Table 2.
Full 33 factorial design with the independent variables (X1, X2, and X3) and the responses on TPC1, DPPH2, FRAP3 and TFC4 for the hemp phenolic extracts
| Experiments | Levels | Responses | |||||
|---|---|---|---|---|---|---|---|
| X1 temperature (°C) | X2 time (min) | X3 extracting solvent | TPC (µmol GAE/g DM)5 | DPPH radical scavenging effect (%) | FRAP (mmol TE/g DM)6 | TFC (µmol QE/100 g DM)7 | |
| Control Me8 | 25 | 0 | Me70 | 13.51 ± 0.20 | 11.15 ± 0.28 | 0.27 ± 0.00 | 0.17 ± 0.02 |
| Control MA9 | 25 | 0 | Me + Ac | 20.48 ± 0.25 | 16.05 ± 0.39 | 0.41 ± 0.01 | 0.15 ± 0.00 |
| Control Ac10 | 25 | 0 | Ac80 | 24.84 ± 0.71 | 19.78 ± 0.56 | 0.61 ± 0.01 | 0.39 ± 0.02 |
| 1 | − 1 (140) | − 1 (5) | − 1 (Me70) | 14.04 ± 0.26 | 11.68 ± 0.91 | 0.28 ± 0.01 | 0.15 ± 0.00 |
| 2 | − 1 (140) | 0 (15) | − 1 (Me70) | 14.14 ± 0.22 | 12.42 ± 1.11 | 0.30 ± 0.00 | 0.15 ± 0.00 |
| 3 | − 1 (140) | 1 (30) | − 1 (Me70) | 15.49 ± 0.52 | 11.25 ± 1.23 | 0.33 ± 0.01 | 0.14 ± 0.00 |
| 4 | − 1 (140) | − 1 (5) | 0 (Me + Ac) | 21.16 ± 0.38 | 17.16 ± 0.68 | 0.42 ± 0.02 | 0.16 ± 0.00 |
| 5 | − 1 (140) | 0 (15) | 0 (Me + Ac) | 22.60 ± 0.56 | 19.62 ± 2.11 | 0.54 ± 0.01 | 0.17 ± 0.01 |
| 6 | − 1 (140) | 1 (30) | 0 (Me + Ac) | 24.09 ± 0.48 | 18.43 ± 1.83 | 0.48 ± 0.02 | 0.14 ± 0.01 |
| 7 | − 1 (140) | − 1 (5) | 1 (Ac80) | 25.63 ± 0.73 | 21.16 ± 2.12 | 0.67 ± 0.02 | 0.39 ± 0.02 |
| 8 | − 1 (140) | 0 (15) | 1 (Ac80) | 24.80 ± 0.60 | 20.80 ± 1.13 | 0.65 ± 0.02 | 0.35 ± 0.01 |
| 9 | − 1 (140) | 1 (30) | 1 (Ac80) | 27.52 ± 1.92 | 24.89 ± 0.76 | 0.72 ± 0.02 | 0.32 ± 001 |
| 10 | 0 (160) | − 1 (5) | − 1 (Me70) | 14.02 ± 0.36 | 10.62 ± 0.70 | 0.31 ± 0.01 | 0.24 ± 0.01 |
| 11 | 0 (160) | 0 (15) | − 1 (Me70) | 14.93 ± 1.33 | 9.92 ± 1.28 | 0.34 ± 0.01 | 0.20 ± 0.01 |
| 12 | 0 (160) | 1 (30) | − 1 (Me70) | 16.35 ± 0.72 | 11.05 ± 0.33 | 0.35 ± 0.02 | 0.18 ± 0.01 |
| 13 | 0 (160) | − 1 (5) | 0 (Me + Ac) | 21.62 ± 0.25 | 20.55 ± 2.11 | 0.46 ± 0.01 | 0.16 ± 0.01 |
| 14 | 0 (160) | 0 (15) | 0 (Me + Ac) | 24.14 ± 0.42 | 20.40 ± 0.35 | 0.54 ± 0.01 | 0.17 ± 0.01 |
| 15 | 0 (160) | 1 (30) | 0 (Me + Ac) | 24.94 ± 0.35 | 21.36 ± 0.48 | 0.47 ± 0.02 | 0.17 ± 0.01 |
| 16 | 0 (160) | − 1 (5) | 1 (Ac80) | 26.93 ± 0.76 | 23.76 ± 1.23 | 0.73 ± 0.02 | 0.38 ± 0.01 |
| 17 | 0 (160) | 0 (15) | 1 (Ac80) | 26.31 ± 1.24 | 22.94 ± 0.64 | 0.70 ± 0.06 | 0.35 ± 0.02 |
| 18 | 0 (160) | 1 (30) | 1 (Ac80) | 26.91 ± 1.84 | 23.77 ± 1.43 | 0.79 ± 0.05 | 0.33 ± 0.01 |
| 19 | 1 (180) | − 1 (5) | − 1 (Me70) | 15.14 ± 0.65 | 13.58 ± 1.06 | 0.30 ± 0.00 | 0.23 ± 0.01 |
| 20 | 1 (180) | 0 (15) | − 1 (Me70) | 16.15 ± 0.11 | 16.20 ± 1.30 | 0.36 ± 0.00 | 0.19 ± 0.01 |
| 21 | 1 (180) | 1 (30) | − 1 (Me70) | 16.73 ± 0.51 | 13.57 ± 0.36 | 0.40 ± 0.01 | 0.23 ± 0.01 |
| 22 | 1 (180) | − 1 (5) | 0 (Me + Ac) | 24.33 ± 0.20 | 21.24 ± 2.37 | 0.47 ± 0.01 | 0.17 ± 0.01 |
| 23 | 1 (180) | 0 (15) | 0 (Me + Ac) | 25.45 ± 0.46 | 17.95 ± 0.19 | 0.52 ± 0.02 | 0.17 ± 0.01 |
| 24 | 1 (180) | 1 (30) | 0 (Me + Ac) | 25.51 ± 2.27 | 19.63 ± 1.53 | 0.52 ± 0.07 | 0.21 ± 0.01 |
| 25 | 1 (180) | − 1 (5) | 1 (Ac80) | 27.63 ± 1.28 | 21.52 ± 0.16 | 0.77 ± 0.05 | 0.38 ± 0.01 |
| 26 | 1 (180) | 0 (15) | 1 (Ac80) | 28.43 ± 1.07 | 21.50 ± 1.87 | 0.93 ± 0.13 | 0.35 ± 0.01 |
| 27 | 1 (180) | 1 (30) | 1 (Ac80) | 30.58 ± 0.89 | 20.21 ± 1.86 | 0.88 ± 0.04 | 0.37 ± 0.01 |
Values are mean ± standard deviations done in triplicates (n = 3)
1TPC: total phenolic content; 2DPPH: 2,2-diphenyl-1-picrylhydrazyl; 3FRAP: Ferric reducing ability of plasma; 4TFC: total flavonoid content; 5 mg GAE/g DM: milligrams of gallic acid equivalents per gram of dry matter; 6mmols TE/g DM: millimoles of Trolox equivalents per gram of dry matter; 7 mg QE/100 g DM: milligrams of quercetin equivalents per 100 g of dry matter; 8Me70: Aqueous Methanol (70%, v/v); 9Me + Ac: mixture of aqueous acetone (80%, v/v) and aqueous methanol (70%, v/v) in a ratio of 1:1 (v/v); 10Ac80: Aqueous Acetone (80%, v/v)