658 resultados para PENAEUS-JAPONICUS


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Aspergillus phoenicis biofilms on polyethylene as inert support were used to produce fructooligosaccharides (FOS) in media containing 25% (m/V) of sucrose as a carbon source. The maximum production of total FOS (122 mg/mL), with 68% of 1-kestose and 32% of nystose, was obtained in Khanna medium maintained at 30 degrees C for 48 h under orbital agitation (100 rpm). At high concentrations of sucrose (30%, m/V), the recovery of FOS was higher than that observed at a low concentration (5%, m/V). High levels of FOS (242 mg/mL) were also recovered when using the biofilm in sodium acetate buffer with high sucrose concentration (50%, m/V) for 10 h. When the dried biofilm was reused in a fresh culture medium, there was a recovery of approx. 13.7% of total FOS after 72 h of cultivation at 30 C, and 10% corresponded to 1-kestose. The biofilm morphology, analyzed by scanning electron microscope, revealed a noncompact mycelium structure, with unfilled spaces and channels present among the hyphae. The results obtained in this study show that A. phoenicis biofilms may find application for FOS production in a single-step fermentation process, which is cost-effective in terms of reusability, downstream processing and efficiency.

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BACKGROUND: Cellulose and hemicellulose are quantitatively the most important structural carbohydrates present in ruminant diets. Rumen micro-organisms produce enzymes that catalyse their hydrolysis, but the complex network formed by structural carbohydrates and lignin reduces their digestibility and restricts efficient utilisation of feeds by ruminants. This study aimed to produce two enzymatic extracts, apply them in ruminant diets to determine the best levels for ruminal digestibility and evaluate their effects on in vitro digestibility. RESULTS: In experiment 1 a two-stage in vitro technique was used to examine the effects of different enzymatic levels of Aspergillus japonicus and Aspergillus terricola on tropical forages. Enzyme addition had minor effects on corn silage at the highest enzymatic level. In experiment 2 an in vitro gas production (GP) technique was applied to determine apparent in vitro organic matter digestibility and metabolisable energy. The addition of enzymes in GP showed interesting results. Good data were obtained using sugar cane and Tifton-85 hay supplemented with extracts of A. japonicus and A. terricola respectively. CONCLUSION: Overall, the study suggests that addition of crude extracts containing exogenous fibrolytic enzymes to ruminant diets enhances the effective utilisation of ruminant feedstuffs such as forages. Copyright (c) 2012 Society of Chemical Industry

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[ES]Durante la campaña La Bocaina 0497 se llevaron a cabo una serie de 14 lances con una red de arrastre pelágico de tipo comercial entre 20 y 700 m. de profundidad y una porspección acústica con una ecosonda SIMRAD EK-500 en aguas neríticas y oceánicas adyacentes a Lanzarote, Fuerteventura y Gran Canaria. Además se obtuvieron imágenes SST para obtener información de las condiciones hidrológicas en el área de estudio. Los resultados mostraron que la caballa Scomber japonicus presentaba gran variabilidad espacial en biomasa entre las diferentes localidades muestreadas.

