995 resultados para Litopenaeus Vannamei. Heparina. Heparinóide. Peritonite. Inflamação. Atividade Antimigratória
Resumo:
O objetivo deste trabalho foi avaliar a remoção de compostos nitrogenados e fosfatados e da carga orgânica poluidora oriunda de cultivo heterotrófico de camarão marinho, por meio de reator anaeróbico. Foi construído um reator com fluxo ascendente, em que os efluentes de entrada e saída foram avaliados continuamente durante 120 horas, com três repetições. Os parâmetros físicos e químicos avaliados foram: temperatura, pH, condutividade, ortofosfato, nitrito, nitrato, amônia, demanda química de oxigênio e sólidos totais. O reator permaneceu estável, com boas condições de retenção de sólidos. O reator anaeróbico removeu 96,7% do nitrogênio amoniacal e 91% de ortofosfatos dos efluentes de cultivo de camarão marinho, o que mostra que os efluentes tratados estão dentro dos limites estabelecidos pela legislação.
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A extração de pigmentos carotenóides constitui uma possível alternativa, de grande agregação de valor, para o aproveitamento da cabeça do camarão Litopenaeus vannamei. O objetivo do presente trabalho foi a identificação, a extração e a quantificação dos principais pigmentos desta matéria-prima, coletados a partir de uma planta de beneficiamento de camarão no Ceará - Brasil. Após cocção dos resíduos a 100 °C, na proporção 1:2 cabeça de camarão e água durante 15 minutos, obteve-se uma pasta de pigmentos brutos extraindo-se os carotenóides com acetona resfriada e, posteriormente, com hexano, obtendo a fase pigmento-hexano. Obteve-se também a fase DMSO, após o material ser particionado com dimetilsulfóxido, e uma fração acidificada. Estas frações sofreram evaporação e secagem, sendo os carotenóides identificados em coluna aberta, utilizando-se o parâmetro de eluição das frações, o espectro de absorção visível e o valor de Rf na camada delgada de sílica gel. Os espectros de absorção de cada fração foram obtidos a 350 a 550 nm e quantificados por cromatografia de camada delgada. Para o cálculo de carotenóides totais (37,62 µg.g-1 da pasta de pigmentos), utilizou-se o somatório das frações hexano, DMSO e acidificada, e coeficientes de extinção 2592, 2100 e 1690 referentes ao beta-caroteno, astaxantina e astaceno, respectivamente. A astaxantina foi o pigmento mais abundante (45,5%), seguido do beta-caroteno-5,6-epóxido (33,5%) e do astaceno (21,0%).
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Aquaculture is a form of agriculture that involves the propagation, cultivation and marketing of aquatic plants and animals in a controlled environment (Swann, 1992). After growing steadily, particularly in the last four decades, aquaculture is for the first time set to contribute half of the fish consumed by the human population worldwide. Given the projected population growth over the next two decades, it is estimated that at least an additional 40 million tonnes of aquatic food will be required by 2030 to maintain the current per capita consumption (FAO, 2006). Capture fisheries and aquaculture supplied the world with about 110 million tonnes of food fish in 2006. Of this total, aquaculture accounted for 47 percent (FAO, 2009). Globally, penaeid shrimp culture ranks sixth in terms of quantity and second in terms of value amongst all taxonomic groups of aquatic animals cultivated (FAO, 2006). In places where warm-water aquaculture was possible black tiger shrimp, Penaeus monodon became the preferred variety of shrimp cultivar owing to its fast growth, seed availability and importantly due to high prices it fetches (Pechmanee, 1997). World shrimp production is dominated by P.monodon, which accounted for more than 50 % of the production in 1999 (FAO, 2000). In the last few years the whiteleg shrimp, Litopenaeus vannamei, has replaced P.monodon in many countries. Indian shrimp culture is dominated by P.monodon with the East Coast accounting for 70% of the production (Hein, 2002). Intensive culture, apart from other problems, results in enhanced susceptibility of the cultured species to diseases (Jory, 1997), which in fact have become the biggest constraint in shrimp aquaculture (FAO, 2003).
