Component fatty acids of marine fish liver oils

Abstract

Summary1. Two liver oils (Elasmobranch) fromCarcharias melanopterus andPristis cuspidatus, caught off the Madras coast are studied, and their component fatty acids are reported.2. The mixed acids were separated into three groups (varying unsaturation) of acids, and their methylesters were fractionated.3. The liver oils are found to belong to the fourth group of Tsujimoto’s classification of Elasmobranch fish liver oils.Carcharias melanopterus liver oil contains 31.1% unsaturated acids (myristic 3.1, palmitic 18.4, stearic 9.5, and 0.1% arachidic) and 68.9% unsaturated acids (C16 10.8, C18 19.7, C20 15.2, C22 17.1, C24 5.3%, and traces of C14 monoethenoid).Pristis cuspidatus liver oil contains 36.9% saturated acids (myristic 1.2, palmitic 22.9, stearic 12.7, and arachidic 0.1%) and 67.1% unsaturated acids (C16 8.2, C18 28.5, C20 16.4, C22 5.2, C24 4.6%, and traces of C14 monoethenoid). The unsaturations of the different groups of acids are almost of the same order.4. The abnormal content of saturated acids can be explained by the process of bio‐hydrogenation. The relatively less amount of saturated acids inCarcharias melanopterus liver oil along with its higher content of polyethylenic acids (C20 and above) points strongly to the possible presence of intermediate types of fats among the four groups of Elasmobranch oils.