Functional compounds in fermented buckwheat sprouts.

Fermented buckwheat sprouts (FBS) are used as multifunctional foods. Their production process includes fermentation with lactic acid bacteria. The major strains were found to include Lactobacillus plantarum, Lactobacillus brevis, Lactobacillus pentosus, Lactococcus lactis subsp. lactis, and Pediococcus pentosaceus in an investigation of the lactic acid bacteria. We searched for the functional components, and nicotianamine (NA) and 2″-hydroxynicotianamine (HNA) were identified as angiotensin I-converting enzyme (ACE) inhibitors. NA and HNA increased during fermentation. Indole-3-ethanol was identified as an antioxidant (a SOD active substance), and may have been generated from tryptophan during fermentation because it was not contained in green buckwheat juice. A safety test demonstrated that FBS contained were safe functional food components, showing negative results in buckwheat allergy tests. Any buckwheat allergy substances might have been degraded during the fermentation process.