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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.