Potential respiration is a better respiratory predictor than biomass in young Artemia salina

[EN] These experiments test whether respiration can be predicted better from biomass or from potential respiration, a measurement of the mitochondrial and microsomal respiratory electron transport systems. For nearly a century Kleiber's law or a similar precursor have argued the importance of biomass in predicting respiration. In the last decade, a version of the Metabolic Theory of Ecology has elaborated on Kleiber's Law adding emphasis to the importance of biomass in predicting respiration. We argue that Kleiber's law works because biomass packages mitochondria and microsomal electron transport complexes. On a scale of five orders of magnitude we have shown previously that potential respiration predicts respiration aswell as biomass inmarine zooplankton. Here, using cultures of the branchiopod, Artemia salina and on a scale of less than 2 orders of magnitude,we investigated the power of biomass and potential respiration in predicting respiration.We measured biomass, respiration and potential respiration in Artemia grown in different ways and found that potential respiration (Ф) could predict respiration (R), both in μlO2h−1 (R=0.924Φ+0.062, r2=0.976), but biomass (as mg dry mass) could not (R=27.02DM+8.857, r2=0.128). Furthermore the R/Ф ratio appeared independent of age and differences in the food source.

Physiological and metabolic effects of nutrient enrichment on adult Artemia franciscana

[EN] Brine shrimp nauplii (Artemia sp.) are used in aquaculture as the major food source for many cultured marine larvae, and also used in the adult phase for many juvenile and adult fish. One artemia species, Artemia franciscana is most commonly preferred, due to the availability of its cysts and to its ease in hatching and biomass production. The problem with A. franciscana is that its nutritional quality is relatively poor in essential fatty acids, so that it is common practice to enrich it with emulsions like SELCO and ORIGO. This “bioencapsulation”, enrichment method permits the incorporation of different kinds of products into the artemia. This brine-shrimp’s non-selective particle-feeding habits, makes it particularly suitable for this enrichment process. The bioencapsulation is done just prior to feeding the artemia to a predator organism. This allows the delivery of different substances, not only for nutrient enrichment, but also for changing pigmentation and administering medicine. This is especially useful in culturing ornamental seahorses and tropical fish in marine aquaria In this study the objectives were to determine, the relative nutrient value of ORIGO and SELCO as well as the optimal exposure to these supplements prior to their use as food-organisms.

The effects of supplementation of decapod zoea to Artemia basal diet on the digestive gland histology and the fatty acid composition in common octopus (Octopus vulgaris) paralarvae.

[EN]The present study aimed to evaluate the effect of the supplementation of different crab zoeas to enriched Artemia basal diet for O. vulgaris paralarvae during the first month of life. Paralarvae were fed using: enriched Artemia nauplii alone and Artemia co-fed with either first zoea stages of Grapsus adscensionis or Plagusia depressa. The experiment was carried out over a period of 28 days, in 0.12 m3 tanks with a flow-through rearing system. Growth in dry weightas well as mantle length and width were assessed weekly. Additionally, prey and paralarvae fatty acid composition and digestive gland (DG) histology were evaluated.

Utilização de embriões liofilizados e flocos de Artemia na diversificação nutricional de pós-larvas do camarão marinho Litopenaes vannamei (Boone, 1931)

