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1.
Opt Lett ; 46(7): 1592-1595, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33793495

RESUMEN

Lack of tunability impedes the wide application of optomechanical systems; however, little research exists on mechanical frequency tuning. Herein, ultra-fine low-loss dynamical mechanical frequency tuning is achieved by compressing a microsphere along the axial direction. The tuning resolution reaches approximately 4% of the mechanical linewidth, and the variation range of the mechanical quality factor (Qm) is within 2.9% of the untouched Qm. The roles of geometric deformation, spring effect, and stiffness were also evaluated through simulation and experimental analysis. Furthermore, sine function modulation was displayed, with a Pearson coefficient exceeding 99.3%, to achieve arbitrary-function mechanical resonance tuning. This method paves the way for scalable optomechanical applications, such as mechanical vibration synchronization or optomechanics-based optical wavelength conversion.

2.
Polymers (Basel) ; 12(5)2020 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-32353941

RESUMEN

The possibility of exchange reactions and thermal self-healing in blends of thermoplastic polyurethane (TPU) and phenoxy resin was investigated herein. The analyses were based on characterization obtained via differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), dynamic mechanical analysis (DMA), and tensile test. A new phenoxy resin was synthesized from eugenol, and blends with different types of TPU were prepared to investigate the exchange reaction, thermal self-healing, and mechanical properties. The influence of phenoxy resin content on the mechanical behavior and healing efficiency was studied. Improvement of storage modulus owing to the increase of phenoxy resin content was observed. Results suggest that the exchange reaction between phenoxy- and ester-type TPU occurred during thermal treatment. However, little exchange occurred between phenoxy resin and ether-type TPU. Specifically, only ester-type TPU exhibited a significant exchange reaction in the phenoxy resin blend. Furthermore, in the presence of a catalyst (e.g., zinc acetate), the exchange reaction readily occurred, and the healing efficiency improved by the addition of the catalyst and increase in the phenoxy content.

3.
Zootaxa ; 4661(1): zootaxa.4661.1.8, 2019 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-31716722

RESUMEN

Larvae of a gall midge were found feeding on the fungal rust Maravalia pterocarpi (Pucciniomycetes: Pucciniales: Chaconiaceae) infesting the economically important sua tree Dalbergia tonkinensis (Fabaceae) on Hainan Island, China. The adults, pupae and larvae were collected, their morphology was studied and a segment of the Cytochrome Oxidase unit I (COI) mitochondrial gene was sequenced. The gall midge proved to be a species new to science that belongs to the genus Mycodiplosis (Diptera: Cecdiomyiidae). Comparison of the sequence to published Cecdiomyiidae sequences revealed that, despite being undescribed and unnamed, it was previously found in east and south-east Asia to feed on several rust species: Puccinia coronata (Pucciniomycetes: Pucciniales: Pucciniaceae) that develops on Lolium multiflorum (Poaceae), Puccinia sp. on Zea mays (Poaceae), Puccinia arachidis on Arachis hypogaea (Fabaceae) and Puccinia allii on Allium fistulosum (Amaryllidaceae). The new species is described and named here Mycodiplosis puccinivora Jiao, Bu Kolesik. It occurs in China, Japan, Thailand, Bangladesh and possibly Malaysia and Australia. In Hainan it has four to five generations per year.


Asunto(s)
Dípteros , Animales , Australia , Bangladesh , China , Japón , Malasia , Tailandia
4.
Polymers (Basel) ; 11(10)2019 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-31615025

RESUMEN

With limited biomass that can be currently utilized as a renewable resource, it is important to develop a method to convert biomass into materials that can replace fossil fuel product. In this paper, eugenol, a bio-based allyl chain-substituted guaiacol, was used to synthesize self-healable copolymers. Eugenol terminated polyurethane prepolymer (ETPU) was synthesized from eugenol and polyurethane prepolymers terminated with isocyanate groups. ETPU contained two allyl groups. Self-healing copolymer networks were obtained by copolymerization of ETPU and styrene monomer via free radical polymerization. Effects of ETPU content on the properties of copolymers were then studied. These copolymers containing ETPU exhibited good thermal stability and mechanical properties. These copolymers showed higher tensile strength and elongation at break than PS. Their maximum tensile strength reached 19 MPa. In addition, these copolymers showed self-healing property at elevated temperature due to the reversible nature of urethane units in ETPU.

