Leon S. Ciereszko

Chemistry of coelenterates—VI. Occurrence of gorgosterol, A C30 sterol, in coelenterates and their zooxanthellae

1. 1. The sterols of a number of coelenterates and of their zooxanthellae have been examined by mass spectrometry. The sterols, with C27, C28, C29 and C30 skeletons, occur as complex mixtures. 2. 2. The occurrence of the “gorgosterol” of Bergmann in coelenterates has been confirmed; its molecular weight has been determined by mass spectrometry to be 426, corresponding to C30H50O. 3. 3. The occurrence of gorgosterol in coelenterates is associated with the occurrence of symbiotic zooxanthellae. 4. 4. Zooxanthellae from Anthopleura elegantissima, a sea anemone, and from Tridacna gigas, the giant clam, do not contain gorgosterol. 5. 5. Unfer anaerobic conditions gorgosterol is reduced in the zooxanthellae to a C30H52O compound, “dihydrogorgosterol”.

Chemistry of coelenterates. I. Occurrence of terpenoid compounds in gorgonians.

As part of a study of the comparative biochemistry of marine invertebrates, we have examined a number of gorgonians (class Anthozoa; subclass Alcyonaria; order Gorgonacea) for the occurrence of nonlipid organic compounds. From certain species we have obtained crystalline as well as liquid substances that seem to be terpenoid compounds. These substances appear to account for the antibiotic activity of gorgonian extracts,l for part of the odor of the animals, and for the irritation of skin and eyes caused by handling gorgonians. Yields of the crystalline compounds ranged from 0.005 to 1.5 per cent of the dry weight of gorgonian cortex. The infrared spectra of the solid compounds show strong absorption in the carbonyl region, and the compounds appear to be lactones. The nonlipid oils obtained from the animals are unsaturated hydrocarbons with an admixture of ketonic material.

Marine natural products. Xenicin: a diterpenoid possessing a nine-membered ring from the soft coral, Xenia elongata.

Der neue Naturstoff (I) fand sich erstaunlicherweise nur in Bestanden, die vor Heron Island (Australien) gesammelt wurden, nicht dagegen inExemplaren von der Picnic Bay, Magnetic Island (Australien) oder von den Fidschiinseln.

Vanadium content of some tunicates

Abstract 1. 1. Twenty-nine species of tunicates were examined for vanadium. 2. 2. High concentrations of vanadium were observed only in ascidians of the order Phlebobranchia. 3. 3. Centrifuged blood cells of Ascidia nigra (Savigny) were found to contain 1.45 per cent vanadium. 4. 4. Eggs of Phallusia mamillata Cuvier yielded 0·017 per cent vanadium, dry weight. The ash contained 0·19 per cent vanadium. 5. 5. No vanadium was detected in the four species of salps examined.

Partial characterization of the gonadal hydration principle in the pituitaries of carp (Cyprinus carpio)

Abstract The fraction from carp pituitaries that stimulates seminal plasma elaboration was extracted by various solvents and was partially purified by gel filtration and fractional precipitation. The failure of both formic and trichloroacetic acids to dissociate and active, low molecular weight substance and the relative instability of the active principle in trichloroacetic acid suggest that it does not resemble oxytocin, vasopressin, or arginine vasotocin. The carp fraction is believed to be a gonadotropin since its molecular weight, water solubility, and heat resistance properties are more like those of the mammalian gonadotropin than any other pituitary hormone. Since none of the injected mammalian hormones produced responses in the fish gonadal hydration assay of similar magnitude to carp pituitary extract injections, the carp gonadotropin is not expected to be chemically identical to its mammalian counterpart.

CHEMISTRY OF COELENTERATES. II. OCCURRENCE OF TAUROBETAINE AND CREATINE IN GORGONIANS

taurobetaine, (CH&NCH~CH~SOS-, from Briareum asbestinum (Pallas) in amounts exceeding 0.3 per cent of dry animal. Identity of the substance was established by degradation to trimethylamine and ethylene sulfonic acid, and by comparison of its infrared absorption spectrum with that of synthetic taurobetaine. Examination of extracts of gorgonians by paper chromatography has shown creatine to be present in Plexaura flexuosa Lamouroux, Y. homomalla Esper, P. flavida (Lamarck) , Plexaurella nutans Duchassaing and Michelotti, Plexaurella dichotoma (Esper), Pterogorgia acerosa (Pallas) , Pterogorgia americana (Gmelin) , Rlaipidogorgia jfabellum (L.), and Ihnicea mammosa Lamouroux. Three species, Pterogorgia acerosa, Pterogorgia americana, and Rhipidogorgia jlabellum appeared to contain traces of glycocyamine, a precursor of creatine. No other guanidine bases were detected. +

Toxic effects of cembranolides derived from octocorals on the rotifer Brachionus plicatilis Müller and the amphipod Parhyale hawaiensis (Dana)

Abstract The diterpenoids eunicin, eupalmerin acetate, and crassin acetate derived from octocorals were found to be toxic to the rotifer Brachionus plicatilis Muller and the amphipod Parhyale hawaiensis (Dana) at estimated concentrations ranging from 1 ppm to 100 ppm. Exposure of animals to a concentration ⩾ 1 ppm resulted in either loss of swimming activity or mortality at 48 h. No ciliary loss was evident in the rotifer as had been reported in ciliated larvae of the nudibranch Phestilla sibogae Bergh. The cembranolides may serve as chemical defenses against predation and in the competition for space amongst the sessile organisms on coral reefs.

Chemistry of coelenterates. Sterol composition of some predator-prey pairs on coral reefs

Abstract 1. 1. Sterol mixtures isolated from a number of coral reef coelenterates and their associated “predators”, crabs, a snail and a polychaete worm, were analyzed by a combination of gas liquid chromatography and mass spectrometry. 2. 2. The C30 sterol gorgosterol characteristic of coral reef coelenterates was used as a “tracer” to detect predation. 3. 3. The sterol composition of the alleged predators reflected that of the coelenterates on which they were found. 4. 4. Two new, C31 sterols, tentatively identified as 4-methyl-gorgostanol (m/e 442) and 4-methylgorgosterol (m/e 440) were found to occur in relatively large amounts in the zooxanthellae isolated from the gorgonian Briareum asbestinum.

The influence of some cembranolides from gorgonian corals on motility of marine flagellates

Abstract Crassin acetate, eunicin and eupalmerin acetate, three cembranolides (14-member ring diterpenoid lactones) derived from Caribbean gorgonians, were tested for their effect on a variety of marine flagellates. Included were three isolates of the genus Symbiodinium whose nonmotile forms occur as symbiotic zooxanthellae in coral reef organisms. Eunicin at a concentration of 5 ppm in seawater immobilized most of the flagellates tested. At 10 ppm eucinin immobilized in 10 min three organisms not affected within 24 h at 5 ppm. Crassin acetate and eupalmerin acetate were found active in limited testing.

Evidence for a collagen-like protein within spicules of coelenterates

Abstract 1. Calciferous spicules were obtained fromBriareum asbestinum, a gorgonian or “soft” coral. 2. The spicules were washed extensively and treated with potassium hydroxide to remove the exterior sheath and any proteins on the outside. 3. After solubilization of the calcium carbonate with acid, an insoluble material remained. 4. Peptides with molecular weights between 1600 and 5000 were isolated from this core material. 5. These peptides had amino acid compositions characteristic of the collage like proteins.