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Kazal-type inhibitors play several important roles in invertebrates, such as anticoagulant, vasodilator and antimicrobial activities. Putative Kazal-type inhibitors were described in several insect transcriptomes. In this paper we characterized for the first time a Kazal unique domain trypsin inhibitor from the Aedes aegypti mosquito. Previously, analyses of sialotranscriptome of A. aegypti showed the potential presence of a Kazal-type serine protease inhibitor, in female salivary glands, carcass and also in whole male, which we named AaTI (A. aegypti trypsin inhibitor). AaTI sequence showed amino acid sequence similarity with insect thrombin inhibitors, serine protease inhibitor from Litopenaeus vannamei hemocytes and tryptase inhibitor from leech Hirudo medicinalis (LDTI). In this work we expressed, purified and characterized the recombinant AaTI (rAaTI). Molecular weight of purified rAaTI was 7 kDa rAaTI presented dissociation constant (K(i)) of 0.15 and 3.8 nM toward trypsin and plasmin, respectively, and it weakly inhibited thrombin amidolytic activity. The rAaTI was also able to prolong prothrombin time, activated partial thromboplastin time and thrombin time. AaTI transcription was confirmed in A. aegypti female salivary gland and gut 3 h and 24 h after blood feeding, suggesting that this molecule can act as anticoagulant during the feeding and digestive processes. Its transcription in larvae and pupae suggested that AaTI may also play other functions during the mosquito`s development. (C) 2010 Elsevier Masson SAS. All rights reserved.
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The integrated culture of seaweed and aquatic animals is an ancient practice in Asian countries. The expansion of this practice to western countries is consequence of the recognition of this system as a sustainable alternative that allows economical diversification and mitigation of environmental impacts generated by effluents of aquaculture. This study evaluated the growth of the seaweed Gracilaria caudata and of the shrimp Litopenaeus vannamei in monoculture (shrimps) and integrated culture (shrimps and algae) systems, and accessed the effect of the seaweed in the water quality. There were two treatments in the experiment: monoculture (shrimps) and integrated culture (shrimps/ algae). The organisms were cultured in 6 aquaria (10L) filled with seawater (35.0±0.0 PSU and 28.1±0.4°C) for 28 days. The nutrients of water (PO43-, NH4+, NO2-, NO3- and DIN), the biomass and the relative growth rate (RGR, % day-1) of seaweed and shrimps were measured weekly. The parameters pH, temperature, salinity and dissolved oxygen were measured daily. The concentration of NH4+ in integrated culture (62.8±25.2µM) was lower (Mann-Whitney p<0.001) than in monoculture (85.6±24.3µM). The mean of PO4- in monoculture (10.4±4.6µM) was markedly higher (Mann-Whitney; p=0.024) than that in integrated culture (8.7±4.1µM). The level of dissolved oxygen in integrated culture (6.0±0.6mg/L) was higher (t-Student; P=0.014) than that in shrimp monoculture (5.8±0.6mg/L). The mean values of the parameters pH, NO2-, NO3- and DIN were 7.5±0.2, 10.1±12.2µM, 24.5±3.2µM and 120.17±30.76µM in monoculture, and 7.5±0.2, 10.5±13.2µM, 27.4±3.5µM and 100.76±49.59µM in integrated culture. There were not differences in these parameters between treatments. The biomass and RGR of seaweed reached 15.0±1.9g and 7.4±2.8% day-1 at the end of the experiment. The performance of shrimp was favorable in monoculture (1.5±0.8g; 5.7±1.6% dia-1) and in integrated culture (1.5±0.7g; 5.2±1.2% dia-1), and the rate of survival was 100% in both treatments. The tolerance and favorable performance of Gracilaria caudata suggest that this seaweed might be integrated into shrimp (Litopenaeus vannamei) culture systems
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This study evaluates the influence of depth and environmental parameters on the development of Gracilaria birdiae Plastino & Oliveira (Gracilariaceae Rhodophyta) in an organic shrimp pound (Litopenaeus vannamei) under euthrophical conditions. PVC structures (module) witch four ropes laden with 150 g of macroalgae each, were kept during 35 days at three different depths (surface, 10 and 20 cm depth). Wet biomass weighing and environmental parameters (temperature, salinity, turbidity, pH, transparence, precipitation, evaporation, insolation, accumulated solar radiation, nitrite, nitrate, ammonium and orthophosphate) were measured weekly. At all three proposed depths, the macroalgae displayed a higher biomass at the end of experiment than at the initial inoculations. The module kept at a 10 cm depth presented the greatest average biomass (186,3), followed by