Comparative assessment for efficiency of isolation of arachidonic acid (20:4n-6) from various sources

Abstract

Methods of arachidonic acid (AA) isolation from animal and vegetal natural sources are considered. Traditional raw material as the lipids of beef liver and alternative source as the red alga Gracilaria vermiculophylla are tested. The AA was isolated by a sequence of known techniques for concentration of polyunsaturated fatty acids: sedimentation of saturated fatty acids in the form of their lithium salts, iodo-lactonization, and high performance liquid chromatography. All these techniques were applied for isolation of AA from the beef liver lipids, where the AA content did not exceed 7.7 % of total lipids, and the yield of AA with purity of 98.76 % was 50.8 %. The AA content in the algae lipids was significantly higher (> 35 %), while the amount of n-3 polyunsaturated fatty acids was insignificant, so two techniques only were applied (sedimentation of lithium salts and liquid chromatography), and the yield of AA with purity of 97.60 % was 68.3 %. Thus, high-purity arachidonic acid could be isolated from the algae G. vermiculophylla using simple and reproducible procedure. Taking into account the high yield of AA, this method is economically feasible and is proposed for biochemical and medical researches.