| The fatty acid (FA) analysis of microalgae Spirulina was studied by application of accelerated solvent extraction (ASE) followed by purification by solid-phase extraction (SPE) and GC-MS analysis. The objective of this study was to develop a sensitive and reliable purification step to remove pigment contaminants in lipids which co-extracted from Spirulina sample. Four extraction solvents were used to the ASE for lipids extraction, extraction efficiency followed as chloroform:methanol> dichloromethane:methanol> ethanol> hexane. The major composition of fatty acids were considered, two extraction solvents were compared, and the amounts of sorbent (Silica gel H) and sample, and the volume of eluent were optimized during SPE procedure. Result showed that, the purification step can successfully remove the pigments from extracted lipids. For hexane as the extraction solvent,0.5g sample,0.3g silica gel is the optimal amount of sorbent,5mL is the optimal volume of eluent. For0.1g sample, chloroform/methanol (2:1, v/v) is the optimal extraction solvent,0.3g silica gel is the optimal amount of sorbent, and7mL for the volume of eluent for the purification step. The recovery of this method was also studied, the result showed that the recoveries of fatty acids are found to be67.97-134.37%,74.20-99.13%and98.34-115.42%, respectively. Overall, the recovery is stable and well reproducible.Additionally, we also compared the separation of37mixed fatty acid methyl esters by DB-Wax, DB-5ms, VF-23ms three capillary columns. The result showed that DB-Wax column has the higher bleeding, not suitable for GC-MS analysis, and does not fit for the detection of fatty acids. DB-5ms can not separate the fatty acid methyl esters completely. While VF-23ms can seprated37mixed fatty acid methyl esters successfully. The method is useful for other related researches. |
PDF Full Text Request