Table 2. The retention time, calibration curves, and linearity (coefficient) of phenylpropanoids
| No | Compound | Retention time (min) | Calibration curve | Coefficient (R2) |
| 1 | Gallic acid | 7.41 | y = 32.5577x + 0.16012 | 1.0000 |
| 2 | Catechin | 15.37 | y = 7.8897x – 40.2424 | 1.0000 |
| 3 | 4-Hydroxybenzoic acid | 17.06 | y = 17.2445x + 23.1872 | 0.9998 |
| 4 | Chlorogenic acid | 17.34 | y = 18.0193x – 96.8840 | 0.9999 |
| 5 | Caffeic acid | 20.94 | y = 39.9829x – 65.7075 | 0.9999 |
| 6 | (-)-Epicatechin | 23.11 | y = 8.5989x – 8.3356 | 1.0000 |
| 7 | p-Coumaric acid | 31.83 | y = 63.4249x + 76.3047 | 0.9999 |
| 8 | Ferulic acid | 36.34 | y = 38.0673x + 11.5756 | 0.9997 |
| 9 | Sinapic acid | 37.16 | y = 16.6959x + 18.8045 | 0.9999 |
| 10 | Benzoic acid | 42.00 | y = 7.5252x – 37.3870 | 0.9997 |
| 11 | Rutin | 60.45 | y = 8.0971x – 105.5466 | 0.9995 |
| 12 | trans-Cinnamic acid | 65.37 | y = 91.6832x + 141.8036 | 0.9999 |
| 13 | Quercetin | 67.01 | y = 15.3926x – 284.3201 | 0.9996 |
| 14 | Kaempferol | 77.13 | y = 17.4491x – 68.6862 | 1.0000 |