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1.
J Hazard Mater ; 465: 133186, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38086300

RESUMEN

A sensitive, robust, and highly efficient analytical methodology involving solid phase extraction coupled to ultra-high performance liquid chromatography tandem mass spectrometry was successfully established to detect 13 monoalkyl phthalate esters (MPAEs) in aquatic organisms and seawater. After the organisms were preprocessed using enzymatic deconjugation with ß-glucuronidase, extraction, purification, and qualitative and quantitative optimization procedures were performed. Under optimal conditions, the limits of detection varied from 0.07 to 0.88 µg/kg (wet weight) and 0.04-1.96 ng/L in organisms and seawater, respectively. Collectively, MPAEs achieved acceptable recovery values (91.0-102.7%) with relative standard deviations less than 10.4% and matrix effects ranging from 0.93 to 1.07 in the above matrix. Furthermore, MPAEs and phthalate esters were detected by the developed methodology and gas chromatography-triple quadrupole tandem mass spectrometer in practical samples, respectively. Mono-n-butyl phthalate and mono-iso-butyl phthalate were the most predominant congeners, accounting for 24.8-35.2% in aquatic organisms and seawater. Comprehensive health and ecological risks were higher after the MPAEs were incorporated than when phthalate esters were considered separately, and greater than their risk threshold. Therefore, the risks caused by substances and their metabolites in multiple media, with analogous structure-activity relationships, should be considered to ensure the safety of aquatic organisms and consumers.


Asunto(s)
Ésteres , Ácidos Ftálicos , Cromatografía de Gases y Espectrometría de Masas , Ésteres/análisis , Organismos Acuáticos , Ácidos Ftálicos/análisis , Agua de Mar/química , Extracción en Fase Sólida , Medición de Riesgo
2.
Nano Lett ; 23(23): 10739-10747, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-37987831

RESUMEN

Transferring the high strength of individual carbon nanotubes (CNTs) to macroscopic fibers is still a major technical challenge. In this study, CNT fibers are wound from a hollow cylindrical assembly. In particular, atomized catalytic pyrolysis is utilized to produce the fiber and control its purity. The pristine fiber is then continuously prestrained to have a highly aligned structure for subsequent full densification. Experimental measurements show that the final fiber possesses a high tensile strength (8.0 GPa), specific strength (5.54 N tex-1 (tex: the weight (g) of a fiber of 1 km long)), Young's modulus (350 GPa), and elongation at break (4%). Such an excellent combination is superior to that of any other existing fiber and attributed to the efficient stress transfer among the highly aligned and packed CNTs. Our study provides a new strategy involving atomized catalysis for developing superstrong CNT assemblies such as fibers and films for practical applications.

3.
Sci Total Environ ; 867: 161549, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-36640892

RESUMEN

Due to the rising usage of plastics, plastic debris are present throughout marine ecosystems and detrimentally affects marine biota. Additionally, plastics likely result in elusive toxicity effects due to addition of plasticizers. The aim of the present study was to reveal the potential effects and mechanism of microplastics (MPs), di-(2-ethylhexyl) phthalate (DEHP) and copollution of MPs and DEHP (MPs-DEHP) on Peneaus vannamei (P. vannamei) juveniles regarding oxidative stress, transcriptomics and metabolomics. MPs, DEHP and MPs-DEHP significantly induced the activities of superoxide dismutase (SOD) and catalase (CAT); MPs and DEHP have an antagonistic effect for malondialdehyde (MDA); suggesting that disorders of the antioxidant defence systems. 13, 133 and 58 differentially expressed genes and 21, 82 and 39 differentially expressed metabolites were responsible for the distinction of MPs, DEHP and MPs-DEHP groups, respectively. The combination of transcriptomic and metabolomic analyses showed that MPs, DEHP and MPs-DEHP exposure disturbed amino acid and lipid metabolism, and further induced inflammatory responses and dysfunction of purine metabolism. Furthermore, the presence of MPs might alleviate the biotoxicity of DEHP in P. vannamei. These findings provide new insights into the single and combined toxicological effects of MPs and additives for marine biota.


