Experimental design for UAE and results obtained for TPC and antioxidant activity

Runs*FactorsResponses
X1X2X3X4Y1: TPC (mg GAE/100 g PDCF)Y2: FRAP (mg TE/100 g PDCF)Y3: ABTS (mg TE/100 g PDCF)
1870.10200.075458.9 ± 7.6 a770.1 ± 44.3 b10405.3 ± 666.3 c
2800.04300.100518.1 ± 11.6 b652.9 ± 5.2 a 4675.8 ± 76.3 b
3700.00200.075612.5 ± 8.7 b909.9 ± 41.2 c5613.0 ± 44.4 b
4700.1030.075672.5 ± 35.6 b962.5 ± 41.1 c4731.2 ± 666.9 b
5700.19200.075748.5 ± 4.7 c 1219.3 ± 55.9 e14258.3 ± 74.3 e
6700.10370.075622.9 ± 9.2 b1008.5± 17.4 d5672.2 ± 400.0 b
7800.04100.100408.0 ± 25.0 a723.7 ± 40.8 b4362.5 ± 195.5 b
8**700.10200.075564.8 ± 55.3 b1090.5 ± 29.0 d5463.1 ± 190.8 b
9700.10200.030871.2 ± 1.2 d1433.9 ± 1.1 g5020.3 ± 445.3 b
10800.15100.050554.4 ± 86.8 b916.4 ± 7.7 c3637.9 ± 394.0 a
11600.04300.051631.6 ± 79.4 b1163.6 ± 63.2 e12750.4 ± 449.8 d
12530.10200.075600.5 ± 65.4 b1311.9 ± 48.1 f13251.7 ± 665.0 d
13**700.10200.075639.7 ± 10.9 b1167.5 ± 40.9 e11058.5 ± 735.2 c
14600.15100.102570.8 ± 7.0 b1076.5 ± 47.8 e11519.1 ± 266.0 c
15600.15300.100591.1 ± 59.6 b1096.4 ± 9.94 e12632.8 ± 515.7 d
16600.04100.050717.2 ± 31.3 c 1177.4 ± 33.3 g13306.3 ± 46.4 d
17800.15300.050654.5 ± 70.2 b1052.8 ± 37.8 d9489.5 ± 62.2 b
18700.10200.120543.1 ± 16.6 b1037.6 ± 25.1 d12572.4 ± 220.4 d

Y1 (TPC-UAE) = –76.3287 – 17,494.9 × X4 + 48.5288 × X1 – 27.8374 × X3 + 3,660.92 × X2 + 25,101.3 × X42 + 119.06 × X4 × X1 + 52.4201 × X4 × X3 + 6,838.17 × X4 × X2 – 0.445927 × X12 + 0.346365 × X1 × X3 – 61.5881 × X1 × X2 – 0.037622 × X32 + 16.4098 × X3 × X2 + 2,971.08 × X22

Y2 (FRAP-UAE) = 26.6855 – 16,261.8 × X4 + 51.076 × X1 + 26.8571 × X3 + 719.841 × X2 + 22,844.6 × X42 + 155.681 × X4 × X1 – 86.7275 × X4 × X3 – 1,096.76 × X4 × X2 – 0.545876 × X12 + 0.0745313 × X1 × X3 – 4.13553 × X1 × X2 – 0.742027 × X32 + 5.47602 × X3 × X2 – 152.824 × X22

Y3 (ABTS-UAE) = 169,760 – 218,631 × X4 – 3,619.56 × X1 – 352.56 × X3 – 55,341.6 × X2+ 1.68226E6 × X4 2 – 1,270.48 × X4 × X1 – 1,934.39 × X4 × X3 + 193,392 × X4 × X2 + 21.2344 × X12 + 7.00881 × X1 × X3 + 544.449 × X1 × X2 – 2.1948 × X32 + 163.818 × X3 × X2 – 332.42 × X22

* Derived from a Draper-Lin reduced composite design (16 random orthogonal runs and ** 2 center points). X1: ethanol concentration (%); X2: emulsifier (%); X3: extraction time (min); X4: g PDCF/mL solvent; ABTS: radical scavenging activity. In each column samples with different letters are statistically different at the level of alpha = 0.05. Equations at the bottom of the table are those of the fitted model based on the regression coefficients for the different responses