Antiproliferative activity of 18 fish protein hydrolysates was measured on 2 human breast cancer cell lines grown in vitro. Three blue whiting, three cod, three plaice and one salmon hydrolysates ...were identified as significant growth inhibitors on the two cancer cell lines. Preliminary analysis of hydrolysates composition evidenced they contained a complex mixture of free amino acids, peptides with various sizes ranging up to 7
kDa and in a lower proportion, lipids and sodium chloride. RP-HPLC fractionation of fish hydrolysates is currently undertaken to purify anticancer peptides, lipids or other bioactive trace compounds responsible for this antiproliferative activity.
Because of their characteristic living environments, marine organisms produce a variety
of lipids. Fatty acids constitute the essential part of triglycerides and wax esters, which are the
major ...components of fats and oils. Nevertheless, phospholipids and glycolipids have considerable
importance and will be taken into account, especially the latter compounds that excite increasing
interest regarding their promising biological activities. Thus, in addition to the major polyunsaturated
fatty acids (PUFA) such as eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids, a great number
of various fatty acids occur in marine organisms, e.g. saturated, mono- and diunsaturated, branched,
halogenated, hydroxylated, methoxylated, non-methylene-interrupted. Various unprecedented chemical
structures of fatty acids, and lipid-containing fatty acids, have recently been discovered, especially
from the most primitive animals such as sponges and gorgonians. This review of marine lipidology
deals with recent advances in the field of fatty acids since the end of the 1990s. Different approaches
will be followed, mainly developing biomarkers of trophic chains in marine ecosystems and of chemotaxonomic
interest, reporting new structures, especially those with biological activities or biosynthetic interest.
An important part of this review will be devoted to the major PUFA, their relevance to health and
nutrition, their biosynthesis, their sources (usual and promising) and market.
A sulfoglycolipidic fraction (SF) isolated from the red microalga Porphyridium cruentum was analyzed for fatty acid composition and assayed for ability to inhibit, in vitro, the generation of ...superoxide anion in primed leucocytes and the proliferation of a panel of human cancer cell-lines. Results demonstrated that SF contained large amounts of palmitic acid (26.1%), arachidonic acid (C20: 4ω-6, 36.8%), and eicopentaenoic (C20:5ω-3, 16.6%) acids, and noticeable amounts of 16:1n-9 fatty acid (10.5%). It strongly inhibited both the production of superoxide anion generated by peritoneal leukocytes primed with phorbol myristate acetate (IC50: 29.5 μg/mL), and the growth of human colon adenocarcinoma DLD-1 and to a lesser extent of human breast adenocarcinoma MCF-7, human prostate adenocarcinoma PC-3, and human malignant melanoma M4 Beu cell-lines, and therefore might have a chemopreventive or chemotherapeutic potential, or both. It was found markedly more cytotoxic than sulfoquinovosyldiacylglycerols from plant used as a standard (STD), due to a stronger ability to inhibit DNA α-polymerase (IC50: 378 μg/mL, vs 1784 μg/mL for STD). After a 48-h continuous treatment, IC50 values for growth inhibition were in the range of 20−46 μg/mL instead of 94 to >250 μg/mL for STD, and those for inhibition of metabolic activity were in the range of 34−87 μg/mL instead of >250 μg/mL for STD. The higher anti-proliferative effect was observed on colon adenocarcinoma DLD-1 cells, and the weaker effect was observed on breast adenocarcinoma MCF-7. Keywords: Porphyridium cruentum; sulfolipids; sulfoquinovosylacylglycerols (SQAG); fatty acid analysis; anti-inflammatory activity; anti-proliferative activity; solid cancer cell-lines; human carcinoma cells; human melanoma cells
The antibacterial activity of Skeletonema costatum (Grev.) Cleve against aquacultural bacteria was examined. The active compounds, partly purified from an organic phase, were tested against some ...pathogens of shellfish or fish.
