Chemical composition, nutritive value and health benefits of edible clam (Chemnitz) from West Coast of India.

The present study was undertaken with a view to determine the nutraceutical value of the commonly consumed edible clam, (Chemnitz), based on the identification of its organic chemical constituents particularly lipids and carbohydrates. Electrospray ionization tandem mass analysis of the bivalve indicated maltodextrins to be the major carbohydrate constituent. Triacylglycerols (TAGs) (0.

Novel Conopeptides of Largely Unexplored Indo Pacific Conus sp.

Cone snails are predatory creatures using venom as a weapon for prey capture and defense. Since this venom is neurotoxic, the venom gland is considered as an enormous collection of pharmacologically interesting compounds having a broad spectrum of targets. As such, cone snail peptides represent an interesting treasure for drug development.

Discovery of a new subclass of α-conotoxins in the venom of Conus australis.

Cone snails (Conus sp.) are poisonous animals that can be found in all oceans where they developed a venomous strategy to prey or to defend. The venom of these species contains an undeniable source of unique and potent pharmacologically active compounds.

Bioactive cembrane derivatives from the Indian Ocean soft coral, Sinularia kavarattiensis.

Marine organisms and their metabolites represent a unique source of potential pharmaceutical substances. In this study, we examined marine-derived substances for their bioactive properties in a cell-based Chikungunya virus (CHIKV) replicon model and for in vitro anti-inflammatory activity. In the screening of a marine sample library, crude extracts from the Indian soft coral, Sinularia kavarattiensis, showed promising activity against the CHIKV replicon.

Design and synthesis of marine natural product-based 1H-indole-2,3-dione scaffold as a new antifouling/antibacterial agent against fouling bacteria.

Marine organisms such as seaweeds, sponges and corals protect their own surfaces from fouling by their high anesthetic, repellant, and settlement inhibition properties. Within the marine ecosystem, evolution has allowed for the development of certain antifouling properties. Isatin is a biologically active chemical produced by an Alteromonas sp.

Marine and semi-synthetic hydroxysteroids as new scaffolds for pregnane X receptor modulation.

In recent years many sterols with unusual structures and promising biological profiles have been identified from marine sources. Here we report the isolation of a series of 24-alkylated-hydroxysteroids from the soft coral Sinularia kavarattiensis, acting as pregnane X receptor (PXR) modulators. Starting from this scaffold a number of derivatives were prepared and evaluated for their ability to activate the PXR by assessing transactivation and quantifying gene expression.

Evaluation of single and joint effect of metabolites isolated from marine sponges, Fasciospongia cavernosa and Axinella donnani on antimicrobial properties.

The biochemical mechanisms that marine sponges have developed as a chemical defense to protect themselves against micro and subsequent macrobiofouling process might comprise a potential alternative for the preventing attack of biofilm forming bacteria. The present study investigated the antimicrobial activity of a series of major secondary metabolites isolated from the sponges Fasciospongia cavernosa and Axinella donnani against fouling bacteria. Secomanoalide (1), dehydromanoalide (2) and cavernosine (3) have been isolated from F.

Structure-function elucidation of a new α-conotoxin, Lo1a, from Conus longurionis.

α-Conotoxins are peptide toxins found in the venom of marine cone snails and potent antagonists of various subtypes of nicotinic acetylcholine receptors (nAChRs). nAChRs are cholinergic receptors forming ligand-gated ion channels in the plasma membranes of certain neurons and the neuromuscular junction. Because nAChRs have an important role in regulating transmitter release, cell excitability, and neuronal integration, nAChR dysfunctions have been implicated in a variety of severe pathologies such as epilepsy, myasthenic syndromes, schizophrenia, Parkinson disease, and Alzheimer disease.

In vitro and in vivo activities of antibiotic PM181104.

Drug resistance has become a global threat that, if not addressed, may return us to the preantibiotic era. A way to overcome the problem of growing incidence of global antibiotic resistance is to introduce compounds belonging to classes that are new to the clinic. During a screening of the marine microbial extract library for new antibiotics, one of the extracts showed promising antibacterial activity against Gram-positive organisms.