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Questa tesi è dedicata alla qualità dell'alimento ittico in tre delle sue possibili accezioni. Dopo aver spiegato il complicato rapporto del consumatore con gli alimenti ittici e come l'Unione Europea abbia cercato di fare chiarezza al riguardo, gli argomenti di discussione saranno: Autenticazione d'origine La polpa di 160 esemplari di spigola (Dicentrachus labrax), suddivisi tra selvatici, allevati intensivamente e allevati estensivamente, provenienti dall'Italia e dall'estero per un totale di 18 fonti indagate, è stati analizzata individualmente per caratterizzarne la componente lipidica, isotopica e minerale e verificare le potenzialità di queste informazioni ai fini della autenticazione di origine in senso lato. Stima della Freshness Quality Numerosi lotti di seppia (Sepia officinalis), nasello (Merluccius merluccius) e triglia di fango (Mullus barbatus) sono stati sottoposti a due possibili modalità di stoccaggio sotto ghiaccio fondente, per indagare come, nell’arco della loro vita commerciale, ne evolvessero importanti connotati chimici (cataboliti dell’ATP e loro rapporti), fisici (proprietà dielettriche dei tessuti) e sensoriali (Quality Index Methods specie-specifici. Studio del profilo nutrizionale La componente lipidica di numerosi lotti di mazzancolla (Penaeus kerathurus), canocchia (Squilla mantis) e seppia (Sepia officinalis) è stata caratterizzata allo stato crudo e dopo cottura secondo tecniche “dedicate” per stabilire il contributo di queste matrici come fonte di acidi grassi polinsaturi della serie omega 3 e per pervenire alla determinazione dei loro coefficienti di ritenzione vera.

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The spatio-temporal distribution of megistobenthic crustacean assemblages from the Antalya Gulf, located in the Levantine Sea is described. In order to provide a comprehensive overview of the spatio-temporal patterns of the crustacean community, 3 transect including depth of 10, 25, 75, 125 and 200 m, were studied between 2014 and 2015 to investigate their association with a set of environmental parameters in representative months of each season (spring, summer, autumn and winter). For its economic importance in Levantine waters, a focus analysis of deep-water rose shrimp Parapenaeus longirostris (Lucas, 1846) was done, to investigate the length frequency composition of the population of the Antalya Gulf. A total of 58 crustacean species were encountered in the study area, of these species identified, 18 species were recognized as alien species in the Mediterranean Sea. Throughout the year the most frequent species of the study were the hermit crab Pagurus prideaux (Leach, 1815) and Parapenaeus longirostris (Lucas, 1846) followed by the Indo-Pacific swimming crab Charybdis longicollis (Leene, 1938) and by the invasive shrimp Marsupenaeus japonicus (Spence Bate, 1888). Few species contributing to a high amount to the total biomass were found throughout the year. These species were Charybdis longicollis and Parapenaeus longirostris. Stations of the study area showed similar values of diversity indices of benthic crustacean community among the three transect. The highest values of faunistic indices were detected in autumn and winter (October and February), and also varied along the depth gradient, with the highest values found between 25 and 75 meters. The multivariate analyses conducted on the abundance data point out major differences between depths and between seasons. Therefore, according to cluster analysis and ordination over abundance and biomass, three main crustacean assemblages were detected: the first corresponding to shallow bottoms (10, 25 meters), the second corresponding to intermediate waters (75 meters) and the last to deeper waters (125, 200 meters). Depth was the main factor governing the distribution of megistobenthic crustacean in the area. Besides the depth, the structure of the sediment is the most important factor in determining the crustacean assemblage. Therefore, all factors governing the crustacean distribution were found to be related to the bottom depth. The population of Parapenaeus longirostris in the Antalya Gulf showed significant differences in depth. It was found that females dominated the population of the study area (65.11%), and were significantly larger than males for each cohort identified. The size-weight relationships revealed a slight negative allometry in growth, a bit more pronounced in females than in males.

