Abstract: The present study was carried out to investigate the effect of tartary buckwheat protein (TBP) on metabolic pathways in hyperlipidemic mice and to explore its lipid-lowering mechanism from a metabonomic perspective. A hyperlipidemic mouse model was established by feeding mice a high-fat diet. Plasma metabolic fingerprinting was performed for normal, hyperlipidemic and TBP-treated mice using ultra-high performance liquid chromatography coupled with electrospray ionization tandem ion trap time-of-flight mass spectrometry (UPLC/ESI-IT-TOF/MS). The potential biomarkers for the intervention effect of TBP on hyperlipidemic mice and the related metabolic pathways were determined by partial least squares-discriminant analysis (PLS-DA) based on the metabolic network database. The results showed the presence of linoleic acid, cytidine diphosphate glycerol, phosphatidyl ethanolamine, galactosylceramide, cerebroside, glucosylceramide, phosphatidylcholine, glucuronide, prostaglandin G2, lysophosphatidic acid, lysophosphatidyl choline and sphingomyelin as 12 potential biomarkers in the plasma of hyperlipidemic mice. Tartary buckwheat protein could regulate 6 metabolic pathways (linoleic acid metabolism, glycerophospholipid metabolism, sphingolipid metabolism and pentose-glucuronic acid ester conversion, tryptophan metabolism and four arachidonic acid metabolism) in which 12 potential biomarkers are involved in hyperlipidemic mice, and restore them to normal, thereby ameliorating metabolic disorders in hyperlipidemic mice.

Key words: tartary buckwheat protein, hyperlipidemia, metabonomics, ultra performance liquid chromatography coupled with electrospray ionization tandem ion trap time-of-flight mass spectrometry