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Sample records for larvae artemia salina

  1. Acute toxicity of furazolidone on Artemia salina, Daphnia magna, and Culex pipiens molestus larvae

    SciTech Connect

    Macri, A.; Stazi, A.V.; Dojmi di Delupis, G.

    1988-10-01

    As a result of evidence of the ecotoxicity of nitrofurans, the acute toxicity of furazolidone was tested in vivo on two aquatic organisms, Artemia salina and Daphnia magna, which are both crustaceans. Toxicity studies were also performed on larvae of Culex pipiens molestus. Results indicated a significant toxicity of the compound on Culex pipiens and Daphnia magna, while Artemia salina proved to be the least sensitive.

  2. Evaluation of Alpha and Gamma Aluminum Oxide Nanoparticle Accumulation, Toxicity and Depuration in Artemia Salina Larvae

    PubMed Central

    Ates, Mehmet; Demir, Veysel; Arslan, Zikri; Daniels, James; Farah, Ibrahim O.; Bogatu, Corneliu

    2014-01-01

    In this study, Artemia salina (crustacean filter feeders) larvae were used as a test model to investigate the toxicity of aluminum oxide nanoparticles (Al2O3 NPs) on marine microorganisms. The uptake, toxicity and elimination of α-Al2O3 (50 nm and 3.5 μm) and γ-Al2O3 (5 nm and 0.4 μm) NPs were studied. Twenty-four and ninety-six hour exposures of different concentrations of Al2O3 NPs to Artemia larvae were conducted in a seawater medium. When suspended in water, Al2O3 NPs aggregated substantially with the sizes ranging from 6.3 nm to > 0.3 μm for spherical NPs, and from 250 to 756 nm for rod-shaped NPs. The phase contrast microscope images revealed that NPs deposited inside the guts as aggregates. ICP-MS analysis showed that large particles (3.5 μm α-Al2O3) were not taken up by Artemia, while fine NPs (0.4 μm γ-Al2O3) and ultra-fine NPs (5 nm γ-Al2O3 and 50 nm α-Al2O3) accumulated substantially. Differences in toxicity were detected as changing with NP size and morphology. The malondialdehyde (MDA) levels indicated that smaller γ-Al2O3 (5 nm) NPs were more toxic than larger γ-Al2O3 (0.4 μm) particulates in 96 h. The highest mortality was measured as 34% in 96 h for γ-Al2O3 NPs (5 nm) at 100 mg/L (LC50 > 100 mg/L). γ-Al2O3 NPs were more toxic than α-Al2O3 NPs at in all conditions. PMID:24753078

  3. Evaluation of alpha and gamma aluminum oxide nanoparticle accumulation, toxicity, and depuration in Artemia salina larvae.

    PubMed

    Ates, Mehmet; Demir, Veysel; Arslan, Zikri; Daniels, James; Farah, Ibrahim O; Bogatu, Corneliu

    2015-01-01

    In this study, Artemia salina (crustacean filter feeders) larvae were used as a test model to investigate the toxicity of aluminum oxide nanoparticles (Al2O3 NPs) on marine microorganisms. The uptake, toxicity, and elimination of α-Al2O3 (50 nm and 3.5 μm) and γ-Al2O3 (5 nm and 0.4 μm) NPs were studied. Twenty-four and ninety-six hour exposures of different concentrations of Al2O3 NPs to Artemia larvae were conducted in a seawater medium. When suspended in water, Al2O3 NPs aggregated substantially with the sizes ranging from 6.3 nm to >0.3 µm for spherical NPs and from 250 to 756 nm for rod-shaped NPs. The phase contrast microscope images showed that NPs deposited inside the guts as aggregates. Inductively coupled plasma mass spectrometry analysis showed that large particles (3.5 μm α-Al2O3) were not taken up by Artemia, whereas fine NPs (0.4 μm γ-Al2O3) and ultra-fine NPs (5 nm γ-Al2O3 and 50 nm α-Al2O3) accumulated substantially. Differences in toxicity were detected as changing with NP size and morphology. The malondialdehyde levels indicated that smaller γ-Al2O3 (5 nm) NPs were more toxic than larger γ-Al2O3 (0.4 µm) particulates in 96 h. The highest mortality was measured as 34% in 96 h for γ-Al2O3 NPs (5 nm) at 100 mg/L (LC50 > 100 mg/L). γ-Al2O3 NPs were more toxic than α-Al2O3 NPs at all conditions.

  4. Effects of selected metal oxide nanoparticles on Artemia salina larvae: evaluation of mortality and behavioural and biochemical responses.

    PubMed

    Gambardella, Chiara; Mesarič, Tina; Milivojević, Tamara; Sepčić, Kristina; Gallus, Lorenzo; Carbone, Serena; Ferrando, Sara; Faimali, Marco

    2014-07-01

    The aim was to investigate the toxicity of selected metal oxide nanoparticles (MO-NPs) on the brine shrimp Artemia salina, by evaluating mortality and behavioural and biochemical responses. Larvae were exposed to tin(IV) oxide (stannic oxide (SnO2)), cerium(IV) oxide (CeO2) and iron(II, III) oxide (Fe3O4) NPs for 48 h in seawater, with MO-NP suspensions from 0.01 to 1.0 mg/mL. Mortality and behavioural responses (swimming speed alteration) and enzymatic activities of cholinesterase, glutathione-S-transferase and catalase were evaluated. Although the MO-NPs did not induce any mortality of the larvae, they caused changes in behavioural and biochemical responses. Swimming speed significantly decreased in larvae exposed to CeO2 NPs. Cholinesterase and glutathione-S-transferase activities were significantly inhibited in larvae exposed to SnO2 NPs, whereas cholinesterase activity significantly increased after CeO2 NP and Fe3O4 NP exposure. Catalase activity significantly increased in larvae exposed to Fe3O4 NPs. In conclusion, swimming alteration and cholinesterase activity represent valid endpoints for MO-NP exposure, while glutathione-S-transferase and catalase activities appear to be NP-specific. PMID:24590232

  5. The lethality of Euphorbia conspicua to adults of Biomphalaria glabrata, cercaria of Schistosoma mansoni and larvae of Artemia salina.

    PubMed

    dos Santos, Aldenir F; de Azevedo, Denise P L; dos Santos Mata, Rosalina da C; de Mendonça, Dina I M Dinis; Sant'Ana, Antônio E Goulart

    2007-01-01

    Leaf extracts of Euphorbia conspicua (Euphorbiaceae), together with the latex and fractions derived therefrom, were evaluated for their molluscicidal and cercaricidal activities and their toxicities to brine shrimps. Whilst the leaf extracts were inactive against Biomphalaria glabrata, the latex, its triterpenic fraction and irritant fractions I and II exhibited high activities against adult snails with LC90 values of 4.87, 10.55, 0.64 and 0.10 microg/mL, respectively. The latex and its derived fractions were considered lethal to the cercaria of Schistosoma mansoni at concentrations of 100 microg/mL. The toxicities of the latex and the irritant fractions, but not of the triterpenic fraction, against Artemia salina were high with LC50 values < 10 microg/mL. The possible application of the latex of E. conspicua as an alternative natural molluscicide is considered.

  6. High surface adsorption properties of carbon-based nanomaterials are responsible for mortality, swimming inhibition, and biochemical responses in Artemia salina larvae.

    PubMed

    Mesarič, Tina; Gambardella, Chiara; Milivojević, Tamara; Faimali, Marco; Drobne, Damjana; Falugi, Carla; Makovec, Darko; Jemec, Anita; Sepčić, Kristina

    2015-06-01

    We investigated the effects of three different carbon-based nanomaterials on brine shrimp (Artemia salina) larvae. The larvae were exposed to different concentrations of carbon black, graphene oxide, and multiwall carbon nanotubes for 48 h, and observed using phase contrast and scanning electron microscopy. Acute (mortality) and behavioural (swimming speed alteration) responses and cholinesterase, glutathione-S-transferase and catalase enzyme activities were evaluated. These nanomaterials were ingested and concentrated in the gut, and attached onto the body surface of the A. salina larvae. This attachment was responsible for concentration-dependent inhibition of larval swimming, and partly for alterations in the enzyme activities, that differed according to the type of tested nanomaterials. No lethal effects were observed up to 0.5mg/mL carbon black and 0.1mg/mL multiwall carbon nanotubes, while graphene oxide showed a threshold whereby it had no effects at 0.6 mg/mL, and more than 90% mortality at 0.7 mg/mL. Risk quotients calculated on the basis of predicted environmental concentrations indicate that carbon black and multiwall carbon nanotubes currently do not pose a serious risk to the marine environment, however if uncontrolled release of nanomaterials continues, this scenario can rapidly change. PMID:25889088

  7. Comparative evaluation of impact of Zn and ZnO nanoparticles on brine shrimp (Artemia salina) larvae: effects of particle size and solubility on toxicity

    PubMed Central

    Ates, Mehmet; Daniels, James; Farah, Ibrahim O.; Rivera, Hilsamar Félix

    2012-01-01

    Brine shrimp (Artemia salina) larvae were exposed to different sizes of zinc (Zn) and zinc oxide (ZnO) nanoparticles (NPs) to evaluate their toxicity in marine aquatic ecosystems. Acute exposure was conducted in seawater with 10, 50 and 100 mg/L concentrations of the NPs for 24 h and 96 h. Phase contrast microscope images confirmed the accumulation of the NPs inside the guts. Artemia were unable to eliminate the ingested particles, which was thought to occur due the formation of massive particles in the guts. Although the suspensions of the NPs did not exhibit any significant acute toxicity within 24 h, mortalities increased remarkably in 96 h and escalated with increasing concentration of NP suspension to 42% for Zn NPs (40-60 nm) (LC50 ~100 mg/L) and to about 34% for ZnO NPs (10-30 nm) (LC50 >100 mg/L). The suspensions of Zn NPs were more toxic to Artemia than those of ZnO NPs under comparable regimes. This effect was attributed to higher Zn2+ levels (ca. up to 8.9 mg L-1) released to the medium from Zn NPs in comparison to that measured in the suspensions of ZnO NPs (ca. 5.5 mg L-1). In addition, the size of the nanopowders appeared to contribute to the observed toxicities. Although the suspensions possessed aggregates of comparable sizes, smaller Zn NPs (40-60 nm) were relatively more toxic than larger Zn NPs (80-100 nm). Likewise, the suspensions of 10-30 nm ZnO NPs caused higher than those of 200 nm ZnO NPs. Lipid peroxidation levels were substantially higher in 96 h (p<0.05) indicating that the toxic effects were due to the oxidative stress. PMID:24058731

  8. Specific anion effects in Artemia salina.

    PubMed

    Lo Nostro, Pierandrea; Ninham, Barry W; Carretti, Emiliano; Dei, Luigi; Baglioni, Piero

    2015-09-01

    The specific anion effect on the vitality of Artemia salina was investigated by measuring the Lethal Time LT50 of the crustaceans in the presence of different sodium salts solutions at room temperature and at the same ionic strength as natural seawater. Fluoride, thiocyanate and perchlorate are the most toxic agents, while chloride, bromide and sulfate are well tolerated. The rates of oxygen consumption of brine shrimps were recorded in mixed NaCl+NaF or NaCl+NaSCN solutions as a function of time. The results are discussed in terms of the Hofmeister series, and suggest that, besides the biochemical processes that involve F(-), SCN(-) and ClO4(-), the different physico-chemical properties of the strong kosmotropic and chaotropic anions may contribute in determining their strong toxicity for A. salina. PMID:25978674

  9. The swimming mechanics of Artemia Salina

    NASA Astrophysics Data System (ADS)

    Ruiz-Angulo, A.; Ramos-Musalem, A. K.; Zenit, R.

