Consulta: creatorFacets:"Fleurence, Joel"
Registros recuperados: 7
Data/hora: 13/06/2024 01:19:57

Ultrasound-assisted extraction of R-phycoerythrin from Grateloupia turuturu with and without enzyme addition
Provedor de dados: 5
Autores: Le Guillard, Cecile; Dumay, Justine; Donnay-moreno, Claire; Bruzac, Sandrine; Ragon, Jean-yves; Fleurence, Joel; Berge, Jean-pascal.
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...
Tipo: Text
Palavras-chave: Seaweed; Grateloupia turuturu; R-phycoerythrin; Ultrasound-assisted extraction; Ultrasound-assisted enzymatic hydrolysis; Liquefaction.
Ano: 2015
URL: http://archimer.ifremer.fr/doc/00292/40332/39993.pdf

Proteolytic potential in white muscle of sea bass (Dicentrarchus labrax L.) during post mortem storage on ice: time-dependent changes in the activity of the components of the calpain system
Provedor de dados: 5
Autores: Delbarre Ladrat, Christine; Verrez-bagnis, Veronique; Noel, Joelle; Fleurence, Joel.
The variations in the amounts of milli-calpain and its specific inhibitor in the white muscle of sea bass (Dicentrarchus labrax) during storage at 4 degreesC for up to 7 days were determined after separation by hydrophobic chromatography on a Phenyl Sepharose vel. There was a significant decline in post-slaughter m-calpain activity with an important inter-individual variability in the rate of decrease of the total activity. In contrast with the calpastatin of mammalian post mortem muscles, calpastatin remained constant within fish muscles after death. The initial levels of protease and inhibitor activities, and their behaviour through post mortem storage. are discussed and implications for the mechanism of tenderisation of fish muscle are suggested. (C)...
Tipo: Text
Palavras-chave: Proteolysis; Post mortem; Fish muscle; Calpain; Calpastatin; Neutral calcium dependent protease.
Ano: 2004
URL: http://archimer.ifremer.fr/doc/2004/publication-1683.pdf

Relative contribution of calpain and cathepsins to protein degradation in muscle of sea bass (Dicentrarchus labrax L.)
Provedor de dados: 5
Autores: Delbarre Ladrat, Christine; Verrez-bagnis, Veronique; Noel, Joelle; Fleurence, Joel.
The effects of a milli(m)-calpain isolated from the white muscle of sea bass (Dicentrarchus labrax L) and commercial cathepsins B, D and L, used in combination on the myofibrillar and sarcoplasmic proteins were examined. Protein digestion was first performed by the endogenous m-calpain, (luring 2 h before the addition of a mixture of cathepsins B, D and L and a further incubation up to 22 h. Calpain degraded a 27 kDa sarcoplasmic component as well as myosin heavy chain, a-actinin, desmin and a 32 kDa component from the myofibrillar fraction. A 97 kDa component and the assumed creatine kinase-aldolase doublet were degraded during the incubation of sarcoplasmic proteins with the cathepsin mixture while, among the myofibrillar proteins, myosin, actin,...
Tipo: Text
Palavras-chave: Postmortem aging; Fish muscle; Proteolysis; Cathepsins; Neutral calcium dependent protease.
Ano: 2004
URL: http://archimer.ifremer.fr/doc/2004/publication-1682.pdf

Seasonal variation in the antivibrio activity of two organic extracts from two red seaweed: Palmaria palmata and the introduced Grateloupia turuturu against the abalone pathogen Vibrio harveyi
Provedor de dados: 5
Autores: Garcia-bueno, Nuria; Dumay, Justine; Guerin, Thomas; Turpin, Vincent; Paillard, Christine; Stiger-pouvreau, Valerie; Pouchus, Yves-francois; Aitor Marin-atucha, Arnaldo; Decottignies, Priscilla; Fleurence, Joel.
The wide polarity range and highly polar compounds of two selected red seaweed, Grateloupia turuturu and Palmaria palmata were extracted using two different types of solvent, dichloromethane/methanol and methanol/water. Monthly in vitro antibacterial activities were studied using the microplate method against the marine bacteria Vibrio harveyi strain ORM4, known to infect abalone. Inhibition, slowdown and delay of Vibrio harveyi growth were investigated. Polar compounds of seaweed showed an activity against the abalone pathogen. The best activity was recorded from P. palmata collected in spring, with an inhibition of 7.9% of the bacterial growth. Preliminary 1H NMR profiles identified the differences between the extracts.
Tipo: Text
Palavras-chave: Antibacterial activity; Abalone disease; Haliotis tuberculata; Red seaweed; Vibrio harveyi.
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00617/72875/71929.pdf

