The quality and glucosinolate composition of cruciferous sprouts under elicitor treatments using MeJA and LED lights

Cruciferous sprouts (Brassicaceae) are rich in glucosinolates/isothiocyanates (GSL/ITC), as health-promoters and also characteristic components for their organoleptic quality. The GSL/ITC are involved in the prevention and modulation of different pathological conditions (e.g. cancer, respiratory problems, metabolic and neurological disorders).

For the production of edible sprouts, only recently, the use of LED lights is growing in popularity as solution for indoor production and as sustainable system for the future of food supply. With this in mind, the aim of this study was to obtain edible sprouts of cruciferous species elicited by the use of LED lighting and natural hormones (Methyl-Jasmonate) as strategy to obtain naturally-functional fresh foods.

Seeds of cruciferous varieties (broccoli, red radish, red cabbage, and white mustard) were sanitized and aerated for 24h and allowed to grow for 2 more days in the dark. The 3-day old sprouts were grown under 18/6 h photoperiod under environmental controlled conditions using LED lights and Methyl-Jasmonate sprayed elicitor (250 µM MeJA). The efficiency in germination and biomass production as well as the phytochemical composition (GSL profiling) by HPLC-DAD-ESI-MSn analyses were carried out.

The preliminary evaluation of the data showed differences in terms of fresh weight production at harvest, depending on the variety and the growth conditions. The identification of GSL in these sprouts revealed qualitative differences according to variety and suggested the possibility of using specific GSL as markers for varieties: glucoraphanin (GRA) in broccoli; glucoraphenin (GRE) and Dehydro-Erucin (DH-ERN) in red radish; hydroxybenzyl-GLS (GSB) in white mustard, and glucoerucin (GER) in red cabbage. The effects of the LED lighting and the use of elicitor (MeJA) is a promising tool for increasing GSLs/ITCs contents in cruciferous sprouts, rendering a healthier fresh foods or ingredients for developing new functional products.