The natural products chemistry of West Indian gorgonian octocorals

Abstract

Plexauddae flourish as they do nowhere in the world. Gorgonian corals (order Gorgonacea, phylum Cnidaria) are 4571 4572 A.D. RODRIGUEZ conspicuous members of most tropical and subtropical marine habitats, being the most abundant octocorals found in the West Indies. With over 195 species documented from these two major families, gorgonian octocorals represent an estimated 38% of the known fauna, l Studies of the natural products chemistry of this interesting group of marine invertebrates began in the late 1950's. Since these early investigations, numerous studies of the chemistry of gorgonian corals have been published and summarized. 2-9 This Report documents the exciting chemistry that has been generated through the investigation of gorgonian octocorals from the West Indian region.It includes only research published in refereed journals up to December, 1994. A short communication in Science by Burkholder and Burkholder in 1958, highlighting the occurrence of antibiotic substances in gorgonian corals from Puerto Rico, was used as the starting point for the present review, to This Report is not intended to be comprehensive but instead concentrates on novel marine natural products with interesting biological and pharmaceutical properties. With the exception of several unusual sterols having interesting functionalities, marine sterols, carotenoids, fatty acids, and biopolymers isolated have not been included, since they have been reviewed by specialists, l 1-15 Studies of the chemical ecology aiming at the elucidation of the defensive roles of secondary metabolites from West Indian gorgonians and the value of secondary metabolite composition as a chemotaxonomic tool are discussed. The cited articles were retrieved from computer literature searches by use of Chemical Abstracts (CA Selects), MarinLit, STN International and also NAPRALERT. Terms such as West Indian, Caribbean, gorgonian, sea whip, octocoral, and phylla names were used. The primary focus will be the structural chemistry and biological activities of the metabolites produced by a relatively small group of gorgonians found within a limited geographic area. Wherever possible, every effort was made to record the biological and pharmacological properties of new metabolites. Since marine natural products in general are often the targets of synthetic chemists, we include synthetic work, where available, on novel compounds isolated from these animals.We hope to illustrate the diversity of compounds produced by West Indian gorgonians, while highlighting their specialized ability to biosynthesize secondary metabolites with promising pharmacological activity. 16-19 NATURAL PRODUCTS CHEMISTRYGorgonian metabolites possess novel structures that are largely unknown from terrestrial sources. These animals are now recognized to produce acetogenins, sesquiterpenoids, diterpenoids, prostanoids, and, in some cases, highly functionalized steroids. 7 The chemistry of West Indian gorgonian octocorals will be presented taxonomically according to genus and species (in alphabetic...

The oxidation profile at C-18 of furanocembranolides may provide a taxonomical marker for several genera of octocorals

“…Octocorals of the genera Pseudopterogorgia, Alcyonium, Gersemia, Lophogorgia, Leptogorgia, and Sinularia have the ability to biosynthesize furanocembranolides, 1 highly oxygenated diterpenoids based on the 14-membered carbocyclic cembrane skeleton into which a substituted furan ring and a y-lactone subunit have become embedded. Studies to date indicate that certain members of the family exhibit potent neurotoxicity, 2 in addition to antiinflammatory, 3 antifeedant activity, 4 and other biological properties.…”

Metabolitos secundarios, letalidad y actividad antimicrobiana de los extractos de tres corales y tres moluscos marinos de Sucre, Venezuela

“…Aunque no se ha informado la presencia de alcaloides en octocorales de los géneros Muricea y Eunicea, la biosíntesis de este tipo de compuestos ha sido comprobada en otros organismos marinos, tal es el caso del alcaloide aceropterina aislado del gorgonio caribeño Pseudopterogorgia acerosa y una variedad de alcaloides bioactivos en moluscos bivalvos, esponjas y tunicados (Rodríguez & Soto 1996, Kuramato et al 2004. La detección de triterpenos y sesquiterpenlactonas en los extractos crudos de los octocorales, se correlaciona con la abundancia de este grupo de terpenoides en octocorales pertenecientes a las indias Occidentales (Coll 1992, Rodríguez 1995, en los que destacan diterpenos y sequiterpenlactonas con características estructurales únicas y actividades biológicas significativas, aislados de los géneros Eunicea y Pseudopterogorgia (Rodríguez et al 1998, Rodríguez & Ramírez 2001, Wei et al 2004, Gazón et al 2005. En lo referente a la biosíntesis de terpenos en moluscos, se han aislado diterpenos diacilglicéridos con importante actividad biológica en Austrodoris kerguelencis (Davies-Coleman & Faulkner 1991), posiblemente utilizados por este organismo como mecanismo de defensa.…”

“…Octocorales de los géneros Eunicea, Muricea y Pseudopterogorgia han sido identificados dentro de la fauna invertebrada de las costas venezolanas (González-Brito 1972, Ruiz & Rada 2006, los cuales son miembros importantes dentro de la fauna de las indias Occidentales como fuente de metabolitos secundarios bioactivos (Rodríguez 1995, D'Armas 2002. Por su parte, los moluscos Phyllonotus pomum, Chicoreus brevifrons y Pteria Colymbus se consideran especies importantes desde el punto de vista económico y en el campo de la acuicultura, ya que son especies prolíficas, comestibles y relativamente abundantes (itriago 1977(itriago , Már-quez 1996, lo cual representa una interesante opción en el campo de los productos naturales marinos.…”

Proteomic identification, cDNA cloning and enzymatic activity of glutathione S-transferases from the generalist marine gastropod, Cyphoma gibbosum

“…The high concentration of allelochemicals in gorgonian corals [27,[37][38][39][40], coupled with the findings that digestive glands of C. gibbosum contain high levels of GST activity [9], prompted an investigation to identify and biochemically characterize those GST enzymes possibly responsible for detoxifying gorgonian allelochemicals.…”