be considered in its clinical prescription, and the study design can be employed to evaluate the interaction of CYP450s with other herbs.


Assuntos
Citocromo P-450 CYP3A , Emodina/análogos & derivados , Microssomos Hepáticos , Humanos , Citocromo P-450 CYP2C9 , Inibidores das Enzimas do Citocromo P-450/farmacologia , Sistema Enzimático do Citocromo P-450
3.
Chemosphere ; 343: 140257, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37742767

RESUMO

A novel amidoxime-functionalized magnetic hydroxyapatite (AFNH) was successfuly fabricated to extract uranium from aqueous solution and seawater. The introduction of amidoxime group not only increased the number of active site of AFNH to speed up the adsorption rate and increase the extraction capacity, but also adjusted the optimal extraction pH from 4 to 8, which was beneficial for capturing uranium from seawater. The maximum adsorption capacity and adsorption efficiency at pH 8 were 945.2 mg g-1 and 99.2%, respectively. AFNH still had good removal efficiency (above 90%) after five cycles, indicating the good regeneration of AFNH. After uranium adsorption, AFNH could be easily recycled by magnetic separation due to its magnetism. In simulated seawater, AFNH also showed excellent uranium removal performance with high adsorption efficiency (84.9%) and adsorption capacity (1.70 mg g-1). Furthermore, the 14-day uranium extraction capacity of AFNH in natural seawater could reach 5.93 mg g-1. The SEM, FTIR, XRD and XPS analyses showed that the enhanced uranium extraction performance of AFNH was mainly attributed to electrostatic interaction, complexation and co-precipitation. In conclusion, AFNH was expected to be a candidate as adsorbent with great potential in extracting uranium from seawater.

4.
Dalton Trans ; 52(35): 12296-12307, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37585192

RESUMO

Herein, magnetic layered double oxides coated with carbon dots (MLCs) were synthesized through introducing sodium dodecylbenzene sulfonate and FeCl2 into Co/Al LDH for capturing uranium from aqueous solution. When the molar ratio of Co to Al was 4 : 1, the MLC composite possessed the strongest affinity to uranium(VI) in solution with short equilibrium time (<160 min), high adsorption efficiency (94.31%) and large removal capacity (513.85 mg g-1). The adsorption behavior of MLCs for uranium(VI) was well fitted with Langmuir and pseudo-second-order models, suggesting that the monolayer chemical adsorption was the rate-limiting step. Besides, MLC-3 could be reused by using 0.15 mol L-1 ethylene diamine tetraacetic acid as an eluent and the removal percentage still remained at a high level (>83.3%) after 5 adsorption/desorption cycles. Redox reaction, chemical complexation and electrostatic attraction were proved to play significant roles in uranium(VI) separation. Therefore, MLC-3 could be used as a potential adsorbent in uranium(VI)-containing wastewater treatment due to its excellent adsorption performance for uranium(VI).

5.
Mol Cell Probes ; 71: 101926, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37567321

RESUMO

BACKGROUND: Non-alcohol fatty liver disease (NAFLD) is the most prevalent hepatopathy in China, with few effective cures currently. This work aimed to confirm the effect of DHM in vivo/vitro and explore the potential mechanism based on a network pharmacology-based approach. METHODS: The rats were fed using a high-fat diet (HFD) to accumulate lipid. DHM at different concentrations was used to treat the HFD rats. The serum total cholesterol (TC), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were detected using ELISA kits. The target genes of DHM against NAFLD were screened by online databases. Then, the cytotoxicity of DHM in primary hepatocytes and HepG2 cells was determined by MTT reagent. qRT-PCR was used to quantify the expression level of PPAGR and CASP3 mRNA. Cell apoptosis and intracellular triglyceride (TG) were detected. RESULTS: HFD diet increased rat liver weight/body weight ratio, serum TC, ALT, and AST. But DHM treatment can reduce these elevated indicators. DHM targeted 14 potential genes in NAFLD. PPARG and CASP3 were two hub genes for DHM against NAFLD, with score factor coefficients of -7.1 and -6.8 kcal/mol. DHM reduced the increased PPARG mRNA level and intracellular TG induced by palmitic acid. DHM can reduce the increased CASP3 mRNA level and cell apoptosis induced by palmitic acid. CONCLUSION: This work demonstrates a mechanism of DHM that alleviates lipid metabolism disorder and cell apoptosis for the treatment of NAFLD, evidencing the potential application of DHM in NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Ratos , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Fígado/metabolismo , PPAR gama/metabolismo , Ácido Palmítico/metabolismo , Ácido Palmítico/farmacologia , Caspase 3/metabolismo , Farmacologia em Rede , Metabolismo dos Lipídeos/genética , Triglicerídeos/metabolismo
6.
J Agric Food Chem ; 71(28): 10683-10692, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37427858

