Table 2. Correlations between the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, phenolic compounds and malondialdehyde levels of vegetables.
| Vegetable | Test | Correlation coefficient (r) | ||
|---|---|---|---|---|
| DPPH radical scavenging activity (%) | Phenolic compounds (mg/dl) | Malondialdehyde (nmol/g) | ||
| Broccoli | DPPH radical scavenging activity (%) | 0.412* | 0.422* | |
| Phenolic compounds (mg/dl) | 0.412* | 0.309 | ||
| Malondialdehyde (nmol/g) | 0.422* | 0.309 | ||
| Cauliflower | DPPH radical scavenging activity (%) | -0.200 | -0.381* | |
| Phenolic compounds (mg/dl) | -0.200 | -0.022 | ||
| Malondialdehyde (nmol/g) | -0.381* | -0.022 | ||
| Garlic | DPPH radical scavenging activity (%) | 0.639** | 0.115 | |
| Phenolic compounds (mg/dl) | 0.639** | 0.112 | ||
| Malondialdehyde (nmol/g) | 0.115 | 0.112 | ||
| Onion | DPPH radical scavenging activity (%) | 0.467** | -0.644** | |
| Phenolic compounds (mg/dl) | 0.467** | -0.254 | ||
| Malondialdehyde (nmol/g) | -0.644** | -0.254 | ||
*P < 0.05; **P < 0.01.