Table 3.
Composition in organic acids (g/100 g fw) of purslane stems and leaves in relation to harvesting stage (mean ± SD).
| Harvest Stage (DAS) * |
Plant Part | Oxalic Acid | Quinic Acid | Malic Acid | Citric Acid | Total Organic Acids |
|---|---|---|---|---|---|---|
| 29 | Stems | 7.70 ± 0.07a | 6.36 ± 0.04a | 6.39 ± 0.07b | 5.00 ± 0.03a | 25.5 ± 0.2a |
| Leaves | 6.2 ± 0.1b | 6.82 ± 0.01c | 3.00 ± 0.03a | 3.26 ± 0.01a | 19.2 ± 0.1b | |
| 43 | Stems | 4.77 ± 0.01c | 1.31 ± 0.01c | 6.56 ± 0.07a | 1.57 ± 0.04c ¥ | 14.22 ± 0.04c |
| Leaves | 5.7 ± 0.1c | 8.4 ± 0.2b | 1.90 ± 0.04b | 1.53 ± 0.02b ¥ | 17.6 ± 0.1c | |
| 52 | Stems | 7.16 ± 0.02b | 3.57 ± 0.04b | 5.38 ± 0.06c | 2.78 ± 0.01b | 18.89 ± 0.04b |
| Leaves | 8.6 ± 0.2a | 16.8 ± 0.5a | 1.67 ± 0.01c | 3.24 ± 0.03a | 30.3 ± 0.2a | |
| 80 | Seeds | 0.470 ± 0.005 | nd | tr | tr | 0.470 ± 0.005 |
| Student’s t | Plant part ** | <0.001 | <0.001 | <0.001 | <0.001 | <0.001 |
nd: not detected; tr: traces; * DAS: days after sowing; ¥: no significant difference was observed between plant parts. Different Latin letters (a–c) in the same column refer to significant differences between harvest stages for the same plant part (stems or leaves) at p = 0.05. ** Comparison of means of different plant parts (stems and leaves) from the same harvest was performed with Student’s t-test at p = 0.05.