RESUMO

Plipastatin is a cyclic lipopeptide synthesized by non-ribosomal peptide synthetases (NRPS), which has a diverse range of applications in postharvest preservation of fruits and vegetables, biological control, and feed processing. Whereas the yield of plipastatin in wild Bacillus sp. is low, its chemical structure is complex and challenging to synthesize, significantly limiting its production and application. ComQXPA-PsrfA, a quorum-sensing (QS) circuit from Bacillus amyloliquefaciens, was constructed in this study. Two QS promoters MuPsrfA and MtPsrfA, with 35 and 100% increased activity, respectively, were obtained by mutating the original promoter PsrfA. Thus, the natural promoter of plipastatin was replaced by a QS promoter to achieve the dynamic regulation of plipastatin, which increased the yield of plipastatin by 3.5 times. Integrating ComQXPA into plipastatin mono-producing M-24:MtPsrfA increased the yield of plipastatin to 3850 mg/L, representing the highest yield reported to date. Four new plipastatins were identified via UPLC-ESI-MS/MS and GC-MS analysis of fermentation products of mono-producing engineered strains. Among them, three plipastatins contained two double bonds in the fatty acid side chain, representing the first example of a new type of plipastatin. Our results indicate that the QS system ComQXPA-PsrfA of Bacillus can dynamically regulate plipastatin production, and the pipeline could be extended to the other strains to regulate target products dynamically.


Assuntos
Bacillus amyloliquefaciens , Bacillus , Bacillus subtilis , Bacillus amyloliquefaciens/genética , Espectrometria de Massas em Tandem , Bacillus/genética , Ácidos Graxos/química , Percepção de Quorum
7.
Int J Biol Macromol ; 242(Pt 3): 124998, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37236563

RESUMO

In this work, a novel g-C3N4 filled, phosphoric-crosslinked chitosan gel bead (P-CS@CN) was successfully prepared to adsorb U(VI) from water. The separation performance of chitosan was improved by introducing more functional groups. At pH 5 and 298 K, the adsorption efficiency and adsorption capacity could reach 98.0 % and 416.7 mg g-1, respectively. After adsorption, the morphological structure of P-CS@CN did not change and adsorption efficiency remained above 90 % after 5 cycles. P-CS@CN exhibited an excellent applicability in water environment based on dynamic adsorption experiments. Thermodynamic analyses demonstrated the value of ΔG, manifesting the spontaneity of U(VI) adsorption process on P-CS@CN. The positive values of ΔH and ΔS showed that the U(VI) removal behavior of P-CS@CN was an endothermic reaction, indicating that the increase of temperature was great benefit to the removal. The adsorption mechanism of P-CS@CN gel bead could be summarized as the complexation reaction with the surface functional groups. This study not only developed an efficient adsorbent for the treatment of radioactive pollutants, but also provided a simple and feasible strategy for the modification of chitosan-based adsorption materials.


Assuntos
Quitosana , Urânio , Poluentes Químicos da Água , Quitosana/química , Urânio/química , Temperatura , Termodinâmica , Água , Poluentes Químicos da Água/análise , Adsorção , Cinética , Concentração de Íons de Hidrogênio
8.
Phytochemistry ; 209: 113625, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36858338

RESUMO

The metabolites from the endophytic fungus Muyocopron laterale hosted in the medicinal plant Tylophora ovata were investigated, and five undescribed xanthones, muyocoxanthones O-S, along with seven known compounds were isolated. Their structures were elucidated by HR-ESI-MS, NMR, and ECD calculations. Compounds were evaluated for their anti-cardiomyocyte oxidative damage activity using a model of oxidative damage induced by cell hypoxia incubation. Muyocoxanthones O-Q and blennolide L exhibited moderate activity against oxidative damage to cardiomyocytes with relative viabilities of 62.4, 54.8, 60.3 and 54.9%, respectively.