Asunto(s)
Dietilhexil Ftalato , Ácidos Ftálicos , Dietilhexil Ftalato/toxicidad , Dietilhexil Ftalato/metabolismo , Plásticos/toxicidad , Microplásticos , Transcriptoma , Ecosistema , Plastificantes/toxicidad
4.
Nat Prod Rep ; 39(11): 2096-2131, 2022 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-36106498

RESUMEN

Covering: up to December 2021Picrotoxane sesquiterpenoids are a special category of natural products known to have a picrotoxane skeleton and are characterised by a highly oxidised cis-hydrindene core, lactone rings, and epoxide functionalities. Ever since the first picrotoxane was isolated from Menispermum cocculus in the early 19th century, these compounds have long attracted the attention of natural product chemists, synthetic chemists, and pharmacologists for their particular structures and powerful biological activities. This review extensively summarizes a total of 132 naturally occurring picrotoxane sesquiterpenoids, taking into account their distributions, structural classifications, chemical and bio-synthetic researches, and bioactivities. It provides a comprehensive and in-depth perspective for further investigation on picrotoxane sesquiterpenoids.


Asunto(s)
Productos Biológicos , Sesquiterpenos , Sesquiterpenos/farmacología , Sesquiterpenos/química , Productos Biológicos/farmacología , Productos Biológicos/química , Lactonas
5.
J Clin Transl Hepatol ; 10(2): 230-237, 2022 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-35528974

RESUMEN

Background and Aims: We compared lung function parameters in nonalcoholic fatty liver disease (NAFLD) and metabolic dysfunction-associated fatty liver disease (MAFLD), and examined the association between lung function parameters and fibrosis severity in MAFLD. Methods: In this cross-sectional study, we randomly recruited 2,543 middle-aged individuals from 25 communities across four cities in China during 2016 and 2020. All participants received a health check-up including measurement of anthropometric parameters, biochemical variables, liver ultrasonography, and spirometry. The severity of liver disease was assessed by the fibrosis (FIB)-4 score. Results: The prevalence of MAFLD was 20.4% (n=519) and that of NAFLD was 18.4% (n=469). After adjusting for age, sex, adiposity measures, smoking status, and significant alcohol intake, subjects with MAFLD had a significantly lower predicted forced vital capacity (FVC, 88.27±17.60% vs. 90.82±16.85%, p<0.05) and lower 1 s forced expiratory volume (FEV1, 79.89±17.34 vs. 83.02±16.66%, p<0.05) than those with NAFLD. MAFLD with an increased FIB-4 score was significantly associated with decreased lung function. For each 1-point increase in FIB-4, FVC was diminished by 0.507 (95% CI: -0.840, -0.173, p=0.003), and FEV1 was diminished by 0.439 (95% CI: -0.739, -0.140, p=0.004). The results remained unchanged when the statistical analyses was performed separately for men and women. Conclusions: MAFLD was significantly associated with a greater impairment of lung function parameters than NAFLD.

