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Nat Prod Res ; 31(10): 1181-1184, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27546074


Over the last decade, there has been an increasing interest to study the antioxidants from natural sources which can be applied to replace the synthetic compounds commonly used in food or as cosmetic ingredients. Calluna vulgaris (L.) Hull (heather), a plant grown in most parts of Europe and Northern America, has been used in ethnopharmacology. The content of selected biophenols and the antioxidant capacity of the extracts of wild heather collected from natural environmental localities of central Poland were assessed in this study and compared with cultivated plant. Chlorogenic acid was the major biophenolic compound present in the extracts, followed by a high amount of catechins. The reducing power of the extracts evaluated by Folin-Ciocalteau assay was in the range of 75.7-89.1 mg GA/g dry flowers. The cultivated plant extract showed the largest radical scavenging on 1,1-diphenyl-2-pirylhydrazyl (DPPH) radicals.

Antioxidantes/farmacología , Calluna/química , Ácido Clorogénico/análisis , Extractos Vegetales/farmacología , Calluna/crecimiento & desarrollo , Etnofarmacología , Flores/química
Ambio ; 44(2): 131-41, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24845194


Plant and soil bio(chemical) indicators are increasingly used to provide information on N deposition inputs and effects in a wide range of ecosystem types. However, many factors, including climate and site management history, have the potential to influence bioindicator relationships with N due to nutrient export and changing vegetation nutrient demands. We surveyed 33 heathlands in England, along a gradient of background N deposition (7.2-24.5 kg ha(-1) year(-1)), using Calluna vulgaris growth phase as a proxy for time since last management. Our survey confirmed soil nutrient accumulation with increasing time since management. Foliar N and phosphorus (P) concentrations in pioneer- and mature-phase vegetation significantly increased with N deposition. Significant interactions between climate and N deposition were also evident with, for example, higher foliar P concentrations in pioneer-phase vegetation at sites with higher temperatures and N deposition rates. Although oxidized N appeared more significant than reduced N, overall there were more, stronger relationships with total N deposition; suggesting efforts to control all emissions of N (i.e., both oxidized and reduced forms) will have ecological benefits.

Contaminantes Atmosféricos/metabolismo , Calluna/metabolismo , Monitoreo del Ambiente , Nitrógeno/metabolismo , Contaminantes del Suelo/metabolismo , Calluna/crecimiento & desarrollo , Ecosistema , Inglaterra , Fósforo/metabolismo , Hojas de la Planta/metabolismo
Plant Biol (Stuttg) ; 15(1): 226-32, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22672338


In Calluna vulgaris, a common bedding plant during autumn in the northern hemisphere, the bud-blooming mutation of flower morphology is of high economic importance. Breeding of new bud-blooming cultivars suffers from poor seed set in some of the desirable bud-flowering crossing partners. In the current study, fertilisation and seed development in genotypes with good or poor seed set were monitored in detail in order to examine pre- and post-zygotic cross breeding incompatibilities. Whereas no distinct differences were detected in seed development, pollen tube growth was impeded in the pistils of genotypes characterised by poor seed set. Detailed microscopic analysis revealed malformations of the gynoecia due to imperfect fusion of carpels. Hence, a pre-zygotic mechanism hindering pollen tube growth due to malformation of gynoecia was deduced. An interaction of putative candidate genes involved in malformation of gynoecia with floral organ identity genes controlling the flower architecture is discussed.

Calluna/crecimiento & desarrollo , Tubo Polínico/crecimiento & desarrollo , Semillas/crecimiento & desarrollo , Cruzamiento , Calluna/citología , Calluna/fisiología , Fertilización , Flores/citología , Flores/crecimiento & desarrollo , Flores/fisiología , Genotipo , Germinación , Polen/citología , Polen/crecimiento & desarrollo , Polen/fisiología , Tubo Polínico/citología , Tubo Polínico/fisiología , Polinización , Semillas/citología , Semillas/fisiología
Environ Pollut ; 156(2): 409-16, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18325647


The response of alpine heathland vegetation and soil chemistry to N additions of 0, 10, 20 and 50 kg N ha(-1) year(-1) in combination with simulated accidental fire (+/-) was monitored over a 5-year period. N addition caused rapid and significant increases in plant tissue N content and N:P and N:K of Calluna vulgaris, suggesting increasing phosphorus and potassium limitation of growth. Soil C:N declined significantly with N addition, indicating N saturation and increasing likelihood of N leakage. Fire further decreased soil C:N and reduced potential for sequestration of additional N. This study shows that alpine heathlands, which occupy the headwaters of many rivers, have limited potential to retain deposited N and may rapidly become N saturated, leaking N into downstream communities and surface waters.

Contaminantes Atmosféricos/farmacología , Calluna/crecimiento & desarrollo , Incendios , Nitrógeno/farmacología , Adsorción , Contaminantes Atmosféricos/toxicidad , Calluna/química , Calluna/metabolismo , Carbono/análisis , Carbono/metabolismo , Ecología/métodos , Ecosistema , Nitrógeno/toxicidad , Fósforo/análisis , Fósforo/metabolismo , Potasio/análisis , Potasio/metabolismo , Suelo/análisis , Contaminantes Químicos del Agua
Environ Pollut ; 155(2): 201-7, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18207619


Increased plant productivity due to nitrogen pollution increases the strength of the global carbon sink, but is implicated in plant diversity loss. However, modelling and experimental studies have suggested that these effects are constrained by availability of other nutrients. In a survey of element concentrations in Calluna vulgaris across an N deposition gradient in the UK, shoot concentrations of N and more surprisingly phosphorus and potassium were positively correlated with N deposition; tissue N/P ratio even decreased with N deposition. Elevated P and K concentrations possibly resulted from improved acquisition due to additional enzyme production or mycorrhizal activity. Heather occurs on organic soils where nutrient limitations are likely due to availability constraints rather than small stocks. However, if this effect extends to other plant and soil types, effects of N deposition on C sinks and plant competition may not be as constrained by availability of other nutrients as previously proposed.

Calluna/metabolismo , Nitrógeno/farmacología , Fósforo/análisis , Potasio/análisis , Contaminantes del Suelo/farmacología , Calluna/efectos de los fármacos , Calluna/crecimiento & desarrollo , Monitoreo del Ambiente/métodos , Fósforo/metabolismo , Brotes de la Planta/química , Brotes de la Planta/efectos de los fármacos , Brotes de la Planta/metabolismo , Potasio/metabolismo , Suelo/análisis , Reino Unido
Environ Pollut ; 148(1): 191-200, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17182158


On an upland moor dominated by pioneer Calluna vulgaris and with an understorey of mosses and lichens, experimental plots were treated with factorial combinations of nitrogen (N) at +0 and +20kg Nha(-1)yr(-1), and phosphorus (P) at +0 and +5kg Pha(-1)yr(-1). Over the 4-year duration of the experiment, the cover of the Calluna canopy increased in density over time as part of normal phenological development. Moss cover increased initially in response to N addition but then remained static; increases in cover in response to P addition became stronger over time, eventually causing reductions in the cover of the dominant Calluna canopy. Lichen cover virtually disappeared within 4 years in plots receiving +20kg Nha(-1)yr(-1) and also in separate plots receiving +10kg Nha(-1)yr(-1), but this effect was reversed by the addition of P.

Contaminantes Atmosféricos , Calluna/crecimiento & desarrollo , Ecosistema , Fertilizantes , Nitrógeno , Fósforo , Briófitas/crecimiento & desarrollo , Ecología/métodos , Monitoreo del Ambiente/métodos , Geografía , Líquenes/crecimiento & desarrollo , Tiempo , Reino Unido