Optimization of Ultrasound-Assisted Extraction of Total Flavonoids from Dendranthema indicum var. aromaticum by Response Surface Methodology
Table 2
Five-level and three-variable central composite circumscribed (CCC) design for total flavonoids (TF) extraction in D. indicum var. aromaticum and observed responses.
Run
X1 (min)
X2 (g/mL)
X3 (°C)
TF extraction rate (g QEb/100 g DW)
1
20 (−1)
1 : 10 (−1)
40 (−1)
0.2586
2
40 (1)
1 : 10 (−1)
40 (−1)
0.3457
3
20 (−1)
1 : 30 (1)
40 (−1)
0.2385
4
40 (1)
1 : 30 (1)
40 (−1)
0.3104
5
20 (−1)
1 : 10 (−1)
60 (1)
0.4192
6
40 (1)
1 : 10 (−1)
60 (1)
0.4452
7
20 (−1)
1 : 30 (1)
60 (1)
0.3675
8
40 (1)
1 : 30 (1)
60 (1)
0.4109
9
13 (−1.68)
1 : 20 (0)
50 (0)
0.3177
10
47 (1.68)
1 : 20 (0)
50 (0)
0.4330
11
30 (0)
1 : 03 (−1.68)
50 (0)
0.2115
12
30 (0)
1 : 37 (1.68)
50 (0)
0.4189
13
30 (0)
1 : 20 (0)
33 (−1.68)
0.2644
14
30 (0)
1 : 20 (0)
67 (1.68)
0.4307
15
30 (0)
1 : 20 (0)
50 (0)
0.3811
16
30 (0)
1 : 20 (0)
50 (0)
0.3822
17
30 (0)
1 : 20 (0)
50 (0)
0.3840
18
30 (0)
1 : 20 (0)
50 (0)
0.4037
19
30 (0)
1 : 20 (0)
50 (0)
0.3788
20
30 (0)
1 : 20 (0)
50 (0)
0.3321
Note. Numbers in brackets are coded independent variables. bQuercetin equivalent.
