Face-Centered Central Composite Design for the Optimization of the Extraction of Phenolic Compounds from Kernels and Shells of Raphia farinifera and Evaluation of the Antioxidant, Antimicrobial, and Anti-Inflammatory Activities
Table 1
Face-centered composite design with real and coded variables and experimental and predicted responses from the second-degree polynomial model.
Essay
Coded variables
Real variables
Experimental values
Predicted values
No.
Time (min)
Percentage ethanol (%)
Solvent/powder ratio (mL/g)
Time (min)
Percentage ethanol (%)
Solvent/powder ratio (mL/g)
TPC (mg GAE/L) shell extract
TPC (mg GAE/L) kernel extract
TPC (mg GAE/L) shell extract
TPC (mg GAE/L) kernel extract
1
-1
-1
-1
90
0
10
21.93
33.10
2
1
-1
-1
180
0
10
24.05
35.85
3
-1
1
-1
90
100
10
53.68
128.05
4
1
1
-1
180
100
10
63.54
129.38
5
-1
-1
1
90
0
30
47.51
49.65
6
1
-1
1
180
0
30
34.78
51.43
7
-1
1
1
90
100
30
58.27
116.34
8
1
1
1
180
100
30
53.28
116.71
9
-1
0
0
90
50
20
75.13
122.84
10
1
0
0
180
50
20
73.69
124.39
11
0
-1
0
135
0
20
58.83
56.338
12
0
1
0
135
100
20
83.95
136.44
13
0
0
-1
135
50
10
77.47
100.84
14
0
0
1
135
50
30
85.13
102.78
15
0
0
0
135
50
20
91.24
119.62
16
0
0
0
135
50
20
91.24
119.62
17
0
0
0
135
50
20
91.24
119.62
18
0
0
0
135
50
20
91.24
119.62
19
0
0
0
135
50
20
91.24
119.62
TPC: total phenolic compound; GAE: gallic acid equivalent.
