Non-Methylene-Interrupted Polyenoic Fatty Acids

The Author: Frank D. Gunstone, James Hutton Institute (and Mylnefield Lipid Analysis), Invergowrie, Dundee (DD2 5DA), Scotland

The most common non-methylene interrupted polyenes (NMIP) are acids with n-9, n-6, or n-3 unsaturation and an additional double bond at Δ5 which commonly has the cis configuration but is sometimes trans. Acids of this type include taxoleic (5c,9c-18:2), pinolenic (5c,9c,12c-18:3), columbinic (5t,9c,11c-18:3), podocarpic or sciadonic (5c,11c,14c-20:3), and juniperonic (5c,11c,14c,17c-20:4).

Table 1

 16:2 (5c,9c)18:2 (5c,9c)19:2 (5c,9c)20:2 (5c,9c)18:2 (5t,9c)
1 180.3 174.2 180.2 179.7 174.15
2 33.4 33.55 33.4 nc 33.45
3 24.5 24.98 24.5 nc 24.85
4 26.4 26.68 27.4 27.3 32.00
5 128.6 128.84 130.6 130.6 129.40
6 130.58 130.54 130.5 130.5 131.15
7 27.2 27.39 27.2 27.3 32.75
8 27.2 27.39 27.2 27.3 27.35
9 128.9 129.98 128.9 128.9 129.10
10 130.51 130.48 128.6 128.8 130.45
11 27.4 27.48 26.5 nc 27.35
12 29.7 29.82 29.7 nc 29.80
 
ω3 31.7 32.00 31.9 31.9 32.00
ω2 22.6 22.78 22.7 nc 22.75
ω1 14.1 14.18 14.1 nc 14.10
nc = not cited.
The C18 compounds are methyl esters; the remainder are acids.
Carballeira et al. (1999) did not assign all the chemical shifts. Most have been assigned by the author of this paper on the basis of other shifts in this Table.
 

Table 2
 5,11,14-20:35,11,14,17-20:4
 MeGl (α)MeGl (α)
1 174.15 173.05 174.15 173.05
2 33.54 33.43 33.55 33.43
3 25.00 24.81 25.00 24.81
4 26.68 26.52 26.64 26.52
5 128.49 128.35 128.48 128.37
6 130.92 131.05 130.92 131.03
7 27.21 27.16* 27.23 27.16*
8 29.43 nc 29.39 nc
9 29.43 nc 29.39 nc
10 27.23 27.15* 27.23 27.15*
11 130.21 129.89 130.13 130.11
12 128.16 128.17 127.79 127.83
13 25.76 25.64 25.70 25.64
14 128.16 127.91 128.26 128.23
15 130.21 # 128.26 #
16 27.23 nc 25.70 25.55
17 29.43 nc 127.19 #
18 31.64 31.55 131.95 131.93
19 22.68 32.61 20.66 20.57
20 14.16 14.10 14.39 14.30

*Signals may be exchanged, # overlapping signals, nc, not cited.
Some of the other signals overlap with those of linoleic or linolenic esters.
Me, methyl esters (Gunstone,); Gl, glycerol esters (Lie Ken Jie and Mustafa, 1997; Lie Ken Jie et al., 1996).

References

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  • Gerson, M.J., Zimmermann, M.P., Hoberg, M., Larsen, R.M., Battershill, C.N. and Murphy, P.T. Isolation of brominated long-chain fatty acids from the phospholipids of the tropical marine sponge Amphimedon terpenensis. Lipids, 28, 1011-1014 (1993).
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