    2013-11-01

    An experimental study to analyze the swimming strategy of a small crustacean (Artemia Salina) was conducted. This animal has a series of eleven pairs of paddle-like appendices in its thorax. These legs move in metachronal-wave fashion to achieve locomotion. To quantify the swimming performance, both high speed video recordings of the legs motion and time-resolved PIV measurements of the induced propulsive jet were conducted. Experiments were conducted for both tethered and freely swimming specimens. We found that despite their small size, the propulsion is achieved by an inertial mechanism. An analysis of the efficiency of the leg wave-like motion is presented and discussed. A brief discussion on the mixing capability of the induced flow is also presented.

  10. Acute toxicity of organic solvents on Artemia salina

    SciTech Connect

    Barahona-Gomariz, M.V.; Sanz-Barrera, F.; Sanchez-Fortun, S. )

    1994-05-01

    Organic solvents can make their way into the environment as industrial wastes and components of pesticide formulation. In laboratory bioassays, the use of organic formulations. In laboratory bioassays, the use of organic solvents is often unavoidable, since many pesticides and organic pollutants have low water solubility and must be dissolved in organic solvents prior to addition into experimental systems. In the toxicant bioassays, invertebrates with special reference to aquatic arthropod species are of recent interest as test models due to the need for developing nonmammalian test systems. Toxic effects of organic solvents have been tested with a few aquatic species, but information on the comparative toxicity of solvents towards Artemia salina is not available. Artemia salina have, within recent years, gained popularity as test organisms for short-term toxicity testing. Because Artemia salina exhibit rapid development and growth within 48 hr after hatch, their potential as a model organism for toxicology screening has been considered. To do this, synchronous populations of Artemia salina at different development intervals must be available.

  11. Effect of petroleum oil, pesticides, PCBs and other environmental contaminants on the hatchability of Artemia salina dry eggs

    SciTech Connect

    Kuwabara, K.; Nakamura, A.; Kashimoto, T.

    1980-07-01

    Artemia salina Leach is well-known as the brine shrimp used as tropical fish food and its dry eggs are easily obtained at a pet-shop at any season. One or two days after placing the dry eggs into salt water, the nauplius larvae of Artemia begins to hatch. In this paper, the methodlogy on a hatchability test for environmental contaminants and their effects on the dry egg hatchabilities are presented.

  12. Cyanobacterial cytotoxicity versus toxicity to brine shrimp Artemia salina.

    PubMed

    Hisem, Daniel; Hrouzek, Pavel; Tomek, Petr; Tomšíčková, Jana; Zapomělová, Eliška; Skácelová, Kateřina; Lukešová, Alena; Kopecký, Jiří

    2011-01-01

    Heterocytous cyanobacteria from various habitats were screened for toxicity to brine shrimp Artemia salina and the murine lymphoblastic cell line Sp/2 in order to compare these two testing models for evaluation of risk posed by cyanobacteria to human health. Methanol extracts of biomass and cultivation media were tested for toxicity and selected extracts were fractionated to determine the active fraction. We found a significant toxic effect to A. salina and to Sp/2 cells in 5.2% and 31% of studied extracts, respectively. Only 8.6% of the tested strains were highly toxic to both A. salina and the Sp/2 cell line, and only two of the tested strains were toxic to A. salina and not to the murine cell line. Therefore, it is likely that the toxic effect of cyanobacterial secondary metabolites mostly targets basal metabolic pathways present in mammal cells and so is not manifested in A. salina. We conclude that it is insufficient to monitor cytotoxicity of cyanobacteria using only the brine shrimp bioassay as was usual in the past, since cytotoxicity is a more frequent feature in cyanobacteria in comparison with toxicity to A. salina. A. salina toxicity test should not be used when estimating the possible health risk for humans. We suggest that in vitro mammal cells be used for these purposes. PMID:20946912

  13. SALT EFFECTS ON EGGS AND NAUPLII OF ARTEMIA SALINA L.

    PubMed

    Boone, E; Baas-Becking, L G

    1931-07-20

    Eggs of Artemia salina L., the brine shrimp, are easily obtainable in large quantities. Ecdysis takes place in two stages: (a) extrusion of the inner membrane, and (b) ecdysis of the nauplius from that membrane. The conditions which allow for the former are much more varied than those for the latter. Nauplii form in only solutions of a few sodium salts; and, in Mg, Ca, and Sr salts, potassium is very toxic. The possible environment for the nauplii (1 M total molarity) has been ascertained for chlorides of Na, K, Mg, and Ca. The facts observed account for the peculiar distribution of the organism.

  14. Mitochondrial biogenesis during differentiation of Artemia salina cysts.

    PubMed

    Schmitt, H; Grossfeld, H; Littauer, U Z

    1973-09-01

    Mitochondria isolated from cysts of Artemia salina (brine shrimp) were found to be devoid of cristae and to possess a low respiratory capability. Hydration of the cysts induces marked biochemical and morphological changes in the mitochondria. Their biogenesis proceeds in two stages. The first stage is completed within 1 h and is characterized by a rapid increase in the respiratory capability of the mitochondria, their cytochrome oxidase, cytochrome b, cytochrome c and perhaps some morphological changes. In the second stage there is an increase in the protein-synthesizing capacity of the mitochondria as well as striking changes in mitochondrial morphology leading to the formation of cristae. PMID:4355924

  15. Preliminary results of the Artemia salina experiments in biostack on LDEF

    NASA Technical Reports Server (NTRS)

    Graul, E. H.; Ruether, W.; Hiendl, C. O.

    1992-01-01

    The mosaic egg of the brine shrimp, Artemia salina, resting in blastula or gastrula state represents a system that during further development, proceeds without any further development to the larval stage, the free swimming nauplius. Therefore, injury to a single cell of the egg will be manifest in the larvae. In several experiments, it was shown that the passage of a single heavy ion through the shrimp egg damaged a cellular area large enough to disturb either embryogenesis or further development of the larvae, or the integrity of the adult individual. Emergence from the egg shell was heavily disturbed by the heavy ions as was hatching. Additional late effects, due to a hit by a heavy ion, are delayed of growth and of sexual maturity, and reduced fertility. Anomalies in the body and the extremities could be observed more frequently for the nauplii which had developed from eggs hit by heavy ions.

  16. Toxic Assessment of Triclosan and Triclocarban on Artemia salina.

    PubMed

    Xu, Xiaolu; Lu, Yin; Zhang, Deyong; Wang, Yinyin; Zhou, Xianshan; Xu, Huiying; Mei, Yu

    2015-12-01

    In this study, we investigated the possible acute toxic and genotoxic effects of triclosan (TCS) and triclocarban (TCC) on Artemia salina. Genotoxicity was evaluated using single-cell gel electrophoresis and apoptotic frequency assays (Annexin V-FITC/PI assay). Acute toxicity test results showed that TCC (LC50-24 h = 17.8 µg/L) was more toxic than TCS (LC50-24 h = 171.1 µg/L). Significant increases in both genotoxic biomarkers were observed at 24 h after initial exposure, indicating that these two chemicals are potentially dangerous for this aquatic biological model. Although further studies are required, a comparison of data both in vitro and in vivo allowed us to suggest possible mechanisms of action for TCS and TCC in this sentinel organism.

  17. Assessment of toxicity of Moringa oleifera flower extract to Biomphalaria glabrata, Schistosoma mansoni and Artemia salina.

    PubMed

    Rocha-Filho, Cláudio A A; Albuquerque, Lidiane P; Silva, Luanna R S; Silva, Patrícia C B; Coelho, Luana C B B; Navarro, Daniela M A F; Albuquerque, Monica C P A; Melo, Ana Maria M A; Napoleão, Thiago H; Pontual, Emmanuel V; Paiva, Patrícia M G

    2015-08-01

    This study reports the effect of an aqueous extract from Moringa oleifera Lam. flowers on Biomphalaria glabrata embryos and adults and on Schistosoma mansoni adult worms. The extract contains tannins, saponins, flavones, flavonols, xanthones, and trypsin inhibitor activity. The toxicity of the extract on Artemia salina larvae was also investigated to determine the safety of its use for schistosomiasis control. After incubation for 24h, the flower extract significantly (p<0.05) delayed the development of B. glabrata embryos and promoted mortality of adult snails (LC50: 2.37±0.5mgmL(-1)). Furthermore, treatment with the extract disrupted the development of embryos generated by snails, with most of them remaining in the blastula stage while control embryos were already in the gastrula stage. Flower extract killed A. salina larvae with a LC50 value (0.2±0.015mgmL(-1)) lower than that determined for snails. A small reduction (17%) in molluscicidal activity was detected when flower extract (2.37mgmL(-1)) was exposed to tropical environmental conditions (UVI index ranging from 1 to 14, temperature from 25 to 30°C, and 65% relative humidity). Toxicity to A. salina was also reduced (LC50 value of 0.28±0.01mgmL(-1)). In conclusion, M. oleifera flower extract had deleterious effects on B. glabrata adults and embryos. However, unrestricted use to control schistosomiasis should be avoided due to the toxicity of this extract on A. salina.

  18. Assessment of toxicity of Moringa oleifera flower extract to Biomphalaria glabrata, Schistosoma mansoni and Artemia salina.

    PubMed

    Rocha-Filho, Cláudio A A; Albuquerque, Lidiane P; Silva, Luanna R S; Silva, Patrícia C B; Coelho, Luana C B B; Navarro, Daniela M A F; Albuquerque, Monica C P A; Melo, Ana Maria M A; Napoleão, Thiago H; Pontual, Emmanuel V; Paiva, Patrícia M G

    2015-08-01

    This study reports the effect of an aqueous extract from Moringa oleifera Lam. flowers on Biomphalaria glabrata embryos and adults and on Schistosoma mansoni adult worms. The extract contains tannins, saponins, flavones, flavonols, xanthones, and trypsin inhibitor activity. The toxicity of the extract on Artemia salina larvae was also investigated to determine the safety of its use for schistosomiasis control. After incubation for 24h, the flower extract significantly (p<0.05) delayed the development of B. glabrata embryos and promoted mortality of adult snails (LC50: 2.37±0.5mgmL(-1)). Furthermore, treatment with the extract disrupted the development of embryos generated by snails, with most of them remaining in the blastula stage while control embryos were already in the gastrula stage. Flower extract killed A. salina larvae with a LC50 value (0.2±0.015mgmL(-1)) lower than that determined for snails. A small reduction (17%) in molluscicidal activity was detected when flower extract (2.37mgmL(-1)) was exposed to tropical environmental conditions (UVI index ranging from 1 to 14, temperature from 25 to 30°C, and 65% relative humidity). Toxicity to A. salina was also reduced (LC50 value of 0.28±0.01mgmL(-1)). In conclusion, M. oleifera flower extract had deleterious effects on B. glabrata adults and embryos. However, unrestricted use to control schistosomiasis should be avoided due to the toxicity of this extract on A. salina. PMID:25867917

  19. Purification and characterization of a carboxymethyl cellulase from Artemia salina.

    PubMed

    Zin, Hyun Woo; Park, Kwang-Hyun; Choi, Tae Jin

    2014-01-01

    Brine shrimp (Artemia salina) belong to a group of crustaceans that feed on microalgae and require a cellulase enzyme that can be used in ethanol production from marine algae. Protein with potential cellulase activity was purified and the activity analyzed under different conditions. After initial identification of cellulase activity by CMC cellulase, surface sterilization and PCR using 16s rRNA primers was conducted to confirm that the cellulase activity was not produced from contaminating bacteria. The enzyme was purified by ammonium sulfate fractionation, gel filtration, and ion exchange chromatography. After the final purification, a 70-fold increase in specific enzyme activity was observed. SDS-PAGE results revealed that the cellulase enzyme had a molecular mass of 96 kDa. Temperature, pH, and salinity values were found to be optimal at 55 °C, pH 8.0, and 600 mM NaCl, respectively. Specifically, the enzyme showed a fivefold increase in enzyme activity in seawater compared to 600 mM NaCl in phosphate buffer. Further analysis of the purified enzyme by molecular spectrometry showed no match to known cellulases, indicating this enzyme could be a novel halophilic cellulase that can be used for the production of bioethanol from marine macroalgae. PMID:24291747

  20. [Detection of fungal metabolites showing toxic activity through Artemia salina bioassay].

