title: n-Nonacosadienes from the marine haptophytes Emiliania huxleyi and Gephyrocapsa oceanica.
abstract: The hydrocarbons in cultures of marine haptophytes Emiliania huxleyi NIES837 and Gephyrocapsa oceanica NIES1315 were analyzed, and nonacosadienes and hentriacontadienes were detected as the major compounds in both strains. C29 and C31 monoenes and di-, tri- and tetra-unsaturated C33 alkenes were also detected as minor compounds but not C37 and C38 alkenes. The positions of the double bonds in the C29 and C31 alkenes were determined by mass spectrometry of their dimethyl disulfide (DMDS) adducts. Among the four C29 alkenes identified, the most abundant isomer was 2,20-nonacosadiene, and the other three compounds were 1,20-nonacosadiene, 3,20-nonacosadiene and 9-nonacosene, respectively. Hitherto, 2,20-nonacosadiene and 3,20-nonacosadiene were unknown to be natural products. The double bond at the n-9 (ω9) position in these C29 alkenes is hypothesized to be derived from precursors of unsaturated fatty acids possessing an n-9 double bond, such as (9Z)-9-octadecenoic acid. Nonacosadienes have the potential for being used as distinct haptophyte biomarkers.
authors.affiliation: Department of Natural History Sciences, Faculty of Science, Hokkaido University, N10W8, Kita-ku, Sapporo 060-0810, Japan; CREST, Japan Science and Technology Agency (JST), N10W8, Kita-ku, Sapporo 060-0810, Japan. Electronic address: hideton@mail.sci.hokudai.ac.jp.
authors.forename: Hideto
authors.initials: H
authors.lastname: Nakamura
authors.affiliation: Department of Natural History Sciences, Faculty of Science, Hokkaido University, N10W8, Kita-ku, Sapporo 060-0810, Japan; CREST, Japan Science and Technology Agency (JST), N10W8, Kita-ku, Sapporo 060-0810, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Sawada
authors.affiliation: Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8572, Japan; CREST, Japan Science and Technology Agency (JST), 1-1-1 Tennodai, Tsukuba 305-8572, Japan.
authors.forename: Hiroya
authors.initials: H
authors.lastname: Araie
authors.affiliation: Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8572, Japan; CREST, Japan Science and Technology Agency (JST), 1-1-1 Tennodai, Tsukuba 305-8572, Japan.
authors.forename: Iwane
authors.initials: I
authors.lastname: Suzuki
authors.affiliation: Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8572, Japan; CREST, Japan Science and Technology Agency (JST), 1-1-1 Tennodai, Tsukuba 305-8572, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Shiraiwa
mesh_terms: D000466:Alkadienes / Q000737:chemistry / Q000302:isolation & purification*; D008401:Gas Chromatography-Mass Spectrometry; D058087:Haptophyta / Q000737:chemistry*; D008386:Marine Biology; D015394:Molecular Structure; D019301:Oleic Acid / Q000737:chemistry; D009829:Oleic Acids; D013237:Stereoisomerism
chemical_list: D000466:Alkadienes; D009829:Oleic Acids; D019301:Oleic Acid; C011459:elaidic acid
keywords: Biomarker; Emiliania huxleyi; Gephyrocapsa oceanica; Haptophyte; Long chain alkene; Noelaerhabdaceae; Nonacosadiene