Economic, social, and environmental assessment of farming Nile tilapia in net-cages in a reservoir in hot semi-arid region during an extended drought event.

Water reservoirs have been constructed in hot semi-arid regions, which may be used to produce fish. The present study described major features of the economic, social, and environmental characteristics of a net-cage Nile tilapia production system, stocked with 100 and 120 fish/m, implemented in a reservoir in the hot semi-arid region of Brazil during an extended drought event. The production cycle was reduced from 6-8 to 4 months because of the lack of water in the reservoir.

Bioactivity of the Protein Hydrolysates Obtained from the Most Abundant Crustacean Bycatch.

The animals from bycatch of the shrimp fisheries can be a source of natural products and bioactive compounds. Thus, the present study aimed to evaluate the bioactivity of protein hydrolysates prepared from the two most abundant crabs from the bycatch of shrimp fisheries in Brazil (Callinectes ornatus and Hepatus pudibundus). Samples of C.

Preparation and Characterization of Microcapsules Containing Antioxidant Fish Protein Hydrolysates: a New Use of Bycatch in Brazil.

In this study, we evaluated the effect of complexation and microencapsulation with pea protein on the antioxidant activity of protein hydrolysates from bycatch in Brazil. The zeta potential values of complexes changed from negative to positive with the increase of pea protein as a result of positively charged complexes formation. The increase in the ratio of pea protein/hydrolysates also resulted in increased turbidity in all samples.

Biological activities of the protein hydrolysate obtained from two fishes common in the fisheries bycatch.

Shrimp trawling is an important socio-economic activity; however, the bycatch can be problematic to the environment. Thus, the present study investigated potential uses of the bycatch to generate value-added products. The biological activity of the protein hydrolysates obtained from the two most abundant fish species (Micropogonias furnieri and Paralonchurus brasiliensis) was evaluated.

Nitrate acute toxicity to post larvae and juveniles of Macrobrachium amazonicum (Heller, 1862).

The objective was to determine the median lethal concentration (LC) of nitrate for post-larvae and juveniles of Macrobrachium amazonicum exposed for 96 h, and to identify histopathological alterations in the gills of juveniles exposed to nitrate. Post-larvae and juveniles of M. amazonicum were exposed to seven different concentrations of nitrate (0, 50, 100, 500, 1000, 1500 and 2000 mg.

Chemical Profile of the Sulphated Saponins from the Starfish Luidia senegalensis Collected as by-Catch Fauna in Brazilian Coast.

The by-catch fauna of the shrimp fishery includes a number of marine invertebrates that are discarded because they do not have commercial value. In order to try to add some value to these materials, we analyzed the chemical composition of the starfish Luidia senegalensis collected in the Brazilian coast as a consequence of the trawling fishery method. In order to access their chemical composition, we used a combination of solid phase extraction (SPE) followed by ultra-high performance liquid chromatography coupled to electrospray ionization ion trap tandem mass spectrometry (UPLC-ESI-IT-MS).

Subcellular localization and kinetic characterization of a gill (Na+, K+)-ATPase from the giant freshwater prawn Macrobrachium rosenbergii.

The stimulation by Mg(2+), Na(+), K(+), NH4 (+), and ATP of (Na(+), K(+))-ATPase activity in a gill microsomal fraction from the freshwater prawn Macrobrachium rosenbergii was examined. Immunofluorescence labeling revealed that the (Na(+), K(+))-ATPase α-subunit is distributed predominantly within the intralamellar septum, while Western blotting revealed a single α-subunit isoform of about 108 kDa M r. Under saturating Mg(2+), Na(+), and K(+) concentrations, the enzyme hydrolyzed ATP, obeying cooperative kinetics with V(M) = 115.

Kinetic analysis of gill (Na⁺,K⁺)-ATPase activity in selected ontogenetic stages of the Amazon River shrimp, Macrobrachium amazonicum (Decapoda, Palaemonidae): interactions at ATP- and cation-binding sites.

We investigated modulation by ATP, Mg²⁺, Na⁺, K⁺ and NH₄⁺ and inhibition by ouabain of (Na⁺,K⁺)-ATPase activity in microsomal homogenates of whole zoeae I and decapodid III (formerly zoea IX) and whole-body and gill homogenates of juvenile and adult Amazon River shrimps, Macrobrachium amazonicum. (Na⁺,K⁺)-ATPase-specific activity was increased twofold in decapodid III compared to zoea I, juveniles and adults, suggesting an important role in this ontogenetic stage. The apparent affinity for ATP (K(M) = 0.