5.
Exp Appl Acarol ; 77(4): 527-543, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31062204

RESUMEN

Biological control of spider mites in hot and dry weather is a serious technical issue. A high-temperature adapted strain (HTAS) of the predatory mite Neoseiulus barkeri Hughes was selected from its conventional strain (CS), via long-term heat acclimation and frequent heat hardenings in our previous studies. However, the environment of high temperature is usually associated with enhanced ultraviolet (UV) radiation. In the present study, the physiological effects of UV-B radiation on survival rate and egg damage of N. barkeri were investigated, as well as the activities and expression profiles of antioxidant enzymes to UV-B radiation stress. UV-B radiation had deleterious effects on egg hatchability and survival of N. barkeri. Adults of the HTAS strain were less UV-B resistant than those of the CS strain; they also had lower levels of enzymatic activity of superoxide dismutase (SOD) and catalase against oxidative damage and weaker upregulation of SOD genes. The mRNA expression of three SOD genes of CS adult females immediately increased whereas that of HTAS showed almost no difference under UV-B stress for 1 h. The results showed the HTAS of N. barkeri had lower fitness under UV-B stress compared with the CS of N. barkeri. These results suggested that long-term heat acclimation may exert a profound impact on the developmental physiology of N. barkeri.


Asunto(s)
Proteínas de Artrópodos/genética , Aptitud Genética/efectos de la radiación , Ácaros/efectos de la radiación , Conducta Predatoria/efectos de la radiación , Rayos Ultravioleta/efectos adversos , Adaptación Biológica , Animales , Antioxidantes/metabolismo , Proteínas de Artrópodos/metabolismo , Femenino , Calor , Longevidad/efectos de la radiación , Ácaros/enzimología , Ácaros/genética , Ácaros/fisiología , Óvulo/fisiología , Óvulo/efectos de la radiación , Control Biológico de Vectores , Transcripción Genética/efectos de la radiación
6.
Molecules ; 24(7)2019 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-30959785

RESUMEN

Isosorbide (ISB), a nontoxic bio-based bicyclic diol composed from two fuzed furans, was incorporated into the preparation of flexible polyurethane foams (FPUFs) for use as a cell opener and to impart antioxidant properties to the resulting foam. A novel method for cell opening was designed based on the anticipated reversibility of the urethane linkages formed by ISB with isocyanate. FPUFs containing various amounts of ISB (up to 5 wt%) were successfully prepared without any noticeable deterioration in the appearance and physical properties of the resulting foams. The air permeability of these resulting FPUFs was increased and this could be further improved by thermal treatment at 160 °C. The urethane units based on ISB enabled cell window opening, as anticipated, through the reversible urethane linkage. The ISB-containing FPUFs also demonstrated better antioxidant activity by impeding discoloration. Thus, ISB, a nontoxic, bio-based diol, can be a valuable raw material (or additive) for eco-friendly FPUFs without seriously compromising the physical properties of these FPUFs.


