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1.
Exp Eye Res ; 235: 109629, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37625574

RESUMEN

Chrysanthemum tea is commonly consumed by Chinese consumers mainly due to the Chrysanthemum flower being a potential source of antioxidants. The current study investigates the effects of extraction time and temperature on Chrysanthemum flower aqueous extract (CFAE) antioxidant capacity, including Trolox equivalent antioxidant capacity (TEAC), ferrous iron-chelating activity, and superoxide radical scavenging capacity (SRSC) using a two-factor, three-level factorial design of the response surface method (RSM). The TEAC and SRSC of CFAE are higher at higher temperatures and longer times up to a certain point, and the highest TEAC and SRSC are achieved at a 100 °C extraction temperature for 45 min. The fructose induced-αA-crystallin (Cry) glycation model system was used to evaluate the effects of the CFAE on anti-glycoxidation activities. The antioxidant ingredients obtained from CFAE significantly impede the production of advanced glycation end products from protein glycoxidation products (dityrosine, kynurenine, and N'-methylkynurenine) in the glycation process of αA-Cry and exhibit strong anti-glycating activity. The glycation inhibitory effects of CFAE are concentration-dependent. C. indicum L. exhibits greater potential for preventing cataracts compared to C. morifolium Ramat CFAE's antioxidant and anti-glycation properties suggest its potential application as a natural ingredient in the development of agents to combat glycation.


Asunto(s)
Chrysanthemum , Cristalinas , Humanos , Antioxidantes/farmacología , Extractos Vegetales/farmacología , Flores
2.
J R Soc Interface ; 19(192): 20220204, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35857904

RESUMEN

Silica bodies are commonly found in Selaginella, but their function is unclear. Lens-like appearance and location in many species above giant chloroplasts of dorsal epidermal cells suggest optical functions. Silica body morphology in three Selaginella species was studied by microscopy. Optical effects were assessed by wave-optic simulations. Large convex, approximately hemispherical (papillose) and small approximately conical (concave-convex) silica bodies were found in different species. Both types lead to a concentrated spot of light high in the dorsal epidermal cell. Large convex bodies concentrate light 10-25 times in a shape-dependent manner by refraction, and small silica bodies concentrate light in a shape-insensitive, but wavelength-dependent, manner by diffraction (red light: approx. 2.3 times; blue light: approx. 1.5 times). Due to chloroplast movement, this concentrated light is above the chloroplast under high light, but within it under low light. Beyond the spot of concentration, light is dispersed into the chloroplast. Thin Selaginella leaves mean these effects may enhance light capture and minimize photodamage, but other effects such as inhibition of herbivory, mechanical support, and immune responses need to be considered. Silica bodies undoubtedly have optical effects, but their significance to the functioning of the plant requires direct studies of ecophysiological performance.


Asunto(s)
Selaginellaceae , Cloroplastos/fisiología , Hojas de la Planta/fisiología , Dióxido de Silicio
3.
Sci Rep ; 10(1): 9462, 2020 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-32528013

RESUMEN

The asymmetric mandibles of termites are hypothetically more efficient, rapid, and powerful than the symmetric mandibles of snap-jaw ants or termites. We investigated the velocity, force, precision, and defensive performance of the asymmetric mandibular snaps of a termite species, Pericapritermes nitobei. Ultrahigh-speed recordings of termites revealed a new record in biological movement, with a peak linear velocity of 89.7-132.4 m/s within 8.68 µs after snapping, which caused an impact force of 105.8-156.2 mN. High-speed video recordings of ball-strike experiments on termites were analysed using the principle of energy conservation; the left mandibles precisely hit metal balls at the left-to-front side with a maximum linear velocity of 80.3 ± 15.9 m/s (44.0-107.7 m/s) and an impact force of 94.7 ± 18.8 mN (51.9-127.1 mN). In experimental fights between termites and ant predators, Pe. nitobei killed 90-100% of the generalist ants with a single snap and was less likely to harm specialist ponerine ants. Compared with other forms, the asymmetric snapping mandibles of Pe. nitobei required less elastic energy to achieve high velocity. Moreover, the ability of P. nitobei to strike its target at the front side is advantageous for defence in tunnels.


