Effects of Microwave-assisted L-phenylalanine Treatment on the Flavonoids of Tartary Buckwheat during Germination

In the study, tartary buckwheat sprouts of Chuanqiao 1 cultivar were investigated, and the effects of microwave-assisted L-phenylalanine (L-Phe) treatment on the flavonoids of tartary buckwheat during germination were studied. The content of flavonoids of tartary buckwheat sprouts was used as the standard, the single factor test and CCD response surface design methods were used to optimize the process of flavonoid enrichment by microwave-assisted L-Phe treatment of tartary buckwheat during germination. High performance liquid chromatography (HPLC) was used to analyze the flavonoid in tartary buckwheat sprouts. The results showed that the tartary buckwheat seeds were disinfected and germinated, then the seeds were treated by microwave with the power of 250 W for 90 s, the microwave temperature was (40±2)℃. Then, the tartary buckwheat seeds were cultured in the dark for 7 days at the condition of the temperature of 25 ℃ and the humidity of 75%±5% RH, and 2.90 mmol/L L-Phe solution was put into the germination tray as a nutrient solution. The result by detection showed the flavonoid content of tartary buckwheat sprouts on the 7th day was 6.26 g/100 g. Simultaneously, three flavonoids, chlorogenic acid, vitexin and rutin, were separated and determined by HPLC, and the content was 3.2764, 0.5644 and 31.8962 mg/g, respectively.