    PubMed

    González, Ana María; Presa, Maximiliano; Latorre, María Gabriela; Lurá, María Cristina

    2007-03-01

    The aim of this study was to detect toxic metabolites from fungi contaminating food and medicinal herbs by applying the toxicity assay to Artemia salina. According to toxicity percentages, the extracts were classified as nontoxic (NT), slightly toxic (ST), toxic (T) and highly toxic (HT). Those classified as T and HT were assayed for mycotoxins. Only 6 out of 71 strains were found to be T (8.5%) for A. salina. Penicillium brevicompactum Dierckx, isolated from sausages, was found to be HT, mainly due to the presence of ochratoxin A and two other unidentified metabolites. PMID:17592895

  1. Bioactivity evaluation against Artemia salina Leach of medicinal plants used in Brazilian Northeastern folk medicine.

    PubMed

    Arcanjo, D D R; Albuquerque, A C M; Melo-Neto, B; Santana, L C L R; Medeiros, M G F; Citó, Amgl

    2012-08-01

    The brine shrimp (Artemia salina Leach) lethality bioassay offers an advantage in standardization and quality control of botanical products. This test is well correlated with antitumor activity (cytotoxicity) and can be used to monitor the activity of bioactive natural products. This paper reports the bioactivity of ethanol extracts from seven medicinal plants from the Northeast of Brazil (Acmella uliginosa, Ageratum conyzoides, Eugenia uniflora, Plectranthus neochilus, Moringa oleifera, Justicia pectoralis and Equisetum sp.) against Artemia salina. Biological activity was evaluated for extracts at 1, 10, 100, and 1000 µg/mL in triplicate, and the mean lethal concentration values (LC50) were obtained by probit analysis. The species Acmella uliginosa showed the highest bioactivity, and its flower extract was more active than its leaf extract. PMID:22990821

  2. Bioactivity evaluation against Artemia salina Leach of medicinal plants used in Brazilian Northeastern folk medicine.

    PubMed

    Arcanjo, D D R; Albuquerque, A C M; Melo-Neto, B; Santana, L C L R; Medeiros, M G F; Citó, Amgl

    2012-08-01

    The brine shrimp (Artemia salina Leach) lethality bioassay offers an advantage in standardization and quality control of botanical products. This test is well correlated with antitumor activity (cytotoxicity) and can be used to monitor the activity of bioactive natural products. This paper reports the bioactivity of ethanol extracts from seven medicinal plants from the Northeast of Brazil (Acmella uliginosa, Ageratum conyzoides, Eugenia uniflora, Plectranthus neochilus, Moringa oleifera, Justicia pectoralis and Equisetum sp.) against Artemia salina. Biological activity was evaluated for extracts at 1, 10, 100, and 1000 µg/mL in triplicate, and the mean lethal concentration values (LC50) were obtained by probit analysis. The species Acmella uliginosa showed the highest bioactivity, and its flower extract was more active than its leaf extract.

  3. On the motility of living invertebrates The case of Artemia Salina

    NASA Astrophysics Data System (ADS)

    Huerta, R.; Hernández, A.; Alvarado-Gil, J. J.

    1998-08-01

    Using a laser beam deflection technique a non-destructive and non-invasive method is developed. This method is applied to monitor the motility of small invertebrates, in particular we study the important case of the crustacean Artemia Salina and the motion of its different parts. We find out that its dynamics can be explained as a superposition of several periodic motions with very well defined frequencies.

  4. Cadmium and zinc reversibly arrest development of Artemia larvae

    SciTech Connect

    Bagshaw, J.C.; Rafiee, P.; Matthews, C.O.; MacRae, T.H.

    1986-08-01

    Despite the widespread distribution of heavy metals such as cadmium and zinc in the environment and their well-known cytotoxicity and embryotoxicity in mammals, comparatively little is known about their effect on aquatic organisms, particularly invertebrates. Post-gastrula and early larval development of the brine shrimp, Artemia, present some useful advantages for studies of developmental aspects of environmental toxicology. Dormant encysted gastrulae, erroneously called brine shrimp eggs, can be obtained commercially and raised in the laboratory under completely defined conditions. Following a period of post-gastrula development within the cyst, pre-nauplius larvae emerge through a crack in the cyst shell. A few hours later, free-swimming nauplius larvae hatch. Cadmium is acutely toxic to both adults and nauplius larvae of Artemia, but the reported LC50s are as high as 10 mM, depending on larval age. In this paper the authors show that pre-nauplius larvae prior to hatching are much more sensitive to cadmium than are hatched nauplius larvae. At 0.1 ..mu..m, cadmium retards development and hatching of larvae; higher concentrations block hatching almost completely and thus are lethal. However, the larvae arrested at the emergence stage survive for 24 hours or more before succumbing to the effects of cadmium, and during this period the potentially lethal effect is reversible if the larvae are placed in cadmium-free medium. The effects of zinc parallel those of cadmium, although zinc is somewhat less toxic than cadmium at equal concentrations.

  5. Nutritional Composition, in vitro Antioxidant Activity and Artemia salina L. Lethality of Pulp and Seed of Tamarindus indica L. Extracts.

    PubMed

    Khairunnuur, F A; Zulkhairi, A; Azrina, A; Moklas, Ma M; Khairullizam, S; Zamree, M S; Shahidan, M A

    2009-03-01

    This study was designed to examine the nutritional composition, antioxidant activity and medium lethal concentration (LC50 value) of Tamarindus indica L. pulp and seed extracts in vitro. The extraction was set at 40◦C, 60◦C and 100◦C for 12 hours, 6 hours and 15 minutes respectively to determine the optimum extraction parameter whereas the anti-oxidant activity of the extracts was measured using iron (III) reduction (FRAP) assay. Total phenolic content (TPC) of the extracts was estimated as gallic acid equivalent by Folin-Ciocalteau method. Toxicity potential of the extract was assessed in vitro by Artemia salina lethality test both in seed and pulp samples. The results showed that tamarind seed contained a higher percentage of carbohydrate, protein, fat and energy (15%, 82%, 95% and 33.13% respectively) than the pulp. On the other hand, the pulp demonstrated a high moisture (51.1%) and ash (34.84%) content than the seed. For the mineral analysis, tamarind seed contained higher Ca and C (1.0% and 50.73% respectively) than the pulp (0.27% and 40.40% respectively). No heavy metals were detected in both samples. Seed extracted at 60◦C/6 hours and 100◦C/15 minutes showed the highest TPC value and were significantly different (p<0.05) than the seed extracted at 40◦C/12 hours. Anti-oxidant activity is positively correlated to the TPC value of the extracts (R=0.991). The pulp and seed extracted at 100◦C/15 minutes showed the highest FRAP value among its groups (216.17 ± 14.06 μmol (Fe)/g and 659.74 ± 16.40 μmol (Fe)/g respectively). This study indicates that tamarind pulp and seed extracts possess beneficial antioxidant properties and the optimum extraction parameter is 100◦C for 15 minutes. In Artemia salina lethality test, tamarind pulp caused significant mortality of the crustacean larvae with LC50 in the range of 26-28 μL/mL. Tamarind seed were not toxic to Artemia salina since the LC50 of the extracts was higher than 1000 μL/mL.

  6. Nutritional Composition, in vitro Antioxidant Activity and Artemia salina L. Lethality of Pulp and Seed of Tamarindus indica L. Extracts.

    PubMed

    Khairunnuur, F A; Zulkhairi, A; Azrina, A; Moklas, Ma M; Khairullizam, S; Zamree, M S; Shahidan, M A

    2009-03-01

    This study was designed to examine the nutritional composition, antioxidant activity and medium lethal concentration (LC50 value) of Tamarindus indica L. pulp and seed extracts in vitro. The extraction was set at 40◦C, 60◦C and 100◦C for 12 hours, 6 hours and 15 minutes respectively to determine the optimum extraction parameter whereas the anti-oxidant activity of the extracts was measured using iron (III) reduction (FRAP) assay. Total phenolic content (TPC) of the extracts was estimated as gallic acid equivalent by Folin-Ciocalteau method. Toxicity potential of the extract was assessed in vitro by Artemia salina lethality test both in seed and pulp samples. The results showed that tamarind seed contained a higher percentage of carbohydrate, protein, fat and energy (15%, 82%, 95% and 33.13% respectively) than the pulp. On the other hand, the pulp demonstrated a high moisture (51.1%) and ash (34.84%) content than the seed. For the mineral analysis, tamarind seed contained higher Ca and C (1.0% and 50.73% respectively) than the pulp (0.27% and 40.40% respectively). No heavy metals were detected in both samples. Seed extracted at 60◦C/6 hours and 100◦C/15 minutes showed the highest TPC value and were significantly different (p<0.05) than the seed extracted at 40◦C/12 hours. Anti-oxidant activity is positively correlated to the TPC value of the extracts (R=0.991). The pulp and seed extracted at 100◦C/15 minutes showed the highest FRAP value among its groups (216.17 ± 14.06 μmol (Fe)/g and 659.74 ± 16.40 μmol (Fe)/g respectively). This study indicates that tamarind pulp and seed extracts possess beneficial antioxidant properties and the optimum extraction parameter is 100◦C for 15 minutes. In Artemia salina lethality test, tamarind pulp caused significant mortality of the crustacean larvae with LC50 in the range of 26-28 μL/mL. Tamarind seed were not toxic to Artemia salina since the LC50 of the extracts was higher than 1000 μL/mL. PMID:22691806

  7. Effects of aqueous suspensions of titanium dioxide nanoparticles on Artemia salina: assessment of nanoparticle aggregation, accumulation and toxicity

    PubMed Central

    Ates, Mehmet; Daniels, James; Arslan, Zikri; Farah, Ibrahim O.