Asunto(s)
Hormigas/fisiología , Isópteros/fisiología , Mandíbula/fisiología , Animales , Fenómenos Biomecánicos/fisiología , Conducta Predatoria/fisiología
4.
J Biomed Sci ; 26(1): 12, 2019 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-30678675

RESUMEN

BACKGROUND: Osteoclasts (OCs) are motile multinucleated cells derived from differentiation and fusion of hematopoietic progenitors of the monocyte-macrophage lineage that undergo a multistep process called osteoclastogenesis. The biological function of OCs is to resorb bone matrix for controlling bone strength and integrity, which is essential for bone development. The bone resorption function is based on the remodelling of the actin cytoskeleton into an F-actin-rich structure known as the sealing zone for bone anchoring and matrix degradation. Non-muscle caldesmon (l-CaD) is known to participate in the regulation of actin cytoskeletal remodeling, but its function in osteoclastogenesis remains unclear. METHODS/RESULTS: In this study, gain and loss of the l-CaD level in RAW264.7 murine macrophages followed by RANKL induction was used as an experimental approach to examine the involvement of l-CaD in the control of cell fusion into multinucleated OCs in osteoclastogenesis. In comparison with controls, l-CaD overexpression significantly increased TRAP activity, actin ring structure and mineral substrate resorption in RANKL-induced cells. In contrast, gene silencing against l-CaD decreased the potential for RANKL-induced osteoclastogenesis and mineral substrate resorption. In addition, OC precursor cells with l-CaD overexpression and gene silencing followed by RANKL induction caused 13% increase and 24% decrease, respectively, in cell fusion index. To further understand the mechanistic action of l-CaD in the modulation of OC fusion, atomic force microscopy was used to resolve the mechanical changes of cell spreading and adhesion force in RANKL-induced cells with and without l-CaD overexpression or gene silencing. CONCLUSIONS: l-CaD plays a key role in the regulation of actin cytoskeletal remodeling for the formation of actin ring structure at the cell periphery, which may in turn alter the mechanical property of cell-spreading and cell surface adhesion force, thereby facilitating cell-cell fusion into multinucleated OCs during osteoclastogenesis.


Asunto(s)
Proteínas de Unión a Calmodulina/metabolismo , Diferenciación Celular , Osteoclastos/metabolismo , Osteogénesis , Animales , Macrófagos/metabolismo , Ratones , Células RAW 264.7
5.
J Plant Res ; 131(4): 655-670, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29500749

RESUMEN

Iridoplasts (modified plastids in adaxial epidermal cells) reported from Begonia were originally hypothesized to cause iridescence, which was broadly accepted for decades. However, several species of Begonia with iridoplasts are not iridescent causing confusion. Here chloroplast ultrastructure was observed in 40 taxa of Begoniaceae to explore the phenomenon of iridescence. However, 22 Begonias and Hillebrandia were found to have iridoplasts, but only nine display visually iridescent blue to blue-green leaves. Unexpectedly, a new type of plastid, a 'minichloroplast,' was found in the abaxial epidermal cells of all taxa, but was present in adaxial epidermal cells only if iridoplasts were absent. Comparative ultrastructural study of iridoplasts and a shading experiment of selected taxa show that a taxon with iridoplasts does not inevitably have visual iridescence, but iridescence is greatly affected by the spacing between thylakoid lamellae (stoma spacing). Thus, we propose instead the name 'lamelloplast' for plastids filled entirely with regular lamellae to avoid prejudging their function. To evaluate photosynthetic performance, chlorophyll fluorescence (F v /F m ) was measured separately from the chloroplasts in the adaxial epidermis and lower leaf tissues by using leaf dermal peels. Lamelloplasts and minichloroplasts have much lower photosynthetic efficiency than mesophyll chloroplasts. Nevertheless, photosynthetic proteins (psbA protein of PSII, RuBisCo and ATPase) were detected in both plastids as well as mesophyll chloroplasts in an immunogold labeling. Spectrometry revealed additional blue to blue-green peaks in visually iridescent leaves. Micro-spectrometry detected a blue peak from single blue spots in adaxial epidermal cells confirming that the color is derived from lamelloplasts. Presence of lamelloplasts or minichloroplasts is species specific and exclusive. High prevalence of lamelloplasts in Begoniaceae, including the basal clade Hillebrandia, highlights a unique evolutionary development. These new findings clarify the association between iridescence and lamelloplasts, and with implications for new directions in the study of plastid morphogenesis.


