Caledonian Marine Research Articles

Current knowledge of New Caledonian marine and freshwater ichthyofauna, SW Pacific Ocean: diversity, exploitation, threats and management actions

Current knowledge of New Caledonian marine and freshwater ichthyofauna, SW Pacific Ocean: diversity, exploitation, threats and management actions

A new freshwater crab of the family Hymenosomatidae MacLeay, 1838 (Crustacea, Decapoda, Brachyura) and an updated review of the hymenosomatid fauna of New Caledonia

A new genus and species, Richerius marqueti gen. et sp. nov., of a crab of the family Hymenosomatidae MacLeay, 1838 are described from the inland waters of New Caledonia based on several specimens collected in two streams at altitudes of 180 m and 500 m, respectively. Richerius marqueti gen. et sp. nov. was compared to the other freshwater species known in New Caledonia, Odiomaris pilosus (A. Milne-Edwards, 1873), and to species of Amarinus Lucas, 1980, a genus comprising many freshwater species in New Zealand, Australia, Indonesia, the Philippines, and Papua New Guinea, but never recorded in New Caledonia. The barcode fragment of the COI mitochondrial gene was sequenced for seven specimens of R. marqueti gen. et sp. nov., and all sequences were deposited in GenBank. A brief and updated review of the New Caledonian marine and freshwater hymenosmatid fauna is provided.

Nepheliosyne B, a new polyacetylenic acid from the new caledonian marine sponge Niphates sp.

A new C47 polyoxygenated acetylenic acid, nepheliosyne B (2), along with the previously described nepheliosyne A (1), have been isolated from the New Caledonian marine sponge Niphates sp. Their structures have been elucidated on the basis of extensive spectroscopic analyses. These metabolites exhibited a moderate cytotoxicity against K562, U266, SKM1, and Kasumi cancer cell lines.

Total Synthesis of (−)‐Reidispongiolide A, an Actin‐Targeting Macrolide Isolated from the Marine Sponge Reidispongia coerulea

A stereocontrolled total synthesis of the microfilament-destabilizing cytotoxic macrolide (-)-reidispongiolide A, isolated from the New Caledonian marine sponge Reidispongia coerulea, is described. This synthesis utilizes a convergent aldol-based strategy to construct the 26-membered macrolactone, followed by the late-stage coupling of a derived aldehyde with an N-vinylformamide-containing ketone subunit to install the full side chain. Two alternative routes were examined for the introduction of the 2E,4E-dienoate region, and a complex Mukaiyama aldol coupling was used to connect the northern and southern hemispheres to install the C13 stereocenter. This constitutes the first chemical synthesis of any member of the reidispongiolide/sphinxolide family of marine macrolides and unequivocally establishes the relative and absolute configuration.

On the First Polyarsenic Organic Compound from Nature: Arsenicin A from the New Caledonian Marine Sponge Echinochalina bargibanti

Reported here is the first polyarsenic compound ever found in nature. Denominated arsenicin A, it was isolated along a bioassay-guided fractionation of the organic extract of the poecilosclerid sponge Echinochalina bargibanti collected from the north-eastern coast of New Caledonia. In defining an adamantine-type polyarsenic structure for this compound, deceptively simple NMR spectra were complemented by extensive mass spectral analysis. However, it was only the synthesis of a model compound that provided the basis to discriminate structure 4 from other spectrally compatible structures for arsenicin A; to this end, a comparative ab initio simulation of IR spectra for the natural and the synthetic compounds was decisive. Arsenicin A is endowed with potent bactericidal and fungicidal activities on human pathogenic strains. All this may revive pharmacological interest in arsenic compounds while prompting us to rethink the arsenic cycle in nature.

Natural‐Product Diversity of the New Caledonian Marine Ecosystem Compared to Other Ecosystems: A Pharmacologically Oriented View

In comparison with other ecosystems, biodiversity and natural-product diversity of the New Caledonian marine ecosystem, comprising lagoons, barrier reefs, and deep waters in seamount regions, are described here phylogenetically with the aid of molecular drawings and tabulation of data. Admittedly, since the inception of these studies in 1977, the comparison is biased by selection of New Caledonian organisms on the basis of positive pharmacologically oriented bioassays. However, we show that these and other distortions must be accepted to draw any comparison on a regional basis, which, nonetheless, turn out to be useful for the progress of knowledge, particularly in directing future explorations of biodiversity in the search for new pharmacologically active metabolites.

A New Cytotoxic Tetralone Derivative from Humicola grisea, a Filamentous Fungus from Wood in the Southeastern Lagoon of New Caledonia

AbstractFor Abstract see ChemInform Abstract in Full Text.

A new cytotoxic tetralone derivative from Humicola grisea, a filamentous fungus from wood in the southeastern lagoon of New Caledonia

Humicolone, a new phenolic tetralone in acetal form, was isolated, together with a known phenolic tetralone, from cultures of Humicola grisea Traaen, a hyphomycete taken from drifting wood in the southeastern lagoon of New Caledonia. Humicolone, determined from MTPA esters to have absolute configuration 1′ R,3 S,4 S, showed cytotoxicity on KB cell lines, with IC 50 values between 1 and 5 ppm. Another unidentified filamentous fungus, also from drifting wood in a nearby New Caledonian marine area, gave phosphatidyl cholines and, unusually for fungi, a bisabolane sesquiterpene.

