Table 2.

Experimental data for DPPH inhibition (%) from the Box–Behnken design

Experimental number	X1	X2	X3	DPPH inhibition (%)
				Actual value	Predicted value
1	1	−1	0	69.93 ± 3.38	66.79
2	0	0	0	70.07 ± 3.23	69.39
3	1	0	−1	61.12 ± 3.36	62.62
4	0	0	0	68.03 ± 2.53	69.39
5	−1	1	0	59.37 ± 3.90	62.51
6	0	−1	1	57.47 ± 2.75	59.27
7	1	0	1	60.09 ± 9.89	61.43
8	0	1	1	68.29 ± 2.93	66.65
9	−1	0	1	51.47 ± 5.06	49.97
10	0	0	0	70.07 ± 3.58	69.39
11	0	−1	−1	57.51 ± 2.51	59.15
12	0	1	−1	69.45 ± 3.33	67.65
13	1	1	0	70.70 ± 4.34	71.00
14	−1	0	−1	50.99 ± 3.87	49.65
15	−1	−1	0	51.14 ± 9.38	50.84