Table 1.

Box–Behnken design with actual/coded values for the three variables, experimentally obtained and model predicted responses

Run	Variable levels			Experimental ABTS (%)	Predicted ABTS (%)	Experimental DPPH (%)	Predicted DPPH (%)	Experimental FRAP (µmol Fe2+ dm−3)	Predicted FRAP (µmol Fe2+ dm−3)
	X 1	X 2	X 3
1	100 (−1)	15 (−1)	2.05 (0)	85	84.94	42.67	41.54	19	13
2	500 (1)	15 (−1)	2.05 (0)	87.78	87.14	39.75	39.76	37	34
3	100 (−1)	30 (1)	2.05 (0)	85.71	86.87	43.11	45.46	17	20
4	500 (1)	30 (1)	2.05 (0)	89.52	89.07	44.9	43.68	2.819	8.45
5	100 (−1)	22.5 (0)	1.60 (−1)	85.4	84.36	42.44	44.23	27	30
6	500 (1)	22.5 (0)	1.60 (−1)	89.37	89.41	25.5	28.51	42	35
7	100 (−1)	22.5 (0)	2.50 (1)	82.06	82.01	43.8	40.79	23	22
8	500 (1)	22.5 (0)	2.50 (1)	80.32	81.36	54.76	52.97	21	26
9	300 (0)	15 (−1)	1.60 (−1)	82.54	83.38	47.82	45.02	27	36
10	300 (0)	30 (1)	1.60 (−1)	90.79	90.94	50.95	48.94	32	27
11	300 (0)	15 (−1)	2.50 (1)	83.97	83.82	51.62	55.53	28	27
12	300 (0)	30 (1)	2.50 (1)	80.95	80.11	58.57	59.45	21	18
13	300 (0)	22.5 (0)	2.05 (0)	86.03	85.91	43.11	43.1	56	55
14	300 (0)	22.5 (0)	2.05 (0)	87.00	85.91	45	43.1	60	55
15	300 (0)	22.5 (0)	2.05 (0)	85.01	85.91	43.2	43.1	52	55
16	300 (0)	22.5 (0)	2.05 (0)	85.72	85.91	41	43.1	53	55
17	300 (0)	22.5 (0)	2.05 (0)	85.82	85.91	43.2	43.1	55	55