that kept at 20 cm (180,4 g) and the surface module (169,9 g). Biomass variations showed algae to suffer the direct effects of depths. Biomass loss was associated with the factors that influence light penetration, such as sediment deposits above the thallus, rate of evaporation and precipitation. The smallest loses occurred in the algae kept on surface (0,16%), followed by the algae kept at 20 cm (0,20%) and 10 cm (0,22%). The specific growth rate (SGR) of G. birdiae showed no significant difference between the three depths nor the sample periods. Nevertheless, the modules kept at 10 and 20 cm depths presented similar growth evolution, both growing 0,38%·per day-1, while the module kept on surface had an average SGR of 0,36%·day-1. The models related to growth rate demonstrated temperature, salinity, pH, orthophosphate, ammonium, precipitation and turbidity as the principal environmental parameters influencing the development of G. birdiae
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This work aimed to study the structure and dynamic of Phytoplankton and Bacterioplankton in a complete cycle of shrimp cultivation (Litopenaeus vannamei) and determine the environmental factors responsible for the structural changes of these communities. The study was realized in a saltwater shrimp farm (Macaíba, RN), between September/2005 and February/2006, and in a freshwater shrimp farm (Ceará Mirim, RN), between May/2007 and September 2007. The samplings were collected weekly in saltwater farm and every fifteen days in freshwater farm. Total phosphorus, chlorophyll a and environmental parameters (pH, dissolved oxygen, salinity, temperature, depth and water transparency) were measured. Qualitative and quantitative analysis of the phytoplankton and bacterioplankton were carried out. The Shannon-Wiener ecologic indexes of diversity and the Pielou equitability indexes were calculated to the phytoplankton. Bacterial density was determined by epifluorescence microscopy. The data were statistically analyzed by Pearson correlation and t-Test. Chlorophycea were predominat in salt water and in the captation/drainage point (24 to 99%). Diatoms had higher wealth. The species Choricystis minor had the highest occurrence (100%) and dominance (90-100%), thus showing its adaptation to the high temperatures, salinity and low water transparency conditions. Filamentous Cyanobacteria like Oscillatoria sp., Pseudoanabaena sp. and Phormidium sp. had constant levels. The negative correlation between chlorophycea and water transparency, and the positive correlation between chlorophyll a and salinity, showed that the phytoplankton was well adapted to the low transparency and to the high salinity. The bacterioplankton was negatively correlated with the total phosphorus and salinity. In freshwater, Cyanobacteria were predominant (>80%), presenting some producers of toxins species like Microcystis sp., Aphanizomenon sp., Cylindrospermopsis raciborskii e Anabaena circinalis. Cyanobacterial density and total phosphorus and chlorophyll a concentrations exceeded the maximum value allowed by legislation. The means of total phosphorus varied from 264 to 627 Wg.L-1 and the means of chlorophyll a oscillated between 22 and 182 Wg.L-1. The phytoplankton species were selected by low availability of the light, high pH, temperature and high availability of total phosphorus. The bacterioplankton showed high densities (5,13 x 107 to 8,50 x107 Bac.mL-1). The studied environments (ponds and rivers) presented a high level of trophic state based on the high concentrations of chlorophyll a and total phosphorus and cyanobacteria dominance. The composition of species in the ponds and rivers was similar, as well as high concentrations of total phosphorus and chlorophyll a, highlighting the pollution caused by the discharges of the farms in natural environment
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Guaraíras lagoon, located in Tibau do Sul in the eastern littoral of Rio Grande do Norte (Brazil), presents a permanent connection to the sea, which guarantees the occurrence of a rich biodiversity, which includes the autochthonous shrimp species Litopenaeus schmitti, Farfantepenaeus subtilis and Farfantepenaeus brasiliensis. In spite of being subject to a strong human intervention in the last decade, mainly related to the installation of shrimp (Litopenaeus vannamei) farms, the lagoon is still scarcely studied. The present study aims at characterizing the populations of the three autochthonous penaeid shrimp species inhabiting Guaraíras, taking into consideration their abundance and seasonal distribution in the inflow channel of Primar System of Organic Aquaculture (Tibau do Sul, Rio Grande do Norte, Brazil). Twelve monthly samples were carried