Metabolite profiling of phenolics, anthocyanins and flavonols in cabbage (Brassica oleracea var. capitata)

Metabolite profiling of phenolic acids, anthocyanidins and flavonols in Brassica oleracea var. capitata cultivated in the spring and fall seasons were evaluated. Phenolic acids (caffeic, p-coumaric, ferulic and sinapic acid), anthocyanidins (cyanidin and peonidin), and flavonols (quercetin and kaempferol) were identified and quantified by LC-MS and HPLC analyses. The total phenolic acid contents (10,633 μg/g DW) were increased 6.3-fold in red cabbages; in contrast, phenolic acids were present in significantly higher levels in the outer parts of the green cabbages in the spring sowing than in those of the fall sowing. In the case of red cabbages, the phenolic acid levels in the outer parts were higher (3147.5 μg/g DW), but the seasonal factor was not significant. Statistical analysis exhibited a significantly negative correlation between anthocyanidins and quercetin but exhibited a positive correlation between flavonols and phenolic acids in both cultivars. The most dramatic differences in the effect of the tissue position were analyzed by two-way MANOVA. The levels of anthocyanidins were 25-28% higher in the spring than those in the fall cabbages, whereas the contents were similar in the various tissue positions.