6.
J Nat Prod ; 85(4): 878-887, 2022 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-35293744

RESUMEN

Eight new aspulvinone analogues, aspulvins A-H (1-8) and aspulvinones D, M, O, and R (9-12), were isolated from cultures of the endophytic fungus Cladosporium sp. 7951. Detailed spectroscopic analyses were conducted to determine the structures of the new compounds. All isolates displayed different degrees of inhibitory activity against the severe acute respiratory syndrome coronavirus 2 main protease (SARS-CoV-2 Mpro) at 10 µM. Notably, compounds 9, 10, and 12 showed potential SARS-CoV-2 Mpro inhibition with IC50 values of 10.3 ± 0.6, 9.4 ± 0.6, and 7.7 ± 0.6 µM, respectively. For all compounds except 3 and 4, the anti-inflammatory activity occurred by inhibiting the release of lactate dehydrogenase (LDH) with IC50 values ranging from 0.7 to 7.4 µM. Compound 10 showed the most potent anti-inflammatory activity by inhibiting Casp-1 cleavage, IL-1ß maturation, NLRP3 inflammasome activation, and pyroptosis. The findings reveal that the aspulvinone analogues 9, 10, and 12 could be promising candidates for coronavirus disease 2019 (COVID-19) treatment as they inhibit SARS-CoV-2 infection and reduce inflammatory reactions caused by SARS-CoV-2.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , SARS-CoV-2 , Antiinflamatorios/farmacología , Antivirales/química , Cladosporium , Humanos
7.
Fitoterapia ; 157: 105139, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35108573

RESUMEN

A phytochemical investigation was conducted on Euphorbia helioscopia, resulting in the isolation of thirteen compounds, including nine undescribed diterpenoids, Euphzycopias A - I (1-9), of which the skeletons of compounds 1-4 were found in E. helioscopia L. Compounds 1-3 had 5/7/6 cyclic systems, while compound 4 had a 4/11 polycyclic system with a 4,7-cyclic ether between C-4 and C-7. The anti-inflammasome test using the isolated compounds (1-6, 8-13) showed that the diterpenes from E. helioscopia L. had a strong inhibitory effect on NLRP3 inflammasomes with IC50 values of 3.34-14.92 µM.


Asunto(s)
Diterpenos/farmacología , Euphorbia/química , Inflamasomas/farmacología , Diterpenos/química , Diterpenos/aislamiento & purificación , Humanos , Inflamasomas/química , Inflamasomas/aislamiento & purificación , Concentración 50 Inhibidora , Espectroscopía de Resonancia Magnética , Estructura Molecular , Proteína con Dominio Pirina 3 de la Familia NLR/antagonistas & inhibidores , Rotación Óptica , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Espectrofotometría Infrarroja
8.
Nat Prod Res ; 36(1): 193-199, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32498562

RESUMEN

Two new triterpenoid-chromone hybrids, cimitriteromones H (1) and I (2), along with two known analogues (3, 4) were isolated from the phytochemical research on the n-butyl alcohol extracts of Actaea cimicifuga rhizomes. The new compounds were elucidated by spectroscopic experiments and chemical method. The cytotoxic activities of the isolated compounds were tested on A-549/Taxol cell line. Cimitriteromone I (2) showed cytotoxicity with IC50 value of 27.14 ± 1.38 µM comparable to positive control group cisplatin (IC50 value of 25.80 ± 1.15 µM).


Asunto(s)
Actaea , Cimicifuga , Triterpenos , Cromonas/farmacología , Rizoma , Triterpenos/farmacología
9.
Molecules ; 26(16)2021 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-34443501

RESUMEN

Nuclear magnetic resonance (NMR) spectroscopy was used for the qualitative and quantitative analysis of aqueous extracts of unroasted and roasted coffee silverskin (CS). Twenty compounds were identified from 1D and 2D NMR spectra, including caffeine, chlorogenic acid (CGA), trigonelline, fructose, glucose, sucrose, etc. For the first time, the presence of trigonelline was detected in CS. Results of the quantitative analysis showed that the total amount of the main components after roasting was reduced by 45.6% compared with values before roasting. Sugars in the water extracts were the main components in CS, and fructose was the most abundant sugar, its relative content accounting for 38.7% and 38.4% in unroasted and roasted CS, respectively. Moreover, 1D NMR combined with 2D NMR technology shows application prospects in the rapid, non-destructive detection of CS. In addition, it was observed by optical microscopy and scanning electron microscopy (SEM) that the morphology of CS changed obviously before and after roasting.


