Modulation of Glucosinolate Composition in Brassicaceae Seeds by Germination and Fungal Elicitation

Glucosinolates (GSLs) are of interest for potential antimicrobial activity of their degradation products and exclusive presence in Brassicaceae. Compositional changes of aliphatic, benzenic, and indolic GSLs of Sinapis alba, Brassica napus, and B. juncea seeds by germination and fungal elicitation were studied. Rhizopus oryzae (non-pathogenic), Fusarium graminearum (non-pathogenic), and F. oxysporum (pathogenic) were employed. Thirty-one GSLs were detected by RP-UHPLC-PDA-ESI-MSn. Aromatic-acylated derivatives of 3-butenyl GSL, p-hydroxybenzyl GSL, and indol-3-ylmethyl GSL were for the first time tentatively annotated and confirmed to be not artefacts. For S. alba, germination, Rhizopus-elicitation, and F. graminearum-elicitation increased total GSL content, mainly consisting of p-hydroxybenzyl GSL, by 2-3 fold. For B. napus and B. juncea, total GSL content was unaffected by germination or elicitation. In all treatments, aliphatic GSL content was decreased (≥ 50%) in B. napus, and remained unchanged in B....