Journal of Food and Nutrition Research, 2017, Vol. 5, No. 1, 27-30 Available online at http://pubs.sciepub.com/jfnr/5/1/5 ©Science and Education Publishing DOI:10.12691/jfnr-5-1-5 Omega-3, 6 and 9 Fatty Acids Composition and Lipid Content from Liver and Muscle Tissues of Spiny Lobster (Panulirus homarus) in the Persian Gulf Keivandokht Samiee 1,* , Abdolhossein Rustaiyan 2 , Farnaz Keshavarz 3 1 Faculty of Biological Sciences, Shahid Beheshti University, Tehran, Iran 2 Department of Chemistry, Science & Research Branch, Islamic Azad University, P.O. Box 14515-775, Tehran, Iran 3 Department of Marine Sciences and Technology, Science & Research Branch, Islamic Azad University, Tehran, Iran *Corresponding author: k.samiee@yahoo.com Abstract In this investigation, the liver and muscle tissues of Panulirus homarus from Bushehr region in the Persian Gulf in Aug 2013 were separately extracted for their lipid content especially omega-3, 6 and 9 fatty acids composition using the method of Blight & Dyer. The compounds were determined by Gas Chromatography-Mass Spectrometry (GC- MS). The components detected in the liver and muscle tissues, include saturated fatty acid Palmitic acid, monounsaturated fatty acid Oleic acid, polyunsaturated fatty acids Arachidonic acid (AA), Docosahexaenoic acid (DHA) and Eicosapentaenoic acid (EPA), andone methyl ester of fatty acids including Octadecanoic acid, methyl ester. The results showed that Eicosapentaenoic acid and Palmitic acid were the composition dominant fatty acids in the species. Keywords: Omega-3, Omega-6, Omega-9, lipid content, liver, muscle, Panulirus homarus, Persian Gulf Cite This Article: Keivandokht Samiee, Abdolhossein Rustaiyan, and Farnaz Keshavarz, “Omega-3, 6 and 9 Fatty Acids Composition and Lipid Content from Liver and Muscle Tissues of Spiny Lobster (Panulirus homarus) in the Persian Gulf.” Journal of Food and Nutrition Research, vol. 5, no. 1 (2017): 27-30. doi: 10.12691/jfnr-5-1-5. 1. Introduction Panulirus homarus is a species of spiny lobster that lives along the coasts of the Indian and Pacific Oceans. It lives in shallow water, and feeds on the brown mussel Perna perna. It typically grows to a length of 20–25 cm [5]. The body of Panulirus homarus can reach up to 31 centimeters in total length, or a carapace length of 12 cm, but the average is around 20–25 cm [7]. This species is the most important lobster fishery of Asia. Bodycylindrical comprising cephalothoraxes, heavily spined and conspicuously marked by two frontal supra-orbital horns; abdomen smoother, having six somites; no distinct rostrum. Large antennae particularly large; basal segments well developed and spined; flagellum stiff, robust and longer than body [30] (Figure 1). Figure 1. Panulirus homarus Fatty acids (FA) are long-chain carboxylic acids that are insoluble in water. These fatty acid chains can be from 4 to 30 carbons long, but physiologically the most important fatty acids are from 16 to 22 carbons long [11]. In animals, most fatty acids with 16 or more carbons belong to one of three main fatty acid families [2]. All unsaturated members of a family are n-3, n-6, or n-9. Members of these FA families are not inter-convertible [1]. Omega-3 fatty acids are polyunsaturated fatty acids with a double bond (C=C) at the third carbon atom from the end of the carbon chain [18]. The three types of omega-3 fatty acids involved in human physiology are alpha-linolenic acid (ALA) (found in plant oils), EPA, and DHA (both commonly found in marine oils).Omega-6 fatty acids are a family of polyunsaturated fatty acids that have in common a final carbon-carbon double bond in the n-6 position, that is, the sixth bond, counting from the methyl end. There are several different types of omega-6 fatty acids. Most omega-6 fatty acids in the diet come from vegetable oils, such as linoleic acid (LA). Linoleic acid is converted to gamma-linolenic acid (GLA) in the body. It is then further broken down to arachidonic acid (AA). Arachidonic acid (AA, sometimes ARA) is a polyunsaturated omega-6 fatty acid 20:4(ω-6). Arachidonic acid is not one of the essential fatty acids. However, it does become essential if there is a deficiency in linoleic acid or if there is an inability to convert linoleic acid to arachidonic acid, Arachidonic acid is a precursor in the production of eicosanoids [9,25]. Omega-9 fatty acids are a family of unsaturated fatty acids which have in common a final