Asunto(s)
Café/anatomía & histología , Café/química , Alcaloides/análisis , Alcaloides/química , Hidroxibenzoatos/análisis , Extractos Vegetales/análisis , Espectroscopía de Protones por Resonancia Magnética , Azúcares/química
10.
J Agric Food Chem ; 69(8): 2438-2443, 2021 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-33591736

RESUMEN

The seed oil of Prinsepia utilis is extensively used as an edible oil by the nationalities of Naxi, Tibetan, and Mosuo in China, which is particularly good for beauty care and has a health protection function. A large amount of industrial waste is thrown away during the production process of seed oil. Therefore, to recover bioactive compounds from the oil residue of P. utilis is environmentally friendly and economically important. For this purpose, the chemical constituents of the P. utilis oil residue were investigated in our research, and five new compounds, prinsepicyanosides F-I (1-4) and prinamoside A (5), together with 16 known compounds (6-21) were isolated. The structures of the new compounds (1-5) were unambiguously confirmed by extensive spectroscopic techniques. Preliminary in vitro pharmacological studies showed that the hydroxynitrile glucosides (3, 9, and 10) exhibited weak α-glucosidase inhibitory activity. To a certain extent, our research provides some evidence for the pharmacological function of γ-hydroxynitrile glucosides and proposes new ideas for recycling of the oil residue of P. utilis.


Asunto(s)
Glucósidos , Rosaceae , China , Semillas
11.
Phytochemistry ; 184: 112661, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33454615

RESUMEN

Nine undescribed limonoids, 18(13 â†’ 14)-abeo-15ß,21-dihydroxy-24,25,26,27-tetranor-3,7-dioxoapotirucalla-1,9(11),13(17),20(22)-tetraen-23,21-olide (Toonaone A), 21-hydroxy-24,25,26,27-tetranor-3,7,15-trioxoapotirucalla-1,9(11),20(22)-trien-23,21-olide (Toonaone B), 7α,21-dihydroxy-12α-isobutyryl-24,25,26,27-tetranor-3,15-dioxoapotirucalla-1,20(22)-dien-23,21-olide (Toonaone C), 7,8-seco-7-methyl ester-11ß-acetoxy-14ß,15ß-epoxy-21-hydroxy-24,25,26,27-tetranor-3-oxoapotirucalla-1,8(30),20(22)-trien-23,21-olide (Toonaone D), 7,8-seco-7-methyl ester-11ß-acetoxy-14ß,15ß-epoxy-23-hydroxy-24,25,26,27-tetranor-3-oxoapotirucalla-1,8(30),20(22)-trien-21,23-olide (Toonaone E), 7,8-seco-7-methyl ester-11ß-acetoxy-14ß,15ß-epoxy-6ß,21-dihydroxy-24,25,26,27-tetranor-3-oxoapotirucalla-1,8(30),20(22)-trien-23,21-olide (Toonaone F), 7,8-seco-7-methyl ester-14ß,15ß-epoxy-8α,21-dihydroxy-24,25,26,27-tetranor-3-oxoapotirucalla-1,20(22)-dien-23,21-olide (Toonaone G), 7,8-seco-7-methyl ester-14ß,15ß-epoxy-6ß,8α,21-trihydroxy-24,25,26,27-tetranor-3-oxoapotirucalla-1,20(22)-dien-23,21-olide (Toonaone H), 7,8-seco-7-methyl ester-14ß,15ß-epoxy-6ß,8α,21-trihydroxy-24,25,26,27-tetranor-3-oxoapotirucalla-1,20(22)-dien-21,23-diimide (Toonaone I), and five known analogues were isolated from the twigs of Toona ciliata M. Roem. (Meliaceae). Toonaone A possesses the first rare 18(13 â†’ 14)-abeo-limonoid skeleton reported from the genus Toona. Their structures were elucidated using spectroscopic data analyses and quantum chemistry calculations. Biological evaluation showed that toonaone C, toonaone D, toonaone G, toonaciliatavarin F, and toonaciliatavarin G exhibited significant anti-NLRP3 inflammasome activity with IC50 values ranging from 3.74 to 18.7 µM. GMDMD, IL-1ß, and caspase-1 analyses suggested that toonaone D inhibited NLRP3 inflammasome activation and blocked macrophage pyroptosis.