New cytotoxic isomalabaricane-type sesterterpenes from the New Caledonian marine sponge Rhabdastrella globostellata

Four new cytotoxic isomalabaricane sesterterpenes, aurorals 1– 4, have been isolated from the New Caledonian marine sponge Rhabdastrella globostellata. Their structures were established by spectroscopic data including 1D and 2D techniques. These compounds were found to exhibit cytotoxic activity on KB cells.

Methanol adduct of puupehenone, a biologically active derivative from the marine sponge Hyrtios species.

A methanol adduct of puupehenone (1), 15alpha-methoxypuupehenol (2), an artifact resulting from the action of MeOH on puupehenone, was isolated during purification of the CH(2)Cl(2) extract of the New Caledonian marine sponge Hyrtios sp., as the major constituent. Its chemical structure was elucidated by 2D NMR experiments. Compound 2 displayed similar antimicrobial and antifungal activity as puupehenone and a lower cytotoxic activity toward KB cells with ED(50) values of 6 and 0.5 microg/mL, respectively. Compound 2 was slightly more active against three strains of Plasmodium falciparum than puupehenone.

Petrosaspongiolides M-R: new potent and selective phospholipase A2 inhibitors from the New Caledonian marine sponge Petrosaspongia nigra.

Five new bioactive sesterterpenes (1-5) have been isolated from the New Caledonian marine sponge Petrosaspongia nigra Bergquist and named petrosaspongiolides M-R. Their chemical structures were determined from 1D and 2D NMR studies and MS data. All compounds inhibited different preparations of phospholipase A2 (PLA2) by irreversibly blocking these enzymes (particularly human synovial and bee venom, see Table 3), with IC50 values in the micromolar range. Interestingly, these compounds displayed a much lower activity (or no activity at all) toward porcine pancreas and Naja naja venom PLA2 enzymes. The most potent compound, 1 (IC50 1.6 and 0.6 microM for human synovial and bee venom PLA2 enzymes, respectively), was slightly more active than manoalide (6) (IC50 3.9 and 7.5 microM) under our experimental conditions. Compound 3 is more selective, inhibiting human synovial PLA2 to a greater extent than bee venom PLA2.

New cytotoxic sesterterpenes from the New Caledonian marine sponge Petrosaspongia nigra (Bergquist)

Abstract Along with two known cheilanthane sesterterpene lactones, 1 and 2, eight new related sesterterpenes (3–10) and two new nor-sesterterpenes (11 and 12) have been isolated from the New Caledonian marine sponge Petrosaspongia nigra Bergquist 1995 (new genus, new species). Their structures were determined from 1D and 2D NMR studies and mass spectral data. They exhibited cytoxicity against the NSCLC-N6 human bronchopulmunary non-small-cell-lung carcinoma cell lines.

Pyraxinine, a Novel Nitrogenous Compound from the Marine Sponge Cymbastela cantharella

Four minor polar nitrogen compounds have been isolated from the New Caledonian marine sponge, Cymbastela cantharella. Three are the known products allantoin, homarine, and trigonelline and the fourth is novel. The structure of the new compound, pyraxinine (1), was shown to be 3-pyridylguanidine by spectroscopic analysis and synthesis.

Dipuupehedione, a cytotoxic new red dimer from a new caledonian marine sponge hyrtios sp

Dipuupehedione, a cytotoxic new red dimer of puupehenone was isolated from a New Caledonian marine sponge Hyrtios sp. and its structure established through spectral studies, including extensive 2 D NMR spectroscopy. Dipuupehedione is active on KB cells (IC 50 = 3 μg/ml).

Further brominated bis- and tris-indole alkaloids from the deep-water New Caledonian marine sponge Orina Sp.

Two tris-indole alkaloids, (+/-) gelliusines A and B [1], have been isolated for the first time from a marine source, the New Caledonian sponge, Orina sp. (or Gellius sp.), along with five further indole constituents [2-6]. Compound 6 has been identified as 2,2-bis-(6'-bromo-3'-indolyl(-ethylamine, previously isolated from the tunicate Didemnum candidum, but the remaining four indoles [2-5] are novel compounds. These showed anti-serotonin activity and a strong affinity for somatostatin and neuropeptide Y receptors in receptor-binding assays.

(±)-Gelliusines A and B, Two Diastereomeric Brominated Tris-indole Alkaloids from a Deep Water New Caledonian Marine Sponge (Gellius or Orina sp.)

Two new diastereomeric brominated tris-indole alkaloids occurring as enantiomeric pairs, (+/-)-gelliusines A [1] and B [2], have been isolated from a deep water New Caledonian sponge (Gellius or Orina sp.), whose crude extract exhibited cytotoxicity against KB cells. Their structures were elucidated by spectroscopic methods including one- and two-dimensional nmr spectroscopy. The major compound, (+/-) gelliusine A [1], which showed very weak cytotoxicity, proved to be active at the serotonin receptor.

Reidispongiolide A and B, two new potent cytotoxic macrolides from the new caledonian sponge Reidispongia coerulea

Two new 26-membered macrolides, reidispongiolide A ( 1) and B ( 2), have been isolated from the New Caledonian marine sponge Redispongia coerulea n.gen.n.sp. Lévi and Lévi and their structures elucidated. They are related to sphinxolides previously isolated from an unknown nudibranch and later from the sponge Neosiphonia superstes. 1 and 2 co-occurr with sphinxolide B ( 4) and D ( 3). These macrolides exhibited potent cytotoxicity against various human carcinoma cells.