out from May 2005 to April 2006 with the aid of a circular cast net in the inflow channel, which is daily supplied with water from Guaraíras. Sampling months were grouped in trimesters according to the total pluviosity, thus comprising four trimesters. Water salinity was monitored twice a week and temperature values registered on a daily basis at noon, during the study period. The daily pluviosity data from the municipality of Tibau do Sul were supplied by Empresa de Pesquisa Agropecuária do Rio Grande do Norte (EMPARN). Collected shrimp were identified, weighted, measured and sexed. L. schmitti specimens (0.2 g to 17.8 g) were distributed in 1.3 g weight classes intervals. From the eighth sampling month (December 2005) onwards, males were classified into three categories, in accordance with the development of their petasm: (a) rudimentary petasm, (b) partially formed petasm, and (c) completely formed petasm. Among the ecological variables, rainfall showed the greatest dispersion (s.d.=187.74Rainfall and abundance of L. schmitti were negatively correlated (r = -0.85) whereas its abundance and water salinity were positively correlated (r = 0.63). Among 1,144 collected individuals, 1,127 were L. schmitti, 13 were F. subtilis and 4 were F. brasiliensis, which corresponded to 98.51%, 1.14% and 0.35% of the total of collected individuals. L. schmitti occurred in 100 % of all samples. Differently, the presence of F. subtilis and F. brasiliensis was restricted to 33% and 17% of the collected samples, respectively. The present study confirmed the occurrence of L. schmitti, F. brasiliensis and F. subtilis in Guaraíras. However, this lagoon seems to be primarily inhabited by juvenile Litopenaeus schmitti. The population of L. schmitti analysed showed a seasonal pattern of distribution. In general, in the months of high salinity and absence of rain, the number of individuals was higher than in the wet months. Further studies on the reproductive biology and ecology of L. schmitti, F. brasiliensis and F. subtilis may elucidate questions referring to the abundance, period, and phase of occurrence of these shrimp genera in Guaraíras. Finally, the risks associated to the establishment of L. vannamei in the lagoon provide a novel outlet for studies in this biotope
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The incidence of toxic cyanobacterial blooms is one of the important consequences of eutrophication in aquatic ecosystems. It is a very common phenomenon in reservoirs and shrimp ponds in the State of Rio Grande do Norte (RN), Brazil. Cyanobacterias produce toxins which can affect aquatic organisms and men trough the food chain. Aiming to contribute to the studies of cyanobacterias in RN, we propose: a) to evaluate the toxicity of isolated cyanobacterias in important fresh-water environments; and b) to verify the effects of both natural and cultured blooms occurred in reservoirs for human supply and in the cladoceran Ceriodaphnia silvestrii. This study was carried out using samples of natural blooms occurred between March and October of 2004 in Gargalheiras Dam (08º L e 39º W), in July of 2004 in Armando Ribeiro Gonçalves Dam (06o S e 37o W) and in commercial shrimp ponds (Litopenaeus vannamei) located in fresh-water environments. The samples were collected with plankton net (20µm.) for identification, isolation and obtaining of phytoplanktonic biomass for liophilization and later toxicity bioassays. The toxicity of cultured samples and natural blooms was investigated through bioassays in Swiss mice. Quantification of cyanobacteria in samples was conducted following the Ütermol method, with 300mL samples fixed with lugol. The toxicity test with Ceriodaphnia silvestrii followed ABNT, 2001 recommendations, and were accomplished with natural hepatotoxic bloom s samples and cultured samples of both non-toxic and neurotoxic C. raciborskii. In this test, five newborns, aged between 6 and 24 hours, were exposed to different concentrations (0 a 800 mg.L-1) of crude cyanobacterial extracts during 24 and 48 hours. Three replicates were used per treatment. The pH, temperature and dissolved oxygen at the beginning and after 24 and 48hours from the test were measured. We estimated the CL50 through the Trimmed Spearman-Karber method. The blooms were constituted by Microcystis panniformis, M. aeruginosa, Anabaena circinalis, Cylindrospermopsis raciborskii and Planktothrix agardhii, producers of mycrocistin-LR confirmed with HPLC analysis. Samples of hepatotoxic blooms registered toxinogenic potential for C. silvestrii, with CL50-24h value of 47.48 mg.L-1 and CL5048h of 38.15 mg.L-1 for GARG samples in march/2005; CL50-24h of 113,13 mg.L-1 and CL5048h of 88,24 mg.L-1 for ARG July/2004; CL50-24h of 300.39 mg.L-1 