Asunto(s)
Cilióforos , Limoninas , Inflamasomas , Limoninas/farmacología , Estructura Molecular , Proteína con Dominio Pirina 3 de la Familia NLR , Toona
12.
RSC Adv ; 11(12): 6655-6661, 2021 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-35423176

RESUMEN

Carbon nanotubes (CNTs) have been considered as promising electrode materials for energy storage devices, especially flexible electronics owing to their excellent electrical, physicochemical and mechanical properties. However, the severe aggregation between CNTs significantly reduces the electrochemically active surface areas and thus degrades the electrochemical properties. In this study, we demonstrate a facile layer-by-layer strategy toward preparing a CNT/hollow carbon nanocage (HCNC) hybrid film. Through electrochemically removing the impurities in CNT films and optimizing the concentrations of HCNC, the hybrid film exhibits a high specific capacitance of 183.7 F g-1 at 10 mV s-1 and good cycling stability of 85% retention after 5000 cycles at 1 A g-1. Our study provides potential scale-up synthesis of free-standing CNT electrode materials for high-performance supercapacitors.

13.
Chem Biodivers ; 17(12): e2000798, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33135326

RESUMEN

Four new diterpenoids, rubellawus A-D (1-4), along with three known compounds, were isolated and identified from the flowers of Callicarpa rubella. Their structures were elucidated by various spectroscopic analysis. All the compounds were screened for their anti-inflammatory activity and 14α-hydroxyisopimaric acid and isopimaric acid showed significant NLRP3 inflammasome inhibitory activity with IC50 values of 7.02 and 3.99 µM.


Asunto(s)
Callicarpa/química , Diterpenos/aislamiento & purificación , Diterpenos/farmacología , Inflamasomas/antagonistas & inhibidores , Proteína con Dominio Pirina 3 de la Familia NLR/antagonistas & inhibidores , Animales , Línea Celular , Diterpenos/química , Análisis Espectral/métodos , Relación Estructura-Actividad
14.
Fitoterapia ; 147: 104774, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33152461

RESUMEN

Nine new diterpenoids, Rubellacrns A - I (1-9), including five isopimaranes (1-4, 9), four pimaranes (5-8), together with five known isopimarane analogues (10-14), were isolated from Callicarpa rubella. The structures of these compounds were unambiguously established by HR-ESIMS and NMR spectroscopic data, the absolute configurations of compounds 5 and 9 were determined by ECD. All the isolated compounds were tested for their anti-inflammatory effects and compounds 2 and 11-14 showed NLRP3-inflammasome inhibitory activity with IC50 values ranging from 7.02 to 14.38 µM.


Asunto(s)
Callicarpa/química , Diterpenos/farmacología , Inflamasomas/antagonistas & inhibidores , Proteína con Dominio Pirina 3 de la Familia NLR/antagonistas & inhibidores , Abietanos , Animales , Línea Celular , China , Diterpenos/aislamiento & purificación , Macrófagos/efectos de los fármacos , Ratones , Estructura Molecular , Fitoquímicos/aislamiento & purificación , Fitoquímicos/farmacología , Hojas de la Planta/química
15.
Bioorg Chem ; 105: 104363, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33075665