In vitro proteolysis of myofibrillar and sarcoplasmic proteins of white muscle of sea bass (Dicentrarchus labrax L.): effects of cathepsins B, D and L
Provedor de dados: 5
Autores: Delbarre Ladrat, Christine; Verrez-bagnis, Veronique; Noel, Joelle; Fleurence, Joel.
The purpose of this study was to obtain additional information regarding proteolysis mechanisms and disorganization of fish myofibrils resulting in a loss of flesh quality. The ability of cathepsins to degrade in vitro myofibrillar and sarcoplasmic proteins from fish muscle was investigated in order to explain their role in post mortem softening. This led to the identification of substrates of the enzymes. Cathepsins degraded myosin heavy chain and a-actinin. Tropomyosin and actin were only susceptible to the action of cathepsin L. Troponin T (assumed 32 kDa component) was resistant only to the action of cathepsin D. Desmin was degraded by cathepsins B and L. Slight changes of some other myofibrillar or cytosolic proteins were also observed (creatine...
Tipo: Text
Palavras-chave: Post mortem degradation; Fish muscle proteins; Cathepsins; In vitro proteolysis.
Ano: 2003
URL: http://archimer.ifremer.fr/doc/2003/publication-1684.pdf

In vitro proteolysis of myofibrillar and sarcoplasmic proteins of European sea bass (Dicentrarchus Labrax L) by an endogenous m-calpain
Provedor de dados: 5
Autores: Verrez-bagnis, Veronique; Delbarre Ladrat, Christine; Noel, Joelle; Fleurence, Joel.
The effects of m-calpain isolated from the skeletal muscle of sea bass on sarcoplasmic and myofibrillar proteins isolated from the same tissue were examined in vitro. Incubation of sarcoplasmic proteins with m-calpain resulted in only a slight decrease (0.7 kDa) in the molecular weight (MW) of a 26.5 kDa protein. Degradation of myofibrils, monitored by quantification of TCA-soluble peptides generated, resulted in the maximum amount of peptides being generated after 1 h of incubation at 25degreesC. Noticeable modifications in the SDS-PAGE profile of digested myofibrils were observed, including partial denaturation of myosin heavy chain and the release of tropomyosin, similar to69 and similar to27 kDa doublet bands and a few polypeptides of MW lower than 20...
Tipo: Text
Palavras-chave: Dicentrarchus labrax L; Proteolysis; Sarcoplasmic protein; Calpain; Myofibrillar protein.
Ano: 2002
URL: http://archimer.ifremer.fr/doc/2002/publication-1108.pdf

Soft liquefaction of the red seaweed Grateloupia turuturu Yamada by ultrasound-assisted enzymatic hydrolysis process
Provedor de dados: 5
Autores: Le Guillard, Cecile; Berge, Jean-pascal; Donnay-moreno, Claire; Bruzac, Sandrine; Ragon, Jean-yves; Baron, Regis; Fleurence, Joel; Dumay, Justine.
Ultrasound-assisted enzymatic hydrolysis is a recent process, increasingly employed for plant biomass liquefaction and the recovery of soluble biomolecules. However, to our knowledge, it has never been used on seaweeds, particularly wet ones. The aim of this study was to compare the efficiency of three processes on the liquefaction of the red seaweed Grateloupia turuturu Yamada: enzyme-assisted extraction (EAE), ultrasound-assisted extraction (UAE), and their combination, ultrasound-assisted enzymatic hydrolysis (UAEH). These comparisons will allow the identification as to which process achieves the highest extraction yield of water-soluble compounds. For this purpose, experiments were conducted at 40 °C for 6 h using an enzymatic cocktail of four...
Tipo: Text
Palavras-chave: Ultrasound-assisted enzymatic hydrolysis; Enzymatic hydrolysis; Ultrasound; Liquefaction; Algae; Grateloupia turuturu.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00308/41877/44316.pdf