Author
MOCNIAK, LEANNE - University Of Auburn | |
Elkin, Kyle | |
Bryant, Ray | |
Soder, Kathy |
Submitted to: Talanta
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 7/20/2022 Publication Date: 8/2/2022 Citation: Mocniak, L.E., Elkin, K.R., Bryant, R.B., Soder, K.J. 2022. Building comprehensive glucosinolate profiles for brassica varieties. Talanta. 251:123814. https://doi.org/10.1016/j.talanta.2022.123814. DOI: https://doi.org/10.1016/j.talanta.2022.123814 Interpretive Summary: Glucosinolates are important plant compounds that play a role in reducing methane production and disease in livestock. This study by ARS scientists at University Park, PA tested a new methodology to determine individual glucosinolates in brassica forages. This simpler and more rapid method will allow researchers to more accurately identify glucosinolates for each forage species that may include specific glucosinolates that were not identified using previous methods. Better identification can improve animal production and reduce environmental impact of grazing livestock systems. Technical Abstract: The potential of high-resolution Q Exactive liquid chromatography orbitrap mass spectroscopy for screening of the total and individual glucosinolate (GLS) content of Brassica spp. was assessed. Three brassica species [‘Appin’ forage turnip (B. rapa L.), ‘Inspiration’ canola (B. napus L.), and ‘Barisca’ rapeseed (B. napus L.)] and a non-brassica control [‘KB Supreme’ annual ryegrass(Lolium multiflorum Lam.)] were analyzed for individual and total GLS content by extracting 0.5 g of freeze-dried herbage in 10 ml of 50°C 70% methanol for 15 minutes. An ICS-5000+ chromatography system interfaced to a Q Exactive orbitrap mass spectrometer and equipped with an ultra aqueous polar end-capped analytic column was used for GLS analysis. Turnip had the greatest (P = 0.0005) total GLS concentrations followed by rapeseed, and canola (27.9, 16.8, and 9.1 mg g-1 dry, respectively). Annual ryegrass contained no detectable concentration of any GLS. Screening of individual GLS revealed the presence of sinigrin, gluconapin, glucobrassicanapin, progoitrin, gluoerucin, gluconasturtiin, glucraphanin, and glucobrassicin. The use of this rapid and simple method would allow researchers to build a more robust GLS profile for each Brassica spp. that possibly includes GLS that were not identified using previous methods. |