Asunto(s)
Begoniaceae/fisiología , Cloroplastos/fisiología , Fotosíntesis/fisiología , Plastidios/fisiología , Begoniaceae/ultraestructura , Cloroplastos/ultraestructura , Fluorescencia , Inmunohistoquímica , Iridiscencia , Microscopía Confocal , Microscopía Electrónica de Transmisión , Hojas de la Planta/fisiología , Hojas de la Planta/ultraestructura , Plastidios/ultraestructura
6.
Nat Prod Res ; 32(24): 2959-2963, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29067817

RESUMEN

The objective of this study was to evaluate the antioxidant activities of Mesona procumbens ethanolic extracts (MPEEs) which displayed variable antioxidant levels with different ethanolic concentrations. Compared to MPEEs with 20, 40 and 80% ethanol, the 60% MPEE exhibited a higher total phenol content (TPC), total flavonoid content (TFC), 1,1-diphenyl-2-picryl hydrazyl (DPPH)- and 2,2-azino-bis-(3-ethyl benzothiazoline-6-sulphonic acid (ABTS)-scavenging activities, reducing power, protection of Raw 264.7 mouse macrophages against H2O2-induced damage, and inhibition of reactive oxygen species (ROS) induced by 2,2-azobis(2-amidino propane) dihidrochloride (AAPH). IC50 values of DPPH and ABTS radicals by MPEEs were highly and significantly associated with TPCs and TFCs. The most significant protective effect against oxidative DNA damage was also found to be the 60% MPEE at a concentration of 3.6 mg/mL. In addition, the cell viability test showed that none of the MPEEs had any cell toxicity up to a concentration of 250 µg/mL. The 60% MPEE exhibited higher in vitro and ex vivo antioxidant activities, possessed a protective capability for the biological membrane system, and can be used as a functional ingredient representing a potential source of natural antioxidants to prevent and treat oxidative stress-related disorders.


Asunto(s)
Antioxidantes/aislamiento & purificación , Etanol/farmacología , Flavonoides/farmacología , Lamiaceae/efectos de los fármacos , Fenoles/análisis , Extractos Vegetales/farmacología , Antioxidantes/química , Supervivencia Celular/efectos de los fármacos , Daño del ADN/efectos de los fármacos , Flavonoides/química , Lamiaceae/metabolismo , Estrés Oxidativo/efectos de los fármacos , Fenoles/química , Extractos Vegetales/química , Sustancias Protectoras/química , Sustancias Protectoras/aislamiento & purificación , Sustancias Protectoras/farmacología
7.
Phys Med ; 39: 39-49, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28711187

RESUMEN

This study developed an in vitro diaphragm motion reproduction system (IVDMRS) based on noninvasive and real-time ultrasound imaging to track the internal displacement of the human diaphragm and diaphragm phantoms with a respiration simulation system (RSS). An ultrasound image tracking algorithm (UITA) was used to retrieve the displacement data of the tracking target and reproduce the diaphragm motion in real time using a red laser to irradiate the diaphragm phantom in vitro. This study also recorded the respiration patterns in 10 volunteers. Both simulated and the respiration patterns in 10 human volunteers signals were input to the RSS for conducting experiments involving the reproduction of diaphragm motion in vitro using the IVDMRS. The reproduction accuracy of the IVDMRS was calculated and analyzed. The results indicate that the respiration frequency substantially affects the correlation between ultrasound and kV images, as well as the reproduction accuracy of the IVDMRS due to the system delay time (0.35s) of ultrasound imaging and signal transmission. The utilization of a phase lead compensator (PLC) reduced the error caused by this delay, thereby improving the reproduction accuracy of the IVDMRS by 14.09-46.98%. Applying the IVDMRS in clinical treatments will allow medical staff to monitor the target displacements in real time by observing the movement of the laser beam. If the target displacement moves outside the planning target volume (PTV), the treatment can be immediately stopped to ensure that healthy tissues do not receive high doses of radiation.