Asunto(s)
Antioxidantes/química , Isosorbida/química , Permeabilidad/efectos de los fármacos , Poliuretanos/química , Antioxidantes/farmacología , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Isocianatos/química , Isocianatos/farmacología , Isosorbida/farmacología , Poliuretanos/farmacología , Uretano/química
7.
Molecules ; 23(12)2018 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-30572638

RESUMEN

Ethyl rosmarinate (RAE) is one of the active constituents from Clinopodium chinense (Benth.) O. Kuntze, which is used for diabetic treatment in Chinese folk medicine. In this study, we investigated the protective effect of RAE on high glucose-induced injury in endothelial cells and explored its underlying mechanisms. Our results showed that both RAE and rosmarinic acid (RA) increased cell viability, decreased the production of reactive oxygen species (ROS), and attenuated high glucose-induced endothelial cells apoptosis in a dose-dependent manner, as evidenced by Hochest staining, Annexin V⁻FITC/PI double staining, and caspase-3 activity. RAE and RA both elevated Bcl-2 expression and reduced Bax expression, according to Western blot. We also found that LY294002 (phosphatidylinositol 3-kinase, or PI3K inhibitor) weakened the protective effect of RAE. In addition, PDTC (nuclear factor-κB, or NF-κB inhibitor) and SP600125 (c-Jun N-terminal kinase, or JNK inhibitor) could inhibit the apoptosis in endothelial cells caused by high glucose. Further, we demonstrated that RAE activated Akt, and the molecular docking analysis predicted that RAE showed more affinity with Akt than RA. Moreover, we found that RAE inhibited the activation of NF-κB and JNK. These results suggested that RAE protected endothelial cells from high glucose-induced apoptosis by alleviating reactive oxygen species (ROS) generation, and regulating the PI3K/Akt/Bcl-2 pathway, the NF-κB pathway, and the JNK pathway. In general, RAE showed greater potency than RA equivalent.


Asunto(s)
Cinamatos/farmacología , Depsidos/farmacología , Células Endoteliales/citología , Glucosa/efectos adversos , Antracenos/farmacología , Apoptosis/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Cromonas/farmacología , Humanos , Simulación del Acoplamiento Molecular , Morfolinas/farmacología , FN-kappa B/metabolismo , Estrés Oxidativo/efectos de los fármacos , Fosfatidilinositol 3-Quinasa/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos , Ácido Rosmarínico
8.
Fitoterapia ; 129: 7-12, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29894737

RESUMEN

Five novel compounds, including four neoclerodane diterpenoids, named ajugacumbins KN (1-4) along with a phytoecdysterone, named ajugacetalsterone E (5), were isolated from the whole herbs of Ajuga decumbens (Labiatae). Their structures were elucidated on the basis of detailed spectroscopic analysis including IR, HRESIMS, CD, 1D and 2D NMR spectroscopic experiments. Compounds 1-5 were evaluated for their cytotoxic activities and the effects on superoxide anion generation and elastase release in FMLP/CB-induced human neutrophils.


Asunto(s)
Ajuga/química , Diterpenos/química , Neutrófilos/efectos de los fármacos , Elastasa Pancreática/metabolismo , Superóxidos/metabolismo , Línea Celular Tumoral , Diterpenos/farmacología , Diterpenos de Tipo Clerodano , Humanos , Estructura Molecular
9.
Biomed Chromatogr ; 31(8)2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28060996

RESUMEN

Peperomin E (PepE), a naturally occurring secolignan isolated from Peperomia dindygulensis, has drawn much attention recently owing to its anticancer and DNA methyltransferase 1 (DNMT1) inhibitory activity. Here, a simple and sensitive ultra-fast liquid chromatography-tandem mass spectrometry method was developed and validated for the determination of PepE in rat plasma for the first time. Samples were prepared by simple protein precipitation. Separation was performed on an XBridge™ C18 column using a mobile phase of acetonitrile and 0.1% (v/v) aqueous formic acid. PepE and the internal standard arctigenin were detected in a positive-ion mode using multiple reaction monitoring of the transitions at m/z 413.2 → 261.0 and 373.2 → 137.2, respectively. The calibration curve for PepE was linear over the range of concentrations of 1.46-6000 ng/mL, with a lower limit of quantitation of 1.46 ng/mL. Both intra- and interday precisions were within 11.05%, and the accuracy ranged from -11.5 to 5.51%. The extraction recovery and matrix effect were within acceptable limits. Stability tests showed that PepE remained stable throughout the analytical procedure. The validated method was then used to analyze the pharmacokinetics of PepE administered to rats orally (12.5 and 25 mg/kg) or intravenously (6.25 and 12.5 mg/kg).