    2012-01-01

    Aquatic stability and impact of titanium dioxide nanoparticles (TiO2 NPs, 10-30 nm) was investigated using Artemia salina. Acute exposure was conducted on nauplii (larvae) and adults in seawater in a concentration range from 10 to 100 mg/L TiO2 NPs for 24 h and 96 h. Rapid aggregation occurred in all suspensions of TiO2 NPs to form micrometer size particles. Yet, both nauplii and adults accumulated the aggregates significantly. Average TiO2 content in nauplii ranged from 0.47 to 3.19 mg/g and from 1.29 to 4.43 mg/g in 24 h and 96 h, respectively. Accumulation in adults was higher ranging from 2.30 to 4.19 mg/g and from 4.38 to 6.20 mg/g in 24 h and 96 h, respectively. Phase contrast microscopy images revealed that Artemia were unable to excrete the particles. Thus, the TiO2 aggregates filled inside the guts. No significant mortality or toxicity occurred within 24 h at any dose. Lipid peroxidation levels characterized with malondialdehyde (MDA) concentrations were not statistically different from those of the controls (p>0.05). These results suggested that suspensions of the TiO2 NPs were nontoxic to Artemia, most likely due to the formation of benign TiO2 aggregates in water. In contrast, both mortality and lipid peroxidation increased in extended exposure to 96 h. Highest mortality occurred in 100 mg/L TiO2 NP suspensions; 18% for nauplii and 14% for adults (LC50 > 100 mg/L). These effects were attributed to the particle loading inside the guts leading to oxidative stress as a result of impaired food uptake for a long period of time. PMID:22810381

  8. Study of cosmic ray effects on Artemia salina eggs during the Apollo 16 and 17 flights.

    PubMed

    Planel, H; Soleilhavoup, J P; Blanquet, Y; Kaiser, R

    1974-01-01

    We have used Artemia salina eggs, embedded in polyvinyl alcohol, to study the biological effects of heavy ions of cosmic rays. Each biological layer was sandwiched between track detectors. Hit eggs by heavy ions show a great inhibition of their developmental ability. A lower inhibition is observed for eggs that were flown but not hit. Simulation experiments are in progress to determine the factors responsible for inhibition of eggs that were not hit and to improve our knowledge of cellular damage induced by heavy ions.

  9. Oxygen-binding characteristics of three extracellular haemoglobins of Artemia salina.

    PubMed

    D'Hondt, J; Moens, L; Heip, J; D'Hondt, A; Kondo, M

    1978-06-01

    The oxygen-binding characteristics of the three extracellular haemoglobins of brine shrimp (Artemia salina) were studied in vitro by using highly purified preparations. Haemoglobin I is induced last in the development of brine shrimps when functional gills are formed. It has the lowest oxygen affinity (p(50) 5.34mmHg), an intermediate Bohr effect (ø -0.09 at 20 degrees C) above pH8 and a temperature-sensitivity (DeltaH -44.8 to -45.6kJ/mol at pH8-9) comparable with those observed with other invertebrate haemoglobins [Weber & Heidemann (1977) Comp. Biochem. Physiol. A57, 151-155]. Haemoglobin II, which is the first to be induced, soon after hatching of nauplius larvae, persists generally throughout the whole adult life. It has an intermediate oxygen affinity (p(50) 3.7mmHg), the highest Bohr effect (ø -0.21 at 20 degrees C) above pH8 and a similar temperature-sensitivity (DeltaH -46.0 to -54.8kJ/mol at pH8-9) as haemoglobin I. However, haemoglobin III, which is induced second several hours after the induction of haemoglobin II but disappearing from the haemolymph in the middle of adult life, has the highest oxygen affinity (p(50) 1.8mmHg), the lowest Bohr effect (ø -0.03 at 20 degrees C) above pH8.5 and a high resistance against temperature variation between 10 and 25 degrees C at pH8.5-9 (DeltaH -22.6 to -23.0kJ/mol). At pH7.5-8, haemoglobin III exhibits a similar temperature-sensitivity under 30 degrees C as do other haemoglobins. All three haemoglobins have a rather low co-operativity, with Hill coefficients (h 1.6-1.9 at pH8.5), which are dependent on both pH and temperature. The highest co-operativity was observed at 20 degrees C and pH9 for haemoglobins I and II, whereas it was at 27 degrees C and pH8.5 for haemoglobin III. Thus the oxygen-binding behaviour of haemoglobin III in vitro is significantly different from those of haemoglobins I and II and indicates possibly its specific physiological role in vivo in the adaptive process in the natural

  10. A bioassay using Artemia salina for detecting phototoxicity of plant coumarins.

    PubMed

    Ojala, T; Vuorela, P; Kiviranta, J; Vuorela, H; Hiltunen, R

    1999-12-01

    Artemia salina (brine shrimp) has been successfully used for toxicity testing, and a screening test for phototoxicity has been developed based on this method. The ability of the method to test the phototoxic potential of seven known compounds was investigated. Athamantin (an angular furanocoumarin) and umbelliferone (a simple coumarin) showed no phototoxicity, while linear furanocoumarins exhibited phototoxic activity in the following order: psoralen > bergapten > peucedanin > xanthotoxin. The applicability of this method was also tested in screening the phototoxicity of plant material. Six plants from Apiaceae [Aegopodium podagraria L., Anethum graveolens L., Angelica archangelica L., Levisticum officinalis Koch, Petroselinum crispum (P. Mill) A. W. Hill., and Peucedanum palustre (L.) Moench] and one from Rutaceae (Ruta graveolens L.) were selected, all of them known to contain furanocoumarins. Extracts from leaves collected at different times during the growth period were used in the screening. Our results were in accordance with the furanocoumarin content of these plants and with the results of other phototoxicity tests. The Artemia salina method proved to be rapid, simple and inexpensive, and is therefore ideal in the initial biological screening of large numbers of samples for simultaneous detection of both toxicity and phototoxicity. PMID:10630112

  11. Neuroanatomical clues to peripheral locomotor control in small crustaceans (Artemia salina).

    PubMed

    Kane, E S

    1975-08-01

    Brine shrimp (Artemia salina) were prepared for light and electron microscopy at several stages. Immersion-fixed, rapid Golgi impregnations demonstrated two distinct neuronal types in thoracic appendages of mature, freely swimming Artemia. Isolated motor neurons had large cell somas and thick, radiating dendrites at the body wall-limb junction. A long, elaborate axon extended into the limb. Groups of a second type of neuron with smaller somas and very thin, radiating processes occurred in the distal limb near presumably tactile bristles. Thick axons from motor neurons were traced to terminals associated with limb muscle. Both muscle and axon were best seen with Nomarski optics. Motor axons possessed elongate, irregularly shaped boutons en passant and morphologically variable boutons terminaux; the latter included huge endings with knobbed projectiles arising from thick collaterals, or smaller, round boutons from thin collaterals. In addition, a thick unidentified axon coursed longitudinally within the central body wall, sending short collaterals peripherally. The elaborate peripheral neurons described in this Golgi study may be anatomical correlates for the extraordinary coordination of mature brine shrimp. Because Artemia movements resemble those of leech and decapods, which have been studied extensively electrophysiologically, the possibility of similarly elaborate peripheral structures supplementing central control of locomotion in those invertebrates should be considered.

  12. [Biological and biochemical quality of the Artemia (Anostraca: Artemiidae) population from Real de Salinas saltworks, Calkiní, Campeche, Mexico].

    PubMed

    Rodríguez-Canché, Leticia G; Maldonado-Montiel, Teresita D N J; Carrillo Navarro, Luciano A

    2006-12-01

    Cysts of Artemia spp. collected from February 1997 to February 2000 in the Real de Salinas solar saltworks, Campeche, Mexico, were compared with Artemia franciscana (batch number 8,131 Microfeast Artemia Cysts, Texas, USA). The variables determined in these two populations were: number of cysts per gram, hatching percentage, hatching efficiency, hatching rate, hatching synchrony and hatching biomass, as well as diameter of the cysts and length of the nauplii (instar I). For Salinas, the average diameters of the encapsulated and decapsulated cysts were 230.5 +/- 4.14 and 221.8 +/- 3.39 microm, respectively. The thickness of the cyst shell was 4.35 +/- 0.68 microm and the length of the nauplii was 388.11 +/- 4.39 microm, this last value is among the smallest reported in the literature. For the commercial population of A. franciscana, the average diameters of the encapsulated and decapsulated cysts were 230.21 +/- 12.49 and 216.96 +/- 13.71, respectively. With respect to the corion thickness and length of the nauplii the values were 6.62 +/- 2.72 and 424.70 +/- 30.08, respectively. The protein value of the cysts (47.91 %) and nauplii (50.5 %) of Artemia population from Real de Salinas, are considered adequate to be used as food in aquaculture. The results indicate that the population from Real de Salinas presents positive features for its use in aquaculture in the region.

  13. Accumulation of mercury by Artemia populations of different salinas of Portugal

    SciTech Connect

    Boia, C.M.; Duarte, A.C.

    1995-12-31

    The total mercury content in samples of the brine shrimp Artemia, sediments, water, suspended matter and, when available, algae, from nine salines of Portugal, was evaluated, to find out how mercury present in its natural habitat accumulates in Artemia. This study, carried out between 1990 and 1993, was part of a larger research project aiming to contribute to the knowledge on mercury accumulation and its effects on Artemia. This crustacean is used worldwide for marine species feeding in aquafarms, including in Portugal. The following sampling sites were chosen: some salinas of the lagoon of Aveiro, situated in the northern region of Portugal and partially contaminated with mercury-, the salt-mines of Rio Maior, in the interior of the central region of the country, where there are no sediments (the floor is cemented); and salt-marshes in the Algarve, in the south of Portugal. Mercury was determined by cold vapor absorption espectrofotometry after digestion of samples with sulfuric acid and potassium permanganate, and reference materials have been used to control the analytical performance. The concentrations of total Hg varied from 0.014 to 0.36 mg/Kg in the sediments, 0 to 0.30 {micro}g/g in the Artemia, 0.17 to 0.84 {micro}g/l in the suspended matter and 0.09 to 0.56 {micro}g/l in the water. The content of mercury in the artemias was strongly related to the concentration in the sediments, except when the algae were present, because they also accumulate a significantly percentage of the mercury. No relationships could be established with the Hg in water or in suspended matter (in mass of Hg/volume of filtered water), because their, content in Hg varied a lot with time and weather conditions, such as the wind strength. The presence of Hg in the sediments was due either to significant containing Hg discharges or to the composition of the sediments, being more important in the case of clays.

  14. Toxicity of organophosphates on morphology and locomotor behavior in brine shrimp, Artemia salina.

    PubMed

    Venkateswara Rao, J; Kavitha, P; Jakka, N M; Sridhar, V; Usman, P K

    2007-08-01

    The acute toxicity and hatching success of four organophosphorus insecticides--acephate (ACEP), chlorpyrifos (CPP), monocrotophos (MCP), and profenofos (PF)--was studied in a short-term bioassay using brine shrimp, Artemia salina. Fifty percent hatchability inhibition concentration and median lethal concentration (LC(50)) values were calculated after probit transformation of the resulting data. Among the insecticides tested, CPP is found to be the most toxic and also to inhibit hatching success of A. salina cysts in a concentration-dependent manner. In addition, the effect of these pesticides on locomotor behavior (swimming speed) and morphologic differences were studied in LC(50)-exposed nauplii after 24 hours. The in vivo effect of these insecticides on acetylcholinesterase (Enzyme commission number (EC 3.1.1.7) activity was also determined in LC(50)-exposed nauplii after 24 hours. Maximum percent decrease in their swimming speed and significant morphologic alterations were noticed in CPP-exposed brine shrimps. The order of toxicity was CPP > PF > MCP > ACEP in all the parameters studied. PMID:17549541

  15. Tolerance to cadmium and cadmium-binding ligands in Great Salt Lake brine shrimp (Artemia salina)

    SciTech Connect

    Jayasekara, S.; Drown, D.B.; Sharma, R.P.

