Mass spectrometric characterisation of avenanthramides and enhancing their production by germination of oat (Avena sativa)
Bruijn, Wouter J.C. de; Dinteren, Sarah van; Gruppen, Harry ; Vincken, Jean Paul - \ 2019
Food Chemistry 277 (2019). - ISSN 0308-8146 - p. 682 - 690.
Avena sativa - Avenanthramides - Cereal grain - Germination - LC-MS - Phytoalexin - Plant defence - Poaceae
Avenanthramides are amides, with a phenylalkenoic acid (PA) and an anthranilic acid (AA) subunit, which are secondary metabolites of oat. Oat seeds were germinated, extracted, and the avenanthramides analysed by a combination of UHPLC with ion trap and high resolution ESI-MS. Typical fragmentation pathways with corresponding diagnostic fragments belonging to the PA and AA subunits were identified and summarised in a decision guideline. Based on these findings 28 unique avenanthramides were annotated in the oat seed(ling) extracts, including the new avenanthramide 6f (with a 4/5-methoxy AA subunit). Avenanthramide content increased by 25 times from seed to seedling. Avenanthramides 2p, 2c, and 2f, which are commonly described as the major avenanthramides, represented less than 20% of the total content in the seedlings. Future quantitative analyses should, therefore, include a wider range of avenanthramides to avoid underestimation of the total avenanthramide content.