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Gregarine apicomplexans are a diverse group of single-celled parasites that have feeding stages (trophozoites) and gamonts that generally inhabit the extracellular spaces of invertebrate hosts living in marine, freshwater, and terrestrial environments. Inferences about the evolutionary morphology of gregarine apicomplexans are being incrementally refined by molecular phylogenetic data, which suggest that several traits associated with the feeding cells of gregarines arose by convergent evolution. The study reported here supports these inferences by showing how molecular data reveals traits that are phylogenetically misleading within the context of comparative morphology alone. We examined the ultrastructure and molecular phylogenetic positions of two gregarine species isolated from the spaghetti worm Thelepus japonicus: Selenidium terebellae Ray 1930 and S. melongena n. sp. The ultrastructural traits of S. terebellae were very similar to other species of Selenidium sensu stricto, such as having vermiform trophozoites with an apical complex, few epicytic folds, and a dense array of microtubules underlying the trilayered pellicle. By contrast, S. melongena n. sp. lacked a comparably discrete assembly of subpellicular microtubules, instead employing a system of fibrils beneath the cell surface that supported a relatively dense array of helically arranged epicytic folds. Molecular phylogenetic analyses of small subunit rDNA sequences derived from single-cell PCR unexpectedly demonstrated that these two gregarines are close sister species. The ultrastructural differences between these two species were consistent with the fact that S. terebellae infects the inner lining of the host intestines, and S. melongena n. sp. primarily inhabits the coelom, infecting the outside wall of the host intestine. Altogether, these data demonstrate a compelling case of niche partitioning and associated morphological divergence in marine gregarine apicomplexans. (C) 2014 Elsevier GmbH. All rights reserved.

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We have recently shown that the majority of allergens can be represented by allergen motifs. This observation prompted us to experimentally investigate the synthesized peptides corresponding to the in silico motifs with regard to potential IgE binding and cross-reactions with allergens. Two motifs were selected as examples to conduct in vitro studies. From the first motif, derived from allergenic MnSOD sequences, the motif stretch of the allergen Asp f 6 was selected and synthesized as a peptide (MnSOD Mot). The corresponding full-length MnSOD was also expressed in Escherichia coli and both were compared for IgE reactivity with sera of patients reacting to the MnSOD of Aspergillus fumigatus or Malassezia sympodialis. For the second motif, the invertebrate tropomyosin sequences were aligned and a motif consensus sequence was expressed as a recombinant protein (Trop Mot). The IgE reactivity of Trop Mot was analyzed in ELISA and compared to that of recombinant tropomyosin from the shrimp Penaeus aztecus (rPen a 1) in ImmunoCAP. MnSOD Mot was weakly recognized by some of the tested sera, suggesting that the IgE binding epitopes of a multimeric globular protein such as MnSOD cannot be fully represented by a motif peptide. In contrast, the motif Trop Mot showed the same IgE reactivity as shrimp full-length tropomyosin, indicating that the major allergenic reactivity of a repetitive structure such as tropomyosin can be covered by a motif peptide. Our results suggest that the motif-generating algorithm may be used for identifying major IgE binding structures of coiled-coil proteins.

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Scuticociliatosis is an economically important, frequently fatal disease of marine fish in aquaculture, caused by histophagous ciliated protozoa in the subclass Scuticociliatida of the phylum Ciliophora. A rapidly lethal systemic scuticociliate infection is described that affected aquarium-captive zebra sharks (Stegostoma fasciatum), Port Jackson sharks (Heterodontus portusjacksoni), and a Japanese horn shark (Heterodontus japonicus). Animals died unexpectedly or after a brief period of lethargy or behavioral abnormality. Gross findings included necrohemorrhagic hepatitis and increased volumes of celomic fluid. Histologically, 1 or more of a triad of necrotizing hepatitis, necrotizing meningoencephalitis, and thrombosing branchitis were seen in all cases, with necrotizing vasculitis or intravascular fibrinocellular thrombi. Lesions contained variably abundant invading ciliated protozoa. Molecular identification by polymerase chain reaction from formalin-fixed tissues identified these as the scuticociliate Philasterides dicentrarchi (syn. Miamiensis avidus), a novel and potentially emergent pathogen in sharks.

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An experiment was carried out on the soft bottom in the sublitoral zone of the Furugelm Island (Peter the Great Bay, Sea of Japan) to study formation of benthic communities. Boxes with defauned sediments were placed on depths of 4, 6 and 13 m and exposed during 60 days in the summer period. Half of them were covered with a net with mesh size 2 cm to prevent effect of large predators. It was found that spatial pattern of invertebrates' sinking in the bay conforms to distribution of benthic communities. Larvae of benthic invertebrates sinks in general in places inhabited by their adult species. The main factors responsible for recolonzation are: sediment type and local hydrodynamic conditions. Heart-shaped sea urchin Echinocardium cordatum is numerically dominated in the bay on depth 3-4.5 m, but its larvae sinks in the deeper area. Community structure is supported by mature specimen migration to places inhabited by species. Predators affect largely on the species.

