Table 2 Central composite design matrix for total polyphenol content (TPC), total flavonoid content (TFC), and DPPH radical scavenging activity of Hordeum vulgare L. under microwave-assisted extraction conditions

No	Ethanol concentration (%)	Microwave power (W)	Extraction time (min)	TPC (mg GAE/g)	TFC (mg RE/g)	DPPH (%)
1	25	120	8	3.17±0.081)	2.50±0.15	30.14±0.23
2	75	120	8	3.60±0.09	4.58±0.08	34.67±0.29
3	25	120	16	3.55±0.08	2.89±0.22	30.90±0.48
4	75	120	16	3.87±0.05	5.74±0.37	37.21±0.41
5	25	240	8	3.45±0.04	2.35±0.00	29.95±0.24
6	75	240	8	3.63±0.04	4.87±0.08	35.92±0.48
7	25	240	16	3.64±0.02	2.40±0.08	30.02±0.50
8	75	240	16	3.88±0.05	9.04±0.15	38.05±0.35
9	0	180	12	2.64±0.03	0.80±0.08	21.58±0.41
10	100	180	12	3.3±0.03	9.33±0.15	34.44±0.59
11	50	180	4	3.05±0.07	2.84±0.08	30.86±0.40
12	50	180	20	3.89±0.05	4.82±0.29	41.86±1.47
13	50	60	12	3.34±0.07	2.69±0.08	27.05±0.41
14	50	300	12	3.79±0.11	4.53±0.29	30.71±0.57
15	50	180	12	3.68±0.10	3.76±0.17	33.11±0.34
16	50	180	12	3.67±0.05	3.72±0.17	33.37±0.48

Mean±SD (n=3).