Comparative Metabolomics Analysis between Red- and White-Flowered Common Buckwheat Cultivars

Common buckwheat (Fagopyrum esculentum), a specialty crop in southwest China, is not only used as a supplement to primary grain crops but also to produce beverages, such as tea and wine. To fully exploit the productsmade from common buckwheat flower, ultra-performance liquid chromatography–electrospray ionization–tandem mass spectrometry (UPLC–ESI–MS/MS) was conducted to analyze the metabolites in red- (‘Guihong2’) and white-flowered (‘Fengtian 1’) buckwheat cultivars. A total of 784 metabolites were identified of whichflavonoids were the largest group with 191 components, followed by organic acids and derivatives (126), andamino acids and derivatives (95). Besides, dozens of phenylpropanoids, nucleotides and derivates, lipids, alkaloids as well as several kinds of indole derivatives and sterides were detected. Among these rich varieties ofmetabolites, 24 metabolites were only detected in the red flower that mainly included 8 anthocyanins and 6flavones, while 22 metabolites were only detected in the white flower, which mainly contained 5 lipids, 5flavonoids, and 5 organic acids and derivatives. Our results enrich the metabolites’ information of buckwheatand may be helpful for the exploitation of products from common buckwheat flowers.