Gc fid 7890a gc

Leaf discs (2 cm diameter) were cut from 6 different plants (two plants per replicate). Total lipids were extracted from freeze dried tissue as previously reported (Petrie et al., 2012 (link)), run on a TLC plate (20 cm², Silica gel 60, Merck) and developed using a two-step solvent system. Samples were first run to 12 cm in chloroform:methanol:acetic acid:water (68:22:6:4, v:v:v:v), followed by a second separation in hexane:diethyl ether:acetic acid (70:30:1, v:v:v). TAG, DAG and MAG bands were visualized using iodine vapor and isolated from the silica gel. Fatty acid methyl esters were prepared from each isolated lipid fraction and analyzed by GC-FID (7890A GC, Agilent Technologies, Palo Alto, CA, USA) equipped with a 30 m BPX70 column (SGE, Austin, TX, USA) as described previously (Petrie et al., 2012 (link)). Peaks were integrated with Agilent Technologies ChemStation software (Revion B.04.03).

Arabidopsis thaliana seeds were dried in a dessicator for 24 h and approximately 4 mg of seed were transferred to 2 mL glass vials with Teflon-lined screw caps. Seventy (70) μg of triheptadecanoin (Nu-Chek PREP, Inc., USA) were added to the vial as internal standard. Seed fatty acid methyl esters (FAME) were prepared by adding 0.75 mL of 1 N methanolic HCl (Supelco, Bellefonte, PA, USA) to seed material. The mixture was vortexed briefly and incubated at 80°C for 2 h. After cooling to room temperature, 0.3 mL of 0.9% NaCl (w/v) and 0.3 mL hexane were added to the vial and mixed well for 10 min in a Heidolph Vibramax 110. The FAME was collected and analyzed by GC with a flame ionization detector GC-FID (7890A GC, Agilent Technologies, Palo Alto, CA, USA) equipped with a 30 m BPX70 column (0.25 mm inner diameter, 0.25 mm film thickness, SGE, Austin, TX, USA) as described previously (Zhou et al., 2011 (link)). Peaks were integrated with Agilent Technologies ChemStation software (Rev B.04.03). Total FAME (TFA) were quantified based on the internal standard addition and expressed as a percentage of the SW.

Colwellia psychrerythraea 34H cells were harvested and freeze-dried overnight. Fatty acid methyl esters (FAME) were prepared by direct trans-methylation method [8 (link)]. The FAMEs were analyzed by GC-FID (7890A GC, Agilent Technologies, Palo Alto, CA, USA) equipped with a 30 m BPX70 column (0.25 mm inner diameter, 0.25 μm film thickness, SGE, Austin, Texas, USA). Peaks were integrated with Agilent Technologies ChemStation software. GC–MS analysis was essentially performed according to Zhou et al. [21 (link)]. Dimethyloxazoline (DMOX) derivatives of FAMEs were prepared according to Fay and Richli [22 (link)] to determine the double bond positions. For hydroxyl fatty acids, the FAMEs were further derivatized by trimethylchlorosilane as described [21 (link)] to make trimethylsilyl (TMS) derivatives.