The objective of the current study was to evaluate the zootechnical performance (survival and growth) of Litopenaeus vannamei post-Iarvae fed an artificial shrimp diet supplemented with Artemia flakes or freeze-dried Artemia embryos. For that purpose, 20 culturing units were individually stocked with 50 shrimp post-Iarvae (average dry weight of 0,3 ± 0,03 mg) at a stocking density of 20 post-larvae per liter, and fed the experimental diets to satiation during 20 days. The experimental design consisted of four diets (T1, T2, T3 and T4) with five repetitions each. For treatments T1, T2 and T3, dietary supplements of 5mg of Artemia flakes (T1), freeze-dried Artemia embryos (T2), and of the commercial shrimp diet (T3) were offered 2 hours after the shrimp were initially fed the commercial shrimp diet. For treatment T4 (control), no additive was offered 2 hours after the initial feeding. Shrimp survival, absolut (GPA) and relative increase in weight (GPR), and specific growth rate (TCR) were used as evaluation criteria. After the experimental period, no significant statistical differences (p>0,05) in survival were observed. Regarding growth, the dietary treatment which used freeze-dried Artemia embryos as an additive (T2) presented the best results for GPA (6,7 ± 0,7 mg). There were no statistical differences within treatments T1, T3 and T4 (p>0,05). AIso, post-larvae fed freeze-dried embryos (T2) showed a relative increase in weight (2241,4%) which differed significantly (p<0,05) from T4(1911,7%) but not from T1 (1801,6%) or T3 (1946,7%). In conclusion, the results of the current study indicate that an artificial shrimp diet supplemented with freeze-dried Artemia embryos fulfils the nutritional requirements of post-larvae L. vannamei and promotes a better growth than diets not supplemented with Artemia flakes

Purificação e caracterização parcial de uma B-D glicosidase de Artemia franciscana com ação sobre celobiose e lactose

-D-glucosidase (EC 3.2.1.21) is one of the most interesting glycosidases, especially for hydrolysis cellobiose releasing glucose, is last step degradation of cellulose. This function makes the -D-glucosidase is of great interest as a versatile industrial biocatalyst, being critical to various bio-treatment / biorefinery processes, such as bioethanol production. Hen in the report, a -D-glucosidase was extracts from protein extracted of the invertebrate marine Artemia franciscana was purified and characterized with a combination of precipitation with ammonium sulfate (0 - 30%, 30 to 50%, 50 to 80%), the fraction saturated in the range of 30 to 50% (called F-II) was applied in a molecular exclusion chromatography, in Sephacryl S-200, the fractions corresponding to the first peak of activity of -D-glucosidase were gathered and applied in a chromatography of ion exchange in Mono Q; the third peak this protein obtained chromatography, which coincides with the peak of activity of -D-glucosidase was held and applied in a gel filtration chromatography Superose 12 where the first peak protein, which has activity of -D-glucosidase was rechromatography on Superose 12. This enzyme is probably multimerica, consisting of three subunit molecular mass of 52.7 kDa (determined by SDS-PAGE) with native molecular mass of 157 kDa (determined by gel filtration chromatography on Superose 12 under the system FPLC). The enzyme was purified 44.09 times with a recovery of 1.01%. Using up p-nitrophenyl-β-D-glucopiranoside as substrate obtained a Km apparent of 0.229 mM and a Vmax of 1.109 mM.60min-1.mL-1mM. The optimum pH and optimum temperature of catalysis of the synthetic substrate were 5.0 and 45 °C, respectively. The activity of the -D-glucosidase was strongly, inhibited by silver nitrate and N- etylmaleimide, this inhibition indicates the involvement of radical sulfidrila the hydrolysis of synthetic substrate. The -D-glucosidase of Artemia franciscana presented degradativa action on celobiose, lactose and on the synthetic substrate -nitrophenyl-β-D-glucopiranoside indicating potential use of this enzyme in the industry mainly for the production of bioethanol (production of alcohol from the participating cellulose), and production hydrolysate milk (devoid of milk lactose)

Atividade β-D-N-Acetilglucosaminidásica de enzimas imobilizadas extraídas da Artemia franciscana e possíveis aplicações biotecnológicas

