Developmental aspects of flavonoid patterns in Brassica campestris var. oleifera: a preliminary study

Abstract

Field-grown plants of Brassica campestris L. var. oleifera (summer turnip rapeseed) were harvested at various growth stages from seedling through to maturity. Cotyledons, roots, hypocotyls, leaves, stems, and flowers were sampled as available and freeze-dried prior to extraction. Chlorophyll-free, unhydrolysed alcoholic extracts were subjected to two-dimensional chromatography on polyamide thin layers to establish flavonoid patterns. Major aglycones of compounds were tentatively identified on the basis of mobility, colour reactions with a diphenylboric acid ethanolamine spray, and co-chromatography with standards. Each organ was found to have a pattern characteristic to itself which changed little with age. The greatest variety of compounds was present in leaf tissues. Only two compounds, presumably highly glycosylated derivatives of quercetin, were common to all tissues.