Asunto(s)
Benzodioxoles/sangre , Cromatografía Líquida de Alta Presión/métodos , ADN (Citosina-5-)-Metiltransferasas/antagonistas & inhibidores , Inhibidores Enzimáticos/sangre , Espectrometría de Masas en Tándem/métodos , Administración Oral , Animales , Benzodioxoles/administración & dosificación , Benzodioxoles/análisis , ADN (Citosina-5-)-Metiltransferasa 1 , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/análisis , Límite de Detección , Masculino , Peperomia/química , Ratas , Ratas Sprague-Dawley
10.
Chem Biodivers ; 14(2)2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27447119

RESUMEN

A new 19-oxo-18,19-seco-ursane-type triterpeonoid saponin, laevigin E (8), together with 17 known compounds (1 - 7 and 9 - 18) were isolated from the root bark of Ilex rotunda Thunb. Their structures were determined by various spectroscopic analysis. Among them, compounds 6, 9, 11, and 18 were isolated from this species for the first time, while compounds 10 and 12 were firstly isolated from the family Aquifoliaceae. Biological activity assay showed that all triterpenoids exhibit moderate cytotoxic activities against MCF7, A549, HeLa and LN229 cell lines. The four triterpenoid saponins (3, 4, 6, and 8) exhibit slightly better activities compared to the four triterpenoid sapogenins (1, 2, 5, and 7). Compound 8 showed the best cytotoxicity against A549, HeLa and LN229 cell lines with IC50 of 17.83, 22.58 and 30.98 µm, respectively.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Proliferación Celular/efectos de los fármacos , Ilex/química , Corteza de la Planta/química , Raíces de Plantas/química , Saponinas/farmacología , Triterpenos/farmacología , Células HeLa , Humanos , Estructura Molecular
11.
Fitoterapia ; 115: 92-95, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27601203

RESUMEN

Three novel limonoids, dictangustone G (1), dictangustone H (2), and dictangustone I (3) were isolated from the root bark of Dictamnus angustifolius. Their structures were elucidated on the basis of detailed spectroscopic analysis including UV, IR, HRESIMS, 1D and 2D NMR spectroscopic experiments. Compounds 1-3 were evaluated for their cytotoxic activities using Hela, A549, MCF7, and LN229 cell lines.


Asunto(s)
Antineoplásicos Fitogénicos/química , Dictamnus/química , Limoninas/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Línea Celular Tumoral , Humanos , Limoninas/aislamiento & purificación , Estructura Molecular , Corteza de la Planta/química , Raíces de Plantas/química
12.
Chin J Nat Med ; 14(9): 692-696, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27667515

RESUMEN

In the present study, two new limonoids, 1α, 7α-dihydroxyl-3α-acetoxyl-12α-ethoxylnimbolinin (1) and 1α-tigloyloxy-3α-acetoxyl-7α-hydroxyl-12ß-ethoxylnimbolinin (2), together with other four known limonoids (3-6), were isolated from the fruits of Melia toosendan. Their structures were elucidated by means of extensive spectroscopic analyses (NMR and ESI-MS) and comparisons with the data reported in the literature. The isolated compounds were evaluated for their antibacterial activities. Compound 4 exhibited significant antibacterial activity against an oral pathogen, Porphyromonas gingivalis ATCC 33277, with an MIC value of 15.2 µg·mL(-1). Compound 2 was also active against P. gingivalis ATCC 33277, with an MIC value of 31.25 µg·mL(-1). In conlcusion, our resutls indicate that these compounds may provide a basis for future development of novel antibiotics.


