Simultaneous Optimization of Microwave-Assisted Extraction of Phenolic Compounds and Antioxidant Activity of Avocado (Persea americana Mill.) Seeds Using Response Surface Methodology

Table 2

Central composite design (CCD) with observed response of the dependent variables from MAE of avocado seeds.

Independent variables				Phenolic compounds		Antioxidant activity
Run order	X1 (%)	X2 (W)	X3 (min)	TPC (mg·GAE/g)	TFC (mg·QE/g)	DPPH (%inhibition)	ABTS (%inhibition)
1	40	80	1	52.99	0.98	22.93	17.59
2	80	80	1	47.25	0.66	24.86	11.21
3	40	400	1	74.64	8.89	44.31	39.6
4	80	400	1	64.76	5.90	39.88	35.63
5	40	80	5	65.94	5.59	38.23	37.62
6	80	80	5	66.34	9.14	32.52	35.47
7	40	400	5	76.29	19.70	79.76	60.66
8	80	400	5	77.83	16.65	73.95	56.18
9	40	240	3	77.06	10.92	49.64	46.40
10	80	240	3	78.71	9.70	47.56	40.66
11	60	80	3	68.73	6.43	32.5	50.77
12	60	400	3	89.39	15.70	62.11	80.32
13	60	240	1	72.79	10.14	39.8	44.81
14	60	240	5	79.16	21.45	68.66	73.18
15	60	240	3	83.52	15.48	54.35	68.92
16	60	240	3	80.45	15.23	52.59	67.44
17	60	240	3	84.66	16.10	57.68	70.33

X₁ = ethanol concentration; X₂ = microwave power; X₃ = extraction time; TPC = total phenolic content; TFC = total flavonoid content; DPPH = 2,2-diphenyl-1-picrylhydrazyl radical scavenging ability; ABTS = 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) scavenging ability.