Asunto(s)
Diafragma/fisiología , Fantasmas de Imagen , Respiración , Humanos , Movimiento , Ultrasonografía
8.
J Food Sci Technol ; 53(1): 902-8, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26788014

RESUMEN

The effects of water activity (aw) and temperature during storage on the physicochemical characteristics and functional properties of soy protein isolate (SPI) were investigated. SPI was stored with two different temperatures (25, 45 °C) and two levels of water activity (0.25, 0.75) for 224 days. During the 224-day storage period, all the samples showed decreases in gel hardness, emulsifying stability, foaming properties, viscosity, solubility, and color alteration, but increased in surface hydrophobicity (RSo). These alterations were stronger when stored at 45 °C than at 25 °C and in 0.75 aw than 0.25 aw, and most pronounced at 45 °C and 0.75 aw. Our results revealed that storage conditions - temperature and water activity - will indeed affect the functional properties of soy protein isolates.

9.
J R Soc Interface ; 11(97): 20140273, 2014 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-24920108

RESUMEN

Males of Dytiscinae beetles use specialized adhesive setae to adhere to female elytra during underwater courtship. This coevolution of male setae and female elytra has attracted much attention since Darwin. However, there has been little examination of their biomechanical functioning despite increasing knowledge on biofibrillar adhesion. Here, we report and compare, for the first time, the mechanisms of underwater attachment using two hair types, the primitive spatula and derived 'passive' sucker, found in male diving beetles. Results from interspecific scaling of protarsal palettes and adhesion by single seta suggest better performance in the later-evolved circular (sucker) setae. Spatula setae with a modified shallow sucker and channels use the combined mechanisms of suction and viscous resistance for adhesion. Velocity-dependent adhesion provides sufficient control for resisting the female's erratic movements while also detaching easily through slow peeling. Direction-dependent shear resistance helps reorient setae surfaces into a preferred direction for effective adhesion. Seta deformation using different mechanisms for circular and spatula setae reduces the force that is transmitted to the contact interface. A softer spring in spatula setae explains their adhesion at lower preloads and assists in complete substrate contact. Attachment mechanisms revealed in adhesive setae with modified spatula and passive suckers provide insights for bioinspired designs of underwater attachment devices.


Asunto(s)
Escarabajos/fisiología , Extremidades/fisiología , Cabello/fisiología , Inmersión/fisiopatología , Modelos Biológicos , Sensilos/fisiología , Adhesividad , Animales , Escarabajos/anatomía & histología , Simulación por Computador , Extremidades/anatomía & histología , Fricción , Masculino , Sensilos/anatomía & histología , Resistencia al Corte/fisiología , Estrés Mecánico , Viscosidad
10.
Food Chem ; 156: 369-73, 2014 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-24629982

RESUMEN

The aim of this study was to examine the fatty acid (FA) composition and levels in seeds of twelve native Camellia species collected in different populations of major producing regions in Taiwan. The constituents of FAs varied within and among populations. Oleic acid (OA) was found to be the predominant FA constituent in all species. Remarkably high levels of unsaturated OA and linoleic acid (LA), found in two populations of Camellia tenuiflora (CT), C. transarisanensis (CTA), and C. furfuracea (CFA), were similar to those reported for olive oil. The levels of saturated palmitic acid (PA) from most of the tested seed oils were less than 13%. Among the different fats, some FAs can be used as functional ingredients for topical applications. The seed oils of CT, CTA, and CFA possess chemical compounds that make them useful in health-oriented cooking due to their high OA and LA contents and low PA content.


