Analysis of fatty acid composition and total oil in different flaxseed (Linum usitatissimum) genotypes

Abstract

Linum usitatissimum (Linn.), commonly known as flaxseed or linseed, belongs to the family Linaceae. Flaxseed has high nutritive value and multiple uses. It is considered a functional food that has nutrients with specific properties, such as essential omega-3 fatty acids (a-linolenic acid, 18:3n3), lignan or dietary fibers. Additionally, a-linolenic acid (ALA) is the precursor of the polyunsaturated fatty acids (PUFA) omega-3 family which forms eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the body. The converting of ALA to EPA and DHA in the body is restricted, but can be physiologically and clinically important. Flaxseed is regarded as the best plant source of the essential omega-3 fatty acid. Studies suggest that the omega-3 fatty acid may have anticancer properties. Hence, present study is carried out to compare content of essential fatty acids in six different flaxseed genotypes. The oily flax type was exclusively included in this assay. In 2017, field experiment was conducted on the location of Rimski Sanéevi (Vojvodina Province, Serbia). Oil content was obtained by extracting samples in a soxhlet apparatus using petroleum ether as the extractant. Trimethylsilyl esters of fatty acids were determined from oil of flaxseed by using capillary gas chromatography with a flame ionisation detector. Total oil contents at flaxseed varied among 37.49-45.87% for tested genotypes. Gas chromatography analyses showed major fatty acids to be a-linolenic acid, linoleic and oleic acids. The content of 18:3n3, 18:2n6 and oleic acids were within the ranges of 52.61-58.65%, 13.29-21.71% and 16.41-20.52% of the total fatty acids, respectively. The study confirmed that the essential fatty acids (18:2n6 and 18:3n3) are predominant acids in investigated genotypes of flaxseed. The presence of essential fatty acids in tested flaxseed genotypes makes them nutritionally valuable. The results have shown that there were differences in content of essential fatty acids among the genotypes, indicating the great genetic potential for further improvement.