132
WERNER BERGMANN
a sterol believed to be /?-sitosterol (95). These contradictory observations suggest either that the sterols of Anthopleura reflect the diet of
the animals, or more likely that one or another of the species has been
misidentified or placed within the wrong family.
A more interesting diversity of sterols is encountered among the
colonial anthozoa belonging to the orders of gorgonias, Madreporaria
(corals), and zoantharia, the colonial sea anemones. Two of the latter
have each given a different sterol. The one is the rather widely distributed 24-methylenecholesterol, obtainable from the animal in a surprisingly uniform state (38, 92). The other, provisionally named palysterol, appears to be a new compound of unknown structure, m.p. 140°,
[a] D —47°; acetate, m.p. 152°, [ a ] D —52° (21). Sterols or sterol mixtures melting higher than the natural sterols now known have been
isolated from gorgonias and corals. One of the former contains a sterol
tentatively called gorgosterol (96), m.p. 184-185°, [a] D —45°; acetate,
m.p. 140° clear at 152°, [a] D —56°; and one of the corals, a sterol of
m.p. 176-177° (96). Such exceptionally high melting points set these
sterols apart from other levorotatory A
5 -sterols and suggest the presence
of a side chain or other structural features not heretofore encountered.
A more systematic study of these sterols should furnish data significant
to the understanding of the biochemical evolution of sterols. It is of interest to note that all major coelenterate sterols which have been observed so far belong to group II, the A
5 -sterols. They are generally accompanied by small amounts of the provitamin D sterols of group I.
No significant quantities of saturated sterols have yet been found,
which are so characteristic of certain sponge families; nor any of the
A
7 -sterols of group III, typical of certain sponges, mollusks, and
echinoderms.
VI. Sterols of Ctenophores to Annelids
With but very few exceptions nothing appears to be known about
the sterols of the many and diverse animals which have been assigned
to the six or more phyla generally placed between the Coelenterata
and Arthropoda. Substantial quantities of cholesterol have been isolated from the parasitic flatworms (Plathelminthes) such as the fish
tapeworm, Botriocephalus hhis (Diphyllobotrium fotum) (100), the
liver fluke, Fasciola hepatica (101), and the cat and beef tapeworms,
Taenia taeniaeformis (102) and T. saginata (103). Cholesterol is also
the principal sterol of Ascaris lumbricoides (104), the eelworm of the
phylum of roundworms (Nemathelminthes). The common earthworm,
Lumbricus terrestris, of the phylum Annelida, has been «shown to contain cholesterol as the principal sterol (6, 105), accompanied by as
WERNER BERGMANN
a sterol believed to be /?-sitosterol (95). These contradictory observations suggest either that the sterols of Anthopleura reflect the diet of
the animals, or more likely that one or another of the species has been
misidentified or placed within the wrong family.
A more interesting diversity of sterols is encountered among the
colonial anthozoa belonging to the orders of gorgonias, Madreporaria
(corals), and zoantharia, the colonial sea anemones. Two of the latter
have each given a different sterol. The one is the rather widely distributed 24-methylenecholesterol, obtainable from the animal in a surprisingly uniform state (38, 92). The other, provisionally named palysterol, appears to be a new compound of unknown structure, m.p. 140°,
[a] D —47°; acetate, m.p. 152°, [ a ] D —52° (21). Sterols or sterol mixtures melting higher than the natural sterols now known have been
isolated from gorgonias and corals. One of the former contains a sterol
tentatively called gorgosterol (96), m.p. 184-185°, [a] D —45°; acetate,
m.p. 140° clear at 152°, [a] D —56°; and one of the corals, a sterol of
m.p. 176-177° (96). Such exceptionally high melting points set these
sterols apart from other levorotatory A
5 -sterols and suggest the presence
of a side chain or other structural features not heretofore encountered.
A more systematic study of these sterols should furnish data significant
to the understanding of the biochemical evolution of sterols. It is of interest to note that all major coelenterate sterols which have been observed so far belong to group II, the A
5 -sterols. They are generally accompanied by small amounts of the provitamin D sterols of group I.
No significant quantities of saturated sterols have yet been found,
which are so characteristic of certain sponge families; nor any of the
A
7 -sterols of group III, typical of certain sponges, mollusks, and
echinoderms.
VI. Sterols of Ctenophores to Annelids
With but very few exceptions nothing appears to be known about
the sterols of the many and diverse animals which have been assigned
to the six or more phyla generally placed between the Coelenterata
and Arthropoda. Substantial quantities of cholesterol have been isolated from the parasitic flatworms (Plathelminthes) such as the fish
tapeworm, Botriocephalus hhis (Diphyllobotrium fotum) (100), the
liver fluke, Fasciola hepatica (101), and the cat and beef tapeworms,
Taenia taeniaeformis (102) and T. saginata (103). Cholesterol is also
the principal sterol of Ascaris lumbricoides (104), the eelworm of the
phylum of roundworms (Nemathelminthes). The common earthworm,
Lumbricus terrestris, of the phylum Annelida, has been «shown to contain cholesterol as the principal sterol (6, 105), accompanied by as