Faba bean (Vicia faba L.) is a legume cultivated worldwide. Due to their high yields and superior protein content compared to most other pulses, faba beans have gained popularity as an alternative and sustainable source of food for the global market.
The value of Australia’s faba beans production is estimated to be around 600,000 tonnes annually, with a worth of around 240 million per year.
Despite their desirable nutritional characteristics, faba bean contains the antinutritive compounds Vicine and Convicine, which are oxidatively metabolised after digestion into divicine and isouramil. While typically safe for human consumption, divicine and isouramil may pose a risk for a fraction of the human population having a genetic mutation that prevents the inactivation of divicine and isouramil. For this reason, researchers at the University of Adelaide are breeding new faba bean lines with a lower content in Vicine and Convicine.
Mass Spectrometry Imaging (MSI) can visualise the spatial distribution of small molecules across a tissue section. While MSI is increasingly applied, occasionally in combination with spatial transcriptomics, in proteomics and lipidomics, its application for small metabolite detection in plant tissues remains limited.
With our research reported here we aimed to:
Faba beans were cryo-sectioned into 10 μm thick slices and thaw mounted on microscope slides. The slides were matrix coated α-Cyano-4-hydroxycinnamic acid and analysed by Matrix-Assisted Laser Desorption Ionization (MALDI) Imaging MS in MS and MS/MS mode; pure reference standards of Vicine and Convicine were used to confirm the analyte identity.