Asunto(s)
Antibacterianos/aislamiento & purificación , Medicamentos Herbarios Chinos/aislamiento & purificación , Limoninas/aislamiento & purificación , Melia/química , Antibacterianos/química , Antibacterianos/farmacología , Medicamentos Herbarios Chinos/química , Frutas/química , Limoninas/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Porphyromonas gingivalis/efectos de los fármacos , Porphyromonas gingivalis/crecimiento & desarrollo , Espectrometría de Masa por Ionización de Electrospray
13.
Cancer Sci ; 107(10): 1506-1519, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27501331

RESUMEN

Advanced lung cancer has poor prognosis owing to its low sensitivity to current chemotherapy agents. Therefore, discovery of new therapeutic agents is urgently needed. In this study, we investigated the antitumor effects of peperomin E, a secolignan isolated from Peperomia dindygulensis, a frequently used Chinese folk medicine for lung cancer treatment. The results indicate that peperomin E has antiproliferative effects, promoting apoptosis and cell cycle arrest in non-small-cell lung cancer (NSCLC) cell lines in a dose-dependent manner, while showing lower toxicity against normal human lung epidermal cells. Peperomin E inhibited tumor growth in A549 xenograft BALB/c nude mice without significant secondary adverse effects, indicating that it may be safely used to treat NSCLC. Furthermore, the mechanisms underlying the anticancer effects of peperomin E have been investigated. Using an in silico target fishing method, we observed that peperomin E directly interacts with the active domain of DNA methyltransferase 1 (DNMT1), potentially affecting its genome methylation activity. Subsequent experiments verified that peperomin E decreased DNMT1 activity and expression, thereby decreasing global methylation and reactivating the epigenetically silenced tumor suppressor genes including RASSF1A, APC, RUNX3, and p16INK4, which in turn activates their mediated pro-apoptotic and cell cycle regulatory signaling pathways in lung cancer cells. The observations herein report for the first time that peperomin E is a potential chemotherapeutic agent for NSCLC. The anticancer effects of peperomin E may be partly attributable to its ability to demethylate and reactivate methylation-silenced tumor suppressor genes through direct inhibition of the activity and expression of DNMT1.


Asunto(s)
Benzodioxoles/farmacología , ADN (Citosina-5-)-Metiltransferasas/antagonistas & inhibidores , Silenciador del Gen , Genes Supresores de Tumor , Neoplasias Pulmonares/genética , Activación Transcripcional/efectos de los fármacos , Animales , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Benzodioxoles/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , ADN (Citosina-5-)-Metiltransferasas/química , ADN (Citosina-5-)-Metiltransferasas/metabolismo , Metilación de ADN , Modelos Animales de Enfermedad , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Humanos , Neoplasias Pulmonares/metabolismo , Ratones , Modelos Moleculares , Conformación Molecular , Unión Proteica , Relación Estructura-Actividad
14.
Nat Prod Res ; 30(21): 2495-9, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27313126

RESUMEN

Phytochemical investigation of the ethanol extract from the whole plant of Agrimonia pilosa led to the isolation of 31 compounds, including 16 flavonoids (1-16), 5 triterpenes (17-21), 1 isocoumarin (22), 5 phenolic acids (23-27), 1 ceramide (28), 2 agrimols (29-30) and 1 fatty acid (31). Their structures were determined by various spectroscopic analyses. Compounds 5, 7 and 20 were firstly isolated from the genus Agrimonia, and compounds 6, 10-11, 15, 26, 28 and 31 were isolated from the family Rosaceae for the first time. Moreover, the chemotaxonomic significance of these compounds was summarised.


