Optimization of Flavonoid Extraction in Dendrobium officinale Leaves and Their Inhibitory Effects on Tyrosinase Activity

Table 1

PBD and results.

Run	Factor 1	Factor 2	Factor 3	Factor 4	Response
	Liquid Ratio; (mL/g; X1)	Time; (h; X2)	Number; (X3)	Ethanol; (%; X4)	Flavonoid; (mg/50mL)
1	1:60	2.5	3	80	24.58
2	1:40	2.5	5	70	24.96
3	1:60	1.5	5	80	32.28
4	1:40	2.5	3	80	26.18
5	1:40	1.5	5	70	24.45
6	1:40	1.5	3	80	22.04
7	1:60	1.5	3	70	22.58
8	1:60	2.5	3	70	20.98
9	1:60	2.5	5	70	27.31
10	1:40	2.5	5	80	30.68
11	1:60	1.5	5	80	32.28
12	1:40	1.5	3	70	21.98