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1.
Quantitative UPLC‐MS/MS analysis of chlorogenic acid derivatives in antioxidant fractionates from dandelion (Taraxacum officinale) root 下载免费PDF全文
Owen Kenny Thomas J. Smyth Chandralal M. Hewage Nigel P. Brunton 《International Journal of Food Science & Technology》2015,50(3):766-773
While qualitative studies have identified chlorogenic acids in antioxidant extracts, particularly ethyl acetate‐derived extracts, of Taraxacum officinale, quantitative analysis of these phenolic compounds remains largely unreported for this species. In this study, bioactivity‐guided fractionation of an antioxidant crude ethyl acetate extract (DPPH = 295.481 ± 0.955 mg TE g?1 extract) from T. officinale root resulted in a number of reverse‐phase fractions that demonstrated high antioxidant activity (DPPH = 1058.733–1312.136 mg TE g?1 extract), stronger than that of the synthetic antioxidant Trolox®. UPLC‐MS/MS screening of these fractions for the presence of selected mono‐ and di‐caffeoylquinic acids revealed large quantities of 1,5‐dicaffeoylquinic acid present in several fractions (853.052–907.324 μg mg?1), respectively. Due to the antioxidant potency and high levels of 1,5‐dicaffeoylquinic acid observed in these fractions, it was concluded that specifically this chlorogenic acid derivative is a major contributor to the antioxidant efficacy of dandelion root. 相似文献
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Rositi Hugo Appadoo Owen Kevin Mestre Daniel Valarier Sylvie Ombret Marie-Claire Gadea-Deschamps Émilie Barret-Grimault Christine Lohou Christophe 《Multimedia Tools and Applications》2021,80(2):1945-1967
Multimedia Tools and Applications - Microsoft has recently released a mixed reality headset called HoloLens. This semi-transparent visor headset allows the user who wears it to view the projection... 相似文献
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Stephen Owen 《Landscape Research》2005,30(1):57-79
The notion that English hill towns can be identified as a particular type of settlement is reinforced and a systematic analysis of the characteristics that contribute to their identity in the wider landscape is undertaken. Fourteen towns that meet the working definition of an English hill town are examined in terms of four sets of characteristics that constitute their distinctive features: the continuing imprint of their origins, location and early functions; the influence of natural physical features on their founding and subsequent development; their morphological form; and the visual characteristics that are the medium through which their identity is mainly experienced — pre-eminent amongst these are a town's visual profile, its figure - ground relationship with the landscape, and its skyline. Groups of hill towns with consistent characteristics are identified, including 'classic' English hill towns. While the analysis is not directed explicitly towards the development and implementation of planning policy, the fuller understanding of hill towns gained through the analysis should enrich the policy process. 相似文献
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Wade AJ Soulsby C Langan SJ Whitehead PG Edwards AC Butterfield D Smart RP Cook Y Owen RP 《The Science of the total environment》2001,265(1-3):229-252
The Integrated Nitrogen in CAtchments model (INCA) was applied to the River Dee, Aberdeenshire, NE Scotland. To a first approximation the model was able to simulate the annual mean streamwater NO3-N concentrations observed along the length of the main channel. This provided the basis for using INCA to subsequently explore the effects of N deposition and land use management on streamwater NO3-N concentrations and loads. On an annual timescale, the model predictions suggest that NO3-N concentrations will decrease by 5% following a 20% reduction in fertiliser application. Furthermore, model results also suggest that a 50% increase in N deposition will cause a 15% increase in the streamwater NO3-N concentrations. The utility of INCA as a tool for catchment management is discussed, current limitations are highlighted and possible improvements are suggested. 相似文献
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