Studies of Australian soft corals. XXXIII. New cembranoid diterpenes from a Lobophytum species

1983 ◽  
Vol 36 (11) ◽  
pp. 2289 ◽  
Author(s):  
BF Bowden ◽  
JC Coll ◽  
DM Tapiolas
Keyword(s):  
Soft Coral ◽  
Minor Component ◽  
Major Metabolite ◽  
Soft Corals ◽  
Aerial Oxidation ◽  
A Minor ◽  
Sole Product

The isolation of two new cembranoid diterpenes, (14S,1E,3E,7E)-14-acetoxy-11,12-epoxycembra-1,3,7-triene and the corresponding 14-alcohol, is reported from the soft coral Lobophytum sp. A minor component in the extract (3S,4S,1lS,12S,1E,7E)-3,4:11,12-bisepoxycembra-1,7-diene was identified but may be artefactual as it is the sole product of the aerial oxidation of the major metabolite(11S,12S,1 E,3E,7E)-11,12-epoxycembra-1,3,7-triene. Further examples of stereospecific epoxidationsare reported.

Studies of Australian Soft Corals. XLIV. New Diterpenes From Sinularia polydactyla (Coelenterata, Anthozoa, Octocorallia)

1989 ◽  
Vol 42 (5) ◽  
pp. 757 ◽  
Author(s):  
BF Bowden ◽  
JC Coll ◽  
AD Wright
Keyword(s):  
Natural Products ◽  
Soft Coral ◽  
Soft Corals ◽  
Spectral Comparison ◽  
A Minor

The soft coral Sinularia polydactyla has yielded six highly functionalized diterpenes. The known diterpenes pukalide (2) and 1-epithunbergol (3) were readily identified by spectral comparison with authentic samples. The new natural products 13 α-acetoxy-11β, 12β-epoxypukalide (4),13 α-acetoxypukalide (5) and its allylically rearranged isomer (6) were identified on the basis of 2D-n.m.r. experiments at 300 MHz and by spectral comparison with the known compounds pukalide (21, lophotoxin (8) and epoxypukalide (9). A minor, relatively unstable metabolite (7) is tentatively identified as a 3,4:5,6-bisepoxy derivative of (6). The biological implications of these findings are discussed.

Studies of Australian soft corals. IV. A novel bicyclic diterpene from Lobophytum hedleyi

1978 ◽  
Vol 31 (1) ◽  
pp. 163 ◽  
Author(s):  
BF Bowden ◽  
JC Coll ◽  
N Liyanage ◽  
SJ Mitchell ◽  
GJ Stokie ◽  
...  
Keyword(s):  
Minor Component ◽  
Hydroxy Derivative ◽  
Soft Corals ◽  
A Minor ◽  
Final Proof

A new bicyclic diterpene, (3E,5E)-2-methyl-6-[(2'R*,4a'S*,8a'R*)-4a'-methyl-8'-methylene-trans-perhydronaphthalen-2'-yl]hepta-3,5-dien-2-ol (1), is reported as the major terpenoid component from Lobophytum hedleyi. It represents the first non-cembranoid diterpene to be reported from soft corals. A minor component in the coral is tentatively identified as the 7-hydroxy derivative of (1). Evidence for the structure of (1) is mainly spectroscopic but final proof rests on degradation and conversion into a known compound.

Protonation effects on dynamic flux properties of aqueous metal complexes

2009 ◽  
Vol 74 (10) ◽  
pp. 1543-1557 ◽  
Author(s):  
Herman P. Van Leeuwen ◽  
Raewyn M. Town
Keyword(s):  
Complex Formation ◽  
Metal Ion ◽  
Good Description ◽  
Minor Component ◽  
Outer Sphere ◽  
Metal Species ◽  
Central Metal ◽  
Inner Sphere ◽  
A Minor ◽  
Protonated Ligand

