Identification, Characterization, and Quantification of an Anti-pyridoxine Factor from Flaxseed Using Ultrahigh-Performance Liquid Chromatography–Mass Spectrometry

In the present study, the anti-pyridoxine compounds linatine (1-[(n-γ-L-glutamyl)amino]-D-proline) and 1-amino-D-proline (1ADP) were quantified following extraction from defatted flaxseed using aqueous isopropanol as a solvent, with extraction variables including time, temperature, and the solid/solvent ratio. Both linatine and 1ADP were identified, characterized, and quantified via UPLC/ESI-MS using authentic standards. To optimize the extraction conditions for these anti-pyridoxine compounds, a response surface methodology was applied using a second-order polynomial to describe the experimental data. The predicted model for the optimal extraction was significant (P < 0.05) with a R(2) of 0.82. A varietal analysis showed that the amount of anti-pyridoxine present in flaxseed ranged from 177 to 437 μg 1ADPE/g of whole seed. The current study establishes the content of specific anti-pyridoxine factors in flaxseed and positions the data for use in subsequent risk assessment modeling.