Ultrasound-assisted Extraction of Total Flavonoids from Wheat Sprout: Optimization Using Central Composite Design Method

The process of extracting active ingredients from wheat sprout using ultrasound assisted method was optimized with a central composite design model. The response value of the central composite design model established the extraction yield and the total flavonoids content, main effects and interactive effects were analyzed depending on independent variables such as the extraction time, volume ratio of ethanol to ultrapure water, and ultrasonic irradiation power. The volume ratio of ethanol to ultrapure water and ultrasonic irradiation power were relatively large for the extraction yield and the extraction time was most significantly affected the total flavonoids, Considering both the extraction yield and total flavonoids content, the optimal extraction conditions were as follows: the extraction time of 17.00 min, volume ratio of ethanol to ultrapure water of 50.25 vol%, ultrasonic irradiation power of 551.70 W. In this case, the extraction yield and total flavonoids content were 28.43 wt% and 29.99 mu g QE/mL dw, respectively. The actual experimental extraction yield and total flavonoids content under this condition were 8.73 wt% and 29.65 mu g QE/mL dw, respectively with respective error rates of 1.05 and 1.13%.