Asunto(s)
Agrimonia/química , Agrimonia/clasificación , Flavonoides/análisis , Flavonoides/química , Extractos Vegetales/análisis , Triterpenos/análisis , Triterpenos/química
15.
Phytomedicine ; 23(8): 818-27, 2016 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-27288917

RESUMEN

BACKGROUND: Peperomin E (PepE) is a type of secolignan that is a major component of the plant Peperomia dindygulensis. It has been shown to exert anticancer effects in various cancer cell lines; however, the effects of PepE on human gastric cancer remain unexplored. PURPOSE: The aim of this study was to investigate the effectiveness of PepE as a treatment of gastric cancer and to identify the underlying mechanisms of its anticancer activity. STUDY DESIGN: The efficacy of PepE was examined using human gastric carcinoma SGC-7901, BGC-823, MKN-45 cell lines and normal gastric epithelial GES-1 cell line as an in vitro model and SGC-7901 xenograft mice as an in vivo model. METHODS: Cell viability assays were used to examine the anticancer effect of 0-204.8µM concentrations of PepE in vitro. Additionally, flow cytometry and western blotting were used to elucidate the mechanism with a particular focus on apoptosis. SGC-7901 cells were injected into BALB/c mice, which were then treated with 5 or 15mg/kg/day dose of PepE. The in vivo activity of PepE was investigated by measuring tumors and conducting immunohistochemistry experiments. The safety of PepE was investigated by measuring blood biochemical parameters and conducting histopathological analysis. Taxol was used throughout as a positive control. RESULTS: The results showed that PepE exhibited antiproliferative effects against gastric cancer cells and induced their apoptosis in a dose dependent manner with lower toxicity against normal gastric epithelial cells. Mechanistic evaluations indicated that PepE induced apoptosis by reducing the mitochondrial membrane potential (MTP), inducing cytochrome C release from mitochondria, reducing the ratio of Bcl-2/Bax and Bcl-xl/Bad, increasing activation of caspase-3, and decreasing the levels of PI3K and pAkt. The apoptotic effect of PepE on SGC-7901 cells was partially blocked by an Akt activator SC79. PepE potently inhibited in vivo tumor growth with no obvious toxicity following subcutaneous inoculation of SGC-7901 cells in nude mice. CONCLUSIONS: These findings indicate that PepE can inhibit cell proliferation and induce apoptosis of gastric cancer cells through mitochondrial and PI3K/Akt signaling pathways with relative safety and may be a novel effective chemotherapeutic agent against gastric cancer.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Benzodioxoles/farmacología , Mitocondrias/efectos de los fármacos , Proteína Oncogénica v-akt/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Animales , Carcinoma/tratamiento farmacológico , Carcinoma/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Trasplante de Neoplasias , Paclitaxel/uso terapéutico , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/patología
17.
Nat Prod Res ; 29(9): 795-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25560313

RESUMEN

A new ellagic acid derivative, 3,3'-dimethylellagic acid-4'-O-(6″-galloyl)-ß-D-glucoside, named runcinatside (5), together with four known compounds 3,3'-dimethylellagic acid (1), 3,3',4'-trimethylellagic acid (2), 3,3'-dimethylellagic acid-4'-O-ß-D-glucoside (3) and 3-methylellagic acid-4'-O-α-L-rhamno-pyranoside (4), was isolated from the roots of Polygonum runcinatum Buch.-Ham. ex D.Don Var. sinense Hemsl and the structures of these compounds were established by spectroscopic methods and comparison with previously reported data. All compounds showed antioxidant activities in vitro and compound 5 possessed the highest activity.


Asunto(s)
Antioxidantes/química , Ácido Elágico/análogos & derivados , Raíces de Plantas/química , Polygonaceae/química , Ácido Elágico/química , Ácido Elágico/aislamiento & purificación , Glucósidos/química , Glucósidos/aislamiento & purificación , Concentración 50 Inhibidora , Estructura Molecular
18.
Nat Prod Res ; 28(20): 1772-6, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24995563

RESUMEN

A new flavone glycoside, wogonin 7-O-ß-D-ethylglucuronide (1), together with a new natural flavone glycoside baicalein 7-O-ß-D-ethylglucuronide (2) and four known analogues, wogonoside (3), wogonin (4), oroxylin A 7-O-ß-D-methylglucuronide (5) and oroxylin A (6), was isolated from the roots of Scutellaria baicalensis Georgi. The structure elucidation of the new compound was primarily based on HR-ESI-MS, 1D and 2D NMR analyses. Compounds 1 and 3 inhibited FeSO4-Cys-induced liver homogenate lipid peroxidation with IC50 at 18.2 µM and 24.9 µM, respectively, and exhibited strong cytoprotective effects against H2O2-induced oxidative damage in human umbilical vein endothelial cells at low concentrations of 10.0 µM and 3.0 µM.


