Determining double-bond positions in monoenoic 2-hydroxy fatty acids of glucosylceramides by gas chromatography-mass spectrometry.
We applied a gas chromatography-mass spectrometry (GC-MS) method using dimethyl disulfide (DMDS) adducts and were able to determine the double-bond positions in monounsaturated 2-hydroxy fatty acids (2-HFA). 2-HFA methyl esters, prepared from the hydrolysate of Arabidopsis thaliana leaf glucosylceramides, were acetylated and methylthiolated. GC-MS analysis of the resulting DMDS adducts showed simple mass spectra with recognizable molecular ions and a series of key fragment ions indicating the original double-bond positions in the aliphatic chain. Based on this GC-MS elucidation, we confirmed that Arabidopsis leaf glucosylceramides have C22, C23, C24, C25, and C26 chain length 2-HFA with monounsaturation, and all their double bonds are placed at the n-9 position. This procedure is simple, time efficient, and highly sensitive.
Imai
H
H
Department of Biology, Faculty of Science, Konan University, Kobe, Japan.
Yamamoto
K
K
Shibahara
A
A
Miyatani
S
S
Nakayama
T
T
D017360:Arabidopsis / Q000737:chemistry; D004220:Disulfides / Q000737:chemistry; D005227:Fatty Acids / Q000032:analysis / Q000737:chemistry*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D005963:Glucosylceramides / Q000032:analysis / Q000737:chemistry*
D004220:Disulfides; D005227:Fatty Acids; D005963:Glucosylceramides; C021181:dimethyl disulfide