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Seaweeds are well recognized as a potential protein source. The edible green seaweed, Ulva sp., is abundant in the Brittany Coast, France. This study examined the extraction of proteins and glycoproteins from this seaweed. Four different extraction procedures (Procedure 1: deionized water, DW; Procedure 2: lysis solution 1 (LS1) containing 8 M urea, 2% Tween 20, 2% Triton X-100, 30 mM dithiothreitol, and 1% polyvinylpyrolidine; Procedure 3: lysis solution 2 (LS2) containing 50 mM Tris-HCl buffer pH 8, 10 mM EDTA, 2 mM Na2S2O5, and 1% Triton X-100; Procedure 4: 50 mM Tris-HCl buffer, pH 8) were applied to extract proteins from Ulva sp. in Brittany. The protein contents (%, dry basis) in the above extracts from Procedures 1–4 were 4.36 ± 0.21, 11.88 ± 0.23, 10.34 ± 0.35, and 3.58 ± 0.48, respectively. Moreover, electrophoresis (SDS-PAGE) revealed that the protein profile varies with season. Three glycoprotein-rich fractions, namely, GP-1 (from Procedure GP1), GP-2-DA, and GP-2-DS (from Procedure GP2), were extracted from Ulva sp. GP-1 and GP-2-DA fractions have a higher protein content than neutral sugars, while GP-2-DS contains a higher amount of neutral sugars than proteins. Matrix-assisted laser desorption ionization-time of flight/mass spectrometry (MALDI-TOF/MS) technique was applied to further proteomic analysis of each glycoprotein-rich fraction. GP-2-DS was hydrolyzed with protease enzyme to confirm the availability of proteins, and interestingly, the particular hydrolysate shows no original peaks in the MALDI-TOF/MS analysis. All three glycoprotein-rich fractions show no cytotoxicity in Vero cells at the tested concentration (500 mg dw mL−1). Collectively, these results revealed that the extractable protein content and protein profile of Ulva sp. differ according to the extraction liquid system and the season. The utilization and value addition of proliferative Ulva sp. in Brittany as a protein source is promising but needs to consider the seasonal change of the protein profile.

International audience; Seaweeds are potentially excellent sources of bio-active metabolites that could represent useful leads in the de-velopment of new functional ingredients in pharmaceuticaland cosmetic industries. In the last decade, new marinebioprocess technologies have allowed the isolation of sub-stances with biological properties. The brown algaSargassum muticum (Yendo) Fensholt (Ochrophyta) was en-zymatically hydrolyzed to prepare water-soluble extracts byusing six different commercially available carbohydrate-degrading enzymes and two proteases. Evaluation of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antiox-idant power (FRAP) antioxidant, tyrosinase, elastase, and bio-film inhibition, antibacterial and antiviral activities as well asevaluation of cytotoxicity were realized for each extract. Totalphenolic content was measured for extract characterization,and solid-phase extraction was useful to purify the enzymaticextract. Soluble total phenolic content of S. muticumViscozyme extract was highest with 6.4% of dry weight.Enzymatic Celluclast and Viscozyme extracts had the lowestvalue of DPPH IC50 indicating a strong antiradical activity,0.6 mg mL−1, in comparison with other enzymes. The ferricreducing antioxidant power ranged between 48.7 μM Fe 2+ Eq,digested with Viscozyme, and 60.8 μM Fe 2+ Eq, digested withAmyloglucosidase. Tyrosinase inhibition activity ofS. muticum Neutrase extract was 41.3% higher compared toother enzymes. Elastase inhibition activity of S. muticumShearzyme extract had highest activity (32.8%). All enzymat-ic extracts showed no cytotoxic effect towards the kidney Verocells. Meanwhile, only S. muticum Neutrase and Alcalase ex-tracts exhibited potential antiviral activity. In addition,S. muticum Viscozyme and Shearzyme extracts showed prom-ising activity in suppressing the biofilm formation againstPseudomonas aeruginosa and Escherichia coli, respectively. Purification of S. muticum Viscozyme extracts by solid-phaseextraction managed to concentrate the phenolic content andimprove the bioactivity. These results indicate the promisingpotential of enzyme-assisted followed by solid-phase extrac-tion in recovering phenolic content and in improving itsbioactivity.

International audience; This field study is intended to propose a global methodology to assess and monitor the water quality of the gulf of Morbihan, a littoral ecosystem under increasing anthropic pressure. To this end, the Locmariaquer site, where Crassostrea gigas is extensively cultivated, was selected to perform a one-year follow-up of tissular glutathione S-transferase and acetylcholinesterase specific activities in this filter feeder organism. Calculation of an integrated index, corresponding to the ratio of the two enzymes activities, allowed to discriminate from the environmental noise, several clusters which could be representative environmental stress, potentially latent pollution. Moreover, the estrogenic activity was assessed in water samples collected at Locmariaquer and other strategic sites of the gulf. The results evidenced a low estrogenic-disrupting compound contamination of waters. Overall, this methodology produced an accurate outlook of a basal state for the gulf and could be developed in the context of a chronic monitoring of this site.

Exopolysaccharides (EPS) were extracted from a sponge, Celtodoryx girardae recently discovered in the Golfe du Morbihan in 2000. Sponge samples were collected monthly from November 2007 to May 2008. SEC analysis of EPS samples showed that they exhibit a unique molecular weight of approximately 800 kDa. However, infrared analysis revealed that structural seasonal variations occur. EPS fractions also exhibit significant sulphate contents and were screened in vitro for a potential antiviral activity against Herpes simplex virus type 1 (HSV-1). The best result was obtained with a sample collected in January which exhibits an EC(50) of 5.9 microg/mL without cytotoxicity on the Vero cell line. Experiments carried out to elucidate the mechanism of the EPS showed that the sulphated groups of EPS interact with the glycoproteins on the surface of the virus' membrane.

International audience; Objective To investigate phenolics, fatty acids composition and biological activities of various extracts and fractions of Malaysian Aaptos aaptos. Methods Fatty acid methyl ester was analyzed by gas chromatography-flame ionization detector. Antioxidant activity was determined using 2,2-diphenyl-picrylhydrazyl radical scavenging assay and total phenolics content by Folin-Ciocalteu procedure. Vera cells viability was evaluated using methyl thiazole tetrazolium and the inactivation of herpes simplex virus type 1 by neutral red uptake assay. p-Hydroxybenzamide isolated by column chromatography was characterized by utilizing nuclear magnetic resonance spectroscopy and electron impact mass spectrometry. Results The chloroform, ethyl acetate and methanol extracts of Aaptos aaptos produced higher portions of straight-chain saturated fatty acid, while hexane extract mainly consisted of unsaturated fatty acid. The five majors of fatty acid methyl ester were identified as behenic acid, cis-10-heptadecenoic acid and cis-10-pentadecenoic acids, palmitic acid and tricosanoic acid. In addition, among all organic extracts, chloroform extract inactivated herpes simplex virus type 1 while exhibited weak cytotoxic activity against normal Vero cells and also exhibited strong cytotoxic activity on HL-60, MCF-7, K562, CEM-SS and WEHI-3B cells. A phenolic compound, p-hydroxybenzamide was also isolated from the sponge. Conclusions Aaptos aaptos could be a source to derive the potential antiviral and anticancer agents. However, further studies are needed to determine the mechanism involved in the process.