Assuntos
Ascomicetos , Xantonas , Antioxidantes/farmacologia , Xantonas/química , Ascomicetos/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular
9.
ACS Synth Biol ; 12(3): 877-891, 2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-36821745

RESUMO

Although a variety of whole-cell-based biosensors have been developed for different applications in recent years, most cannot meet practical requirements due to insufficient sensing performance. Here, we constructed two sets of modular genetic circuits by serial and parallel modes capable of significantly amplifying the input/output signal in Escherichia coli. The biosensors are engineered using σ54-dependent phenol-responsive regulator DmpR as a sensor and enhanced green fluorescent protein as a reporter. Cells harboring serial and parallel genetic circuits displayed nearly 9- and 16-fold higher sensitivity than the general circuit. The genetic circuits enabled rapid detection of six phenolic contaminants in 12 h and showed the low limit of detection of 2.5 and 2.2 ppb for benzopyrene (BaP) and tetracycline (Tet), with a broad detection range of 0.01-1 and 0.005-5 µM, respectively. Furthermore, the positive rate was as high as 73% when the biosensor was applied to screen intracellular enzymes with ester-hydrolysis activity from soil metagenomic libraries using phenyl acetate as a phenolic substrate. Several novel enzymes were isolated, identified, and biochemically characterized, including serine peptidases and alkaline phosphatase family protein/metalloenzyme. Consequently, this study provides a new signal amplification method for cell-based biosensors that can be widely applied to environmental contaminant assessment and screening of intracellular enzymes.


Assuntos
Proteínas de Bactérias , Técnicas Biossensoriais , Proteínas de Bactérias/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Técnicas Biossensoriais/métodos
10.
Clin Res Hepatol Gastroenterol ; 47(1): 102067, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36513253

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is known to aggravate metabolic disturbance and increase the risk of complications. The purpose of the present study was to explore the mechanism underlying the clinical effects of ZFAS1 on NAFLD. METHODS: Expression of the ZFAS1 RNA was quantified in patients with NAFLD through reverse transcription-quantitative polymerase chain reaction. The correlations were assessed using Pearson's correlation coefficient test. The receiver operating characteristic curve was used to evaluate the identification of ZFAS1. Commercial kits were purchased to detect the pertinent parameters to establish mice models. Luciferase report assay was used to identify and confirm the presence of ZFAS1 ceRNA. RESULTS: The increase of ZFAS1 expression in patients with NAFLD was noted and the high expression level may be considered a risk factor for NAFLD. In mouse models fed with high-fat diet (HFD), the expression levels of ZFAS1 were increased; furthermore, sh-ZFAS1 reversed ZFAS1 overexpression. HFD administration resulted in liver injury, which was indicated by increased lipid deposition, aggressive oxidative stress, and imbalanced inflammatory reaction. However, sh-ZFAS1 attenuated the abovementioned adverse effects of HFD. MiR-144-5p was a ceRNA of ZFAS1; in addition, the expression of miR-144-5p was reduced in HFD-managed models and patients with NAFLD. ZFAS1 could successfully regulate the expression levels of miR-144-5p. In the present study, the negative relationship between ZFAS1 and miR-144-5p was documented. CONCLUSION: Excessive expression of ZFAS1 and its diagnostic potential was noted in patients with NAFLD. It was evident that ZFAS1 may be responsible for exacerbating the worsening of liver function.


Assuntos
Peroxidação de Lipídeos , MicroRNAs , Hepatopatia Gordurosa não Alcoólica , RNA Longo não Codificante , Animais , Camundongos , Linhagem Celular Tumoral , Inflamação/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Humanos
11.
Pharm Biol ; 60(1): 1944-1948, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36226863