Asunto(s)
Camellia/química , Aceites de Plantas/análisis , Semillas/química , Antioxidantes/química , Biodiversidad , Culinaria , Grasas/análisis , Ácidos Grasos/química , Geografía , Ácido Linoleico/análisis , Ácido Oléico/análisis , Ácido Palmítico/análisis , Taiwán
11.
BMC Genomics ; 14 Suppl 7: S1, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24564290

RESUMEN

BACKGROUND: Flow cytometry has been widely used for the diagnosis of various hematopoietic diseases. Although there have been advances in the number of biomarkers that can be analyzed simultaneously and technologies that enable fast performance, the diagnostic data are still interpreted by a manual gating strategy. The process is labor-intensive, time-consuming, and subject to human error. RESULTS: We used 80 sets of flow cytometry data from 44 healthy donors, 21 patients with chronic lymphocytic leukemia (CLL), and 15 patients with follicular lymphoma (FL). Approximately 15% of data from each group were used to build the profiles. Our approach was able to successfully identify 36/37 healthy donor cases, 18/18 CLL cases, and 12/13 FL cases. CONCLUSIONS: This proof-of-concept study demonstrated that an automated diagnosis of CLL and FL can be obtained by examining the cell capture rates of a test case using the computational method based on the multi-profile detection algorithm. The testing phase of our system is efficient and can facilitate diagnosis of B-lymphocyte neoplasms.


Asunto(s)
Linfocitos B/inmunología , Biomarcadores de Tumor/análisis , Citometría de Flujo/métodos , Leucemia Linfocítica Crónica de Células B/diagnóstico , Linfoma de Células B/diagnóstico , Algoritmos , Automatización de Laboratorios , Simulación por Computador , Humanos
12.
Int J Mol Sci ; 12(9): 6077-88, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22016645

RESUMEN

Moringa oleifera, Lam. (Moringaceae) is grown world-wide in the tropics and sub-tropics of Asia and Africa and contains abundant various nutrients. This study describes the effect of different parts (leaf, stem and stalk) and seasons (summer and winter) on the chemical compositions and antioxidant activity of M. oleifera grown in Taiwan. The results showed that the winter samples of Moringa had higher ash (except the stalk part), calcium and phenolic compounds (except the leaf part) and stronger antioxidative activity than summer samples. The methanolic extract of Moringa showed strong scavenging effect of DPPH radicals and reducing power. The trend of antioxidative activity as a function of the part of Moringa was: leaf > stem > stalk for samples from both seasons investigated. The Moringa extract showed strong hydrogen peroxide scavenging activity and high Superoxide Dismutase (SOD) activity except the stalk part.


Asunto(s)
Antioxidantes/metabolismo , Moringa oleifera/química , Hojas de la Planta/química , Tallos de la Planta/química , Estaciones del Año , Antioxidantes/farmacología , Ácido Ascórbico/metabolismo , Compuestos de Bifenilo/antagonistas & inhibidores , Compuestos de Bifenilo/metabolismo , Calcio/metabolismo , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/metabolismo , Depuradores de Radicales Libres/farmacología , Radicales Libres/antagonistas & inhibidores , Radicales Libres/metabolismo , Peróxido de Hidrógeno/antagonistas & inhibidores , Peróxido de Hidrógeno/metabolismo , Metanol/química , Fenol/metabolismo , Picratos/antagonistas & inhibidores , Picratos/metabolismo , Extractos Vegetales/química , Extractos Vegetales/metabolismo , Extractos Vegetales/farmacología , Superóxido Dismutasa/metabolismo , Taiwán
13.
J Food Sci ; 74(6): M294-301, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19723214

RESUMEN

Response surface methodology (RSM) was used to determine the optimum combinations of 3 factors, cooking time (40 to 120 min), inoculated bacteria populations (10(1) to 10(9) cells/100 g), and fermentation time (12 to 36 h) for producing black soybean natto. All of the responses (hardness, viscosity, and trichloacetic acid-soluble nitrogen) were significantly affected by the 3 factors. Fermentation time was the most important factor affecting quality of black soybean natto. Optimum combinations were cooking time 110 min, inoculated bacteria populations 10(2) to 10(4) cells/100 g, and fermentation time 30 to 33 h.


