Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
1.
Antioxidants (Basel) ; 10(6)2021 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-34203940

RESUMEN

Lemon trees (Citrus limon (L.) Burm. F) were treated monthly with oxalic acid (OA) at 0.1, 0.5, and 1 mM from initial fruit growth on the tree until harvest in2019. The experiment was repeated in 2020, with the application of OA 1 mM (according to the best results of 2019). In both years, fruit from OA-treated trees and the controls were stored for 35 days at 10 °C. Results showed that all treatments reduced weight loss (WL) and maintained higher firmness, total soluble solids (TSS), and total acidity (TA) than in the controls. Meanwhile, colour (hue angle) did not show significant differences. The activity of antioxidant enzymes, catalase (CAT), ascorbate peroxidase (APX), and peroxidase (POD) in the flavedo of the fruit from the OA-treated trees was higher than in the controls at harvest and after 35 days of storage. Similarly, the total phenolic content (TPC) in the flavedo and juice of the fruit from the OA-treated trees were higher than in the controls. The increase in the activity of the antioxidant enzymes and TPC started with the first preharvest OA treatment and were maintained during fruit development on the tree until harvest. Preharvest OA treatments enhanced the antioxidant system of the lemon fruits, reducing the postharvest incidence of decay. Thus, OA could be a useful tool to increase the quality and functional properties of lemon fruits.

2.
Antioxidants (Basel) ; 10(6)2021 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-34063806

RESUMEN

The effect of melatonin pomegranate tree treatments on fruit quality and bioactive compounds with antioxidant activity at harvest and during storage at 10 °C for 60 days was assayed in two consecutive years, 2019 and 2020. In the first year, trees were treated with 0.1, 0.3 and 0.5 mM of melatonin along the developmental fruit growth cycle, and results showed that bioactive compounds (total phenolics and total and individual anthocyanins) and antioxidant activity at harvest were higher in fruits from melatonin-treated trees than in controls. Other fruit quality parameters, such as firmness, total soluble solids and aril red colour, were also increased as a consequence of melatonin treatment. In fruit from control tress, firmness and acidity levels decreased during storage, while increases occurred on total soluble solids, leading to fruit quality reductions. These changes were delayed, and even maintenance of total acidity was observed, in fruit from melatonin-treated trees with respect to controls, resulting in a fruit shelf-life increase. Moreover, concentration of phenolics and anthocyanins and antioxidant activity were maintained at higher levels in treated than in control fruits during the whole storage period. In general, all the mentioned effects were found at the highest level with the 0.1 mM melatonin dose, and then it was selected for repeating the experiment in the second year and results of the first year were confirmed. Thus, 0.1 mM melatonin treatment could be a useful tool to enhance aril content on bioactive compounds with antioxidant activity and health beneficial effects and to improve quality traits of pomegranate fruit, at harvest and during postharvest storage.

3.
Toxicon ; 127: 106-111, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28088478

RESUMEN

Adjuvant emulsions are widely used to enhance the antibody response of the animals used as immunoglobulin source for producing antivenoms. Usually, the adjuvant activity of emulsions is attributed both to their ability to trigger "danger" signals from cells in which they induce death, and to form depots from which immunogens are slowly released. However, there is contradictory evidence suggesting that adjuvant activity of emulsions is independent of the dispersion type and the rate of immunogen release. In order to test how physical properties of emulsions, composed of mineral oil and water, affect their ability to enhance the antibody response towards snake venoms, we compared water-in-oil (W/O) emulsions prepared at volume ratios of 70/30, 50/50 or 30/70, a 50/50 oil-in-water (O/W) emulsion, and a water-in-oil-in-water (W/O/W) multiple emulsion. Comparison included their droplet-size, viscosity, rate of immunogen release and ability to enhance the antibody response of mice immunized with the venom of the African viperid snake Echis ocellatus. It was found that all emulsions released a low amount of venom, and that the 50/50 (W/O) and the multiple emulsion (W/O/W) were those that induced the higher anti-venom antibody response. Our results suggest that the ability of emulsions to enhance the anti-venom response is not associated to their ability to form depots from which the venom is slowly released.


