Table 2. Pearson’s Correlation Coefficients (r) for the Relationships between Antioxidant Assays and the Phenolic Content.
| variables | TPC | TFC | TCT | DPPH | FRAP | ABTS | RPA | ·OH-RSA | FICA |
|---|---|---|---|---|---|---|---|---|---|
| TFC | 0.03 | ||||||||
| TCT | 0.97a | 0.22 | |||||||
| DPPH | 0.42 | –0.86 | 0.26 | ||||||
| FRAP | 0.90 | –0.29 | 0.80 | 0.61 | |||||
| ABTS | –0.88 | –0.36 | –0.95a | –0.16 | –0.60 | ||||
| RPA | –0.08 | 0.07 | –0.14 | –0.32 | 0.15 | 0.39 | |||
| ·OH-RSA | 0.54 | –0.79 | 0.35 | 0.90 | 0.81 | –0.14 | 0.08 | ||
| FICA | –0.96a | 0.07 | –0.90 | –0.46 | –0.94a | 0.74 | –0.12 | –0.66 | |
| TAC | 0.44 | 0.27 | 0.41 | –0.23 | 0.53 | –0.18 | 0.83 | 0.19 | –0.58 |
a
Significant correlation at p ≤ 0.05. TPC: total phenolic content; TFC: total flavonoid content; TTC: total tannin content; DPPH: 2,2′-diphenyl-1-picrylhydrazyl; FRAP: ferric reducing antioxidant power, ABTS: 2,2′-azinobis-(3-ethylbenzo-thiazoline-6-sulfonic acid); RPA: reducing power assay; ·OH-RSA: hydroxyl radical-scavenging activity; FICA: ferrous ion-chelating activity; and TAC: total antioxidant content.