Chemical composition of lipids from native and exotic fish in reservoirs of the state of Ceará, Brazil

ABSTRACT Current study analyzes the chemical composition of lipids in fish commonly found in the dams of the state of Ceará, Brazil, namely Pterygoplichthys pardalis (bodó), Hoplias malabaricus (traira), Cichla ocellaris (tucunaré), Prochilodus brevis (curimatã) and Oreochomis niloticus (tilapia). The animals were collected during the summer and Folch extraction procedure was used for the extraction of lipids, whilst Iupac methodology (International Union of Pure and Applied Chemistry [Iupac], 1987) was used to methylate the fatty acids. Methyl esters were analyzed by GC/MS and the different components in fish oil were identified. Palmitic acid, C16:0 (35.71-45.02%), was the saturated fatty acid with the highest percentage, while oleic acid, C18:1Δ9 (10.62-25.29%) had the highest percentage among the unsaturated fatty acids. The chemical composition of analyzed freshwater fish lipids revealed low levels of polyunsaturated fatty acids.

摘要 本研究分析了巴西塞阿拉州水库常见鱼类的脂质化学成分，受试鱼种分别为豹纹翼甲鲶（Pterygoplichthys pardalis，俗称bodó）、马拉巴狼牙脂鲤（Hoplias malabaricus，俗称traira）、眼斑丽鱼（Cichla ocellaris，俗称tucunaré）、短头鲮脂鲤（Prochilodus brevis，俗称curimatã）以及尼罗罗非鱼（Oreochromis niloticus，俗称tilapia）。实验所用鱼类样本于夏季采集，采用弗奇萃取法（Folch extraction）提取脂质，依照国际纯粹与应用化学联合会（International Union of Pure and Applied Chemistry, IUPAC）1987年发布的方法对脂肪酸进行甲酯化处理。通过气相色谱-质谱联用仪（Gas Chromatography-Mass Spectrometry, GC/MS）对脂肪酸甲酯进行分析，鉴定出鱼油中的各类组分。其中饱和脂肪酸中棕榈酸（C16:0）占比最高，为35.71%~45.02%；不饱和脂肪酸中油酸（C18:1Δ9）占比最高，为10.62%~25.29%。本次分析的淡水鱼脂质化学成分显示，其多不饱和脂肪酸含量偏低。