PDF(Pubmed)
Abstract：
For healthier human nutrition, it is desirable to provide food with a high content of nutraceuticals such as polyphenolics, vitamins, and carotenoids. We investigated to what extent high growth irradiance influences the content of phenolics, α-tocopherol and carotenoids, in wild rocket (Diplotaxis tenuifolia), which is increasingly used as a salad green. Potted plants were grown in a climate chamber with a 16 h day length at photosynthetic photon flux densities varying from 20 to 1250 μmol m-2 s-1. Measurements of the maximal quantum yield of photosystem II, FV/FM, and of the epoxidation state of the violaxanthin cycle (V-cycle) showed that the plants did not suffer from excessive light for photosynthesis. Contents of carotenoids belonging to the V-cycle, α-tocopherol and several quercetin derivatives, increased nearly linearly with irradiance. Nonintrusive measurements of chlorophyll fluorescence induced by UV-A and blue light relative to that induced by red light, indicating flavonoid and carotenoid content, allowed not only a semiquantitative measurement of both compounds but also allowed to follow their dynamic changes during reciprocal transfers between low and high growth irradiance. The results show that growth irradiance has a strong influence on the content of three different types of compounds with antioxidative properties and that it is possible to determine the contents of flavonoids and specific carotenoids in intact leaves using chlorophyll fluorescence. The results may be used for breeding to enhance healthy compounds in wild rocket leaves and to monitor their content for selection of appropriate genotypes.
摘要：
为了更健康的人类营养，希望提供具有高含量的营养食品，例如多酚，维生素,和类胡萝卜素。我们调查了高生长辐照度在多大程度上影响酚类物质的含量，α-生育酚和类胡萝卜素，在野生火箭（Diplotaxistenuifolia）中，越来越多地用作沙拉绿色。盆栽植物在气候室中生长，日长16小时，光合光子通量密度从20到1250μmolm-2s-1不等。光系统II的最大量子产率的测量，FV/FM,以及紫黄质循环（V循环）的环氧化状态表明，植物没有遭受过多的光合作用。属于V循环的类胡萝卜素的含量，α-生育酚和几种槲皮素衍生物，随着辐照度几乎线性增加。UV-A和蓝光相对于红光诱导的叶绿素荧光的非侵入性测量，表明类黄酮和类胡萝卜素的含量，不仅允许对两种化合物进行半定量测量，而且还允许在低生长辐照度和高生长辐照度之间的相互转移过程中跟踪其动态变化。结果表明，生长辐照度对三种不同类型的具有抗氧化性能的化合物的含量有很大影响，并且可以使用叶绿素荧光来确定完整叶片中的类黄酮和特定类胡萝卜素的含量。结果可用于育种，以增强野生火箭叶中的健康化合物，并监测其含量以选择合适的基因型。
