Table 1.
A detailed overview of the four lipid extraction protocols used in the present study
| Time for the extraction of 25 samples | Burgos et al. [27] | Hummel et al. [24] | Shiva et al. [23] | Welti et al. [18] |
|---|---|---|---|---|
| Total time | 4 h | 5 h | 4 h + 24 h extraction time | 12 h |
| 1 h | Homogenize with 1 ml of CHCl3/MeOH/water (1:2.5:1) | Homogenize with 1 ml of MeOH:methyl-tert-butyl-ether (1:3) | Homogenize with 400 µl of 2-propanol with 0.01% BHT | Homogenize with 1 ml of 2-propanol with 0.01% BHT |
| 1 h |
Shake for 30 min at 4 °C Spin down for 15 min at 4 °C at 13,200 rpm |
Incubate for 10 min in a shaker at 4 °C Incubate for 10 min in an ultrasonication bath at room temperature Add 500 µl of water: MeOH (3:1) Vortex and centrifuge at 13,200 rpm for 15 min |
Heat the samples at 75 °C while shaking at 1400 rpm for 15 min Cool to room temperature Add 1.2 ml of CHCl3/MeOH/water (30/41.5/3.5, v/v/v) |
Add 0.5 ml CHCl3 and 0.2 ml water Heat at 75 °C while shaking at 1400 rpm for 15 min |
| 1 h | Remove the upper organic phase containing lipids | Shake for 1 h at 1400 rpm at room temperature | ||
| 4 h |
Centrifuge at 1300 rpm for 15 min Re-extract with 0.3 ml of CHCl3/MeOH (2:1) with 0.01% BHT, four times |
|||
| 2 h | Wash the combined extracts once with 0.4 ml of 1 M KCl followed with 0.7 ml of water | |||
| 24 h | Shake for 24 h at 300 rpm and 25 °C | |||
| 2 h | Dry down the organic phase in a SpeedVac | Dry down the organic phase in a SpeedVac | Dry down the solvent in a SpeedVac | Evaporate the solvents by SpeedVac |
BHT butylated-hydroxy-toluene