Consumption of flavonoid-rich foods and beverages is thought to reduce the risk of cardiovascular diseases. Whereas the biological activities of flavonoids have been characterized in vitro, there are no clear experimental data demonstrating that chronic dietary intake and intestinal absorption of flavonoids actually protects the heart against ischemia-reperfusion injury. We tested whether long-term consumption of specific flavonoids (anthocyanins) included in normal food could render the heart of rats more resistant to myocardial infarction. Maize kernels that differed specifically in their accumulation of anthocyanins were used to prepare rodent food in which anthocyanins were either present or absent. Male Wistar rats were fed the anthocyanin-rich (ACN-rich) or the anthocyanin-free (ACN-free) diet for a period of 8 wk. Anthocyanins were significantly absorbed and detected in the blood and urine of only rats fed the ACN-rich diet. In Langendorff preparations, the hearts of rats fed the ACN-rich diet were more resistant to regional ischemia and reperfusion insult. Moreover, on an in vivo model of coronary occlusion and reperfusion, infarct size was reduced in rats that ate the ACN-rich diet than in those that consumed the ACN-free diet (P < 0.01). Cardioprotection was associated with increased myocardial glutathione levels, suggesting that dietary anthocyanins might modulate cardiac antioxidant defenses. Our findings suggest important potential health benefits of foods rich in anthocyanins and emphasize the need to develop anthocyanin-rich functional foods with protective activities for promoting human health.

Significance: Selfing species wheat are bred as pure-line varieties with stagnating yield growths. In contrast, selection gain in maize is high, owing to massive investment sustained by hybrid seed sales, coupled with an efficient exploitation of hybrid vigor. We have developed a three-step strategy for establishing a heterotic pattern, which was one of the central unsolved challenges for initiating hybrid breeding programs. The benefits of our approach are demonstrated using data for wheat, but the strategy is relevant for several autogamous crops. Our three-step approach facilitates identification of a heterotic pattern, and thus may contribute to meeting the global challenge of increasing demand for food, feed, and fuel.

The effect of elevated CO₂ concentrations on the levels of secondary metabolites was investigated in tobacco plants grown under two nitrogen supply (5 and 8 mm NH₄NO₃) and CO₂ conditions (350 and 1000 p.p.m.) each. High CO₂ resulted in a dramatic increase of phenylpropanoids in the leaves, including the major carbon‐rich compound chlorogenic acid (CGA) and the coumarins scopolin and scopoletin at both nitrogen fertilizations. This was accompanied by increased PAL activity in leaves and roots, which was even higher at the lower nitrogen supply. Hardly any change was observed for the structural phenolic polymer lignin and the sesquiterpenoid capsidiol. In contrast, elevated CO₂ led to clearly decreased levels of the main nitrogen‐rich constituent nicotine at the lower N‐supply (5 mm NH₄NO₃) but not when plants were grown at the higher N‐supply (8 mm NH₄NO₃). Inoculation experiments with potato virus Y (PVY) were used to evaluate possible ecological consequences of elevated CO₂. The titre of viral coat‐protein was markedly reduced in leaves under these conditions at both nitrogen levels. Since PR‐gene expression and free salicylic acid (SA) levels remained unchanged at elevated CO₂, we suggest that the accumulation of phenylpropanoids, for example, the major compound CGA and the coumarins scopolin and scopoletin may result in an earlier confinement of the virus at high CO₂. Based on our results two final conclusions emerge. First, elevated CO₂ leads to a shift in secondary metabolite composition that is dependent on the availability of nitrogen. Second, changes in the pool of secondary metabolites have important consequences for plant–pathogen interactions as shown for PVY as a test organism.

A proteome study based on 2-D gel electrophoresis was performed in order to analyse the cold-stress response of Arabidopsis plants. The emphasis was to monitor the overall changes in the protein complement after prolonged exposure rather than short-term responses. Two different temperature regimes were used (6 °C and 10 °C) and plants were exposed to cold-stress exposure for 1 week. Protein patterns were also monitored after re-shifting plants to control conditions for a further week. To monitor gradual changes in the response to the two cold-stress conditions, the analysis was performed with DIGE technology with the inclusion of an internal standard. In the experiments using 6 °C, 22 spots with at least 2-fold altered expression were found; among them 18 were increased and four were decreased. When plants were exposed to 10 °C, 18 of these 22 spots still showed a 2-fold change; however, the alterations were, in general, more moderate than observed under 6 °C. Spot identification was performed by MALDI-TOF and ESI-MS/MS. Many of the proteins identified have previously been described in the context of cold-stress responses, indicating the validity of this proteome approach for further in-depth studies.