| amino acid | Concentration (mg/L) | Average number of SSE per primary SE | Average number of clusters per primary SE | Average number of SSE per cluster |
| Control medium | 0 | 4.53 ± 0.57 abcde | 0.6 ± 0.11 a | 1.73 ± 0.39 abc |
| Glutamine | 10 | 4.63 ± 0.78 abcde | 0.6 ± 0.12 a | 1.63 ± 0.43 abcd |
| 30 | 6.16 ± 0.48 ab | 0.6 ± 0.11 a | 1.9 ± 0.83 ab | |
| 500 | 5.26 ± 0.75 abc | 0.6 ± 0.13 a | 1.67 ± 0.35 abcd | |
| Asparagine | 10 | 3.93 ± 0.51 cde | 0.5 ± 0.11 ab | 1.23 ± 0.34 bcdefg |
| 30 | 5.13 ± 0.63 abcd | 0.5 ± 0.09 ab | 1.53 ± 0.33 abcdef | |
| 500 | 5.3 ± 0.62 abc | 0.36 ± 0.10 abcd | 1.16 ± 0.36 bcdefg | |
| Arginine | 10 | 3.46 ± 0.55 cdef | 0.36 ± 0.10 abcd | 0.76 ± 0.24 cdefg |
| 30 | 3.97 ± 0.66 cde | 0.26 ± 0.08 bcd | 0.7 ± 0.24 cdefg | |
| 500 | 3.47 ± 0.63 cdef | 0.3 ± 0.08 abcd | 0.8 ± 0.26 cdefg | |
| Methionine | 10 | 3.6 ± 0.51 cde | 0.06 ± 0.04 d | 0.2 ± 0.13 f |
| 30 | 3.6 ± 0.52 cde | 0.23 ± 0.07 bcd | 0.5 ± 0.18 ef | |
| 500 | 1.83 ± 0.31 fg | 0.26 ± 0.08 bcd | 0.4 ± 0.13 f |