An extract of the marine alga Alaria esculenta modulates α-synuclein folding and amyloid formation.

The conversion of α-synuclein from its natively unfolded and α-helical tetrameric forms to an amyloid conformation is central to the emergence of Parkinson's disease. Therefore, prevention of this conversion may offer an effective way of avoiding the onset of this disease or delaying its progress. At different concentrations, an aqueous extract from the edible winged kelp (Alaria esculenta), was shown to lower and to raise the melting point of α-synuclein.

Analysis of Betaines from Marine Algae Using LC-MS-MS.

Betaines are a class of quaternary ammonium compounds found in marine algae that can act as osmolytes and/or affect gene expression, and therefore improve plant tolerance to stresses such as temperature extremes, drought, and salinity when applied to agricultural crops. In humans, glycine betaine acts as a methyl donor and has been shown to protect internal organs, improve vascular risk factors, and enhance sport performance. Here we describe a sensitive LC-MS-MS method for the baseline separation and quantification of four betaines found in algae, namely, glycine betaine, δ-aminovaleric acid betaine, γ-aminobutyric acid betaine, and laminine.

Characterization of Phlorotannins from Brown Algae by LC-HRMS.

Phlorotannins are a class of polyphenols found in brown seaweeds that have significant potential for use as therapeutics, owing to their wide range of bioactivities. Molecular characterization of phlorotannin-enriched extracts is challenging due to the extreme sample complexity and the wide range of molecular weights observed. Herein, we describe a method for characterizing phlorotannins employing ultrahigh-pressure liquid chromatography (UHPLC) operating in hydrophilic interaction liquid chromatography (HILIC) mode combined with high-resolution mass spectrometry (HRMS).

Profiling phlorotannins in brown macroalgae by liquid chromatography-high resolution mass spectrometry.

Introduction: Phlorotannins, phenolic compounds produced exclusively by Phaeophyceae (brown algae), have recently been associated with a wide variety of beneficial bioactivities. Several studies have measured the total phenolic content in extracts from various species, but little characterisation of individual phlorotannin components has been demonstrated.

Objective: The purpose of this study was to develop a liquid chromatography-mass spectrometry (LC-MS) based method for rapid profiling of phlorotannins in brown algae.

Investigations into the toxicology of spirolides, a group of marine phycotoxins.

Spirolides are marine phycotoxins produced by the dinoflagellates Alexandrium ostenfeldii and A. peruvianum. Here we report that 13-desmethyl spirolide C shows little cytotoxicity when incubated with various cultured mammalian cell lines.

Ursolic acid and its esters: occurrence in cranberries and other Vaccinium fruit and effects on matrix metalloproteinase activity in DU145 prostate tumor cells.

Background: Ursolic acid and its cis- and trans-3-O-p-hydroxycinnamoyl esters have been identified as constituents of American cranberries (Vaccinium macrocarpon), which inhibit tumor cell proliferation. Since the compounds may contribute to berry anticancer properties, their content in cranberries, selected cranberry products, and three other Vaccinium species (V. oxycoccus, V.

Characterization of a Dispiroketal Spirolide Subclass from Alexandrium ostenfeldii.

A new subclass of spirolide marine toxins, represented by spirolides H (1) and I (2), were isolated from the marine dinoflagellate Alexandrium ostenfeldii. Spirolides H and I are structurally distinct from other spirolides in that they contain a 5:6 dispiroketal ring system rather than the trispiroketal ring system characteristic of previously isolated spirolides. The structures were assigned using a combination of spectrometric and spectroscopic techniques.

Dietary Ascophyllum nodosum increases urinary excretion of tricarboxylic acid cycle intermediates in male Sprague-dawley rats.

We used a (1)H NMR-based metabonomics approach to examine the physiological effects of the seaweed Ascophyllum nodosum in a mammalian model, assess the dosage level required to elicit a response in the urinary profile, and identify potential toxic effects. Male Sprague-Dawley rats (n = 6/group) were fed a control or 5, 10, or 15% freeze-dried, ground A. nodosum diet for 4 wk.

Myxinidin, a novel antimicrobial peptide from the epidermal mucus of hagfish, Myxine glutinosa L.

Fish epidermal mucus contains innate immune components that provide a first line of defense against various infectious pathogens. This study reports the bioassay-guided fractionation and characterization of a novel antimicrobial peptide, myxinidin, from the acidic epidermal mucus extract of hagfish (Myxine glutinosa L.).

Comparison of antimicrobial activity in the epidermal mucus extracts of fish.

The mucus layer on the surface of fish consists of several antimicrobial agents that provide a first line of defense against invading pathogens. To date, little is known about the antimicrobial properties of the mucus of Arctic char (Salvelinus alpinus), brook trout (S. fontinalis), koi carp (Cyprinus carpio sub sp.

Silyamandin, a new flavonolignan isolated from milk thistle tinctures.

Our investigations into the stability of tincture preparations of milk thistle fruit [ Silybum marianum L. Gaertn. (Asteraceae)] have led to the characterization of a new flavonolignan 4-(4-hydroxy-3-methoxyphenyl)-7-[(2 R,3 R)-3,5,7-trihydroxy-4-oxochroman-2-yl]-1-oxo-1,3,3a,4,5,7a-hexahydro-2-benzofuran-5-carboxylic acid called silyamandin (1).