and CL50-48h of 149.89 mg.L-1 for GARG October/2005. For cultured samples, values of CL50-24h and CL50-48h for C. raciborskii toxic strains were 228.05 and 120.28 mg.L-1, respectively. There was no mortality of C. silvestrii during the tests with non-toxic C. raciborskii strain. The toxicity test with C. silvestrii presented good sensitivity degree to cyanotoxins. The toxicity of natural hepatotoxic blooms samples (microcystins) and cultured neurotoxic saxitoxins producer samples analyzed in this study give us strong indications of that toxin s influence on the zooplanktonic community structure in tropical aquatic environments. Eleven cyanobacteria strains were isolated, representing 6 species: Anabaenopsis sp., Cylindrospermopsis raciborskii, Chroococcus sp., Microcystis panniformis, Geitlerinema unigranulatum e Planktothrix agardhii. None presented toxicity in Swiss mice. The strains were catalogued and deposited in the Laboratório de Ecologia e Toxicologia de Organismos Aquáticos (LETMA), in UFRN, and will be utilized in ecotoxicológical and ecophysiological studies, aiming to clarify the causes and control of cyanobacterial blooms in aquatic environments in RN. This state s reservoirs must receive broader attention from the authorities, considering the constant blooms occurring in waters used for human consumption
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The objective of this study was to examine the growth of Gracilaria cervicornis cultured in a shrimp (Litopenaeus vannamei) pond and to determine the absorption efficiency and the kinetics parameters (Vmax, Ks e Vmax:Ks) of this macroalgae for the nutrients N-NO3-, N-NH4+ and P-PO4-3, aiming at its use as bioremediatory of eutrophicated environments. For this study, two experiments (field and laboratory) were developed. In the field study, the seaweed was examined in relation to the growth and the biomass. In the laboratory experiment, the absorption efficiency of G. cervicornis was measured through the monitoring of the concentration of the three nutrients (N-NO3-, N-NH4+ e P-PO4-3) during 5 hours and the kinetic parameters were determined through the formula of Michaelis-Menten. The results obtained in this study demonstrated that G. cervicornis benefited from the available nutrients in the pond, increasing 52.4% of its biomass value after 30 days of culture. It was evidenced that the variability of the biomass could be explained through the salinity, availability of light (transparency and solid particle in suspension) and concentration of N-NO3- in the environment. In the laboratory experiment, the highest absorption efficiency was found in the treatments with low concentration (5 µmol.L-1), being evidenced a reduction of up to 85,3%, 97,5% and 81,2% of N-NH4+, N-NO3- and P-PO43-, respectively. Regarding the kinetic parameters, G. cervicornis presented better ability in absorbing N-NH4+ in high concentrations (Vmax = 158,5 µmol g-1 dry wt h-1) and P-PO43- in low concentrations (Ks = 5 µmol.L-1 e Vmax:Ks = 10,3). The results of this study show that G. cervicornis could be cultivated in shrimp ponds, presents a good capacity of absorption for the tested nutrients and is a promising candidate for biorremediation in shrimp pond effluent
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In recent years, sulfated polysaccharides from marine algae have emerged as an important class of natural biopolymers with potential application in human and veterinary health care, while taking advantage of the absence of potential risk of contamination by animal viruses. Among these, fucans isolated from the cell walls of marine brown alga have been study due to their anticoagulant, antithrombotic, anti-inflammatory and antiviral activities. These biological effects of fucans have been found to depend on the degree of sulfation and molecular size of the polysaccharide chains. In the present study, we examined structural features of a fucan extracted from brown alga Dictyota menstrualis and its effect on the leukocyte migration to the peritoneum. The sulfated polysaccharides were extracted from the brown seaweed by proteolytic digestion, followed by sequential acetone precipitation producing 5 fractions. Gel lectrophoresis using 0.05 M 1,3-diaminopropane-acetate buffer, pH 9.0, stained with 0.1% toluidine blue, showed the presence of sulfated polysaccharides in all fractions. The chemical analyses demonstrated that all fractions are composed mainly of fucose, xylose, galactose, uronic acid, and sulfate. Electrophoresis in agarose gel in three different buffers demonstrated that the fraction 2.0v have only one population of fucan. This compound was purify by exclusion molecular. It has shown composition of fucose, xilose, sulfate and uronic acid in molar ration of 1.0: 1.7: 1.1: 0.5 respectively. The effect of this heterofucan on the leukocyte migration was observed 6h after zymozan (mg/g) administration into the peritoneum. The heterofucan showed higher antimigratory activity, it decrease the migration of leukocyte in 83.77% to peritoneum. The results suggest that this fucan is a new antimigratory compound with potential pharmacological appications