    1986-02-01

    Information on the accumulation of cadmium in cytosolic proteins of Great Lake brine shrimp (Artemia salina) was obtained from animals collected directly from the lake and also from animal hatched and maintained in three sublethal concentrations of cadmium (0.5, 2.0, 5.0 ppm) in saltwater aquaria. Brine shrimp growth under these conditions was monitored by measuring body lengths during a 7-day exposure period. Heat-stable, cadmium-binding ligands were isolated and identified by Sephadex G-75 chromatography and atomic absorption spectrophotometry. Cadmium was found to be equally distributed between high and low molecular weight proteins in animals collected from the lake and the 0.5 ppm cadmium group. There was also a slight growth stimulation noted in the 0.5-pm group. Higher cadmium incorporation was noted in low molecular weight fractions with increasing cadmium concentration in the exposure media. Low molecular weight fractions were also found to have high uv absorption characteristics at 250 nm and low absorption at 280 nm. Molecular weight of the cadmium-binding ligands was found to be 11,000 as estimated by the gel filtration method. De novo synthesis of this protein was increased as a function of cadmium concentration in the media. However, slow accumulation of cadmium in other protein fractions was also noticed in higher cadmium exposure groups, suggesting the existence of possible tolerance mechanisms in brine shrimp exposed to suspected acute cadmium concentrations.

  16. Biological screening of selected Pacific Northwest forest plants using the brine shrimp (Artemia salina) toxicity bioassay.

    PubMed

    Karchesy, Yvette M; Kelsey, Rick G; Constantine, George; Karchesy, Joseph J

    2016-01-01

    The brine shrimp (Artemia salina) bioassay was used to screen 211 methanol extracts from 128 species of Pacific Northwest plants in search of general cytotoxic activity. Strong toxicity (LC50 < 100 µg/ml) was found for 17 extracts from 13 species, with highest activity observed for Angelica arguta roots at <10 µg/ml. Notably, four species of cedar trees and one of juniper in the family Cupressaceae dominated this group with LC50 for heartwood extracts ranging from 15 to 89 µg/ml. Moderate toxicity (LC50 100-500 µg/ml) was found in 38 extracts from 27 species, while weak toxicity (LC50 500-1000 µg/ml) was detected for 17 extracts in 16 species. There were 139 extracts from 99 species that were non-toxic (LC50 > 1000 µg/ml). Our subsequent studies of conifer heartwoods with strong activity confirm the assay's value for identifying new investigational leads for materials with insecticidal and fungicidal activity. PMID:27186474

  17. The use of a brine shrimp (Artemia salina) bioassay to assess the toxicity of diatom extracts and short chain aldehydes.

    PubMed

    Caldwell, Gary S; Bentley, Matthew G; Olive, Peter J W

    2003-09-01

    Water soluble algal extracts, the aldehydes 2E,4E-decadienal, decanal, undecanal and the fatty acid eicosapentaenoic acid (EPA) were assayed for toxicity to hatching success and larval mortality of the brine shrimp Artemia salina. Both crude cellular extracts of the diatoms Skeletonema costatum and Nitzschia commutata and the diatom-derived short chain aldehyde decadienal were found to inhibit hatching success of A. salina cysts in a dose-dependent manner. Decadienal also significantly affected larval mortality rates in 24 and 72 h exposure incubations. The Artemia hatching success assay was the least sensitive of the three (EC50=3.94 microg ml(-1)). A greater sensitivity was observed for the 72 h compared with the 24 h exposure trials (EC50 for 24h=2.14, 72 h=0.023 microg ml(-1)). Decanal did not significantly affect survival or hatching success at the concentrations tested. Undecanal and EPA showed a limited toxic effect in naupliar mortality trials. We suggest that 72 h Artemia exposure trials represent an acceptable bioassay for diatom toxicity where alternative bioassays are unavailable. PMID:14559082

  18. Effect of temperature on post-radiation survival of Artemia salina

    SciTech Connect

    Radchenko, L.A.

    1984-01-01

    The postradiative survival rate was studied in one-day Artemia nauplii ..gamma..-irradiation in doses equal to 2.5; 5; 7.5; 10 Gy at medium temperatures of 15, 22, 25, 27/sup 0/C, respectively. A relationship is established between the irradiation effect (stimulation or inhibition) and temperature of the medium. The analysis of Artemia survival rate for stages of development shows that age contributes to the Artemia survival rate, relative to control, dependences on temperature (direct) and on the irradiation dose (inverse). 2 references, 1 figure, 2 tables.

  19. Use of Probiotic Bacillus spp. in Rotifer (Brachionus plicatilis) and Artemia (Artemia urmiana) Enrichment: Effects on Growth and Survival of Pacific White Shrimp, Litopenaeus vannamei, Larvae.

    PubMed

    Jamali, Hadi; Imani, Ahmad; Abdollahi, Daruosh; Roozbehfar, Reza; Isari, Amin

    2015-06-01

    This study was to evaluate the effect of a preparation of Bacillus probiotic (Bacillus licheniformis and B. subtilis, 1:1) on growth and survival rate of Pacific white shrimp, Litopenaeus vannamei larvae. The larvae were fed on Artemia urmiana nauplii and Brachionus plicatilis enriched with the probiotic preparation at 1 × 10(6) CFU mL(-1) rate. The experimental setup was completely randomized design comprised of six treatments, namely solo Artemia nauplii (A) or rotifer (R), Artemia nauplii and rotifer without any enrichment (A + R), Artemia nauplii enrichment with probiotic bacilli (Bacillus licheniformis and B. subtilis) (A + B), rotifer enrichment with probiotic bacilli (R + B) and enriched Artemia nauplii and rotifer (A + R + B). All treatments were performed in triplicate. Chemical parameters of rearing water viz. pH, salinity and temperature were 7.5-8, 30-31 ppt and 31-32 °C, respectively. Photoperiod was 16L:8D. Shrimp larvae were fed Artemia nauplii and rotifers at 5-20 and 10-40 individuals per shrimp larvae four times a day, respectively. Growth and survival rate of larvae were determined at MII, MIII, PL1, PL4, PL7 and PL10 stages. Larvae in A + R + B treatment showed the highest total length (10.89 ± 0.51 mm), weight (674 ± 73 μg) and survival rate (65% ± 3.5). Lowest total length, weight and survival rate (7.96 ± 0.63 mm, 493 ± 52 μg and 24.5 ± 2.4%, respectively) were recorded in treatment B larvae. We concluded that Bacillus probiotic can improve growth and survival rate of Pacific white shrimp larvae without conceivably undesirable effects.

  20. Effect of artificial regulations of Artemia n-3 HUFA content on growth and survival of black seabream ( Sparus macrocephalus) larvae

    NASA Astrophysics Data System (ADS)

    Liu, Jing-Ke

    1998-06-01

    The requirement for dietary n-3 HUFA (highly unsaturated fatty acid) for growth and survival of black seabream ( Sparus macrocephalus) larvae was tested using Artemia with various levels of n-3 HUFA. Four treatments with Artemia differing in their n-3 HUFA were prepared by feeding them various oil emulsions. The results indicated that dietary n-3 HUFA significantly influences fish n-3 HUFA levels and are necessary for good growth and survival of black seabream larvae. The proper value of n-3 HUFA level and DHA, EPA level in Artemia should be 4.273% and 0.873% (wet weight) for good growth and survival in black seabream larvae respectively.

  1. Artemia salina as a new index for assessment of acute cytotoxicity during co-composting of sewage sludge and lignocellulose waste.

    PubMed

    El Fels, Loubna; Hafidi, Mohamed; Ouhdouch, Yedir

    2016-04-01

    Considering the necessity to constantly monitor the safety of use of sewage sludge, we have focused on evaluating the toxicity of raw sludge and sludge treated by co-composting with date palm waste using an in vitro assessment of cytotoxicity based on Artemia salina larvae as a simple new sensitive and reliable routine test. The efficiency of co-composting in decreasing sludge toxicity was evaluated in terms of cytotoxicity abatement reaching 100% by the second month of composting for mixture A (1/3 sludge+2/3 date palm waste) and the third month for mixture B (1/2 sludge+1/2 date palm waste). Cytotoxicity abatement was confirmed by the increase of germination index, which reached over 100% with positive correlation for lettuce (R(2)=0.81 and 0.86) and for turnip (R(2)=0.87 and 0.74) for mixtures A and B respectively. A strong correlation between the proposed cytotoxicity test and the evolution of regulatory physical-chemical approaches was found, (R(2)=0.88 and 0.89) for NH4(+)/NO3(-) and (R(2)=0.80 and 0.88) for C/N respectively for mixture A and B. These findings allow the inexpensive bioassay reported to be used as a highly sensitive test to determine the cytotoxicity and maturity of composts. PMID:26868843

  2. Evaluation of metabolic responses of Artemia salina to oil and oil dispersant as a potential indicator of toxicant stress

    SciTech Connect

    Verriopoulos, G.; Moraitou-Apostolopoulou, M.; Xatzispirou, A.

    1986-03-01

    Oil represents an obvious hazard for the coastal environment and studies on its impact on marine organisms are necessary. Solvent based oil dispersants constitute one of the most important means for removing oil from shores. Although recently new dispersants have been developed, which are much less toxic than the first ones, dispersants still remain toxic substances. Since in the case of oil pollution treatment, oils and detergents are acting in combination, a realistic approach of laboratory studies must also include the combined action of these substances on marine organisms. Although acute toxicity studies are very useful for the determination of the range of animal tolerance, other effects causing physiological alterations may be detrimental to a population's survival. This paper concerns research on the effects of an oil, an oil dispersant and of the mixture of oil and dispersant on a physiological process, the respiration of the brine shrimp Artemia salina.

  3. Comparative study of the assay of Artemia salina L. and the estimate of the medium lethal dose (LD50 value) in mice, to determine oral acute toxicity of plant extracts.

    PubMed

    Logarto Parra, A; Silva Yhebra, R; Guerra Sardiñas, I; Iglesias Buela, L

    2001-09-01

    Artemia salina L. (Artemiidae), the brine shrimp larva, is an invertebrate used in the alternative test to determine toxicity of chemical and natural products. In this study the Medium Lethal Concentrations (LC50 value) of 20 plant extracts, Aloe vera (L.) Burm. F. (Aloeaceae), Artemisia absinthium L. (Asteraceae); Citrus aurantium L. (Rutaceae); Cymbopogon citratus (DC. Ex Nees) Stapf (Poaceae); Datura stramonium L. (Solanaceae); Justicia pectoralis Jacq. (Acanthaceae); Musa x paradisiaca L. (Musaceae); Ocimum basilicum L.; O. gratissimum L.; O. tenuiflorum L. (Lamiaceae); Pimenta dioica (L.) Merr. (Myrtaceae); Piper auritum Kunth (Piperaceae); Plantago major L. (Plantaginaceae); Plectranthus amboinicus (Lour.) Spreng. (Lamiaceae); Ruta graveolens L. (Rutaceae); Senna alata (L.) Roxb. (Fabaceae); Stachytarpheta jamaicensis (L.) Vahl (Verbenaceae); and Thuja occidentalis L. (Cupressaceae), were determined using Artemia salina L. (Artemiidae), with the objective of relating the results to the LD50 values reported in mice (tested at three concentrations: 10, 100, and 1000 microg/mL, for each extract). We found good correlation between the in vivo and the in vitro tests (r = 0.85 p < 0.05), and this method is a useful tool for predicting oral acute toxicity in plant extracts. PMID:11695884

  4. Comparative study of the assay of Artemia salina L. and the estimate of the medium lethal dose (LD50 value) in mice, to determine oral acute toxicity of plant extracts.

