HPLC ANALYSIS OF n-3 AND n-6 FATTY ACID LEVELS IN RAT SERUM AFTER CHRONIC TREATMENT WITH DIETETIC OILS

ABSTRACT

High-performance liquid chromatography (HPLC) analysis of the major fatty acids of the n-3 family and n-6 family in rat serum was carried out. To perform sample cleanup, existing techniques of lipid extraction were tested and modified to achieve maximal free fatty acids recovery in a reasonable time. Concerning chromatographic analyses, p-bromophenacyl bromide was used as ultraviolet (UV)-derivatizing agent followed by reversed-phase HPLC/UV under mobile phase gradient conditions. The optimized and validated procedure was then applied to rats fed with flaxseed oil and a combination of flaxseed, fish and sunflower oils, defined as “dietetic oil,” in order to evaluate how their chronic supplementation can influence serum levels of n-3 and n-6 fatty acids.

PRACTICAL APPLICATIONS

Rats treated chronically with flaxseed oil and “dietetic oil” (composed of flaxseed, fish and sunflower oils) showed enhanced levels of n-3 fatty acids. In particular, the levels found for α-linolenic acid was a little higher after administration of the dietetic oil, probably due to an enhanced absorption and also a decreased metabolism. The data obtained underline that the tested oils can enhance the levels of n-3 fatty acids and, therefore, they could be successfully used in the dietetic treatment of lipid-related diseases.