RESUMEN

Twenty-four new limonoids, toonaolides A-X (1-24), characterized with an α,ß-unsaturated-γ-lactone A-ring were isolated from the twigs of Toona ciliata. Their structures and absolute configurations were elucidated by spectroscopic data, X-ray diffraction crystallography, and quantum chemistry calculations. Most of the isolated compounds (except 9, 18, and 24 which possessed the maleimide ring) featured the rare 21-hydroxybutenolide or 23-hydroxybutenolide moieties. In particular, compound 1 has an unprecedented limonoid architecture with 6/6 cis-fused A/B ring system and 2 has an unusual tetrahydrofuran ring B skeleton, featuring a 7/5/6/5 ring system. The biological evaluation showed that compounds 9, 11, 12, 14, and 18 exhibited significantly anti-NLRP3 inflammasome activity with IC50 values ranging from 3.2 to 9.7 µM. Analysis of IL-1ß and caspase-1 expression revealed that compounds 11 and 12 are selective inhibitors of NLRP3 inflammasome, which could ameliorate cell pyroptosis by blocking NLRP3 inflammasome activation.


Asunto(s)
Inflamasomas/antagonistas & inhibidores , Limoninas/farmacología , Proteína con Dominio Pirina 3 de la Familia NLR/antagonistas & inhibidores , Extractos Vegetales/farmacología , Toona/química , Teoría Funcional de la Densidad , Relación Dosis-Respuesta a Droga , Humanos , Inflamasomas/metabolismo , Limoninas/química , Limoninas/aislamiento & purificación , Estructura Molecular , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Relación Estructura-Actividad
16.
Org Lett ; 22(20): 7820-7824, 2020 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-32991190

RESUMEN

Euphopias A-C (1-3), three rearranged jatrophane-type diterpenoids with tricyclo[8.3.0.02,7]tridecane (1 and 2) and tetracyclo[11.3.0.02,10.03,7]hexadecane (3) cores, were isolated from Euphorbia helioscopia. Comprehensive spectroscopic analyses, quantum-chemical calculations, and X-ray diffractions were used to identify their structures. Compounds 1-3 could significantly inhibit NLRP3 inflammasome activation and block NLRP3 inflammasome-induced pyroptosis. Additionally, a mechanistic study revealed that 2 could ameliorate mitochondria damage, thereby interrupting NLRP3 inflammasome activation.


Asunto(s)
Diterpenos/farmacología , Euphorbia/química , Proteína con Dominio Pirina 3 de la Familia NLR/antagonistas & inhibidores , Alcanos/química , Diterpenos/química , Diterpenos/aislamiento & purificación , Estructura Molecular , Proteína con Dominio Pirina 3 de la Familia NLR/química
17.
Bioorg Chem ; 100: 103871, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32344184

RESUMEN

Ganoderma resinaceum is a multi-purpose herbal medicine that is homologous to functional food that has long been used for enhancing health and treating chronic hepatopathy in Traditional Chinese Medicine. In a search program to discover the key bioactive composition of G. resinaceum, sixteen new lanostane-type triterpenoids (1-16), and twenty known analogues (17-36) were isolated from the fruiting bodies of G. resinaceum. Spectroscopic analyses and X-ray crystallography were used to determine the new structures. Furthermore, the spectroscopic properties of 15ß-hydroxy-4,4,14α- trimethyl-3,7,11,20-tetraoxo-5α-pregn-8-ene (15) and 15α-hydroxy-4,4,14α-trimethyl- 3,7,11,20-tetraoxo-5α-pregn-8-ene (34) indicated a potential structural misassignment of their analogues, lucidone E and lucidone H, reported previously. To probe this hypothesis, ROESY experiments and single-crystal X-ray diffraction analysis were conducted. These results undoubtedly reassigned the structure of lucidone E and lucidone H. Biological evaluation of the selected compounds disclosed that compounds 3, 4, 7/21, 11, 12, 13/14, 17, 18, 24/25, 27, 30, 31, and 35 had significant hepatoprotective activities, due to their remarkable in vitro inhibitory activities against the increase of ALT and AST levels in HepG2 cells induced by H2O2.


