Table 3.
Half-lives (h) and rate constants (k) of delphinidin (Dp) and petunidin (Pt) derivatives in pH 1–9, n = 3. Different superscript letters indicate significant differences (p < 0.05) between derivatives of the same anthocyanidin in the same pH.
| Anthocyanin | pH 1 | pH 2 | pH 3 | pH 4 | pH 5 | pH 6 | pH 7 | pH 8 | pH 9 |
|---|---|---|---|---|---|---|---|---|---|
| t1/2 (h) | |||||||||
| Dp-3-rut-5-glu | 675.0 b (9.3) | 378.7 a (16.8) | 102.7 a (6.2) | 34.2 b (5.5) | * NM | * NM | 1.7 c (0.0) | 1.1 c (0.0) | 0.7 c (0.0) |
| Dp-3-cis-p-cou-rut-5-glu | 1077.2 a (21.6) | 424.0 a (128.9) | 52.9 b (0.6) | 16.0c (0.2) | 13.08 b (0.2) | 12.8 b (0.0) | 12.6 a (0.1) | 8.6 b (0.1) | 7.5 b (0.4) |
| Dp-3-trans-p-cou-rut-5-glu | 666.3 b (47.6) | 457.5 a (26.2) | 89.2 a (7.2) | 53.9 a (1.6) | 67.5 a (8.4) | 18.3 a (7.7) | 7.7 b (0.1) | 13.2 a (0.7) | 13.7 a (0.6) |
| Pt-3-rut-5-glu | 183.9 b (26.0) | 65.3 b (5.3) | 28.5 a (1.9) | 18.0(1.5) | 19.5(2.5) | 6.5 a (0.2) | 1.7 b (0.0) | 2.5 b (0.0) | 1.1 c (0.0) |
| Pt-3-cis-p-cou-rut-5-glu | 546.8 b (20.3) | 137.4 a (19.8) | 17.8 b (1.7) | * NM | * NM | 1.9 b (0.1) | 1.8b (0.0) | 3.3 b (0.1) | 4.0 b (0.7) |
| Pt-3-trans-p-cou-rut-5-glu | 2309.6 a (389.1) | 109.7 a (11.8) | 25.3 a (2.6) | * NM | * NM | 7.1 a (0.8) | 4.2 a (0.1) | 7.3 a (0.6) | 5.5 a (0.6) |
| k | |||||||||
| Dp-3-rut-5-glu | 0.0010 (0.0000) | 0.0018 (0.0001) | 0.0068 (0.0004) | 0.0206 (0.0032) | * NM | * NM | 0.4004 (0.0034) | 0.6110 (0.0078) | 1.0377 (0.0583) |
| Dp-3-cis-p-cou-rut-5-glu | 0.0006 (0.0000) | 0.0017 (0.0005) | 0.0131 (0.0001) | 0.0433 (0.0006) | 0.0532 (0.0001) | 0.0540 (0.0001) | 0.0552 (0.0005) | 0.0808 (0.0005) | 0.0929 (0.0049) |
| Dp-3-trans-p-cou-rut-5-glu | 0.0010 (0.0001) | 0.0015 (0.0001) | 0.0078 (0.0007) | 0.0129 (0.0004) | 0.0104 (0.0012) | 0.0379 (0.0015) | 0.0900 (0.0009) | 0.0527 (0.0028) | 0.0507 (0.0020) |
| Pt-3-rut-5-glu | 0.0038 (0.0001) | 0.0107 (0.0001) | 0.0244 (0.0016) | 0.0386 (0.0032) | 0.0359 (0.0049) | 0.1073 (0.0029) | 0.4019 (0.0064) | 0.2780 (0.0033) | 0.6163 (0.0071) |
| Pt-3-cis-p-cou-rut-5-glu | 0.0013 (0.0000) | 0.0051 (0.0007) | 0.0391 (0.0040) | * NM | * NM | 0.3745 (0.0124) | 0.3832 (0.0091) | 0.2127 (0.0054) | 0.1751 (0.0329) |
| Pt-3-trans-p-cou-rut-5-glu | 0.0003 (0.0001) | 0.0064 (0.0001) | 0.0277 (0.0030) | * NM | * NM | 0.0988 (0.0118) | 0.1664 (0.0029) | 0.0956 (0.0070) | 0.1273 (0.0122) |
* NM: not measurable due to lack of absorbance at initial timepoint.