Asunto(s)
Adyuvantes Inmunológicos/química , Venenos de Víboras/inmunología , Viperidae , Adyuvantes Inmunológicos/farmacología , Animales , Formación de Anticuerpos , Emulsiones , Masculino , Ratones , Aceite Mineral/química , Agua/química
4.
Planta Med ; 81(8): 679-84, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26018918

RESUMEN

Accelerated solvent extraction (ASE®) was used to generate 18 macroalgal extracts from Irish seaweeds. The glycine betaine and dimethylsulfoniopriopionate content of the generated ASE® extracts were estimated using (1)H-NMR and confirmed for selected extracts using ultra performance liquid chromatography and mass spectrometry. Dimethylsulfoniopriopionate was only identified in the ASE® extract generated from Codium fragile ISCG0029. Glycine betaine was identified in the ASE® extract generated from Ulva intestinalis ISCG0356 using (1)H-NMR. Mass spectrometry analysis found that the seaweed species Cytoseira nodicaulis ISCG0070, Cytoseira tamariscofolia ISCG0283, and Polysiphonia lanosa ISCG0462 also had a glycine betaine content that ranged from 1.39 ng/ml to 105.11 ng/ml. Generated ASE® macroalgal extracts have potential for use as functional food ingredients in food products.


Asunto(s)
Betaína/aislamiento & purificación , Cardiotónicos/aislamiento & purificación , Alimentos Funcionales , Algas Marinas/química , Compuestos de Sulfonio/aislamiento & purificación , Betaína/química , Cardiotónicos/química , Cromatografía Liquida , Espectrometría de Masas , Solventes , Compuestos de Sulfonio/química
5.
Food Chem ; 160: 226-32, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-24799232

RESUMEN

The effects of salicylic acid (SA) or acetylsalicylic acid (ASA) treatments during on-tree cherry growth and ripening on fruit quality attributes, especially those related with the content on bioactive compounds and antioxidant activity were analysed in this research. For this purpose, two sweet cherry cultivars, 'Sweet Heart' and 'Sweet Late', were used and SA or ASA treatments, at 0.5, 1.0 and 2.0mM concentrations, were applied at three key points of fruit development (pit hardening, initial colour changes and onset of ripening). These treatments increased fruit weight and ameliorated quality attributes at commercial harvest, and led to cherries with higher concentration in total phenolics and in total anthocyanins, as well as higher antioxidant activity, in both hydrophilic and lipophilic fractions. Thus, preharvest treatments with SA or ASA could be promising tools to improve sweet cherry quality and health beneficial effects for consumers.


Asunto(s)
Antocianinas/análisis , Antioxidantes/análisis , Aspirina/química , Frutas/química , Extractos Vegetales/química , Prunus/química , Ácido Salicílico/análisis
6.
Phytochem Anal ; 25(2): 141-6, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24449540

RESUMEN

INTRODUCTION: Several analytical methods exist for the determination of sulphoraphane or sulphoraphane nitrile from biological matrices and plant extracts. However, no UPLC-MS/MS method exists for the simultaneous detection of both. OBJECTIVE: To develop and validate an UPLC-MS/MS method for the simultaneous analysis of sulphoraphane and sulphoraphane nitrile from Brassica oleracea L. ssp. italica METHODS: This method was developed utilising an Acquity BEH C8 column with gradient elution combined with tandem mass spectrometry, using positive electrospray ionisation in multiple reaction monitoring mode. RESULTS: The retention times for sulphoraphane and sulphoraphane nitrile were 0.4 and 0.6 min respectively, and total run time was 3 min. The method was validated for linearity, sensitivity, precision, accuracy, matrix effects and recovery. The method was employed to determine glucoraphanin hydrolysis products in broccoli and the predominant product was found to vary depending on the variety tested. It was also applied to the accurate determination of sulphoraphane and sulphoraphane nitrile in broccoli samples hydrolysed under different conditions. It was observed that the formation of sulphoraphane and sulphoraphane nitrile was influenced by the temperature of the reaction. CONCLUSION: The validated UPLC-MS/MS method for simultaneous detection of sulphoraphane and sulphoraphane nitrile was shown to be applicable to broccoli plants and is expected to be applicable to other cruciferous sources.


