shows a typical GC chromatogram of a FAME
standard mix containing 52 fatty acids with chain lengths between
C4 and C22 under the optimized conditions. The following characteristics
of retention time concerning position and geometry of
FAs could be found: Rt Cn < Rt Cn þ 1,2,3 .; Rt trans-Cn < Rt cis-Cn.
For instance, 9t C18:1 was eluted before 9c C18:1, 9c 12t C18:2; and
9t 12c C18:2 were eluted prior to 9c 12c C18:2, 9c 12c 15c C18:3.
Under the GC analysis conditions, all FAMEs were adequately
resolved except a partial overlap from C20:0 to 9c 12c 15c C18:3
(Fig. 1A, peak 1e9), which were also reported in the previous
studies