A comparative study on innate immune parameters in the epidermal mucus of various fish species.

Fish epidermal mucus and its components provide the first line of defense against pathogens. Little is known about the role of epidermal mucus enzymes in the innate immune system of fish species such as Arctic char (Salvelinus alpinus), brook trout (S. fontinalis), koi carp(Cyprinus carpio), striped bass (Morone saxatilis), haddock, (Melanogrammus aeglefinus), Atlantic cod (Gadus morhua) and hagfish (Myxine glutinosa).

Biosynthesis of 13-desmethyl spirolide C by the dinoflagellate Alexandrium ostenfeldii.

Biosynthetic origins of the cyclic imine toxin 13-desmethyl spirolide C were determined by supplementing cultures of the toxigenic dinoflagellate Alexandrium ostenfeldii with stable isotope-labeled precursors [1,2-13C2]acetate, [1-13C]acetate, [2-13CD3]acetate, and [1,2-13C2,15N]glycine and measuring the incorporation patterns by 13C NMR spectroscopy. Despite partial scrambling of the acetate labels, the results show that most carbons of the macrocycle are polyketide-derived and that glycine is incorporated as an intact unit into the cyclic imine moiety. This work represents the first conclusive evidence that such cyclic imine toxins are polyketides and provides support for biosynthetic pathways previously defined for other polyether dinoflagellate toxins.

Spirolides isolated from Danish strains of the toxigenic dinoflagellate Alexandrium ostenfeldii.

Using LC/MS methodology, spirolides were detected in two clonal isolates of Alexandrium ostenfeldii isolated from Limfjorden, Denmark. Examination of the LC/MS profiles of extracts from these Danish cultures revealed the presence of two dominant peaks representing two previously unidentified spirolide components and one minor peak identified as the previously reported desmethyl spirolide C (1). Culturing of these clonal strains, LF 37 and LF 38, of A.

Blueberry flavonoids inhibit matrix metalloproteinase activity in DU145 human prostate cancer cells.

Regulation of the matrix metalloproteinases (MMPs), the major mediators of extracellular matrix (ECM) degradation, is crucial to regulate ECM proteolysis, which is important in metastasis. This study examined the effects of 3 flavonoid-enriched fractions (a crude fraction, an anthocyanin-enriched fraction, and a proanthocyanidin-enriched fraction), which were prepared from lowbush blueberries (Vaccinium angustifolium), on MMP activity in DU145 human prostate cancer cells in vitro. Using gelatin gel electrophoresis, MMP activity was evaluated from cells after 24-hr exposure to blueberry fractions.

Inhibition of matrix metalloproteinase activity in DU145 human prostate cancer cells by flavonoids from lowbush blueberry (Vaccinium angustifolium): possible roles for protein kinase C and mitogen-activated protein-kinase-mediated events.

Regulation of the matrix metalloproteinases (MMPs) is crucial to regulate extracellular matrix (ECM) proteolysis which is important in metastasis. This study investigated the mechanism(s) by which three flavonoid-enriched fractions from lowbush blueberry (Vaccinium angustifolium) down-regulate MMP activity in DU145 human prostate cancer cells. Metalloproteinase activity was evaluated from cells exposed to "crude," anthocyanin-enriched (AN) and proanthocyanidin-enriched (PAC) fractions.

Metabolic changes in Atlantic salmon exposed to Aeromonas salmonicida detected by 1H-nuclear magnetic resonance spectroscopy of plasma.

1H-NMR (nuclear magnetic resonance)-based chemometric methods have been applied for the first time to investigate changes in the plasma metabolite profiles of Atlantic salmon Salmo salar as a result of exposure to Aeromonas salmonicida subsp. salmonicida, a Gram-negative bacterium that is the etiological agent of furunculosis. Plasma samples were obtained from salmon that survived 21 d post exposure to A.

Detection and identification of spirolides in norwegian shellfish and plankton.

Mussels sampled in the spring of 2002 and 2003 from Skjer, a location in Sognefjord, Norway, tested positive in the mouse bioassay for lipophilic toxins. The symptoms, which included cramps, jumping, and short survival times (as low as 4 min), were not characteristic of toxins previously observed in Norway. A survey of the algae present at the aquaculture sites showed that the toxicity correlated with blooms of Alexandrium ostenfeldii.

Identification of triterpene hydroxycinnamates with in vitro antitumor activity from whole cranberry fruit (Vaccinium macrocarpon).

Bioactivity-guided fractionation of cranberry fruit was used to determine the identity of triterpenoid esters from Vaccinium macrocarpon, which inhibit tumor cell growth and may play a role in cancer prevention. In our previous study, a fraction from whole fruit exhibited tumor cell growth inhibition in vitro. The major components of this fraction were isolated by chromatographic separation of ethyl acetate extracts, purified by semipreparative HPLC, and identified by NMR as cis- (1) and trans- (2) isomers of 3-O-p-hydroxycinnamoyl ursolic acid.