Asunto(s)
Brassica/química , Cromatografía Líquida de Alta Presión/métodos , Isotiocianatos/aislamiento & purificación , Nitrilos/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Sulfóxidos/aislamiento & purificación , Espectrometría de Masas en Tándem/métodos , Isotiocianatos/química , Nitrilos/química , Extractos Vegetales/química , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Sulfóxidos/química , Temperatura
7.
Nat Prod Commun ; 8(8): 1123-6, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24079184

RESUMEN

Falcarinol (9Z-heptadeca-1,9-diene-4,6-diyn-3-ol; (1) is a polyacetylene commonly found in several plant families. The absolute configuration of naturally occurring 1 is not clear and contradictory results have been reported in the literature. Determination of the absolute configuration of 1 from Pastinaca sativa L. was carried out. Isolation of 95% pure 1 was performed via successive fractionation and preparative-HPLC. A racemic mixture comprised of 3R-1 and 3S-1 was synthesized in order to confirm the absolute configuration of the isolated natural product using chiral HPLC. Based on a combination of chiral HPLC and specific rotation, 1 present in P. saliva was found to have a 3R absolute configuration (i.e. (3R, 9Z)-heptadeca-1,9-diene-4,6-diyn-3-ol).


Asunto(s)
Diinos/química , Diinos/aislamiento & purificación , Alcoholes Grasos/química , Alcoholes Grasos/aislamiento & purificación , Pastinaca/química , Cromatografía Líquida de Alta Presión , Conformación Molecular , Raíces de Plantas/química , Estereoisomerismo
8.
J Sci Food Agric ; 93(15): 3700-9, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23633428

RESUMEN

BACKGROUND: Responses of the soil microbial and nematode community to organic and conventional agricultural practices were studied using the Teagasc Kinsealy Systems Comparison trial as the experimental system. The trial is a long-term field experiment which divides conventional and organic agriculture into component pest-control and soil treatment practices. We hypothesised that management practices would affect soil ecology and used community level physiological profiles, microbial and nematode counts, and denaturing gradient gel electrophoresis (DGGE) to characterise soil microbial communities in plots used for onion (Allium cepa L.) cultivation. RESULTS: Microbial activity and culturable bacterial counts were significantly higher under fully organic management. Culturable fungi, actinomycete and nematode counts showed a consistent trend towards higher numbers under fully organic management but these data were not statistically significant. No differences were found in the fungal/bacterial ratio. DGGE banding patterns and sequencing of excised bands showed clear differences between treatments. Putative onion fungal pathogens were predominantly sequenced under conventional soil treatment practices whilst putative soil suppressive bacterial species were predominantly sequenced from the organic pest-control treatment plots. CONCLUSION: Organic management increased microbial activity and diversity. Sequence data was indicative of differences in functional groups and warrants further investigation.


Asunto(s)
Agricultura/métodos , Bacterias , Hongos , Nematodos , Cebollas , Microbiología del Suelo , Suelo , Animales , ADN Bacteriano , ADN de Hongos , Electroforesis en Gel de Gradiente Desnaturalizante , Ecosistema , Agricultura Orgánica/métodos
9.
Cir. Esp. (Ed. impr.) ; 74(6): 316-320, dic. 2003. ilus
Artículo en Es | IBECS | ID: ibc-26402

RESUMEN

En este trabajo hacemos una revisión de las infecciones necrosantes de la pared abdominal, ya que consideramos que pueden ser graves tras un traumatismo o una intervención quirúrgica sobre ellas. El diagnóstico clínico basado en los cultivos de gérmenes debe ser temprano, ya que, según los resultados, deberá instaurarse sin demora la antibioterapia adecuada y será preciso realizar desbridamientos amplios y agresivos. La mortalidad oscila entre el 30 y el 70 por ciento, y puede llegar al 80-100 por ciento en casos de retraso del diagnóstico o de aparición de shock séptico.Según el resultado de los cultivos efectuados, las variedades etiológicas son la mionecrosis por Clostridium y la fascitis necrosante (AU)


Asunto(s)
Humanos , Músculos Abdominales/microbiología , Fascitis Necrotizante/diagnóstico , Necrosis , Fascitis Necrotizante/tratamiento farmacológico , Fascitis Necrotizante/etiología , Diagnóstico Clínico , Infecciones por Clostridium/diagnóstico , Infecciones Estreptocócicas/diagnóstico , Gangrena/diagnóstico , Clostridium/aislamiento & purificación , Terapia por Inhalación de Oxígeno/métodos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA