Table 1. Chemical forms of Se found in seeds of S. pinnata and A. bisulcatus.
| SS (x10−4) | SeO3 2− | Se(GSH)2 | C-Se-C | Se0 | |
| S. pinnata | |||||
| 0, 1, 2 embryo, root | 3.3 | 3% | nd | 77% | 19% |
| 3, 4, 5 embryo, cotyledon | 4.1 | 3% | nd | 73% | 24% |
| 6, 7 seed coat | 1.8 | 5% | nd | 77% | 19% |
| 8, 9 embryo, herbivore damage | 3.1 | nd | nd | 100% | nd |
| A. bisulcatus | |||||
| 0 embryo, cotyledon | 3.7 | 3% | nd | 97% | nd |
| 1 embryo, root | 4.0 | 3% | nd | 96% | nd |
| 2 seed coat | 9.8 | 8% | 28% | 63% | nd |
Results from least-squares linear combination fitting of each samples XANES spectra in comparison to standard selenium compounds.
The regions where the spectra were collected are indicated in Figure 1.
SeO3 2−: selenite; Se(GSH)2: seleno-diglutathione, C-Se-C: methyl-selenocysteine, seleno-methionine or seleno-cystathionine.
Se0: red or gray elemental Se. SS: normal sum of squares (quality of fit; 0 = perfect fit); nd: compound not detectable. Additional standard compounds included in the fit but not detected in any location were selenate, seleno-cystine and seleno-cysteine. Note: fractions do not always add up to exactly 100% because the margin of error can be up to10%.