The degree of (de)protonation of aqueous metal species has significant consequences for the kinetics of complex formation/dissociation. All protonated forms of both the ligand and the hydrated central metal ion contribute to the rate of complex formation to an extent weighted by the pertaining outer-sphere stabilities. Likewise, the lifetime of the uncomplexed metal is determined by all the various protonated ligand species. Therefore, the interfacial reaction layer thickness, μ, and the ensuing kinetic flux, Jkin, are more involved than in the conventional case. All inner-sphere complexes contribute to the overall rate of dissociation, as weighted by their respective rate constants for dissociation, kd. The presence of inner-sphere deprotonated H2O, or of outer-sphere protonated ligand, generally has a great impact on kd of the inner-sphere complex. Consequently, the overall flux can be dominated by a species that is a minor component of the bulk speciation. The concepts are shown to provide a good description of experimental stripping chronopotentiometric data for several protonated metal–ligand systems.

scholarly journals Species Diversity and Secondary Metabolites of Sarcophyton-Associated Marine Fungi

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3227
Author(s):  
Yuanwei Liu ◽  
Kishneth Palaniveloo ◽  
Siti Aisyah Alias ◽  
Jaya Seelan Sathiya Seelan
Keyword(s):  
Secondary Metabolites ◽  
Soft Coral ◽  
Marine Fungi ◽  
Indole Alkaloids ◽  
Structural Diversity ◽  
Future Research ◽  
Soft Corals ◽  
Diverse Range ◽  
Symbiotic Relationships ◽  
Bioactive Secondary Metabolites

Soft corals are widely distributed across the globe, especially in the Indo-Pacific region, with Sarcophyton being one of the most abundant genera. To date, there have been 50 species of identified Sarcophyton. These soft corals host a diverse range of marine fungi, which produce chemically diverse, bioactive secondary metabolites as part of their symbiotic nature with the soft coral hosts. The most prolific groups of compounds are terpenoids and indole alkaloids. Annually, there are more bio-active compounds being isolated and characterised. Thus, the importance of the metabolite compilation is very much important for future reference. This paper compiles the diversity of Sarcophyton species and metabolites produced by their associated marine fungi, as well as the bioactivity of these identified compounds. A total of 88 metabolites of structural diversity are highlighted, indicating the huge potential these symbiotic relationships hold for future research.

Petrography and provenance of the Marambio Group, Vega Island, Antarctica

1994 ◽  
Vol 6 (4) ◽  
pp. 517-527 ◽  
Author(s):  
Duncan Pirrie
Keyword(s):  
Late Cretaceous ◽  
Sedimentary Rocks ◽  
Clay Mineralogy ◽  
Minor Component ◽  
Source Area ◽  
Low Grade ◽  
Western Margin ◽  
Sediment Input ◽  
A Minor ◽  
Sandstone Petrography

Late Cretaceous sedimentary rocks assigned to the Santa Marta (Herbert Sound Member) and López de Bertodano (Cape Lamb and Sandwich Bluff members) formations of the Marambio Group, crop out on Cape Lamb, Vega Island. Although previous studies have recognized that these sedimentary rocks were derived from the northern Antarctic Peninsula region, the work presented here allows the provenance and palaeogeographical evolution of the region to be described in detail. On the basis of both sandstone petrography and clay mineralogy, the Herbert Sound and Cape Lamb members reflect sediment input from a low relief source area, with sand grade sediment sourced from low grade metasediments, and clay grade sediment ultimately derived from the weathering of an andesitic source area. In contrast, the Sandwich Bluff Member reflects a switch to a predominantly andesitic volcaniclastic source. However, this sediment was largely derived from older volcanic suites due to renewed source area uplift, with only a minor component from coeval volcanism. Regional uplift of both the arc terrane and the western margin of the James Ross Basin was likely during the Maastrichtian.

scholarly journals Species pattern of phosphatidylinositol from lung surfactant and a comparison of the species pattern of phosphatidylinositol and phosphatidylglycerol synthesized de novo in lung microsomal fractions

1988 ◽  
Vol 254 (1) ◽  
pp. 67-71 ◽  
Author(s):  
B Rüstow ◽  
Y Nakagawa ◽  
H Rabe ◽  
K Waku ◽  
D Kunze
Keyword(s):  
Lung Function ◽  
Molecular Species ◽  
De Novo ◽  
Lung Surfactant ◽  
Minor Component ◽  
Main Species ◽  
Surfactant Phospholipids ◽  
Species Pattern ◽  
A Minor