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Long-term evolution is thought to take opportunities that arise as a consequence of mass extinction (as argued, for example, by Gould, 2002) and the following biotic recovery, but there is absolutely no evidence for this being the case. However, our study shows that eutrophication by oceanic mixing also played a part in the enhancement of several evolutionary events amongst marine organisms, and these results could indicate that the rates of oceanic biodiversification may be slowed if upwelling becomes weakened by future global warming. This paper defines three distinct evolutionary events of resting spores of the marine diatom genus Chaetoceros, to reconstruct past upwelling through the analysis of several DSDP, ODP and land-based successions from the North, South and equatorial Pacific as well as the Atlantic Ocean during the past 40 million years. The Atlantic Chaetoceros Explosion (ACE) event occurred across the E/O boundary in the North Atlantic, and is characterized by resting spore diversification that occurred as a consequence of the onset of upwelling following changes in thermohaline circulation through global cooling in the early Oligocene. Pacific Chaetoceros Explosion events-1 and -2 (PACE-1 and PACE-2) are characterized by relatively higher occurrences of iron input following the Himalayan uplift and aridification at 8.5 Ma and ca. 2.5 Ma in the North Pacific region. These events not only enhanced the diversification and increased abundance of primary producers, including that of Chaetoceros, other diatoms and seaweeds, but also stimulated the evolution of zooplankton and larger predators, such as copepods and marine mammals, which ate these phytoplankton and plants. Current thinking suggests new evolutionary niches open up after a mass extinction, but our study finds that eutrophication can also stimulate evolutionary diversification. Moreover, in the opposite fashion, our results show that as thermohaline circulation abates, global warming progresses and the ocean surface becomes warmer, many marine organisms will be affected by the environmental degradation.

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According to the drilling probes of the Deep Waier Drilling Project, Neogene sediments in a tropical area of the Pacific Ocean are divided into 15 zones based on diatoms. The author shows that a unique zonation may be applied for the entire region. Identification of diatoms zones boundaries was conducted through their direct correlation with nannoplancton, radiolarian and foraminiferal zonal sceals. Their ultra-structure and morphological relationship are being analysed. The mode of siliceous accumulation within the equatorial belt differed through the western central and eastern region since the early Miocene and the difference become more evident from the end of Middle Miocene. The distribution of Neogene diatomaceous silt in the tropical area is controlled by the character of gyre-water circulation and agrees with the modern geographical zonation.

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At present time, there is a lack of knowledge on the interannual climate-related variability of zooplankton communities of the tropical Atlantic, central Mediterranean Sea, Caspian Sea, and Aral Sea, due to the absence of appropriate databases. In the mid latitudes, the North Atlantic Oscillation (NAO) is the dominant mode of atmospheric fluctuations over eastern North America, the northern Atlantic Ocean and Europe. Therefore, one of the issues that need to be addressed through data synthesis is the evaluation of interannual patterns in species abundance and species diversity over these regions in regard to the NAO. The database has been used to investigate the ecological role of the NAO in interannual variations of mesozooplankton abundance and biomass along the zonal array of the NAO influence. Basic approach to the proposed research involved: (1) development of co-operation between experts and data holders in Ukraine, Russia, Kazakhstan, Azerbaijan, UK, and USA to rescue and compile the oceanographic data sets and release them on CD-ROM, (2) organization and compilation of a database based on FSU cruises to the above regions, (3) analysis of the basin-scale interannual variability of the zooplankton species abundance, biomass, and species diversity.