The chemical composition, fatty acid, amino acid profiles and minerals content of six fish species commercialized on the Wouri river coast in Cameroon

The chemical composition and nutritional qualities of fats and proteins of six species of fish: Herring (Clupea Harengus), Belt (Trichius Lepterus), Catfish (Arius Maculatus), Red carp (Cyprinus Carpio), Disc (Symphysadon Discus) and Mullet (Semotilus atromaculatus) were investigated. The investigation showed that the chemical composition of fish is not the same in all species. The total protein content of the species is higher than 64.2%. The total lipid content was generally high, ranging from 8.9% to 23.0% and crude ash ranged from 10.7% to 19.4%. The most abundant fatty acids in all the species were saturated fatty acids (45.5 - 54.9%) and palmitic acid was the predominant saturated fatty acid in all these fish (C16:0: 26.7 - 34.0%). After saturated fatty acids, monounsaturated fatty acid was the second predominant fatty acid (26.7 - 36.9%) and oleic acid was the most abundant monounsaturated fatty acid in all these fish. Moreover, these fish contained reasonable amounts of essential polyunsaturated fatty acid (PUFA) such as docosahexaenoic, eicosapentaenoic, and arachidonic acids. The data revealed that all these fish were a good source of omega-3 PUFA ranging from 9.8% to 14.7%. Catfish contained the highest amounts of PUFA (20.9%). The lower level of omega-6 in these fish suggested that these fish especially Belt and Catfish, could be used as a source for a healthy diet for humans. All these fish contained 17 known amino acids, including all of the essential amino acids. The most abundant amino acids were glutamic acid (161.5 to 190.3 mg/g of protein), aspartic acid (108.6 to 148.2 mg/g of protein), glycine (52.7 to 70.8 mg/g of protein), arginine (42.5 to 57.6 mg/g of protein), proline (57.7 to 81.9 mg/g of protein), isoleucine (59.5 to 93.0 mg/g of protein), leucine (83.4 to 102.1 mg/g of protein), and lysine (60.5 to 74.7 mg/g of protein). The mineral analysis indicated high Ca, K and Mg content.