Table 1.
Total extraction yield (TEY), total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity (ABTS and FRAP) of SFE spruce extracts with different ethanol concentrations: SFE_10 (10%; v/v); SFE_20 (20%; v/v); SFE_40 (40%; v/v).
| TEY | TPC | TFC | ABTS | FRAP | |
|---|---|---|---|---|---|
| mg/g dw | mg GAEs/g dw | mg QEs/g dw | mg TEs/g dw | µmol FeSO4·7H2O/g dw | |
| SFE_10 | 28.6 ± 0.36 a | 0.77 ± 0.02 a | 0.47 ± 0.02 a | 2.48 ± 0.13 a | 8.31 ± 0.24 a |
| SFE_20 | 30.7 ± 0.96 a | 1.24 ± 0.07 b | 1.05 ± 0.15 b | 3.08 ± 0.16 b | 10.01 ± 0.81 b |
| SFE_40 | 31.2 ± 0.21 a | 2.50 ± 0.03 c | 1.75 ± 0.10 c | 5.29 ± 0.04 c | 25.49 ± 0.66 c |
Values are means of three replications ± standard deviation. Values in the same column followed by different superscript letters differ significantly (p < 0.05). SFE: supercritical fluid extraction. GAEs: gallic acid equivalents; QEs: quercetin equivalent; TEs: Trolox equivalent; FeSO4·7H2O: ferrous sulfate heptahydrate; ABTS: 2,2′-azinobis (3-ethylbenzothiazoline-6-sulfonic acid). FRAP: ferric reducing antioxidant power.