Folks from India extracted 99.6% pure eicosapentaenoic acid (EPA) using silver ion (argentation) column chromatography from hydrolyzed sardine oil[1].

EPA and DHA (docosahexaenoic acid)¬†are the two main long-chain polyunsaturated fatty acids, also frequently referred to as “omega-3”. These lipids are primarily found in oily fish and shellfish. Some researches theorized that the consumption of the aquatic creatures and, hence, DHA/EPA is a key to the brain development of our prehistoric ancestors some 150,000 years ago[2]. Omega-3s also have been found to reduce the risk of heart disease and stroke.

Chakraborty and Raj concentrated EPA from chemically hydrolyzed sardine oil using urea fractionation with methanol at different temperatures and urea/lipids ratios followed by argentation neutral alumina column chromatography. The urea-fatty acid complexes were analyzed by gas-liquid chromatography and gas chromatography-mass spectroscopy that revealed the highest EPA concentration of 48% was at 4 C and 4:1 urea/fatty acid ratio.

Lipid chemists heavily employ argentation chromatography – a technique that dependents on polar complexes that reversibly form between the silver ions and double bonds of the fatty acyl residues of lipids.

I get the science behind the silver ion chromatography, but what about the smell in the lab? You can only imaging that fish stench that permeates everything in its path and comes home with you on your clothes.

[1] “Eicosapentaenoic Acid Enrichment from Sardine Oil by Argentation Chromatography”, Kajal Chakraborty and R. Paul Raj J. Agric. Food Chem., ASAP Article DOI: 10.1021/jf071407r
[2] “The possible role of long-chain, omega-3 fatty acids in human brain phylogeny”, J G Chamberlain, Perspect Biol Med, 1996 vol. 39 pp. 436-45
“Evidence for the unique function of docosahexaenoic acid during the evolution of the modern hominid brain”, M A Crawford et la., Lipids, 1999 vol. 34 Suppl pp. S39-47

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