Glucosinolate and carotenoid content of white- and yellow-flowering rapeseed grown for human consumption as sprouts and seedlings under light emitting diodes

Human consumption of rapeseed (Brassica napus L.) sprouts and seedlings is not common but with the development of new white-flowering cultivars, this has become a possibility. Therefore, we investigated the effect of two blue/red light ratios (low blue (LB) and high blue (HB)) provided by light emitting diodes (LED) on glucosinolate (GLS), total carotenoid, chlorophyll a and b contents in sprouts and seedlings of white- and yellow-flowering rapeseed. Highest fresh weight biomass (FW) was produced by a yellow-flowering cultivar as sprouts and seedlings and by a white-flowering cultivar as seedlings. Diverse effects of HB light were seen for FW in sprouts, whereas HB light reduced FW in seedlings. Progoitrin decreased under HB light treatment in the seedlings. Different cultivar responses were found for all individual GLSs, total aliphatic, indole and total GLSs. Total carotenoid content was affected by light treatment in sprouts, and cultivar differences were ascribed to higher carotenoid contents in yellow-flowering cultivars for both sprouts and seedlings. In conclusion, the effects of blue/red light ratios were of minor importance for GLS and carotenoid content, whereas cultivar selection had the highest impact altogether.