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Saint-Sauveur-en-Rue, France

Hardouin K.,University of Southern Brittany | Hardouin K.,OLMIX SA | Bedoux G.,University of Southern Brittany | Burlot A.-S.,University of Southern Brittany | And 4 more authors.
Algal Research | Year: 2016

In order to develop innovative methods for the production of bioactive extracts with potential health benefits, enzyme-assisted extraction has been applied for the bioconversion of Ulva armoricana (Ulvales, Ulvophyceae). The extraction yields, chemical composition, the antioxidant and antiviral activities were determined to assess the efficiency of six commercial enzymatic preparations. Endo-protease treatments significantly increased the extraction yields compared to the control. The organic matter, neutral sugar and protein contents were increased in all extracts compared to an extraction with water, up to 2.0-fold, 2.7-fold and 1.75-fold, respectively. The samples prepared by a multiple-mix of glycosyl-hydrolases and an exo-β-1,3(4)-glucanase revealed activities against herpes simplex virus type-1 at the median effective concentration (EC50) of 373.0 ± 20.7 and 320.9 ± 33.6 μg/ml, respectively. These activities were correlated to high amounts of rhamnose, uronic acids and sulfate groups which are the main constituents of ulvans. Free radical scavenging capacity at medium inhibition concentrations (IC50) of 1.8 and 12.5 mg/ml was shown for the extracts produced with endo-protease treatments and 6.0 mg/ml for the sample resulting from the extraction with the multiple-mix of glycosyl-hydrolases. This study reports the antiviral and antioxidant activities of Ulva armoricana extracts produced by enzyme-assisted extraction. © 2016 Elsevier B.V.

Perez-Galvez R.,University of Granada | Garcia-Moreno P.J.,University of Granada | Huong N.T.-M.,2 Nguyen Dinh Chieu Str. | Guadix E.M.,University of Granada | And 2 more authors.
Clean Technologies and Environmental Policy | Year: 2016

The current application of the zero discards policy in EU fisheries poses economic and logistic problems to fishing vessels, which are obliged to retain and preserve unwanted catches on board. The installation of compaction devices on board can effectively reduce the space requirements and the refrigeration loads to store these materials on board. In the current work, the performance of a pilot hydraulic press was optimized to attain a maximal volume reduction (i.e., maximal yield of press liquor) while keeping a reduced pollution load of the liquid effluents. To this end, a designed experiment was conducted where the yield (Y), the content of suspended solids (SS), and the chemical oxygen demand (COD) of the press liquor were related to the main operation parameters of the pilot plant (i.e., number of pressing steps and time of relaxation between consecutive steps). Statistical modeling, coupled to a multiobjective optimization technique (i.e., the weighted-sum method), was employed to find a set of optimal solutions meeting three objectives: maximal Y (i.e., maximal volume reduction of the press cake), and minimal SS and COD of the press waters. This approach concluded that 5 pressing steps and a time of relaxation between 105 and 120 s ensured a low content of SS (0.0170-0.0185 kg solids/kg sardine), while the yield was high (0.1942-0.2001 kg liquid/kg sardine) and COD remained below 24.4 g O2/kg sardine. © 2015 Springer-Verlag.

Le Guillard C.,French Research Institute for Exploitation of the Sea | Le Guillard C.,University of Nantes | Dumay J.,University of Nantes | Donnay-Moreno C.,French Research Institute for Exploitation of the Sea | And 4 more authors.
Algal Research | Year: 2015

The aim of this study was to compare two processes for the extraction of R-phycoerythrin (R-PE) from the red seaweed Grateloupia turuturu: ultrasound-assisted extraction (UAE) and ultrasound-assisted enzymatic hydrolysis (UAEH). Process efficiencies were both evaluated by the yield of R-PE extraction and by the level of liquefaction. Experiments were conducted at 40 and 22 °C, for 6 h, using an enzymatic cocktail and an original ultrasonic flow-through reactor. R-PE appeared very sensitive to temperature, thus 22 °C is strongly recommended for its extraction by UAEH or UAE. However, the higher processing temperature (40 °C) clearly increased the extraction of water-soluble compounds (up to 91% of liquefaction). These two new processes are thus promising alternatives for the extraction of water-soluble components including R-PE, from wet seaweeds, with extraction yields at least similar to conventional solid-liquid extraction. © 2015 Published by Elsevier B.V.

Lahogue V.,University of Southern Brittany | Rehel K.,University of Southern Brittany | Taupin L.,University of Southern Brittany | Haras D.,University of Southern Brittany | Allaume P.,IDMer
Food Chemistry | Year: 2010

To determine the angiotensin-converting enzyme (ACE) inhibitory activity of a fish hydrolysate, different methods were tested. Finally, a sensitive, extraction-free HPLC method using N-(3-[2-furylacryloyl)-Phe-Gly-Gly (FAPGG) as substrate was preferred. This method relies on the UV-titration of the peptide 2-furylacryloyl-l-Phe (FAP) resulting from the hydrolysis of the FAPGG after a chromatographic separation on a reverse phase column. The experimental conditions (enzyme/substrate ratio, incubation time, NaCl concentration) were optimised for linearity, sensitivity and precision. The assay was adequate for the study of ACE inhibition by Captopril, used as reference, and several peptides. Captopril and the fish hydrolysate had IC50 values, respectively of 0.19 ng and 43 μg with standard deviations of 0.09 ng and 5 μg. Afterwards, the determination of the Hill coefficient sustained the hypothesis that active peptides present in the fish hydrolysate were low-molecular weight molecules. This result was confirmed by the activity measurement of the fish hydrolysate fractions obtained by gel filtration. © 2009 Elsevier Ltd. All rights reserved.

Le C.M.,Thai Nguyen University | Donnay-Moreno C.,French Research Institute for Exploitation of the Sea | Bruzac S.,French Research Institute for Exploitation of the Sea | Baron R.,French Research Institute for Exploitation of the Sea | And 2 more authors.
Food Technology and Biotechnology | Year: 2015

Fish sauce production is a very long process and there is a great interest in shortening it. Among the different strategies to speed up this process, the addition of external proteases could be a solution. This study focuses on the effect of two commercial enzymes (Protamex and Protex 51FP) on the proteolysis of two fish species traditionally converted into fish sauce: sardine and anchovy, by comparison with classical autolysis. Hydrolysis reactions were conducted with fresh fish at a temperature of 30 °C and under different saline conditions (from 0 to 30 % NaCl). Hydrolysis degree and liquefaction of the raw material were used to follow the process. As expected, the proteolysis decreased with increasing amount of salt. Regarding the fish species, higher rate of liquefaction and higher hydrolysis degree were obtained with anchovy. Between the two proteases, Protex 51FP gave better results with both fish types. This study demonstrates that the addition of commercial proteases could be helpful for the liquefaction of fish and cleavage of peptide bonds that occur during fish sauce production and thus speed up the production process.

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