Table 2.
Seasonal changes in the FA composition of lipids in shoots of Equisetum scirpoides growing at the Pole of Cold.
| Summer Period (+17.8 °C *) | Autumn Period (+0.6 °C *) | Winter Period (−46.7 °C *) | ||||
|---|---|---|---|---|---|---|
| Fatty Acids | ||||||
| mg/g DW | % | mg/g DW | % | mg/g DW | % | |
| C12:0 | traces | 0.3 ± 0.0 a | traces | 0.2 ± 0.0 a | – | – |
| C14:0 | 0.2 ± 0.0 a | 1.3 ± 0.2 a | 0.1 ± 0.0 a | 0.8 ± 0.1 a | 0.1 ± 0.0 a | 0.7 ± 0.1 a |
| C15:0 | traces | 0.3 ± 0.0 a | 0.1 ± 0.0 a | 0.3 ± 0.0 b | – | – |
| C16:0 | 2.7 ± 0.9 a | 21.1 ± 1.2 c | 3.9 ± 0.9 a | 22.6 ± 1.6 c | 5.9 ± 1.1 b | 31.3 ± 2.3 c |
| C16:1 | 0.1 ± 0.0 a | 1 ± 0.2 a | 0.2 ± 0.0 a | 1.4 ± 0.6 a | traces | 0.2 ± 0.0 a |
| C16:2(n-6) | 0.1 ± 0.0 a | 0.7 ± 0.1 a | 0.2 ± 0.0 c | 1.2 ± 0.5 a | – | – |
| C16:3(Δ7,11,14) | 0.3 ± 0.0 a | 2.6 ± 0.9 b | 1.0 ± 0.2 a | 5.7 ± 1.1 c | 1 ± 0.4 a | 5.2 ± 1.4 b |
| C17:0 | 0.1 ± 0.0 a | 0.7 ± 0.1 a | 0.1 ± 0.0 b | 0.3 ± 0.0 a | 0.1 ± 0.0 a | 0.6 ± 0.2 a |
| C18:0 | 0.7 ± 0.1 a | 5.2 ± 1.1 c | 0.3 ± 0.0 a | 1.8 ± 0.3 a | 0.3 ± 0.0 a | 1.8 ± 0.4 a |
| C18:1(n-9) | 0.8 ± 0.1 a | 6.1 ± 1.4 c | 0.6 ± 0.0 a | 3.7 ± 1.3 c | 0.9 ± 0.2 b | 4.8 ± 1.1 c |
| C18:1(n-7) | 0.1 ± 0.0 a | 0.6 ± 0.1 a | 0.1 ± 0.0 a | 0.3 ± 0.0 a | 0.1 ± 0.0 a | 0.3 ± 0.0 a |
| C18:2 (Δ5,9) | 0.7 ± 0.2 a | 5.8 ± 0.9 b | 0.5 ± 0.1 a | 3.1 ± 0.8 a | 0.5 ± 0.0 a | 2.4 ± 0.6 a |
| C18:2(n-6) | 2.0 ± 0.4 b | 16.1 ± 1.4 c | 2.3 ± 0.6 b | 13.1 ± 1.1 c | 3.6 ± 0.8 b | 18.8 ± 1.4 c |
| C18:3(n-3) | 4.0 ± 0.9 c | 31.4 ± 1.6 c | 6.5 ± 1.0 c | 37.5 ± 2.7 c | 5.9 ± 1.1 c | 31 ± 1.9 c |
| C20:0 | 0.1 ± 0.0 b | 0.8 ± 0.1 a | traces | 0.2 ± 0.0 b | 0.1 ± 0.0 a | 0.5 ± 0.0 a |
| C20:1(n-9) | traces | 0.1 ± 0.0 a | traces | 0.1 ± 0.0 b | – | – |
| C20:3(Δ11,14,17) | 0.4 ± 0.1 a | 2.8 ± 0.7 b | 0.6 ± 0.1 a | 3.7 ± 1.1 c | traces | 0.2 ± 0.0 a |
| C20:4(Δ5,11,14,17) | 0.3 ± 0.0 b | 2.2 ± 0.6 b | 0.6 ± 0.1 a | 3.4 ± 1.3 b | 0.3 ± 0.0 a | 1.7 ± 0.3 a |
| C22:0 | 0.1 ± 0.0 a | 0.8 ± 0.2 a | 0.1 ± 0.0 a | 0.5 ± 0.1 a | 0.1 ± 0.0 a | 0.5 ± 0.1 a |
| Total FAs | 12.6 ± 1.2 a | 100 | 17.2 ±1.4 c | 100 | 18.9 ± 1.2 b | 100 |
| Σsaturated | 3.8 ± 0.8 b | 30.5 ± 1.3 c | 4.6 ± 0.9 b | 26.7 ± 1.9 a | 6.7 ± 1.2 b | 35.4 ± 3.2 c |
| Σunsaturated | 8.7 ± 0.9 b | 69.4 ± 1.9 c | 12.6 ± 1.3 c | 73.2 ± 2.2 c | 12.2 ± 2.3 c | 64.6 ± 3.4 c |
| k | 2.3 | 2.7 | 1.8 | |||
| DBI | 1.8 | 1.8 | 1.6 | |||
| SDR | 0.7 | 0.6 | 0.7 | |||
| ODR | 0.9 | 0.9 | 0.9 | |||
| LDR | 0.7 | 0.7 | 0.6 | |||
Note: “–”—acid not found; *—mean daily air temperature; Σsaturated—the sum of saturated FAs; Σunsaturated—the sum of unsaturated FAs; k—unsaturation coefficient; DBI—FA double-bond index. The table shows the average values from 3–6 biological replicates and their standard deviations. The significance of differences between the compared mean values was assessed using the t-test (p < 0.05), the normal distribution hypothesis was tested using the Shapiro–Wilk test. Different superscript letters indicate significant differences of analyzed parameters.