    PubMed

    Logarto Parra, A; Silva Yhebra, R; Guerra Sardiñas, I; Iglesias Buela, L

    2001-09-01

    Artemia salina L. (Artemiidae), the brine shrimp larva, is an invertebrate used in the alternative test to determine toxicity of chemical and natural products. In this study the Medium Lethal Concentrations (LC50 value) of 20 plant extracts, Aloe vera (L.) Burm. F. (Aloeaceae), Artemisia absinthium L. (Asteraceae); Citrus aurantium L. (Rutaceae); Cymbopogon citratus (DC. Ex Nees) Stapf (Poaceae); Datura stramonium L. (Solanaceae); Justicia pectoralis Jacq. (Acanthaceae); Musa x paradisiaca L. (Musaceae); Ocimum basilicum L.; O. gratissimum L.; O. tenuiflorum L. (Lamiaceae); Pimenta dioica (L.) Merr. (Myrtaceae); Piper auritum Kunth (Piperaceae); Plantago major L. (Plantaginaceae); Plectranthus amboinicus (Lour.) Spreng. (Lamiaceae); Ruta graveolens L. (Rutaceae); Senna alata (L.) Roxb. (Fabaceae); Stachytarpheta jamaicensis (L.) Vahl (Verbenaceae); and Thuja occidentalis L. (Cupressaceae), were determined using Artemia salina L. (Artemiidae), with the objective of relating the results to the LD50 values reported in mice (tested at three concentrations: 10, 100, and 1000 microg/mL, for each extract). We found good correlation between the in vivo and the in vitro tests (r = 0.85 p < 0.05), and this method is a useful tool for predicting oral acute toxicity in plant extracts.

  5. Toxic effects of Microgramma vacciniifolia rhizome lectin on Artemia salina, human cells, and the schistosomiasis vector Biomphalaria glabrata.

    PubMed

    de Albuquerque, Lidiane Pereira; Pontual, Emmanuel Viana; Santana, Giselly Maria de Sá; Silva, Luanna Ribeiro Santos; Aguiar, Jaciana dos Santos; Coelho, Luana Cassandra Breitenbach Barroso; Rêgo, Moacyr Jesus Barreto de Melo; Pitta, Maira Galdino da Rocha; da Silva, Teresinha Gonçalves; Melo, Ana Maria Mendonça de Albuquerque; Napoleão, Thiago Henrique; Paiva, Patrícia Maria Guedes

    2014-10-01

    The present study evaluated the toxicity of Microgramma vacciniifolia rhizome lectin (MvRL) to Artemia salina, human tumour cell lines (larynx epidermoid carcinoma Hep-2, NCI-H292 lung mucoepidermoid carcinoma, and chronic myelocytic leukaemia K562), and normal peripheral blood mononuclear cells (PBMCs), as well as to Biomphalaria glabrata embryos and adults. MvRL was toxic to A. salina (LC50=159.9 μg/mL), and exerted cytotoxic effects on NCI-H292 cells (IC50=25.23 μg/mL). The lectin (1-100 μg/mL) did not affect the viability of K562 and Hep-2 tumour cells, as well as of PBMCs. MvRL concentration of 1, 10, and 100 μg/mL promoted malformations (mainly exogastrulation) in 7.8%, 22.5%, and 27.7% of embryos, respectively, as well as delayed embryo development in 42.0%, 69.5%, and 54.7% of embryos, respectively. MvRL at a concentration of 100 μg/mL killed B. glabrata embryos (17.7%) and adults (25%). Further, MvRL damaged B. glabrata reproductive processes, which was evidenced by observations that snails exposed to the lectin (100 μg/mL) deposited fewer eggs than those in the control group, and approximately 40% of the deposited eggs exhibited malformations. Comparison of these results with that from A. salina assay indicates that MvRL is adulticidal at the concentration range which is toxic to environment. In conclusion, the cytotoxicity of MvRL on tumour cell and absence of toxicity to normal cell indicate its potential as chemotherapeutic drug. Also, the study revealed that the lectin is able to promote deleterious effects on B. glabrata embryos at environmentally safe concentrations. PMID:24954527

  6. Salinas :

    SciTech Connect

    Reese, Garth M.; Walsh, Timothy; Bhardwaj, Manoj K.

    2009-02-01

    Salinas provides a massively parallel implementation of structural dynamics nite element analysis, required for high delity, validated models used in modal, vibration, static and shock analysis of structural systems. This manual describes the theory behind many of the constructs in Salinas. For a more detailed description of how to use Salinas , we refer the reader to Salinas, Users Notes. Many of the constructs in Salinas are pulled directly from published material. Where possible, these materials are referenced herein. However, certain functions in Salinas are speci c to our implementation. We try to be far more complete in those areas. The theory manual was developed from several sources including general notes, a programmer notes manual, the user's notes and of course the material in the open literature.

  7. The ability of the branchiopod, Artemia salina, to graze upon harmful algal blooms caused by Alexandrium fundyense, Aureococcus anophagefferens, and Cochlodinium polykrikoides

    NASA Astrophysics Data System (ADS)

    Marcoval, M. Alejandra; Pan, Jerónimo; Tang, Yingzhong; Gobler, Christopher J.

    2013-10-01

    We present experiments that examined the grazing and survivorship of zooplankton native (Acartia tonsa) and non-native (Artemia salina) to NY (USA) estuaries when exposed to blooms and cultures of the three harmful algae native to NY, Alexandrium fundyense, Aureococcus anophagefferens (strains CCMP 1850 and CCMP 1984) and Cochlodinium polykrikoides. During experiments with cultures of A. anophagefferens, clearance rates (CR) of A. salina were significantly greater than those of A. tonsa for both algal strains examined. A. salina fed on cultures of C. polykrikoides at higher rates than all phytoplankton species examined, including the control diet (Rhodomonas salina), and faster than rates of A. tonsa fed C. polykrikoides. During experiments with A. fundyense, A. salina actively grazed all cell concentrations (250-1500 cells ml-1) while A. tonsa did not feed at any concentration. Percent mortality of A. salina and A. tonsa fed A. fundyense for 48 h were 43 ± 7.7% and 72 ± 7.8%, respectively, percentages significantly higher than those of individuals fed all other algal diets. During 25 field experiments using natural blooms of the three HAB species performed across six NY estuaries, A. salina significantly (p < 0.05) reduced cell densities of A. anophagefferens, C. polykrikoides, and A. fundyense relative to the control treatments in all but one experiment. The sum of these findings demonstrates that a failure to graze these HABs by the indigenous copepod, A. tonsa, may permit blooms to occur. In addition, the ability of A. salina to graze these HABs at densities that were inhibitory to A. tonsa suggests that A. salina could, in some circumstances, be considered as a part of mitigation strategy for these events.

  8. Copper(II) complexes with 2-pyridineformamide-derived thiosemicarbazones: Spectral studies and toxicity against Artemia salina

    NASA Astrophysics Data System (ADS)

    Ferraz, Karina O.; Wardell, Solange M. S. V.; Wardell, James L.; Louro, Sonia R. W.; Beraldo, Heloisa

    2009-07-01

    The copper(II) complexes [Cu(H2Am4DH)Cl 2] ( 1), [Cu(H2Am4Me)Cl 2] ( 2), [Cu(H2Am4Et)Cl 2] ( 3) and [Cu(2Am4Ph)Cl] ( 4) with 2-pyridineformamide thiosemicarbazone (H2Am4DH) and its N(4)-methyl (H2Am4Me), N(4)-ethyl (H2Am4Et) and N(4)-phenyl (H2Am4Ph) derivatives were studied by means of infrared and EPR spectral techniques. The crystal structure of 4 was determined. The studied compounds proved to be toxic to Artemia salina, suggesting that they could present cytotoxic activity against solid tumors. Among the free thiosemicarbazones H2Am4Ph presented higher toxicity than all other compounds, which showed comparable effects. In the case of complexes 2 and 3 toxicity is probably attributable to the complex as an entity or to a synergistic effect involving the thiosemicarbazone and copper. H2Am4Ph and complexes 2 and 3 revealed to be the most promising compounds as potential antineoplasic agents.

  9. Topography and stoichiometry of acidic proteins in large ribosomal subunits from Artemia salina as determined by crosslinking

    SciTech Connect

    Uchiumi, T.; Wahba, A.J.; Traut, R.R.

    1987-08-01

    The 60S subunits isolated from Artemia salina ribosomes were treated with the crosslinking reagent 2-iminothiolane under mild conditions. Proteins were extracted and fractions containing crosslinked acidic proteins were obtained by stepwise elution from CM-cellulose. Each fraction was analyzed by diagonal (two-dimensional nonreducing-reducing) NaDodSO/sub 4//polyacrylamide gel electrophoresis. Crosslinked proteins below the diagonal were radioiodinated and identified by two-dimensional acidic urea-NaDodSO/sub 4/ gel electrophoresis. Each of the acidic proteins P1 and P2 was crosslinked individually to the same third protein, PO. The fractions containing acidic proteins were also analyzed by two-dimensional nonequilibrium isoelectric focusing-NaDodSO/sub 4//polyacrylamide gel electrophoresis. Two crosslinked complexes were observed that coincide in isoelectric positions with monomeric P1 and P2, respectively. Both P1 and P2 appear to form crosslinked homodimers. These results suggest the presence in the 60S subunit of (P1)/sub 2/ and (P2)/sub 2/ dimers, each of which is anchored to PO. Protein PO appears to play the same role as L10 in Escherichia coli ribosomes and may form a pentameric complex with the two dimers in the 60S subunits.

  10. Comparing cestode infections and their consequences for host fitness in two sexual branchiopods: alien Artemia franciscana and native A. salina from syntopic-populations.

    PubMed

    Redón, Stella; Amat, Francisco; Sánchez, Marta I; Green, Andy J

    2015-01-01

    The American brine shrimp Artemia franciscana is invasive in the Mediterranean region where it has displaced native species (the sexual A. salina, and the clonal A. parthenogenetica) from many salt pond complexes. Artemia populations are parasitized by numerous avian cestodes whose effects have been studied in native species. We present a study from the Ebro Delta salterns (NE Spain), in a salt pond where both A. franciscana and native A. salina populations coexist, providing a unique opportunity to compare the parasite loads of the two sexual species in syntopy. The native species had consistently higher infection parameters, largely because the dominant cestode in A. salina adults and juveniles (Flamingolepis liguloides) was much rarer in A. franciscana. The most abundant cestodes in the alien species were Eurycestus avoceti (in adults) and Flamingolepis flamingo (in juveniles). The abundance of E. avoceti and F. liguloides was higher in the A. franciscana population syntopic with A. salina than in a population sampled at the same time in another pond where the native brine shrimp was absent, possibly because the native shrimp provides a better reservoir for parasite circulation. Infection by cestodes caused red colouration in adult and juvenile A. salina, and also led to castration in a high proportion of adult females. Both these effects were significantly stronger in the native host than in A. franciscana with the same parasite loads. However, for the first time, significant castration effects (for E. avoceti and F. liguloides) and colour change (for six cestode species) were observed in infected A. franciscana. Avian cestodes are likely to help A. franciscana outcompete native species. At the same time, they are likely to reduce the production of A. franciscana cysts in areas where they are harvested commercially. PMID:26157636

  11. Comparing cestode infections and their consequences for host fitness in two sexual branchiopods: alien Artemia franciscana and native A. salina from syntopic-populations

    PubMed Central

    Amat, Francisco; Sánchez, Marta I.; Green, Andy J.