The present work aimed to study in rats whether substitution of a low level of fish oil (FO; 2.2% of calories) into a low-fat diet (6.6% of calories from fat as peanut-rape oil or control diet) 1) ...has a tissue-specific effect on insulin signaling pathway and 2) prevents dexamethasone-induced alteration of insulin signaling in liver, muscle, and adipose tissue. Sixteen rats were used for study of insulin signaling, and sixteen rats received an oral glucose load (3 g/kg). Eight rats/group consumed control diet or diet containing FO over 5 wk. Four rats from each group received a daily intraperitoneal injection of saline or dexamethasone (1 mg.kg(-1).day(-1)) for the last 5 days of feeding. In liver, FO decreased phosphatidylinositol 3'-kinase (PI 3'-kinase) activity by 54% compared with control diet. A similar result was obtained in muscle. In both liver and muscle, FO clearly amplified the effect of dexamethasone. FO did not alter early steps of insulin signaling, and in muscle GLUT4 protein content remained unaltered. In adipose tissue, FO increased PI 3'-kinase activity by 74%, whereas dexamethasone decreased it by 65%; inhibition of PI 3'-kinase activity by dexamethasone was similar in rats fed FO or control diet, and GLUT4 protein content was increased by 61% by FO. Glycemic and insulinemic responses to oral glucose were not modified by FO. In conclusion, FO increased PI 3'-kinase activity in adipose tissue while inhibiting it in liver and muscle. The maintenance of whole body glucose homeostasis suggests an important role of adipose tissue for control of glucose homeostasis.
The ban on the use of TBT-based antifouling paints for boats under 25 m in length has lead to a search for new non-toxic antifoulants. One of the most promising alternative technologies to heavy ...metal based antifouling paint is the development of antifouling coatings whose active ingredients are naturally occurring compounds from marine organisms. This is based on the principle that marine organisms also face the problem of the presence of epibionts on their own surfaces. In this study, the antifouling activity of a series of aqueous, ethanolic and dichloromethane extracts from thirty algae from the North East Atlantic coast was investigated. The extracts were tested in laboratory assays against species representative of two major groups of fouling organisms, viz . macroalgae and microalgae. The activity of several extracts was comparable to that of heavy metals and biocides (such as TBTO and CuSO 4 ) currently used in antifouling paints and their lack of toxicity with respect to the larvae of oysters and sea urchins suggests a potential for novel active ingredients.
It is essential to have simple rapid methods for the determination of fatty acid structures. Traditionally, fatty acids are analysed by gas chromatography using their methyl ester derivatives (FAME). ...However, their corresponding mass spectra exhibit molecular ions but are usually devoid of ions indicative of structural features and, notably, the position of double bounds on the aliphatic chains 1. In the most useful approach to structure determination, the carboxyl group is derivatised with a reagent containing a nitrogen atom. Recently, a convenient method for preparing picolinyl esters from intact lipids has been published 2. However, some problems occurred in our laboratory when this method was used, leading to some modifications and optimisation. Thus, hexane and water have been added while sodium bicarbonate has been removed in order to lower contamination. Temperature and length of the reaction have then been optimised in order to get 100% derivatisation for different kinds of lipids (45 °C and 45 min for FAME). Finally, a comparison of the response factors has confirmed the better sensitivity of the picolinyl derivative against FAME (five times more).
In the present work, we questioned the natural or artifactual origin of the large amounts of free fatty acids recovered in lipids from the diatom
Skeletonema costatum. Using rapid cell harvest and a ...very drastic method to extract the lipids, we demonstrated that these lipid patterns rich in free fatty acids were relevant to the degradation of complex lipids. A revised lipid composition of
S. costatum is given which differs from those previously described by the absence of free fatty acids, while the proportion of polar lipids is substantially increased. Membrane lipids are mostly represented and storage lipids are less abundant, since we analysed the cells during their exponential growth phase. However, the fatty acid composition is in agreement with previous data. Polyunsaturated fatty acids (PUFA) consist essentially of 20:5 ω3, 16:3 ω4 and 16:4 ω1, while 16:1 ω7 is the main monousaturated FA. This confirms that, with regard to its lipid composition, the diatom,
S. costatum, provides a good diet for molluscs, particularly through its high proportion of ω3 PUFA. Using this extraction procedure, sterols were found to be identical to previous results but a new compound, a 18:11 fatty alcohol, was detected. The consequences of this reassessement on the lipid compositions of diatoms so far published and their application to the lipid diet of mollusc larvae in aquaculture are discussed.
A simple and efficient methodology to introduce an 1,3-diketone motif from various aldehyde precursors in three steps with good overall yields is described using β-ketosulphone
7
as masked equivalent ...of acetone.
A three-step sequence was studied leading in good yields to 1,3-diketones from aldehydes.
A water-soluble fraction from the marine diatom Haslea ostrearia was capable to inhibit the in vitro replication of HSV-1 in Vero cells with 50% inhibitory concentration (EC50) of 14 micrograms/ml at ...a multiplicity of infection of 0.01 ID50/cells. In addition, this fraction delayed the HIV-1-induced syncitia formation on MT4 cells. At concentrations up to 200 micrograms/ml, no cytotoxicity was observed for both the Vero and MT4 cells. The fraction only inhibited the blood coagulation process at concentrations considerably exceeding the EC50.
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