RESUMO

CONTEXT: The co-administration of abemaciclib and astragaloside IV might occur in the treatment of breast cancer. OBJECTIVE: This study evaluates the interaction between abemaciclib and astragaloside IV in rats and describes the potential mechanism. MATERIALS AND METHODS: Male Sprague Dawley rats were randomly divided into four groups: single dose of abemaciclib (control), abemaciclib + 50 mg/kg/d astragaloside IV, abemaciclib + 100 mg/kg/d astragaloside IV, and abemaciclib + 150 mg/kg/d astragaloside IV. Abemaciclib and astragaloside IV were orally administrated, and astragaloside IV was pre-administrated for 7 d in the co-administrated groups. The pharmacokinetics and transport of abemaciclib were assessed in the absence or presence of astragaloside IV. In mechanism, the activity of CYP3A4 was estimated in human liver microsomes in the presence of astragaloside IV. RESULTS: Astragaloside IV significantly increased the Cmax (from 991.5 ± 116.99 up to 2308.5 ± 55.29 µg/L) and AUC (from 24.49 ± 2.86 up to 66.14 ± 1.17 µg/mL × h) and prolonged the t1/2 (from 19.85 ± 4.65 up to 66.17 ± 28.73 h) of abemaciclib, and the effect was enhanced with the increasing astragaloside IV concentration. Astragaloside IV also suppressed the transport of abemaciclib with the efflux ratio decreasing to 1.35. Astragaloside IV suppressed the activity of CYP3A4 with an IC50 value of 21.78 µM. DISCUSSION AND CONCLUSIONS: The co-administration of abemaciclib and astragaloside IV induced the increasing systemic exposure of abemaciclib through the inhibition of CYP3A4. Further clinical validations could be carried out according to the study design of the present investigation.


Assuntos
Saponinas , Triterpenos , Aminopiridinas , Animais , Benzimidazóis , Citocromo P-450 CYP3A , Humanos , Masculino , Ratos , Ratos Sprague-Dawley
12.
Int J Mol Sci ; 23(19)2022 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-36232615

RESUMO

To study the thermal decomposition behavior of 4,4'-azobis(1,2,4-triazole) (ATRZ), the non-isothermal thermal decomposition kinetics of ATRZ were studied using the thermogravimetric-differential scanning calorimetry (TG-DSC) method. The TG-DSC of ATRZ was analyzed at heating rates of 5, 10, 15, and 20 K·min-1 in an argon atmosphere. The thermal decomposition kinetic parameters at peak temperature (Tp), such as apparent activation energy (Ea) and pre-exponential factor (lgA) of ATRZ, were calculated using the Kissinger, Ozawa, and Satava-Sestak methods. Ea and lgA calculated using the Kissinger, Ozawa, and Satava-Sestak methods are very close, at 780.2 kJ·mol-1/70.5 s-1, 751.1 kJ·mol-1/71.8 s-1, and 762.1 kJ·mol-1/71.8 s-1, respectively. Using a combination of three methods, the reaction mechanism function g(α) of ATRZ was obtained. The results show that the decomposition temperature of ATRZ is about 310 °C, and the decomposition is rapidly exothermic. The pyrolysis path of ATRZ was investigated through a pyrolysis-gas chromatography mass spectrometry (PY-GC/MS) experiment. ATRZ has three different decomposition paths and finally generates N2, HC-N-CH, N≡C-N, and HC=N-C≡N. The laser ignition combustion duration of ATRZ was 0.5033 s and the peak temperature was 1913 °C. The laser ignition combustion duration of ATRZ+CL-20 was 1.0277 s and the peak temperature was 2105 °C. The rapid energy release rate of ATRZ promotes the combustion energy release of CL-20.


Assuntos
Nitrogênio , Pirólise , Argônio , Cinética , Termogravimetria , Triazóis
13.
Phytochemistry ; 204: 113441, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36162460

RESUMO

Six undescribed meleagrin analogues, isomeleagrin, meleagrin F, meleagrin G, methylmeleagrin G, isomethylmeleagrin G and meleagrin H, were isolated from the endophytic fungus Penicillium commune, which was obtained from the fresh leaves of a toxic medicinal plant, Tylophora ovata. The structures of these analogues were elucidated through extensive spectroscopic data analysis, and their absolute configurations were characterized by calculated electronic circular dichroism (ECD). Structurally, meleagrin F features an undescribed skeleton with an aniline moiety, which is linked to meleagrin through a C-C bond at C8-C26. Connecting N19-C3' through the C-N bond in meleagrin G, methylmeleagrin G, isomethylmeleagrin G and meleagrin H was rare for amino acid condensation. The cytotoxicity activity of these undescribed compounds was evaluated, and isomeleagrin exhibited a selective cytotoxicity activity against HGC27 cells with an IC50 value of 2.01 µM.

