Table I.
Glycerol and aromatic and aliphatic suberin and cutin monomers released after acid-catalyzed transesterification of extractive free stem periderm and of three different tissues of seeds of a cotton cultivar with white fibers (St 406)
| Compound | Seed Coat | Chalaza | Stem Periderm | Nucellar Cuticlea |
|---|---|---|---|---|
| μmol/g dry wt | ||||
| Glycerol in the wax fraction | 2.90 | 1.01 | 8.54 | 76.44 |
| Glycerol in the suberin fraction | 2.75 | 0.83 | 73.88 | 6.84 |
| Hydroxycinnamic acids | ||||
| p-Coumaric acid | 1.97 | – | 0.96 | – |
| Caffeic acid | 4.56 | – | 0.51 | 0.02 |
| Ferulic acid | 0.56 | 0.14 | 4.66 | 0.14 |
| 4-Hydroxybenzoic acid | 0.07 | 1.78 | – | – |
| 3,4-Dihydroxybenzoic acid | – | 0.22 | – | – |
| 4-Hydroxy,3-methoxybenzoic acid | 0.13 | – | – | – |
| Total | 7.29 | 2.14 | 6.13 | 0.16 |
| Alkanols | ||||
| C14 | 0.04 | 0.05 | 0.26 | – |
| C20 | – | – | 0.54 | – |
| C22 | 0.54 | – | 8.58 | – |
| C24 | 0.05 | – | 5.90 | – |
| Total | 0.63 | 0.05 | 15.28 | 0 |
| Alkanoic and alkenoic acids | ||||
| C14:0 | – | – | – | 0.12 |
| C16:0 | 0.27 | 0.77 | 1.12 | 3.24 |
| C18:0/1/2/3 | 0.33 | 0.84 | 1.89 | 6.43 |
| C20:0 | – | – | 2.00 | 0.17 |
| C22:0 | 0.16 | 0.32 | 5.93 | 0.26 |
| C24:0 | – | 0.12 | 5.43 | – |
| C26:0 | – | 0.15 | 0.15 | – |
| Total | 0.76 | 2.20 | 16.52 | 10.22 |
| α,ω-Alkane and alkenedioic acids | ||||
| C16:0 | – | 0.02 | 14.54 | 0.05 |
| C18:1 | 0.21 | 0.55 | 32.53 | – |
| C20:0 | – | – | 4.09 | – |
| C22:0 | 0.59 | 0.04 | 2.61 | – |
| C24:0 | 0.06 | 0.06 | 0.09 | – |
| Total | 0.86 | 0.67 | 53.86 | 0.05 |
| α-Hydroxyalkanoic acids | ||||
| C20 | – | 0.06 | – | – |
| C22 | 0.11 | 0.16 | – | – |
| C23 | 0.10 | 0.27 | – | – |
| C24 | 0.23 | 0.43 | 0.27 | – |
| C25 | 0.10 | 0.18 | – | – |
| Total | 0.54 | 1.10 | 0.27 | 0 |
| ω-Hydroxyalkanoic and alkenoic acids | ||||
| C16:0 | 0.06 | 0.02 | 9.44 | 0.37 |
| C18:1 | 0.12 | 0.12 | 25.16 | 2.88 |
| C20:0 | 0.16 | 0.03 | 4.50 | – |
| C22:0 | 1.36 | 0.20 | 9.71 | – |
| C24:0 | 0.09 | 0.14 | 0.63 | – |
| 9 or 10,16-Dihydroxy-hexadecanoic acid | – | – | 3.61 | 0.38 |
| 9,10,18-Trihydroxy-octadecanoic acid | 0.10 | 0.39 | 1.16 | 5.82 |
| Total | 1.89 | 0.91 | 54.21 | 9.45 |
| Coefficient Db | +4.67 | +2.10 | +5.44 | −0.18 |
For comparisons, the glycerol content of the wax fraction is also indicated.
a
Results of a single experiment; the other values correspond to the mean of two independent experiments.
b
Discriminant score D, according to the method of Matzke and Riederer (1991). Negative scores are indicative of cutin and positive scores of suberin.