A β-D-N-acetilglucosaminidase extracted and partially isolated from crustacean Artemia franciscana by ammonium sulfate precipitation and filtration gel chromatography Bio Gel A 1.5m. the enzyme was immobilized on ferromagnetic Dacron yielding a insoluble active derivative with 5.0 units/mg protein and 10.35% of the soluble enzyme activity. β-D-N-acetilglucosaminidase-ferromagnetic Dacron was easily removed from the reaction mixture by a magnetic field, it was reused for ten times without loss in its activity. The ferromagnetic Dacron was better activated at pH 5.0. The particles visualized at scanning electron microscope (SEM) had presented different sizes, varying between 721nm and 100µm. Infra red confirmed immobilization on support, as showed by primary amino peaks at 1640 and 1560 cm-1 . The immobilize enzyme presented Km of 2.32 ± 0.48 mM and optimum temperature of 50°C. Bought presented the same thermal stable of the soluble enzyme and larger enzymatic activity at pH 5.5. β-D-N-acetilglucosaminidase-Dacron ferromagnético showed sensible for some íons as the silver (AgNO3), with loss of activity. The β-D-N acetilglucosaminidase activity for mercury chloride (HgCl2), whom is one of the most toxic substance joined in nature, it was presented activity already diminished at 0,01mM and lost total activity at 4mM, indicating sensitivity for this type of metal. β-D-N-acetilglucosaminidase-ferromagnetic Dacron showed degradative capacity on heparan sulfate, the enzyme still demonstrated degradative capacity on heparan sulphate, suggesting a possible application to produce fractions of this glycosaminoglycan

Avaliação do potencial anti-inflamatório, anticoagulante e hemorrágico de heparinóides presentes em "Artemia franciscana"

Heparan sulfate (HS) and Heparin (Hep) glycosaminoglycans (GAGs) are heterogeneous and highly charged polysaccharides. HS is structurally related to Hep but is much less substituted with sulfo groups than heparin and has a more varied structure (or sequence). Because of structural similiarities between these two polymers, they have been described together as heparinoids . Both chains bind a variety of proteins and mediate various physiologically important processes including, blood coagulation, cell adhesion and growth factor regulation. Heparinoids with structural characteristics similar to these described from HS and/or Hep from mammalian tissues have been isolated from different species of invertebrates, although only a few heparinoids from unusual sources have been characterized. The present study describes the presence of unusual heparinoids population from Artemia franciscana, isolated after proteolysis and fractionation by ion exchange resin and named, F-3.0M. The study model in vivo were hemostasis (rat tail scarification) and inflamatoty activity. The tests in vitro were used for coagulations assays (PT and APTT). The analyse of the heparinoids eluted with 3,0M NaCl showed electrophoretic migration in different buffer systems a single band with a behaviour intermediate between those of mammalian HEP and HS. The main products obtained from Artemia heparinoids after enzymatic degradation with heparitinases I and II from F. heparinum were N-sulphated disaccharides (∆U-GlcNS,6S/ ∆U,2S-GlcNS and ∆U-GlcNS) and N-acetylated disaccharides (∆U, GlcNAc). This heparinoid had a lower hemorrhagic effect (400μg/ml) when compared to unfractiionated heparins(25μg/ml).The results also suggest a negligible APTT activity of this heparinoid (62.2s). No action was observed on PT indicating that F-3.0M haven t action on the extrinsic pathway. The results showed that the fraction F- 3.0M have inhibitory effect on migration of leukocytes, 64.5% in the concentration of 10 μg/ml (P<0.001). The search for new heparin and/or heparan sulphates analogs devoid of anticoagulant activity is an atractive alternative and may open up a wide variety of new therapeutic applications

Avaliação da toxicidade do mangue de Bertioga, Cubatão-SP, em decorrência de derramamento de óleo, utilizando o microcrustáceo Artemia salina como bioindicador.

Sedimentos de mangue contaminados ou não com produtos derivados do petróleo foram avaliados quanto à sua toxicidade. De todos os parâmetros que determinam qualidade do solo, os testes toxicológicos usando microcrustáceos vivos como bioindicador são os mais adequados em virtude de suas sensibilidades a componentes químicos e tóxicos do ambiente. Para que estratégias de recuperação de áreas degradadas sejam adotadas é importante que se conheça a extensão dos distúrbios provocados no ecossistema através desses testes. Os maiores valores de mortalidade foram encontrados nas áreas contaminadas, no ponto de transição, utilizando 100g de sedimento. No mangue não contaminado com óleo não houve mortalidade em nenhuma das áreas, independentemente dos métodos utilizados.