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The acidic galactan (AG) was obtained by extraction and proteolysis by acetone precipitation of the eggs of the mollusc Pomacea lineata. Its structure was elucidated by a combination of chemical analysis, the intrinsic viscosity and NMR spectroscopy 1D and 2D. Biological aspects of AG were evaluated by in vivo testing of healing and peritonitis induced (anti-inflammatory activity) and in vitro assays of cytotoxicity (MTT). This polymer showed a simple structure without the presence of sulfate and uronic acids in its structure. Its intrinsic viscosity and relative were evaluated at 0.44 ± 0.05 and 1.744± 0.07 dl.g-1. Spectroscopy showed that the AG has a constitution composed predominantly of β-D-galactosis, and β-D-glucosamine-NAcetil that comes in a smaller proportion in chain. The character of this acidic polysaccharide is given by the presence of pyruvate in the molecule, forming a cyclic acetal of six states, located in β-D-galactosis. The involvement of AG in the healing process was evaluated and the histological analysis revealed that there was so early in the process of healing, a great stimulation of macrophages with granuloma formation. Suggesting that AG may have promoted the advance of biological events required for tissue healing. In the trial of the GA-induced peritonitis showed dose dependent, demonstrating the anti-inflammatory effect at concentrations above 20 mg/kg, and confirming its inflammatory character and the concentration of 1mg/kg. In vitro tests used in the GA concentration of 1000 μg/mL showed proliferative activity by stimulating the growth of 3T3 cells, corroborating the findings in vivo and demonstrating the absence of cytotoxic activity
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Chitin and chitosan are nontoxic, biodegradable and biocompatible polymers produced by renewable natural sources with applications in diverse areas such as: agriculture, textile, pharmaceutical, cosmetics and biomaterials, such as gels, films and other polymeric membranes. Both have attracted greater interest of scientists and researchers as functional polymeric materials. In this context, the objective of this study was to take advantage of the waste of shrimp (Litopenaeus vannamei and Aristeus antennatus) and crabs (Ucides cordatus) from fairs, beach huts and restaurant in Natal/RN for the extraction of chitin and chitosan for the production of membranes by electrospinning process. The extraction was made through demineralization, deproteinization, deodorization and deacetylation. Morphological analyzes (SEM and XRD), Thermal analysis (TG and DTG), Spectroscopy in the Region of the Infrared with Transformed of Fourier (FTIR) analysis Calorimetry Differential Scanning (DSC) and mechanical tests for traction were performed. In (XRD) the semicrystalline structure of chitosan can be verified while the chitin had higher crystallinity. In the thermal analysis showed a dehydration process followed by decomposition, with similar behavior of carbonized material. Chitosan showed temperature of maximum degradation lower than chitin. In the analysis by Differential Scanning Calorimetry (DSC) the curves were coherent to the thermal events of the chitosan membranes. The results obtained with (DD) for chitosan extracted from Litopenaeus vannamei and Aristeus antennatus shrimp were (80.36 and 71.00%) and Ucides cordatus crabs was 74.65%. It can be observed that, with 70:30 solutions (v/v) (TFA/DCM), 60 and 90% CH3COOH, occurred better facilitate the formation of membranes, while 100:00 (v/v) (TFA/DCM) had formation of agglomerates. In relation to the monofilaments diameters of the chitosan membranes, it was noted that the capillary-collector distance of 10 cm and tensions of 25 and 30 kV contributed to the reduction of the diameters of membranes. It was found that the Young s modulus decreases with increasing concentration of chitosan in the membranes. 90% CH3COOH contributed to the increase in the deformation resulting in more flexible material. The membranes with 5% chitosan 70:30 (v/v) (TFA/DCM) had higher tensile strength
