58
COOH
OOH
COOH
COOH
COOH
COOH
COOH
13(R)-HETE
AA
(12S)-LOX
15-LOX
9-LOX
8-LOX
BAH
11-LOX
OH
COOH
OH
9,15-DiHETE
OH
OH
OH
OH
COOH
COOH
HPL
HPL
DES
AOS
15-LOX
AOS
Peroxidase
Peroxidase
Peroxidase
COX
Hydroperoxide
isomerase
Peroxidase Epoxidase
COOH
O
O
O
(E)-2-Nonenal
OH
O
O
COOH
COOH
HO
COOH
HOO
HO
OHH +
O
OH OH
COO
COOH 15-HpETE
OOH
OOH
n-Hexanal
15-Keto PGE2
O
O
O
OOH
HOO
COOH
COOH
HO
COOH
AOS/AOC
OH
PGA2
HO
OH
COOH
11-HETE
COOH
COOH
12(S)-HpETE
8(S)-HpETE
5(R)-HETE
5(R)-HpETE
(5R)-LOX
(5R,6S)-DiHETE
7R-hydroxy-(8S,9S)-EETE
9(S)-HETE
12(S)-HETE
11,12-DiHETE
11,12-EETE
(Z )-3-Nonenal
9(S)-HpETE
11-HpETE
Fig. 4.3 Eicosanoid pathway in seaweeds. Dashed line in red shows putative reactions (LOX lipoxygenase, AOS allene oxide synthase, AOC allene oxide cyclase, COX cyclooxygenase, DES divinyl
ether synthase). Modified from Andreou and Feussner (2009)
complex oxylipins such as polycyclic oxylipins, cyclopropyl hydroxyeicosanoids,
egregialactones, ecklonialactones, hybridialactones, bicyclic cymathere ethers,
cymatherelactones, and cymatherols, most of which are formed from intramolecular
rearrangements of hydroperoxides of either ALA (C18:3, n-3) or stearidonic acid
(C18:4, n-3) (Choi et al. 2012; Gerwick et al. 1990; Kousaka et al. 2003; Lion et al.
COOH
COOH
13-LOX
9-LOX
COOH
Linoleic acid (LA)
α-Linolenic acid (ALA)
COOH
13-LOX
9-LOX
COOH
COOH
HPL
O
n-Hexa(e)nal
OOH
OOH
OOH
OOH
9-Hydroperoxy-10,12octadecatrienoic acid (9-HpOTrE)
9-Hydroperoxy-10,12octadecadienoic acid (9-HpODE)
13-Hydroperoxy-10,12octadecatrienoic acid (13-HpOTrE)
13-Hydroperoxy-10,12octadecadienoic acid (13-HpODE)
Fig. 4.2 Octadecanoid pathway in seaweeds. Modified from Andreou and Feussner (2009)
P. Kumari