Optimized Conditions for Flavonoid Extraction from Pomelo Peel Byproducts under Enzyme- and Ultrasound-Assisted Extraction Using Response Surface Methodology

Table 1

Experimental values of the independent variables used in the Box–Behnken design (BBD).

Factor	−1	0	+1
Liquid-to-solid ratio, X1 (mL/g)	50	150	250
Enzyme concentration, X2 (v/m)	0.5	2.5	4.5
Incubation time, X3 (min)	40	60	80
Ultrasonic time, X4 (min)	30	60	90