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Rio de Janeiro, Brazil

Buarque D.S.,Laboratorio Of Enzimologia Labenz | Castro P.F.,Embrapa Meio Norte | Santos F.M.S.,Laboratorio Of Enzimologia Labenz | Amaral I.P.G.,Laboratorio Of Enzimologia Labenz | And 4 more authors.
Aquaculture Nutrition | Year: 2010

The aim of this study was to examine proteinases and peptidases from the hepatopancreas of two sub-adult stages of Farfantepenaeus subtilis: SAS6 (5.93 ± 0.69 g wet weight) and SAS13 (13.26 ± 0.60 g wet weight). Trypsin and chymotrypsin activity was higher in the extract from the SAS6 individuals (P < 0.05). The highest activity among aminoacyl-β-naphthylamide substrates was found using alanine-, arginine-, leucine-and lysine-β-naphthylamide. There was a positive correlation between the recommended concentration of essential amino acids in penaeid shrimp feed and aminopeptidase activity in both sub-adult stages. Proteolytic activity of F. subtilis was strongly inhibited by specific trypsin inhibitors. The optimal temperature for trypsin, chymotrypsin and leucine aminopeptidase activity was between 45 and 55 °C. Six and seven bands were found in caseinolytic zymograms for SAS6 and SAS13 respectively. All bands were inhibited by phenylmethylsulfonyl fluoride in both sub-adult stages. The use of tosyl-lysine-chloromethyl-ketone and benzamidine caused strong inhibition of the proteolytic bands. Trypsin and chymotrypsin activity was the main difference observed between the protease pattern of SAS6 and SAS13 F. subtilis. © 2009 Blackwell Publishing Ltd.

Santos S.D.,Federal University of Pernambuco | Santos S.D.,Laboratorio Of Enzimologia Labenz | Cahu T.B.,Federal University of Pernambuco | Cahu T.B.,Laboratorio Of Enzimologia Labenz | And 6 more authors.
Journal of Food Science | Year: 2012

Astaxanthin is a carotenoid known to have antioxidant and antiinflammatory properties. This study examined if shrimp astaxanthin modulates the production of superoxide (O- 2), nitric oxide (NO), and tumor necrosis factor-α (TNF-α) in rat alveolar macrophages. The oxidative effect was induced by phorbol myristate acetate and lipopolysacharide. The treatment was compared with superoxide dismutase, butylated hydroxytoluene, commercial astaxanthin, N-nitric-L-arginine methyl ester and L- canavanine, all administered as a 43.5-μg/mL dose in the presence of 1% EtOH/0.5% DMSO. All treatments maintained cell viability, as observed in the MTT assay, and shrimp extract increased the viable alveolar macrophages to 168%. Shrimp extract and commercial astaxanthin showed a suppressive effect on the generation of both free radicals O- 2 and NO, while purified shrimp astaxanthin was specific to NO. TNF-α secretion was correlated with NO production. However, in this correlation, the shrimp extract completely inhibited TNF-α. In the light of these findings, the antioxidant action demonstrated in this study suggests that the shrimp extract could be considered as a promising source of bioactive substances with antioxidant and anti-inflammatory activity. © 2012 Institute of Food Technologists®.

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