178
Y. Olsen
(Pohl, 1982). Although some marine animals are able to elongate shorter co3 and
co6 fatty acids, we know that all co3 and co6 double bonds of fatty acids present in marine systems have been synthesized de novo in marine plants or
bacteria.
The content of co3 fatty acids in marine algae is related to the species (genetic)
and environmental growth conditions (see also Napolitano, this volume). Values
TABLE 8.1. Content of 003 fatty acids (percentage of total fatty acids) in species and
groups of marine phytoplankton."
EPS
DHA
Sum (03
Dinoflagellates (n = 22)
Mean
6.9
23
45
SD
5.6
6
12
Range
0-20
12-34
26-68
Selected species
Amphidinium cartiri
20
24
66
Cryptecodinium cohnii (heterotrophic)
()
30
31
Gvmnodinium sp.
14
32
68
Diatoms (11 = 12)
Mean
14
I
17
SD
7.6
0.8
7.4
Range
7-30
0-4
10-32
Selected specics
Lauderia borealis
30
0
32
Ske/etomema costatum
14
2
IR
Chaetoceros sp.
18
4
25
Phaeodactl'luml ricornlilum
24
4
32
Chrysophytes (n = 13) (covers many taxonomic groups)
Mean
IS
4
30
SD
9.8
4.5
II
Range
0-28
0-17
12-47
Selected species
Svracosphaera carlerae
4
8.6
45
Cocco/ilhu.> hux/ev
17
0
20
lsochrYSis !;a/bwl(l
0.5
17
35
Pew/om /Iltheri
26
I
47
Green algae (n = 14) (covers many taxonomic groups)
Mean
9
0.3
29
SD
12
13
Range
0-40
0-4
3-48
Selected species
Ch/orella minutissima
40
0
41
Telraselmis sp.
]()
0.2
28
Nannochloris atom".>
IS
0.3
22
"n. Number of observations included. Data from review by Olsen (1989) and references therein and
Reitan et al. (1994b).