1. Phosphatidylinositol (PI) is a minor component of lung surfactant which may be able to replace the functionally important phosphatidylglycerol (PG) [Beppu, Clements & Goerke (1983) J. Appl. Physiol. 55, 496-502] without disturbing lung function. The dipalmitoyl species is one of the main species for both PI (14.4%) and PG (16.9%). Besides the C16:0--C16:0 species, the C16:0--C18:0, C16:0--C18:1, C16:0--C18:2 and C18:0--C18:1 species showed comparable proportions in the PG and PI fractions. These similarities of the species patterns and the acidic character of both phospholipids could explain why surfactant PG may be replaced by PI. 2. PI and PG were radiolabelled by incubation of microsomal fractions with [14C]glycerol 3-phosphate (Gro3P). For 11 out of 14 molecular species of PI and PG we measured comparable proportions of radioactivity. The radioactivity of these 11 species accounted together for more than 80% of the total. The addition of inositol to the incubation system decreased the incorporation in vitro of Gro3P into PG and CDP-DG (diacylglycerol) of lung microsomes (microsomal fractions), but did not change the distribution of radioactivity among the molecular species of PG. These results supported the idea that both acidic surfactant phospholipids may be synthesized de novo from a common CDP-DG pool in lung microsomes.

scholarly journals Recreational Harvest of Sharks and Rays in Western Australia Is Only a Minor Component of the Total Harvest

2021 ◽  
Vol 13 (11) ◽  
pp. 6215
Author(s):  
Matias Braccini ◽  
Eva Lai ◽  
Karina Ryan ◽  
Stephen Taylor
Keyword(s):  
Western Australia ◽  
Minor Component ◽  
The North ◽  
Commercial Harvest ◽  
Unknown Status ◽  
Reef Sharks ◽  
Conservation Concern ◽  
Taxonomic Groups ◽  
A Minor ◽  
Port Jackson

Sharks and rays are a global conservation concern with an increasing number of species considered at risk of extinction, mostly due to overfishing. Although the recreational harvest of sharks and rays is poorly documented and generally minimal, it can be comparable to the commercial harvest. In this study, we quantified the recreational harvest of sharks and rays in Western Australia, a region with a marine coastline greater than 20,000 km. A total of 33 species/taxonomic groups were identified, with the harvest dominated by dusky and bronze whalers, blacktip reef sharks, gummy sharks, Port Jackson sharks, wobbegongs, and rays and skates. Eighty-five percent of individuals were released with an unknown status (alive or dead). We found a latitudinal gradient of species composition, with tropical and subtropical species of the genus Carcharhinus dominating in the north and temperate species from a range of families dominating in the south. Overall, our findings showed that the recreational harvest was negligible when compared with commercial landings.

scholarly journals Rat liver alcohol dehydrogenase. Purification and properties

1971 ◽  
Vol 125 (4) ◽  
pp. 1039-1047 ◽  
Author(s):  
M J Arslanian ◽  
E Pascoe ◽  
J G Reinhold
Keyword(s):  
Molecular Weight ◽  
Alcohol Dehydrogenase ◽  
Rat Liver ◽  
Gel Filtration ◽  
Rabbit Antiserum ◽  
Minor Component ◽  
Disc Electrophoresis ◽  
Supernatant Fraction ◽  
Liver Alcohol Dehydrogenase ◽  
A Minor

Alcohol dehydrogenase (EC 1.1.1.1) from the rat liver supernatant fraction has been purified 200-fold and partially characterized. The isolation procedure involved ammonium sulphate fractionation, DEAE-Sephadex chromatography and gel filtration. The purified enzyme behaved as a homogeneous preparation as evaluated by cellulose acetate and polyacrylamide-gel disc electrophoresis. Sulphoethyl-Sephadex chromatography and immunoelectrophoresis with rabbit antiserum indicated the presence of a minor component. Rat liver alcohol dehydrogenase appears to contain 4mol of zinc/mol, has an estimated molecular weight of 65000 and consists of two subunits of similar molecular weight. Heavy-metal ions, thiol-blocking reagents, urea at concentrations below 8m, low pH (5.5) and chelating agents deactivate the enzyme but do not dissociate it into subunits. Deactivated enzyme could not be reactivated. The enzyme is strictly specific for NAD+ and has a broad specificity for alcohols, which are bound at a hydrophobic site. Inhibition occurred with the enzyme equilibrated with Zn2+ at concentrations above 0.1mm.

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