    2015-01-01

    The American brine shrimp Artemia franciscana is invasive in the Mediterranean region where it has displaced native species (the sexual A. salina, and the clonal A. parthenogenetica) from many salt pond complexes. Artemia populations are parasitized by numerous avian cestodes whose effects have been studied in native species. We present a study from the Ebro Delta salterns (NE Spain), in a salt pond where both A. franciscana and native A. salina populations coexist, providing a unique opportunity to compare the parasite loads of the two sexual species in syntopy. The native species had consistently higher infection parameters, largely because the dominant cestode in A. salina adults and juveniles (Flamingolepis liguloides) was much rarer in A. franciscana. The most abundant cestodes in the alien species were Eurycestus avoceti (in adults) and Flamingolepis flamingo (in juveniles). The abundance of E. avoceti and F. liguloides was higher in the A. franciscana population syntopic with A. salina than in a population sampled at the same time in another pond where the native brine shrimp was absent, possibly because the native shrimp provides a better reservoir for parasite circulation. Infection by cestodes caused red colouration in adult and juvenile A. salina, and also led to castration in a high proportion of adult females. Both these effects were significantly stronger in the native host than in A. franciscana with the same parasite loads. However, for the first time, significant castration effects (for E. avoceti and F. liguloides) and colour change (for six cestode species) were observed in infected A. franciscana. Avian cestodes are likely to help A. franciscana outcompete native species. At the same time, they are likely to reduce the production of A. franciscana cysts in areas where they are harvested commercially. PMID:26157636

  12. The efficiency of a new hydrodynamic cavitation pilot system on Artemia salina cysts and natural population of copepods and bacteria under controlled mesocosm conditions.

    PubMed

    Cvetković, Martina; Grego, Mateja; Turk, Valentina

    2016-04-15

    A study of the efficiency of hydrodynamic cavitation and separation was carried out to evaluate an innovative, environmentally safe and acceptable system for ballast water treatment for reducing the risk of introducing non-native species worldwide. Mesocosm experiments were performed to assess the morphological changes and viability of zooplankton (copepods), Artemia salina cysts, and the growth potential of marine bacteria after the hydrodynamic cavitation treatment with a different number of cycles. Our preliminary results confirmed the significant efficiency of the treatment since more than 98% of the copepods and A. salina cysts were damaged, in comparison with the initial population. The efficiency increased with the number of the hydrodynamic cavitation cycles, or in combination with a separation technique for cysts. There was also a significant decrease in bacterial abundance and growth rate, compared to the initial number and growth potential. PMID:26902683

  13. Production and utilization of detyrosinated tubulin in developing Artemia larvae: evidence for a tubulin-reactive carboxypeptidase.

    PubMed

    Xiang, H; MacRae, T H

    1995-01-01

    The reversible, enzymatically driven removal and readdition of its carboxy-terminal tyrosine are major posttranslational modifications of alpha-tubulin. To study these processes isoform-specific antibodies were produced and subsequently used to characterize tyrosinated and detyrosinated tubulin in the brine shrimp, Artemia. Tyrosinated tubulin existed in relatively constant amounts on western blots of cell-free protein extracts from Artemia at all developmental stages examined, whereas detyrosinated tubulin was present after 20-24 h of postgastrula growth. In agreement with the blots, the detyrosinated isoform was observed in immunofluorescently stained larvae after 24 h of incubation, appearing first in structures of a transient nature, namely spindles and midbodies. The elongated muscle cells encircling the gut and the epithelium bordering the gut lumen were stained extensively with antibody to detyrosinated tubulin. Detyrosination was accompanied by the appearance of a tubulin-reactive carboxypeptidase, which used both nonpolymerized and polymerized tubulin as substrate. The enzyme bound to microtubules very poorly, if at all, under conditions used in this work. Several inhibitors of carboxypeptidase A had no effect on the carboxypeptidase from Artemia and revealed similarities between this enzyme and others thought to be tubulin specific. The use of inhibitors also indicated that the carboxypeptidase from Artemia recognized aspects of tubulin structure in addition to the carboxy-terminal tyrosine. Our results support the idea that detyrosinated tubulin appears in microtubules of varying stability, and they demonstrate that Artemia possess a carboxypeptidase with the potential to detyrosinate tubulin during growth of larvae. PMID:8714688

  14. Nano-sized polystyrene affects feeding, behavior and physiology of brine shrimp Artemia franciscana larvae.

    PubMed

    Bergami, Elisa; Bocci, Elena; Vannuccini, Maria Luisa; Monopoli, Marco; Salvati, Anna; Dawson, Kenneth A; Corsi, Ilaria

    2016-01-01

    Nano-sized polymers as polystyrene (PS) constitute one of the main challenges for marine ecosystems, since they can distribute along the whole water column affecting planktonic species and consequently disrupting the energy flow of marine ecosystems. Nowadays very little knowledge is available on the impact of nano-sized plastics on marine organisms. Therefore, the present study aims to evaluate the effects of 40nm anionic carboxylated (PS-COOH) and 50nm cationic amino (PS-NH2) polystyrene nanoparticles (PS NPs) on brine shrimp Artemia franciscana larvae. No signs of mortality were observed at 48h of exposure for both PS NPs at naplius stage but several sub-lethal effects were evident. PS-COOH (5-100μg/ml) resulted massively sequestered inside the gut lumen of larvae (48h) probably limiting food intake. Some of them were lately excreted as fecal pellets but not a full release was observed. Likewise, PS-NH2 (5-100µg/ml) accumulated in larvae (48h) but also adsorbed at the surface of sensorial antennules and appendages probably hampering larvae motility. In addition, larvae exposed to PS-NH2 undergo multiple molting events during 48h of exposure compared to controls. The activation of a defense mechanism based on a physiological process able to release toxic cationic NPs (PS-NH2) from the body can be hypothesized. The general observed accumulation of PS NPs within the gut during the 48h of exposure indicates a continuous bioavailability of nano-sized PS for planktonic species as well as a potential transfer along the trophic web. Therefore, nano-sized PS might be able to impair food uptake (feeding), behavior (motility) and physiology (multiple molting) of brine shrimp larvae with consequences not only at organism and population level but on the overall ecosystem based on the key role of zooplankton on marine food webs. PMID:26422775

  15. Chemical variation of essential oil constituents of Ocimum gratissimum L. from Benin, and impact on antimicrobial properties and toxicity against Artemia salina leach.

    PubMed

    Kpadonou Kpoviessi, Bénédicta G H; Ladekan, Eléonore Yayi; Kpoviessi, D S Salomé; Gbaguidi, Fernand; Yehouenou, Boniface; Quetin-Leclercq, Joëlle; Figueredo, Gilles; Moudachirou, Mansourou; Accrombessi, Georges C

    2012-01-01

    To determine the period of harvest that optimizes the antimicrobial activities of the essential oil of Ocimum gratissimum L. from Benin, aerial plant parts were collected at two vegetative stages (pre- and full-flowering) and three sampling times (7 am, 1 pm, and 7 pm). Extraction by hydrodistillation yielded between 0.65 and 0.78% of essential oils. Characterization of the oils by GC-FID and GC/MS analysis revealed the presence of monoterpenes (87.26-93.81%), sesquiterpenes (5.57-11.34%), and aliphatic compounds (0.15-0.18%), with p-cymene (1; 28.08-53.82%), thymol (2; 3.32-29.13%), γ-terpinene (3; 1.11-10.91%), α-thujene (4; 3.37-10.77%), and β-myrcene (5; 4.24-8.28%) as major components. Two chemotypes were observed, i.e., a p-cymene/thymol and a p-cymene chemotype, for plants harvested at 7 am for the former and at 1 pm or 7 pm for the latter, respectively. The oils were fungicidal against Candida albicans, with the sample from full-flowering plants collected at 7 am being the most active (MIC = 0.06±0.00 mg/ml). The chemical variation of the oils also influenced the antimicrobial effect against Staphylococcus aureus; the most active oil was obtained from plants at the pre-flowering stage collected at 7 am (MIC=0.24±0.01 mg/ml). Escherichia coli was insensitive to the chemical variation of the oils (MICs of ca. 0.48±0.02 mg/ml for all oils). Moreover, the essential oils showed low toxicity against Artemia salina Leach larvae, with LC(50) values in the range of 43-146 μg/ml. This is the first study of the interaction between the daytime of collection and vegetative stage of the plants and the antimicrobial properties and toxicity of the essential oil of O. gratissimum from Benin. PMID:22253111

  16. Evaluation of toxic, cytotoxic, mutagenic, and antimutagenic activities of natural and technical cashew nut shell liquids using the Allium cepa and Artemia salina bioassays.

    PubMed

    Leite, Aracelli de Sousa; Dantas, Alisson Ferreira; Oliveira, George Laylson da Silva; Gomes Júnior, Antonio L; de Lima, Sidney Gonçalo; Citó, Antônia Maria das Graças Lopes; de Freitas, Rivelilson M; Melo-Cavalcante, Ana Amélia de C; Dantas Lopes, José Arimateia

    2015-01-01

    The cashew nut releases a substance that is known as cashew nut shell liquid (CNSL). There are both natural (iCNSL) and technical (tCNSL) cashew nut shell liquids. This study used an Artemia salina bioassay to evaluate the toxic effects of iCNSL and tCNSL cashew nut shell liquids. It also evaluated the toxicity, cytotoxicity, and mutagenicity of CNSL and its effects on the damage induced by copper sulfate (CuSO4·5H2O) on the meristems' root of Allium cepa. Effects of the damage induced by CuSO4·5H2O were evaluated before (pre-), during (co-), and after (post-) treatments. The iCNSL contained 94.5% anacardic acid, and the tCNSL contained 91.3% cardanol. The liquids were toxic to A. salina. Toxicity, cytotoxicity, and mutagenicity were observed with iCNSL compared with the negative control. Similarly, iCNSL failed to inhibit the toxicity and cytotoxicity of CuSO4·5H2O. The tCNSL was not toxic, cytotoxic, or mutagenic in any of the concentrations. However, the lowest iCNSL concentrations and all of the tCNSL concentrations had preventive, antimutagenic, and reparative effects on micronuclei and on chromosomal aberrations in the A. cepa. Therefore, protective, modulating, and reparative effects may be observed in the A. cepa, depending on the concentration and type of CNSL used. PMID:25861638

  17. Evaluation of toxic, cytotoxic, mutagenic, and antimutagenic activities of natural and technical cashew nut shell liquids using the Allium cepa and Artemia salina bioassays.

