Proximate and fatty acid composition of Hetrobranchus longifilis Valenciennes, 1840, oil extract from Oguta waterside, Oguta Lake, Imo State, Nigeria

The Heterobranchus longifilis oil extract obtained from Oguta water side in Oguta Local Government Area, Imo State, Nigeria, was analyzed for the proximate and fatty acid composition. A mature Heterobranchus longifilis weighing 2 kg was purchased from the Oguta water side at Oguta Local Government Area and was used for the analysis. The result of the proximate composition were as follows; Moisture 74.511 0.66, Protein 12.435 0.457, Fat 2.222 0.059, Ash 2.407 0.083, Carbohydrate 7.800 0.915 and Fibre 0.624 0.23. This showed that oil from Heterobranchus longifilis is rich in crude protein, lipid, moisture and ash, as well; meet the requirements for human nutritional needs. Furthermore, oil in the muscle, of the fish were extracted using the Soxhlet apparatus of lipid extraction and were analyzed by gas chromatography to determine the composition of the fatty acid present. A total of nine (9) different fatty acids from the twelve(12) that were analyzed, were found to be present at varying degrees in the fish muscle and they include Docosahexanoic acid (2.410 0.163), Palmitic acid (7.219 0.064), Lauric acid (0.056 0.008), Linolenic acid (28.721 0.945), Arachidonic acid (0.079 0.004), Gondioc acid (5.441 0.043), Stearic acid (37.244 0.622), Linoleic acid (13.111 0.601) and Nervonic acid (5.989 0.099).Stearic acid and Gondoic acid were the main saturated and monounsaturated fatty acids whereas the principal acids in the polyunsaturated groups, are Linoleic and Decosahexanoic acids. The study therefore revealed that Heterobranchus longifilis oil is a rich source of protein and lipid which polyunsaturated fatty acids mainly constitute. It is therefore recommended that fish oil extract, especially tha from Heterobranchus longifilis, should be incorporated into human nutrition as it is good for human nutrition as well as fish meal.