title: High docosahexaenoic acid levels in both neutral and polar lipids of a highly migratory fish: Thunnus tonggol (Bleeker).
abstract: The lipid and FA compositions of various organs (light muscle, dark muscle, liver, pyloric cecum, and the orbital region) and of the stomach contents of a highly migratory fish species Thunnus tonggol (Bleeker) were analyzed. TAG and phospholipids (PE and PC) were the major lipid classes in the total lipids of T. tonggol. DHA was characteristically the major FA of all the major classes of all its organs except for only one case of liver TAG. The mean DHA contents of the various organs accounted for more than 20% of the total FA (TFA), even though it is a neutral depot lipid. However, DHA in the stomach contents, originating from their prey, fluctuated and was generally low. DHA levels were generally higher in a year (2000) when water temperatures were colder than in one when it was warmer (1998). Furthermore, DHA levels in muscle TAG were consistently high in spite of the fluctuation of those in the visceral TAG, which might be directly influenced by the prey lipids. This phenomenon suggests the physiological selective accumulation of DHA in the muscle, after the migration of the digested FA in the vascular system and absorption of the prey lipids in the intestine. In contrast, the FA composition of other species is generally variable and their DHA contents of TAG are usually less than 20% of TFA.
authors.affiliation: National Research Institute of Fisheries Science, Fisheries Research Agency, Yokohama-shi, Japan. hiroakis@affrc.go.jp
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Saito
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Seike
authors.forename: Hisashi
authors.initials: H
authors.lastname: Ioka
authors.forename: Kazufumi
authors.initials: K
authors.lastname: Osako
authors.forename: Mikiko
authors.initials: M
authors.lastname: Tanaka
authors.forename: Akihito
authors.initials: A
authors.lastname: Takashima
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Keriko
authors.forename: Sevim
authors.initials: S
authors.lastname: Kose
authors.forename: Juan C
authors.initials: JC
authors.lastname: Rodriguez Souza
mesh_terms: D025041:Animal Migration; D000818:Animals; D004281:Docosahexaenoic Acids / Q000032:analysis / Q000378:metabolism*; D005227:Fatty Acids / Q000032:analysis; D005753:Gastric Mucosa / Q000378:metabolism; D050356:Lipid Metabolism; D008055:Lipids / Q000737:chemistry*; D009132:Muscles / Q000378:metabolism; D014280:Triglycerides / Q000737:chemistry; D014413:Tuna / Q000378:metabolism* / Q000502:physiology
chemical_list: D005227:Fatty Acids; D008055:Lipids; D014280:Triglycerides; D004281:Docosahexaenoic Acids