the sea star Acanthaster planci (Itakura and Komori 1986), were purified from the
sea star L. ludwigi scotti (Roccatagliata 1996). Versicoside A, an asterosaponin
from Asterias amurensis versicolor (Itakura et al. 1983), was also purified with
Anasterosides A and B from A. minuta (Maier et al. 2002).
Polyhydroxysteroids are also extracted from echinoderms. These compounds
show a polyhydroxylated steroidal aglycone and one or two monosaccharide
moieties with variability in the hydroxylation pattern, the side chain functionalization, the localization of the glycosidic link and the presence of the sulfate
moiety. Two novel steroidal xyloside sulfates (Luridosides A and B) and the
known Pycnopodioside C, previously isolated from Pycnopodia helianthoides
(Bruno et al. 1989), were isolated from the sea star C. lurida (Maier et al. 1993).
Anasterias minuta provided two new sulfated polyhydroxylated steroidal xylosides: Minutosides A and B, together with the known Pycnopodioside B, previously isolated from P. helianthoides (Bruno et al. 1989). Minutoside B is the first
example of a polyhydroxylated steroidal xyloside containing an amide function in
the aglycone side chain (Fig. 11.5b). The three xylosides from A. minuta exhibited
antifungal activity against Cladosporium cucumerinum and Aspergillus flavus
(Chludil and Maier 2005). Helianthoside, previously isolated from Heliaster helianthus (Vázquez et al. 1993) was obtained from the ethanolic extract of the body
walls of A. capensis (Díaz de Vivar 2002).
Sulfated polyhydroxysteroids were also extracted from sea stars. Roccatagliata
et al. (1995) reported a novel sulfated polyhydroxysteroid from L. ludwigi scotti
(collected at SMG) together with two other known compounds previously isolated
from Myxoderma platyacanthum (Finamore et al. 1991) and Luidia maculata
(Minale et al. 1984) (Fig. 11.5c).
The first study on sterols from sea stars of the coast of Argentina was by Seldes
and Gros (1985) on C. lurida, and later, a mixture of sterols was obtained from
L. ludwigi scotti by Roccatagliata et al. (1996b). These studies show that
24-methyl-D
7 -sterols account for *40 % of the sterol mixture in both sea stars,
followed by choles-7-en-3b-ol (more than 20 %).
Glycosphingolipids consist of a sphingoid or a ceramide linked at C-1 by a
b-glycosidic bond to a hydrophilic carbohydrate moiety. Glycosylceramides are
the simplest glycosphingolipids and consist of a mono- or a disaccharide chain
linked to the ceramide (http://www.chem.qmul.ac.uk/iupac/misc/glylp.html).
Glucosylceramides (monoglycosylceramides) have been isolated from C. lurida
(Maier et al. 1998), A. capensis (Díaz de Vivar 2002; Díaz de Vivar et al. 2002)
and A. minuta (Chludil et al. 2003a) (Fig. 11.6b). Two new glucosylceramides
were obtained from C. lurida (compounds 3 and 4), together with a mixture of
related cerebrosides obtained as molecular species and Ophidiacerebrosides C and
b Fig. 11.5 a Cosmasterosides a, b, c and d, and Anasterosides a and b. b Sulfated glycosides
from Cosmasterias lurida and Anasterias minuta. c New polyhydroxysteroid from Luidia ludwigi
scotti. d Patagonicoside A and its desulfated analogue; e Novel sulfated polyhydroxysteroid from
Ophioplocus januarii
384
M. I. Brogger et al.
sea star L. ludwigi scotti (Roccatagliata 1996). Versicoside A, an asterosaponin
from Asterias amurensis versicolor (Itakura et al. 1983), was also purified with
Anasterosides A and B from A. minuta (Maier et al. 2002).
Polyhydroxysteroids are also extracted from echinoderms. These compounds
show a polyhydroxylated steroidal aglycone and one or two monosaccharide
moieties with variability in the hydroxylation pattern, the side chain functionalization, the localization of the glycosidic link and the presence of the sulfate
moiety. Two novel steroidal xyloside sulfates (Luridosides A and B) and the
known Pycnopodioside C, previously isolated from Pycnopodia helianthoides
(Bruno et al. 1989), were isolated from the sea star C. lurida (Maier et al. 1993).
Anasterias minuta provided two new sulfated polyhydroxylated steroidal xylosides: Minutosides A and B, together with the known Pycnopodioside B, previously isolated from P. helianthoides (Bruno et al. 1989). Minutoside B is the first
example of a polyhydroxylated steroidal xyloside containing an amide function in
the aglycone side chain (Fig. 11.5b). The three xylosides from A. minuta exhibited
antifungal activity against Cladosporium cucumerinum and Aspergillus flavus
(Chludil and Maier 2005). Helianthoside, previously isolated from Heliaster helianthus (Vázquez et al. 1993) was obtained from the ethanolic extract of the body
walls of A. capensis (Díaz de Vivar 2002).
Sulfated polyhydroxysteroids were also extracted from sea stars. Roccatagliata
et al. (1995) reported a novel sulfated polyhydroxysteroid from L. ludwigi scotti
(collected at SMG) together with two other known compounds previously isolated
from Myxoderma platyacanthum (Finamore et al. 1991) and Luidia maculata
(Minale et al. 1984) (Fig. 11.5c).
The first study on sterols from sea stars of the coast of Argentina was by Seldes
and Gros (1985) on C. lurida, and later, a mixture of sterols was obtained from
L. ludwigi scotti by Roccatagliata et al. (1996b). These studies show that
24-methyl-D
7 -sterols account for *40 % of the sterol mixture in both sea stars,
followed by choles-7-en-3b-ol (more than 20 %).
Glycosphingolipids consist of a sphingoid or a ceramide linked at C-1 by a
b-glycosidic bond to a hydrophilic carbohydrate moiety. Glycosylceramides are
the simplest glycosphingolipids and consist of a mono- or a disaccharide chain
linked to the ceramide (http://www.chem.qmul.ac.uk/iupac/misc/glylp.html).
Glucosylceramides (monoglycosylceramides) have been isolated from C. lurida
(Maier et al. 1998), A. capensis (Díaz de Vivar 2002; Díaz de Vivar et al. 2002)
and A. minuta (Chludil et al. 2003a) (Fig. 11.6b). Two new glucosylceramides
were obtained from C. lurida (compounds 3 and 4), together with a mixture of
related cerebrosides obtained as molecular species and Ophidiacerebrosides C and
b Fig. 11.5 a Cosmasterosides a, b, c and d, and Anasterosides a and b. b Sulfated glycosides
from Cosmasterias lurida and Anasterias minuta. c New polyhydroxysteroid from Luidia ludwigi
scotti. d Patagonicoside A and its desulfated analogue; e Novel sulfated polyhydroxysteroid from
Ophioplocus januarii
384
M. I. Brogger et al.