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In this study, we worked with the validation of a methodology for analysis of bioactive amines in shrimp, considering it to be one of the main products of the northriograndense trade balance, maintaining the state of Rio Grande do Norte topped the list of Brazilian exports of this product the last decade. The sector of the Brazilian shrimp works exclusively with gray shrimp Litopenaeus Vannamei since the late 1990s. This study used liquid chromatography with conductimetric detector, using as the mobile phase methylsulfonic 3 mM acid (MSA) with gradient and phase C18 column with reverse the development of methodology for the analysis of bioactive amines in shrimp. In the sample preparation was used as 5% trichloroacetic acid (TCA) extraction solution. Validation analysis of biotativas amines (putrescine - PUT, histamine - HIST, agmatine - AGM, spermidine - EPD and spermine - EPN) in shrimp, the linear working range was 0.1 to 2.0 mg L-1 to was sensitive, homoscedastic, in effect, selective, accurate and precise array. Thus, considered feasible for these determinations bioactive amines in this array. Determined the concentration of these amines in fresh shrimps (AGM = 0.61 ± 0.05 mg kg- 1 EPD = 2.57 ± 0.14 mg kg-1 and EPN = 1.79 ± 0.11 mg kg-1), and freezing weather predetermined in cooked shrimp (AGM = 6.28 ± 0.18 mg kg-1, EPD = 12.72 ± 0.02 mg kg- 1 and EPN = 22.30 ± 0.60 mg kg-1), the shrimp with twenty-four hour stay at room temperature (PUT = 879.52 ± 28.12 mg kg-1, AGM = 848.13 ± 19.40 mg kg-1, ESPD = 13.59 ± 0.97 mg kg-1 and ESPN = 18.47 + 1.57 mg kg-1). In shrimp subjected to freezing for a week, two weeks, three weeks and four weeks, the results showed that there is an increase in the content of agmatine (7.31 ± 0.21 mg kg-1) while in spermine ( 1.22 ± 0.14 mg kg-1) and spermidine (below limit of quantification) there was a decrease in the freeze time, while there is a decrease in the level of spermidine not reaching detectad. The putrescine was only found in shrimp that remained for 24 hours at room temperature and histamine was not found in any of the samples
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Marine biological invasions have been regarded as one of the major causes of native biodiversity loss, with shipping and aquaculture being the leading contributors for the introductions of alien species in aquatic ecosystems. In the present study, five aquatic alien species (one mollusk, three crustaceans and one fish species) were detected during dives, shore searches and from the fisheries on the coast of the Delta do Parnaiba Environmental Protection Area, in the States of Piaui and Maranhao, Northeastern Brazil. The species were the bicolor purse-oyster Isognomon bicolor, the whiteleg shrimp Litopenaeus vannamei, the giant river prawn Macrobrachium rosenbergii, the Indo-Pacific swimming crab Charybdis hellerii and, the muzzled blenny Omobranchus punctatus. Ballast water (I. bicolor, C. hellerii, and O. punctatus) and aquaculture activities (L. vannamei and M. rosenbergii) in adjacent areas are the most likely vectors of introduction. All exotic species found have potential impact risks to the environment because they are able to compete against native species for resources (food and habitat). Isognomon bicolor share the same habitat and food items with the native bivalve species of mussels and barnacles. Litopenaeus vannamei share the same habitat and food items with the native penaeids such as the pinkspot shrimp Farfantepenaeus brasiliensis, the Southern brown shrimp Farfantepenaeus subtilis, and the Southern white shrimp Litopenaeus schmitti, and in the past few years L. vannamei was responsible for a viral epidemics in the cultivation tanks that could be transmitted to native penaeid shrimps. Charybdis hellerii is also able to cause impacts on the local fisheries as the species can decrease the populations of native portunid crabs which are commercialized in the studied region. Macrobrachium rosenbergii may be sharing natural resources with the Amazon River prawn Macrobrachium amazonicum. Omobranchus punctatus shares habit with the native redlip blenny Ophioblennius atlanticus and other fishes, such as the frillfin goby Bathigobius soporator. Some immediate remedial measures to prevent further introductions from ballast water and shrimp farm ponds should be: (i) to prevent the release of ballast water by ship/vessels in the region; (ii) to reroute all effluent waters from shrimp rearing facilities through an underground or above-ground dry well; (iii) to install adequate sand and gravel filter which will allow passage of water but not livestock; (iv) outdoor shrimp pounds located on floodable land should be diked, and; (v) to promote environmental awareness of those directly involved with ballast water (crews of ship/vessels) and shrimp farms in the region. Rev. Biol. Trop. 58 (3): 909-923. Epub 2010 September 01.