14.
J Asian Nat Prod Res ; 24(12): 1128-1133, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36036174

RESUMO

Two new sydowic acid derivatives, a pair of enantiomers, involving (+)-sydowiccal (1a) and (-)-sydowiccal (1b), a new sulfonyl metabolite of 2-methoxy-5-methyl-3-(methylsulfonyl)phenol (2), as well as three known sydowic acid derivatives, were isolated from Aspergillus sydowii, an endophytic fungus of Rhododendron mole. The structures of these new compounds were elucidated by analyzing their NMR and HRESIMS data, and the absolute configurations of enantiomers were determined on the basis of the CD spectrum. Three new metabolites showed weak anti-inflammation on nitric oxide (NO) production in LPS-induced RAW 264.7 cells.


Assuntos
Aspergillus , Fungos , Camundongos , Animais , Estrutura Molecular , Aspergillus/química , Células RAW 264.7
15.
Hum Exp Toxicol ; 41: 9603271221116276, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36000339

RESUMO

BACKGROUND: Post-operative recognition dysfunction (POCD) is a kind of central nervous system complication that appears after operative anesthesia. Recent studies on the mechanism of long non-coding RNA (lncRNA) in neurodegenerative diseases are abundant. AIMS: The study aimed to explore the expression pattern and role of lncRNA OIP5-AS1 in POCD and to investigate its underlying mechanism in old rats. METHODS: The old rats were exposed to isoflurane to mimic the POCD in the elderly, and their cognitive function was tested via Morris water maze (MWM) test. Enzyme linked immunosorbent assay was applied for the concentration detection of inflammation and oxidative stress-related factors. Luciferase reporter assay was done for the target gene analysis. RESULTS: Downregulation of OIP5-AS1 was accompanied by isoflurane treatment in rats, overexpression of OIP5-AS1 induced the rats to spend more time in the target quadrant, and shorten escape latency time. OIP5-AS1 inhibited the release of TNF-α, IL-6 and IL-1ß, GSH and superoxide dismutase, decreased the activation of caspase-3, but promoted malondialdehyde release. miR-186-5p was a target miRNA of OIP5-AS1, and exhibited high expression in rats after isoflurane exposure. miR-186-5p can abolish the beneficial role of OIP5-AS1 against cognitive impairment, inflammatory response, oxidative stress and neuron apoptosis. CONCLUSION: OIP5-AS1 plays a neuroprotective role in elderly POCD rats through sponging miR-186-5p, and it is related to OIP5-AS1/miR-186-5p mediated inflammatory response, oxidative stress and neuron apoptosis.


Assuntos
Disfunção Cognitiva , Isoflurano , MicroRNAs , RNA Longo não Codificante , Animais , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/genética , Regulação para Baixo , Isoflurano/toxicidade , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Ratos
16.
J Asian Nat Prod Res ; 24(5): 468-482, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35118925

RESUMO

Six new secondary metabolites, including two new nor-triterpenes (1 and 2), one new sesquiterpene (4), two new α-pyrone derivatives (6 and 7), and one new natural product (5) along with two known compounds (3 and 8) were isolated from an endophytic fungus Colletotrichum gloeosporioides obtained from a toxic medicinal plant Tylophora ovata. Their structures were elucidated by spectroscopic data analyses, while their absolute configurations were determined by CD and X-ray diffraction analyses. The in vitro anti-inflammatory activities of these compounds were evaluated.


Assuntos
Colletotrichum , Plantas Medicinais , Colletotrichum/química , Colletotrichum/metabolismo , Endófitos/química , Estrutura Molecular , Tylophora
17.
J Nat Prod ; 85(1): 148-161, 2022 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-35029398

RESUMO

Twelve new dimeric tetrahydroxanthones, muyocoxanthones A-L (1-12), were isolated from the endophytic fungus, Muyocopron laterale. Their structures were characterized on the basis of the interpretation of NMR and HRESIMS data. The absolute configurations of 1-10 and 12 were unambiguously determined by ECD spectrum data and single-crystal X-ray diffraction analysis. Compounds 2, 6, and 11 showed inhibitory activity against the LPS-induced production of nitric oxide (NO) in RAW 264.7 cells with IC50 values of 5.2, 1.3, and 5.1 µM, respectively.


