Table 5.
Arabinan composition (mol%) of the non-starch polysaccharides of different apple cultivars before and after storage as determined by two-dimensional NMR spectroscopy after endo-arabinanase digestion.
| A | B | C | D | E | F | G | H | I | J | K | L | M | N | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 5-/1,5-Araf | 19.5 | 16.6 | 5.8 | 19.1 | 15.9 | 17.1 | 16.0 | 20.1 | 16.9 | 20.1 | 10.5 | 17.5 | 18.2 | 19.9 |
| t-O5-Araf | 15.1 | 13.5 | 14.0 | 14.7 | 15.7 | 14.8 | 14.0 | 13.6 | 13.6 | 9.8 | 15.6 | 13.6 | 15.3 | 14.8 |
| t-O2-Araf | 15.4 | 18.4 | 16.1 | 17.6 | 22.4 | 15.5 | 13.5 | 10.7 | 15.8 | 11.5 | 14.6 | 16.1 | 19.1 | 13.8 |
| t-O3-Araf | 21.5 | 24.3 | 26.4 | 24.0 | 21.4 | 25.2 | 28.0 | 25.9 | 24.9 | 27.8 | 26.7 | 25.2 | 19.8 | 23.0 |
| Σ 5-/1,5-/t-O5-Araf | 34.5 | 30.0 | 19.8 | 33.8 | 31.5 | 31.9 | 29.9 | 33.6 | 30.5 | 29.9 | 26.1 | 31.1 | 33.5 | 34.7 |
| Σ t-O3-/O2-Araf | 36.9 | 42.6 | 42.5 | 41.6 | 43.8 | 40.7 | 41.5 | 36.6 | 40.8 | 39.3 | 41.3 | 41.3 | 38.9 | 36.8 |
| 1,2,5-Araf | 3.8 | 3.9 | 1.3 | 5.6 | 2.5 | 3.2 | 1.1 | 1.3 | 2.7 | 1.2 | 2.8 | 2.4 | 3.9 | 3.0 |
| 1,3,5-Araf | 13.6 | 11.3 | 29.9 | 9.9 | 12.8 | 14.3 | 19.7 | 22.3 | 16.1 | 21.6 | 22.3 | 17.6 | 12.8 | 17.5 |
| 1,2,3,5-Araf | 9.6 | 11.1 | 6.5 | 9.1 | 9.3 | 9.8 | 7.8 | 6.2 | 10.0 | 7.0 | 7.5 | 7.6 | 10.9 | 7.9 |
| t-β-Araf | 1.6 | 1.0 | – | – | – | – | – | – | – | 1.0 | – | – | – | – |
| After storage | ||||||||||||||
| 5-/1,5-Araf | 34.5 | 23.7 | 27.9 | 25.8 | 27.4 | 23.0 | 30.2 | 31.1 | ||||||
| t-O5-Araf | 21.1 | 16.2 | 15.9 | 20.0 | 17.9 | 13.4 | 23.8 | 18.7 | ||||||
| t-O2-Araf | 7.6 | 14.8 | 5.7 | 11.9 | 7.2 | 10.4 | 10.9 | 10.7 | ||||||
| t-O3-Araf | 15.3 | 21.2 | 22.2 | 20.8 | 20.5 | 25.1 | 14.7 | 18.8 | ||||||
| Σ 5-/1,5-/t-O5-Araf | 55.5 | 40.0 | 43.8 | 45.7 | 45.4 | 36.4 | 54.0 | 49.8 | ||||||
| Σ t-O3-/t-O2-Araf | 22.9 | 36.1 | 27.9 | 32.6 | 27.7 | 35.5 | 25.6 | 29.5 | ||||||
| 1,2,5-Araf | 3.5 | 4.0 | 2.0 | 2.8 | 2.1 | 1.5 | 4.6 | – | ||||||
| 1,3,5-Araf | 10.2 | 10.5 | 22.4 | 12.6 | 17.9 | 21.4 | 12.4 | 17.8 | ||||||
| 1,2,3,5-Araf | 3.6 | 8.5 | 3.9 | 6.3 | 4.9 | 5.2 | 3.4 | 2.9 | ||||||
| t-β-Araf | 4.3 | 1.0 | – | – | 1.9 | – | – | – | ||||||
An exemplary HSQC spectrum with some of the detected structural elements is shown in Figure 2. All analyses were performed in duplicate (technical replicates, each sample was pooled from at least 20 fruits); relative half range uncertainties were mostly < 10%. A = Galiwa, B = Pinova Evelina, C = Elstar v. d. Zalm, D = Ladina, E = Red Topaz, F = PRI 037, G = Gemini, H = Zari, I = PRI 010, J = Crimson Crisp, K = Isaaq, L = Allurel, M = Natyra, N = Lubera, t = terminal, Ara = arabinose, f = furanose. The portions (in %) of some structural elements are listed summarized and individually. Numbers indicate the substituted positions of a sugar unit and O2/O3/O5 indicates the position to which a terminal residue is attached.