Asunto(s)
Bacillus/metabolismo , Manipulación de Alimentos/métodos , Glycine max , Alimentos de Soja , Bacillus/crecimiento & desarrollo , Intervalos de Confianza , Fermentación , Microbiología de Alimentos , Dureza , Calor , Modelos Estadísticos , Control de Calidad , Proyectos de Investigación , Factores de Tiempo , Viscosidad
14.
Biochim Biophys Acta ; 1788(6): 1287-95, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19366588

RESUMEN

Subcellular localization of a photosensitizer is critical to its therapeutic outcome during photodynamic therapy (PDT). We delineated the distribution of hypericin, a new generation photosensitizer, in model membrane systems to identify the operating principles of its subcellular accumulation. Results from fluorescence microscopy indicated preferential incorporation of hypericin in lipid of giant unilamellar vesicles. Monolayer fluorescence measurements further identified cholesterol as the key determinant for the observed selectivity of hypericin. The emission spectra of hypericin in lipid monolayers varied in a lipid-dependent manner and Stoke's shift behavior suggests that hypericin may form closely packed structure with cholesterol. Overall, our data lead to the conclusion that cholesterol is the major origin of the selectivity for hypericin in membrane systems. A hypothetical model depicting the intracellular and intravascular co-transport of hypericin and cholesterol because of their high affinity is presented.


Asunto(s)
Liposomas/química , Perileno/análogos & derivados , 1,2-Dipalmitoilfosfatidilcolina/química , Antracenos , Canales de Calcio/análisis , Colesterol/química , Suplementos Dietéticos , Dimiristoilfosfatidilcolina/química , Lípidos/química , Modelos Moleculares , Perileno/análisis , Perileno/química , Fosfatidilcolinas/química , Espectrometría de Fluorescencia , Propiedades de Superficie
15.
J Nanosci Nanotechnol ; 7(4-5): 1406-13, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17450906

RESUMEN

Using neutron reflectivity with contrast variation, X-ray reflectivity, and grazing incident small-angle X-ray scattering (GISAXS), we have characterized the in-depth and in-plane structural characteristics of the Langmuir and Langmuir-Blodgett (LB) films formed by a novel lecithin C60-derivative, FPTL, of three phospholipids jointly bonded on one single olefinic moiety of a C60 cage. Based on the neutron reflectivity measured, we have proposed a monolayer structure, with the C60 cages of FPTL lifted into the air and hydrophilic phospholipid heads immersed in water, for the FPTL Langmuir layer formed on water. On the other hand, the LB film of FPTL prepared on mica exhibits clear Kiessig fringes in the X-ray reflectivity profile, indicating a 27 angstroms monolayer film with less molecular orientation. With GISAXS, we have extracted an in-plane correlation length of about 210 A for a possible in-plane aggregation of C60 of FPTL in the LB monolayer. We have also demonstrated the highly ordered monolayer structures of a lecithin lipid, in elucidating the positive effect of the attached functional group-phospholipids on the monolayer formation of the lecithin C60-derivative.


Asunto(s)
Fulerenos/química , Nanotecnología/métodos , Fosfatidilcolinas/química , Modelos Químicos , Conformación Molecular , Estructura Molecular , Neutrones , Fosfolípidos/química , Presión , Dispersión de Radiación , Agua/química , Rayos X
16.
J Agric Food Chem ; 50(21): 5850-5, 2002 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-12358449

RESUMEN

An activity-directed fractionation and purification process was used to identify the antioxidative components of adlay hulls. Hulls of adlay (Coix lachryma-jobi L. var. ma-yuen Stapf) were extracted with methanol and then separated into water, 1-butanol, ethyl acetate, and hexane fractions. The 1-butanol-soluble fraction exhibited greater capacity to scavenge 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radicals when compared with fractions soluble in water, ethyl acetate, and hexane phases. The 1-butanol fraction was then subjected to separation and purification using Diaion HP-20 chromatography, silica gel chromatography, and HPLC. Six compounds showing strong antioxidant activity were identified by spectroscopic methods ((1)H NMR, (13)C NMR, IR, and MS) and by comparison with authentic samples to be coniferyl alcohol (1), syringic acid (2), ferulic acid (3), syringaresinol (4), 4-ketopinoresinol (5), and a new lignan, mayuenolide (6).


Asunto(s)
Depuradores de Radicales Libres/farmacología , Picratos , Poaceae/química , Antioxidantes/análisis , Antioxidantes/farmacología , Compuestos de Bifenilo , Cromatografía Líquida de Alta Presión , Espectroscopía de Resonancia Magnética , Metanol , Extractos Vegetales/química , Estructuras de las Plantas/química , Semillas/química
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