title: Regiospecific distribution of fatty acids in triacylglycerols of Artemia franciscana nauplii enriched with fatty acid ethyl esters.
abstract: This paper reports the positional distribution of fatty acids in triacylglycerols (TAG) of Artemia franciscana nauplii enriched with each of palmitic (16:0), oleic (18:1n-9), linoleic (18:2n-6), linolenic (18:3n-3), eicosapentaenoic (20:5n-3), and docosahexaenoic (22:6n-3) acid ethyl esters. TAG extracted from the enriched and unenriched nauplii were subjected to regiospecific analysis to determine the fatty acid compositions of the sn-1(3) and sn-2 positions of TAG. In the unenriched nauplii, 16:0, 18:1n-9, and 18:2n-6 were preferentially located in the sn-1(3) position followed by the sn-2 position [i.e. sn-1(3)>sn-2], whereas 18:3n-3 was concentrated in the sn-2 position [i.e. sn-2>sn-1(3)]. Contents of 20:5n-3 and 22:6n-3 were low. After the nauplii were enriched with each of the ethyl esters for 18 h, fatty acid fed to the nauplii showed higher content in the sn-1(3) position than in the sn-2 position [i.e. sn-1(3)>sn-2]. Distribution pattern of 18:3n-3 changed from sn-2>sn-1(3) to sn-1(3)>sn-2 during the enrichment with 18:3n-3 ethyl ester. Increases in all of the fatty acids in TAG were attributed to that in the sn-1(3) position much more than that in the sn-2 position. Artemia nauplii appear to be characterized by preferential incorporation of exogenous fatty acids into the sn-1(3) position of TAG, even though endogenous fatty acids are esterified in the opposite position.
authors.affiliation: Laboratory of Bioresources Chemistry, Division of Marine Biosciences, Graduate School of Fisheries Sciences, Hokkaido University, Hakodate 041-8611, Japan. ando@fish.hokudai.ac.jp
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Ando
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Oomi
authors.forename: Keiichi
authors.initials: K
authors.lastname: Narukawa
mesh_terms: D000818:Animals; D001156:Artemia / Q000737:chemistry*; D004032:Diet; D004952:Esters; D005227:Fatty Acids / Q000032:analysis / Q000378:metabolism*; D014280:Triglycerides / Q000032:analysis / Q000737:chemistry*
chemical_list: D004952:Esters; D005227:Fatty Acids; D014280:Triglycerides