Asunto(s)
Ganoderma/química , Hígado/efectos de los fármacos , Sustancias Protectoras/química , Sustancias Protectoras/farmacología , Triterpenos/química , Triterpenos/farmacología , Cristalografía por Rayos X , Células Hep G2 , Humanos , Peróxido de Hidrógeno/metabolismo , Hígado/citología , Hígado/enzimología , Hígado/metabolismo , Modelos Moleculares , Estrés Oxidativo/efectos de los fármacos , Sustancias Protectoras/aislamiento & purificación , Triterpenos/aislamiento & purificación
18.
ACS Appl Mater Interfaces ; 12(14): 16762-16771, 2020 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-32216324

RESUMEN

Antireflective (AR) materials are required to possess high optical antireflection and mechanical stability for their practical applications in optical, opto-electronic, and electron-optical devices. However, the AR materials developed so far can hardly meet these requirements. Here, we report the construction of a highly porous and sponge-like material based on carbon nanotubes (CNTs). This is achieved by continuous winding of a hollow cylindrical CNT assembly and subsequent modification with amorphous carbon (AC). The resultant material is shown to have very low optical reflectance at the visible and infra-red wavelengths over a wide range of incident angles and undergoes little degradation even after long-lasting compressive cycling between 0 and 90% strains or a large change of environmental temperature from -196 to 300 °C. Besides, the AR sponge material can recover fast after bending, stretching, and compression from high elastic strains. Such an excellent combination of broadband and omnidirectional antireflection, mechanical stability, and elastic flexibility results from the strong light absorption by the highly porous CNT structures strengthened by AC deposition on CNT surfaces and junctions, and the new AR material has potential applications in the renewable energy and military fields.

19.
Bioorg Chem ; 98: 103723, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32171984

RESUMEN

Six previously undescribed benzolactone constituents, ganodumones A-F (1-6), a new type of Ganoderma meroterpenoids (GMs) fused with 1,2,3,4,5-pentasubstituted phenyl and 1',2'-dioxy-3'-methyl-pentyl chain were isolated from the fruiting bodies of Ganoderma lucidum. Their structures were determined by spectroscopic analysis, X-ray crystal diffraction, and ECD computational methods. Meanwhile, bioactive evaluation showed that compounds 3 and 5 have antibacterial activities against Microsporum gypseum with MIC90 56.86 ± 3.98 and 18.48 ± 0.47 µg/mL, respectively.


Asunto(s)
Antifúngicos/farmacología , Arthrodermataceae/efectos de los fármacos , Ganoderma/química , Lactonas/farmacología , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Cristalografía por Rayos X , Relación Dosis-Respuesta a Droga , Cuerpos Fructíferos de los Hongos/química , Lactonas/química , Lactonas/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Modelos Moleculares , Conformación Molecular , Relación Estructura-Actividad
20.
Phytochemistry ; 173: 112256, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32062196

RESUMEN

Ganoderma lucidum is one of the most famous medicinal fungi and is traditional Chinese medicine with various biological activities in Asian countries. To clarify its pharmacodynamic material basis, 15 lanostane triterpenoidswere obtained from the fruiting bodies of G. lucidum, including 8 previously undescribed lanostanoids. Their structures, including absolute configuration, were established based on ultraviolet, infrared, high-resolution electrospray ionisation mass spectrometry, 1D and 2D nuclear magnetic resonance, and X-ray crystallographic analysis. Ganoluciduone A was an unusual octonorlanostane, which was isolated from Ganoderma for the first time. In addition, the anti-inflammatory activities of all isolates were evaluated by observing their inhibitory effects on nitric oxide production in RAW264.7 cells activated by a lipopolysaccharide. Ganoluciduone B exhibited moderate inhibitory activity on nitric oxide production, with an inhibition rate of 45.5% at a concentration of 12.5 µM.


Asunto(s)
Ganoderma , Reishi , Triterpenos , Animales , Antiinflamatorios , Asia , Cuerpos Fructíferos de los Hongos , Ratones , Estructura Molecular
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