Synthesis of (R)-norbgugaine and its potential as quorum sensing inhibitor against Pseudomonas aeruginosa.

(R)-Bgugaine is a natural pyrrolidine alkaloid from Arisarum vulgare, which shows antifungal and antibacterial activity. In this Letter, we have accomplished the simple synthesis of norbgugaine (demethylated form of natural bgugaine) employing Wittig olefination and cat. hydrogenation as the key steps and its biological studies are reported for the first time.

Chemistry of the nudibranch Aldisa andersoni: structure and biological activity of phorbazole metabolites.

The first chemical study of the Indo-Pacific dorid nudibranch Aldisa andersoni resulted in the isolation of five chlorinated phenyl-pyrrolyloxazoles belonging to the phorbazole series. Two new molecules, 9-chloro-phorbazole D and N1-methyl-phorbazole A, co-occurring with known phorbazoles A, B and D, have been characterized. Phorbazoles were found to be present mainly in the external part of the mollusc.

Identifying the related compounds using electrospray ionization tandem mass spectrometry: bromotyrosine alkaloids from marine sponge Psammaplysilla purpurea.

We have investigated extracts of marine sponge Psammaplysilla purpurea during three collections from Mandapam (Tamil Nadu, India) and Okha (Gujarat, India) and indentified two new bromotyrosine alkaloids, purpurealidin I (7) and J (8) using electrospray ionization tandem mass spectrometry (ESI-MS/MS). This sponge has tremendous chemical diversity of bromotyrosine alkaloids. Here we have used the proteomics approach in identifying related bromotyrosine alkaloids based on the predicated mass fragmentation pattern.

The sponge-associated bacterium Bacillus licheniformis SAB1: a source of antimicrobial compounds.

Several bacterial cultures were isolated from sponge Halichondria sp., collected from the Gujarat coast of the Indo Pacific region. These bacterial cultures were fermented in the laboratory (100 mL) and the culture filtrate was assayed for antibiotic activity against 16 strains of clinical pathogens.

Antimicrobial lipids from the hemolymph of brachyuran crabs.

The potential of marine crabs as a source of biologically active products is largely unexplored. In the present study, antimicrobial activity of the hemolymph (plasma) and hemocytes (plasma cells) of six brachyuran crabs was investigated against 16 pathogenic strains. Among the 16 strains tested maximum zone of inhibition was recorded in the hemolymph of Hyas araneus against Shigella flexineri.

Use of Fourier Transform Infrared (FTIR) spectroscopy to study cadmium-induced changes in Padina tetrastromatica (Hauck).

The aim of this study is to adopt the approach of metabolic fingerprinting through the use of Fourier Transform Infrared (FTIR) technique to understand changes in the chemical structure in Padina tetrastromatica (Hauck). The marine brown alga under study was grown in two different environmental conditions; in natural seawater (P. tetrastromatica (c)) and in seawater suplemented with 50 ppm of cadmium (P.

New caulerpenyne-derived metabolites of an Elysia sacoglossan from the South Indian coast.

Chemical analysis of the secondary metabolite pattern of the sacoglossan mollusc Elysia cf. expansa, collected along South Indian coasts, showed the presence of the typical Caulerpa-derived sesquiterpene caulerpenyne (1) and two new minor co- occurring metabolites, the compounds dihydrocaulerpenyne (4) and expansinol (5). The chemical characterization of these molecules, structurally related to 1, is reported.

Glycolipids from the red alga Chondria armata (Kutz.) Okamura.

Three distinct fractions containing polar glycolipids (PF(1-3)) were isolated from the chloroform soluble fraction of crude methanolic extract of red alga Chondria armata (Kütz.) Okamura on gel chromatography over Sephadex LH20. Their structure was elucidated by multidimensional nuclear magnetic resonance (NMR) techniques like 1H, 1H correlation spectroscopy (COSY), 1H, 1H total COSY (TOCSY), 1H, 13C heteronuclear multiple quantum coherence (HMQC), and 1H, 13C heteronuclear multiple bond correlation (HMBC) complemented by electrospray ionization mass spectrometry (ESI-MS) in the positive ion mode.