Asunto(s)
Antioxidantes/química , Flavanonas/química , Flavonas/química , Glucurónidos/química , Glicósidos/química , Raíces de Plantas/química , Scutellaria baicalensis/química , Animales , Antioxidantes/aislamiento & purificación , Flavanonas/aislamiento & purificación , Flavonas/aislamiento & purificación , Glucurónidos/aislamiento & purificación , Glicósidos/aislamiento & purificación , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Peroxidación de Lípido , Hígado/efectos de los fármacos , Estructura Molecular , Estrés Oxidativo , Ratas
19.
Nat Prod Res ; 28(15): 1214-7, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24896299

RESUMEN

Eleven compounds, including four flavonoids [(2R,3R)-2,3-dihydro-3,5-dihydroxy-7,4'-dimethoxyflavone (1), 5-hydroxy-7,8,4'-trimethoxy-flavone (2), amentoflavone (10) and apigenin (11)], two penylpropanoids [sinapaldehyde (3) and 3-methoxy-4-hydroxy-cinnamic aldehyde (4)], three phenolic acids [4-hydroxyl-3,5-dimethoxy-benzaldehyde (5), 4-hydroxyacetophen-one (6) and p-hydroxybenzaldehyde (7)], one furan derivative [5-hydroxymethyl furfural (8)] and one steroid saponin [ß-sitosterol-3-O-ß-d-glucoside (9)], were isolated and identified from Aletris spicata. Among them, compounds 1-7, 9 and 10 were reported from the genus Aletris for the first time. Furthermore, seven of them (1-6, 10) were obtained from the family Liliaceae for the first time. Chemotaxonomy of the isolated compounds is discussed briefly.


Asunto(s)
Flavonoides/aislamiento & purificación , Liliaceae/química , Magnoliopsida/química , Plantas Medicinales/química , Apigenina/química , Apigenina/aislamiento & purificación , Benzaldehídos/química , Flavonas/química , Flavonas/aislamiento & purificación , Flavonoides/química , Furaldehído/análogos & derivados , Furaldehído/química , Glucósidos/química , Glucósidos/aislamiento & purificación , Filogenia , Sitoesteroles/química
20.
Fitoterapia ; 96: 76-80, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24752140

RESUMEN

Two new dimeric diarylheptanoids, named Alpinin C (1) and D (2), a new natural product of diarylheptanoid (3) along with three known diarylheptanoids (4-6) were isolated from the rhizomes of Alpinia officinarum Hance. Their structures were elucidated based on extensive spectroscopic analyses (1D and 2D NMR, HRTOFMS, IR). The isolated compounds were evaluated for their cytotoxicity against human tumor cell lines HepG2, MCF-7, T98G and B16-F10. Compound 1 showed selective cytotoxicity against cell lines of MCF-7 and T98G, while compound 6 showed significant cytotoxicity to the all tested tumor cell lines with IC50 in the range from 8.46 to 22.68 µmol/L.


Asunto(s)
Alpinia/química , Antineoplásicos Fitogénicos/farmacología , Diarilheptanoides/farmacología , Extractos Vegetales/farmacología , Animales , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Diarilheptanoides/química , Diarilheptanoides/aislamiento & purificación , Humanos , Concentración 50 Inhibidora , Espectroscopía de Resonancia Magnética , Ratones , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Rizoma/química
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