Assuntos
Anti-Inflamatórios/farmacologia , Ascomicetos/química , Xantonas/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Cristalografia por Raios X/métodos , Dimerização , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Óxido Nítrico/biossíntese , Espectroscopia de Prótons por Ressonância Magnética , Células RAW 264.7 , Espectrometria de Massas por Ionização por Electrospray/métodos
18.
Front Neurosci ; 14: 579469, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33192265

RESUMO

Brain-computer interfaces (BCIs) based on rapid serial visual presentation (RSVP) have been widely used to categorize target and non-target images. However, it is still a challenge to detect single-trial event related potentials (ERPs) from electroencephalography (EEG) signals. Besides, the variability of EEG signal over time may cause difficulties of calibration in long-term system use. Recently, collaborative BCIs have been proposed to improve the overall BCI performance by fusing brain activities acquired from multiple subjects. For both individual and collaborative BCIs, feature extraction and classification algorithms that can be transferred across sessions can significantly facilitate system calibration. Although open datasets are highly efficient for developing algorithms, currently there is still a lack of datasets for a collaborative RSVP-based BCI. This paper presents a cross-session EEG dataset of a collaborative RSVP-based BCI system from 14 subjects, who were divided into seven groups. In collaborative BCI experiments, two subjects did the same target image detection tasks synchronously. All subjects participated in the same experiment twice with an average interval of ∼23 days. The results in data evaluation indicate that adequate signal processing algorithms can greatly enhance the cross-session BCI performance in both individual and collaborative conditions. Besides, compared with individual BCIs, the collaborative methods that fuse information from multiple subjects obtain significantly improved BCI performance. This dataset can be used for developing more efficient algorithms to enhance performance and practicality of a collaborative RSVP-based BCI system.

19.
Zhongguo Zhong Yao Za Zhi ; 45(6): 1368-1373, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32281350

RESUMO

Eight compounds,(R)-2-[5-(methoxycarbonyl)-4-methyl-6-oxo-3,6-dihydro-2H-pyran-2-yl]acetic acid(1),(3S,4R)-3,4-dihydro-3,4-epoxy-5-hydroxynaphthalen-1(2H)-one(2),(-)-mitorubrinol(3),(-)-mitorubrin(4),(±)-asperlone A(5), terreusinone(6), verrucisidinol(7) and cerebroside C(8) were isolated from the endophytic fungus Talaromyces purpurogenus by using various column chromatographic techniques. Their structures were identified by NMR, MS, CD and optical rotation. Compounds 1 and 2 were new compounds. Their anti-diabetic activities in vitro were evaluated, and compound 1 showed moderate inhibitory activity toward XOD at 10 µmol·L~(-1) with the inhibition rate of 69.9%.


Assuntos
Talaromyces/química , Tylophora/microbiologia , Endófitos/química , Hipoglicemiantes/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Metabolismo Secundário , Xantina Oxidase/antagonistas & inibidores
20.
RSC Adv ; 10(16): 9736-9744, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35497245

RESUMO

It is well known that transition metal oxides (TMOs) have attracted extensive attention as promising anodes for next-generation lithium ion batteries (LIBs) owing to their low cost and high theoretical capacities. However, the huge volume changes upon lithiation/delithiation cycling gradually cause drastic particle pulverization in the electrodes, thus leading to fast capacity fading and limiting their practical applications. High-entropy oxides with enhanced electronic conductivity and multiple electrochemically active elements display stepwise lithium storage behaviors, thus efficiently alleviating the volume change induced electrode pulverization problem. Herein, we report the synthesis of a new kind of spinel (Mg0.2Ti0.2Zn0.2Cu0.2Fe0.2)3O4 material via a facile one-step solid state reaction method and subsequent high-energy ball-milling. When used as anodes for LIBs, the submicrometer-sized (Mg0.2Ti0.2Zn0.2Cu0.2Fe0.2)3O4 particles exhibit superior lithium storage properties, delivering a large reversible capacity of 504 mA h g-1 at a current density of 100 mA g-1 after 300 cycles, and notably an exceptional rate capacity of 272 mA h g-1 at 2000 mA g-1. Our work highlights that rational design of high-entropy oxides with different electrochemically active elements and novel structures might be a useful strategy for exploring high-performance LIB anode materials in next-generation energy storage devices.

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