Isolation and structure identification of new alkaloids from the sponge Rhabdastrella rowi

Chemical investigation on marine sponge Rhabdastrella rowi collected from Bali, Indonesia has been performed. This study was aimed to isolate and to identify structures of the sponge secondary metabolites as well as to test their cytotoxicity activity on mouse lymphoma cell line L5178Y.Isolation procedure was performed by using different chromatography techniques. NMR spectroscopy and mass spectrometry methods were used to identify the compounds chemical structures. Cytotoxicity of the isolates was tested on mouse lymphoma cell line L5178Y by using the microculture tetrazolium (MTT) assay.This study yielded two new alkaloids, quinolin-4-ol (1) and quninazolin-4-amine (2) which were found as minor constituents of Rhabdastrella rowi. Both compounds were observed as inactive against mouse lymphoma cell line L5178Y.Key words: Rhabdastrella rowi, sponge, alkaloid

Protein kinase inhibitors from Indonesian Sponge Axynissa sp.

A research about inhibitory activity on various cancer related protein kinases of several marine sponges collected in Indonesia was performed. This study aims were to isolate and to identify structures of biologically active sponge metabolites.A combination of a chemically-and biologically driven approach for drug discovery was employed. Sponge extracts were tested by protein kinase inhibitory assay by in vitro method in parallel to the usage of TLC, and HPLC coupled to UV spectrophotometry and mass spectrometry to isolate the chemically most interesting substances. Structure identification of active compounds was performed by using NMR spectroscopy and massspectrometry methods.This study showed that only Axynissa sp. fractions were found active in protein kinase inhibitory assay. Two bisabolene type sesquiterpenoids, (+)- curcuphenol (1) and (+)-curcudiol (2) were identified as active compounds from the sponge. Compound 1 showed SRC protein kinase inhibition with an IC50value of 7.8 μg/mL while 2 inhibited FAK with an IC50 value of 9.2 μg/mL.Key words: protein kinase inhibitor, Axynissa sp

Palatability and chemical defenses of sponges from the western Antarctic Peninsula

The present study surveyed the palatability of all sponge species that could be collected in sufficient quantities in a shallow-water area along the western Antarctic Peninsula. Of 27 species assayed, 78% had outermost tissues that were significantly unpalatable to the sympatric, omnivorous sea star Odontaster validus. Of those species with unpalatable outer tissues, 62% had inner tissues that were also unpalatable to the sea stars. Sea stars have often been considered as the primary predators of sponges in other regions of Antarctica, and their extra-oral mode of feeding threatens only the outermost sponge tissues. The observation that many of the sponges allocate defenses to inner tissues suggests the possibility that biting predators such as mesograzers, which could access inner sponge layers, may also be important in communities along the Antarctic Peninsula. In feeding bioassays with extracts from 12 of the unpalatable species in artificial foods, either lipophilic or hydrophilic extracts were deterrent in each species. These data indicate an overall level of chemical defenses in these Antarctic sponges that is comparable to, and slightly greater than, that found in a previous survey of tropical species

Chemical investigation on Indonesian marine sponge Mycale phyllophila

Chemical investigation on marine sponge Mycale phyllophila collected from Bali, Indonesia has been performed. This study was aimed to isolate and to identify structures of the sponge secondary metabolites as well as to test their cytotoxic activity on mouse lymphoma cell line L5178Y.The sponge extract was fractionated by liquid-liquid partition followed with a vacuum liquid chromatography method. Structure elucidation was performed on the basis of extensive spectroscopic analysis involving one and two dimensional NMR spectroscopy as well as mass spectrometry. Cytotoxicity was tested on mouse lymphoma cell line L5178Y by using the microculture tetrazolium (MTT) assay. This study found a mixture of 5-pentadecyl-1H-pyrrole-2-carbaldehyde and (6’E)-5-(6’pentadecenyl)-1H-pyrrole-2-carbaldehyde as major constituents of the sponge extract. Those compounds were expected to be the active constituent to show growth inhibition of mouse lymphoma cell line (L5178Y) in vitro.Key words : Mycale phyllophila, cytotoxic agent, NMR spectroscopy

