Extraction Optimization and Antioxidant Properties of African Eggplant (Solanum macrocarpon) Leaf Polyphenols
Table 2
Experimental design matrix by Box–Behnken for three level-three factors response surface study and responses.
Run
(°C)
(h)
(w/v)
Exp. yield (%)
Pred. yield
Exp. TPC (mg AAE/g)
Pred. TPC
Exp. TAA (mg AAE/g)
Pred. TAA
17.07
475.00 ± 0.53
476.84
17.98 ± 1.04
18.99
27.48 ± 0.07
26.89
164.13 ± 0.39
165.09
14.53 ± 0.54
13.04
24.50 ± 0.21
25.78
420.00 ± 1.28
421.94
21.53 ± 0.35
21.08
26.64 ± 0.16
27.99
172.14 ± 0.23
173.12
14.75 ± 1.05
13.58
20.41 ± 0.21
21.07
185.08 ± 0.21
185.09
15.76 ± 0.95
15.78
25.63 ± 0.02
26.00
304.10 ± 0.44
305.21
10.33 ± 0.20
11.90
24.12 ± 0.18
25.98
268.32 ± 0.88
267.09
11.25 ± 0.67
11.79
22.45 ± 0.36
23.98
406.33 ± 0.31
405.09
22.98 ± 0.09
22.76
24.21 ± 0.05
23.89
464.36 ± 0.73
465.00
22.15 ± 0.14
23.97
19.11 ± 0.12
20.98
263.80 ± 0.18
264.01
12.89 ± 0.05
12.11
26.56 ± 0.55
25.66
167.97 ± 0.61
166.98
15.35 ± 0.05
14.67
28.56 ± 0.23
28.00
97.25 ± 0.33
96.98
15.53 ± 1.05
16.35
26.83 ± 0.27
27.08
218.39 ± 0.35
217.09
13.43 ± 0.24
12.47
20.41 ± 0.06
21.03
268.64 ± 0.33
267.94
15.76 ± 0.95
16.45
24.72 ± 0.01
25.01
439.12 ± 0.45
438.99
15.17 ± 0.40
14.89
Note. Yield of extract, total polyphenol content (TPC), and total antioxidant activity (TAA) are represented as means ± standard deviation of triplicate determinations.
