In search of an accurate and effective method to determine fatty acid
composition in silkworm pupae oils, five methylation methods were evaluated
for use in the gas chromatographic (GC) quantitation of fatty acid methyl
esters (FAMEs), including one-step esterification catalyzed by an acidic
(H2SO4 and BF3) or alkali catalyst (KOH and NaOCH3) and a two-step procedure
catalyzed successively by KOH and H2SO4. These methods were comparatively
adopted to quantify FAMEs in silkworm pupae oil using GC-MS and GC and then
validate their precision, stability and average recovery rates. The results
indicated that compared with the other four methyl esterification methods,
two-step methylation effectively improves the synthesis yield of FAMEs,
conserves agents, and eliminates the usage of potential harmful reagents.
The proposed GC method has been validated, shows good accuracy and
precision, and has been applied successfully to the quantification of FAMEs
in several varieties of silkworm pupae oils. The short analytical run time
leads to low costs and a fast chromatographic procedure. In summary,
two-step pretreatment had superior performance, providing technical
references for the determination and analysis of fatty acids in other oils.
Electrochromic Performance and Capacitor Performance of α-MoO3 Nanorods Fabricated by a One-Step Procedure