The Magnitude of Global Marine Species Diversity

Background: The question of how many marine species exist is important because it provides a metric for how much we do and do not know about life in the oceans. We have compiled the first register of the marine species of the world and used this baseline to estimate how many more species, partitioned among all major eukaryotic groups, may be discovered. Results: There are ∼226,000 eukaryotic marine species described. More species were described in the past decade (∼20,000) than in any previous one. The number of authors describing new species has been increasing at a faster rate than the number of new species described in the past six decades. We report that there are ∼170,000 synonyms, that 58,000–72,000 species are collected but not yet described, and that 482,000–741,000 more species have yet to be sampled. Molecular methods may add tens of thousands of cryptic species. Thus, there may be 0.7–1.0 million marine species. Past rates of description of new species indicate there may be 0.5 ± 0.2 million marine species. On average 37% (median 31%) of species in over 100 recent field studies around the world might be new to science. Conclusions: Currently, between one-third and two-thirds of marine species may be undescribed, and previous estimates of there being well over one million marine species appear highly unlikely. More species than ever before are being described annually by an increasing number of authors. If the current trend continues, most species will be discovered this century

On a hexactinellid sponge aggregation at the Great Meteor seamount (North-east Atlantic)

Hexactinellids or glass sponges constitute a predominantly deep-sea sponge group typically occurring at bathyal and abyssal depths. Some species form dense populations along the European and African continental slope but the distribution and extent of these populations remains ill known and the driving factors behind their occurrence poorly understood. Here we report an aggregation of the hexactinellid sponge Poliopogon amadou Thomson, 1878 at ~2700 m depth on the Great Meteor seamount, a large seamount located southern of the Azores archipelago. A description of the species, along with scanning electron microscopy of its spicules, is provided

Shallow water sponges of Jamaica

An annotated comprehensive list is provided of all shallow-water sponges (down to 60 m) recently collected and previously recorded from Jamaica. Five new species are described, Plakina jamaicensis, Melophlus ruber, Agelas repens, Stylissa caribica and Hyrtios tubulatus, two of which belong to genera not recorded before from the Western Atlantic (viz. Melophlus and Stylissa). The number of species recorded from shallow waters (reefs, mangroves and lagoons) now amounts to 157 species, several of which, however, are still of uncertain status

<i>Flagellia</i>, a new subgenus of <i>Haliclona</i> (Porifera, Haplosclerida)

Haplosclerid sponges possessing a unique asymmetric flagelliform type of sigmoid microsclere have been reported from all global oceans. This peculiar spicule, characterized by a circular or elliptical shape, with a longer and sharper curved ending at one side and a shorter and more gradually curved ending at the opposing side, is proposed to be termed ‘flagellosigma’. These sponges invariably also possess smaller normal sigmas while their skeletal structure of oxea megascleres is markedly confused. They are assigned to the large genus Haliclona Grant, 1841 (family Chalinidae) in a new subgenus, Haliclona (Flagellia) subgen. nov. The species belonging to the new subgenus are reviewed and four species new to science are described, Haliclona (Flagellia) indonesiae subgen. et sp. nov., H. (F.) amirantensis subgen. et sp. nov., H. (F.) hiberniae subgen. et sp. nov. and H. (F.) hajdui subgen. et sp. nov. One species, H. (F.) hentscheli nom. nov., is given a new name on account of secondary homonymy caused by its transfer to the genus Haliclona. One species remains unnamed because of paucity of material. Already known species, reassigned to the new subgenus are H. (F.) hamata subgen. et comb. nov., H. (F.) flagellifera subgen. et comb. nov., H. (F.) porosa subgen. et comb. nov., H. (F.) edaphus subgen. et comb. nov. and H. (F.) anataria subgen. et comb. nov. Additional species are likely hiding among many erroneous records of ‘Gellius flagellifer’ from wide ranging parts of the global oceans.</p