    PubMed

    Leite, Aracelli de Sousa; Dantas, Alisson Ferreira; Oliveira, George Laylson da Silva; Gomes Júnior, Antonio L; de Lima, Sidney Gonçalo; Citó, Antônia Maria das Graças Lopes; de Freitas, Rivelilson M; Melo-Cavalcante, Ana Amélia de C; Dantas Lopes, José Arimateia

    2015-01-01

    The cashew nut releases a substance that is known as cashew nut shell liquid (CNSL). There are both natural (iCNSL) and technical (tCNSL) cashew nut shell liquids. This study used an Artemia salina bioassay to evaluate the toxic effects of iCNSL and tCNSL cashew nut shell liquids. It also evaluated the toxicity, cytotoxicity, and mutagenicity of CNSL and its effects on the damage induced by copper sulfate (CuSO4·5H2O) on the meristems' root of Allium cepa. Effects of the damage induced by CuSO4·5H2O were evaluated before (pre-), during (co-), and after (post-) treatments. The iCNSL contained 94.5% anacardic acid, and the tCNSL contained 91.3% cardanol. The liquids were toxic to A. salina. Toxicity, cytotoxicity, and mutagenicity were observed with iCNSL compared with the negative control. Similarly, iCNSL failed to inhibit the toxicity and cytotoxicity of CuSO4·5H2O. The tCNSL was not toxic, cytotoxic, or mutagenic in any of the concentrations. However, the lowest iCNSL concentrations and all of the tCNSL concentrations had preventive, antimutagenic, and reparative effects on micronuclei and on chromosomal aberrations in the A. cepa. Therefore, protective, modulating, and reparative effects may be observed in the A. cepa, depending on the concentration and type of CNSL used.

  18. Evaluation of Toxic, Cytotoxic, Mutagenic, and Antimutagenic Activities of Natural and Technical Cashew Nut Shell Liquids Using the Allium cepa and Artemia salina Bioassays

    PubMed Central

    Leite, Aracelli de Sousa; Oliveira, George Laylson da Silva; Gomes Júnior, Antonio L.; de Lima, Sidney Gonçalo; Citó, Antônia Maria das Graças Lopes; de Freitas, Rivelilson M.; Melo-Cavalcante, Ana Amélia de C.; Dantas Lopes, José Arimateia

    2015-01-01

    The cashew nut releases a substance that is known as cashew nut shell liquid (CNSL). There are both natural (iCNSL) and technical (tCNSL) cashew nut shell liquids. This study used an Artemia salina bioassay to evaluate the toxic effects of iCNSL and tCNSL cashew nut shell liquids. It also evaluated the toxicity, cytotoxicity, and mutagenicity of CNSL and its effects on the damage induced by copper sulfate (CuSO4·5H2O) on the meristems' root of Allium cepa. Effects of the damage induced by CuSO4·5H2O were evaluated before (pre-), during (co-), and after (post-) treatments. The iCNSL contained 94.5% anacardic acid, and the tCNSL contained 91.3% cardanol. The liquids were toxic to A. salina. Toxicity, cytotoxicity, and mutagenicity were observed with iCNSL compared with the negative control. Similarly, iCNSL failed to inhibit the toxicity and cytotoxicity of CuSO4·5H2O. The tCNSL was not toxic, cytotoxic, or mutagenic in any of the concentrations. However, the lowest iCNSL concentrations and all of the tCNSL concentrations had preventive, antimutagenic, and reparative effects on micronuclei and on chromosomal aberrations in the A. cepa. Therefore, protective, modulating, and reparative effects may be observed in the A. cepa, depending on the concentration and type of CNSL used. PMID:25861638

  19. Fusaproliferin production by Fusarium subglutinans and its toxicity to Artemia salina, SF-9 insect cells, and IARC/LCL 171 human B lymphocytes.

    PubMed Central

    Logrieco, A; Moretti, A; Fornelli, F; Fogliano, V; Ritieni, A; Caiaffa, M F; Randazzo, G; Bottalico, A; Macchia, L

    1996-01-01

    Fusarium subglutinans is an important pathogen of maize and other commodities worldwide. We examined MRC-115 and 71 other F. subglutinans strains from various geographic areas for their ability to synthesize fusaproliferin, a novel toxic sesterterpene recently isolated from F. proliferatum. Fusaproliferin production ranged from 30 to 1,500 micrograms/g of dried ground substrate, with 33 strains producing more than 500 micrograms/g. In particular, strain MRC-115 produced as much as 1,100 to 1,300 micrograms/g. In toxicity studies of two invertebrate models, fusaproliferin was toxic to Artemia salina (50% lethal dose, 53.4 microM) and to the lepidopteran cell line SF-9 (50% cytotoxic concentration, approximately 70 microM, after a 48-h exposure). Fusaproliferin was also toxic to the human nonneoplastic B-lymphocyte cell line IARC/LCL 171 (50% cytotoxic concentration, approximately 55 microM in culture in stationary phase after a 48-h exposure). Experiments performed will cells exposed at seeding suggested a possible cytostatic effect at subtoxic concentrations. PMID:8795229

  20. Proteomic analysis of acute responses to copper sulfate stress in larvae of the brine shrimp, Artemia sinica

    NASA Astrophysics Data System (ADS)

    Zhou, Qian; Wu, Changgong; Dong, Bo; Li, Fuhua; Liu, Fengqi; Xiang, Jianhai

    2010-03-01

    Proteomics was used to reveal the differential protein expression profiles of acute responses to copper sulfate exposure in larvae of Artemia sinica. Fourteen differentially displayed protein spots were detected and seven of them were identified. Three spots were up-expressed and identified: actin, heat shock protein 70, and chaperone subunit 1; three down-regulated proteins were identified: arginine kinase, elongation factor-2, and glycine-rich protein; and a newly expressed protein was identified as peroxiredoxin. The study indicates the involvement of all the differentially expressed proteins in the early responses of protein expression, and in the survival of A. sinica in the presence of copper and other heavy metals; the findings improve understanding of the organism’s adaptive responses and resistance.

  1. Studies on the structure and biosynthesis of the linkage region between chitin and protein in Artemia salina

    SciTech Connect

    Horst, M.N.

    1986-05-01

    In vivo and in vitro studies on chitin synthesis in Artemia nauplii indicate that two classes of /sup 3/H GlcNAc labeled products are synthesized. The first is soluble in urea and contains a chitoprotein with short chitin oligosaccharides and attached to a high molecular weight polypeptide. The other product is insoluble in urea and SDS, and contains crosslinked, macromolecular chitin. Both classes of chitin products bind the fluorescent probe Calcofluor White (CW), as do glycopeptides prepared from these samples by pronase digestion. The in vivo and in vitro effect of CW on synthesis of both chitin products has been examined. /sup 3/H GlcNAc-labeled glycopeptides have been generated from both products by HCl partial hydrolysis, CNBr cleavage or pronase digestion. Analysis of the pronase soluble fraction after digestion of the urea residue has been carried out by gel permeation and paper chromatography. Sic glycopeptide fractions have been isolated which contain up to 85% (w/w) GlcN and 4-6 predominant amino acids. Common amino acids in all fractions are Asp, Arg and Thr; others found include Lys, Glu and Ala. Synthesis of /sup 3/H GlcNAc-labeled chitopeptides has been achieved in vitro using artificial peptide acceptors such as DNS-Ala-Ile-Glu-Asn-Ala-Thr-Leu and N/sup ..cap alpha../-/sup 3/H Ac-Asn-Tyr-Thr-NHCH/sub 3/. Further studies on the synthesis of Dol-PP-(GlcNAc)/sub 3-8/ and the properties of the oligosaccharide transferase are in progress.

  2. The effect of juvenile hormone III, methyl farnesoate, and methoprene on Na/K-ATPase activity in larvae of the brine shrimp, Artemia.

    PubMed

    Ahl, J S; Brown, J J

    1991-01-01

    1. Ion transport enzyme (Na/K-ATPase) activity in stage III larvae of the brine shrimp, Artemia, remains elevated throughout the stadium when populations are exposed to methoprene in artificial seawater. 2. Infusion of methoprene, juvenile hormone, or methyl farnesoate causes increased Na/K-ATPase activity in homogenates of mid-stadium larvae that would otherwise exhibit low activity. 3. The sensitivity of the enzyme system to extremely low concentrations of the juvenoids suggests that this may be a common mode of action of these compounds. Additionally it suggests that the enzyme may be under the influence of a similar compound present in the larvae. PMID:1682091

  3. Portuguese native Artemia parthenogenetica resisting invasion by Artemia franciscana - Assessing reproductive parameters under different environmental conditions

    NASA Astrophysics Data System (ADS)

    Pinto, Pedro M.; Hontoria, Francisco; Vieira, Natividade; Bio, Ana

    2014-05-01

    There is widespread interest in the conservation of native Artemia biodiversity. In Portugal, only two known populations of native Artemia remain: one in the Rio Maior salina, the other in the Aveiro salina complex, both of the diploid Artemia parthenogenetica species. All other Portuguese hypersaline environments where Artemia can be found have been invaded by Artemia franciscana, which has eradicated the native strains. Invasiveness and resilience of, respectively, exotic and indigenous species are thought to depend on strain-specific traits and adaptation to local conditions. This work evaluates the reproductive performance of the two Portuguese native strains and the invasive species exposed to different salinities, temperatures, photoperiods and food supplies. Reproduction periods, quantity and quality of offspring varied significantly, depending on both the Artemia strain and environmental conditions. A. parthenogenetica from Rio Maior reproduced better than A. franciscana at high salinity (150) and low food supply, which may reflect an adaptation to its biotope that aids its resistance to invasion. But A. parthenogenetica form Aveiro performed much worse than its invasive competitor, under most of the conditions tested. It is unlikely that A. franciscana has not been introduced in this salina by chance alone. Other biological traits of the local A. parthenogenetica or adaptation to unstudied local factors (e.g. pollution) are probably responsible for this strain's survival. Further knowledge on specific local conditions and trait-specific tolerances to biotic and abiotic conditions are needed to understand (non-)invasion patterns and preserve the remaining native populations.

  4. Bacillus sp. LT3 improves the survival of gnotobiotic brine shrimp (Artemia franciscana) larvae challenged with Vibrio campbellii by enhancing the innate immune response and by decreasing the activity of shrimp-associated vibrios.

    PubMed

    Niu, Yufeng; Defoirdt, Tom; Baruah, Kartik; Van de Wiele, Tom; Dong, Shuanglin; Bossier, Peter

    2014-10-10

    Bacteria belonging to the genus Bacillus are amongst the most intensively studied group of bacteria for use as probiotics in aquaculture. However, the exact mechanism of action of these bacteria is often not well described, and the microbiota that are naturally present in cultures of test organisms often compromise the interpretation of the results. The present study aimed to evaluate the putative probiotic effect of Bacillus sp. LT3 in a model system with gnotobiotic brine shrimp Artemia franciscana larvae. The strain significantly increased the survival of brine shrimp larvae challenged with Vibrio campbellii when administered 6h before the challenge. Under these conditions, LT3 was able to colonize the brine shrimp gastrointestinal tract and to decrease the in vivo pathogen activity as indicated by the bioluminescence of the V. campbellii associated with brine shrimp larvae. In order to investigate the effect of the Bacillus strain on the innate immune system of the brine shrimp larvae, prophenoloxidase and transglutaminase mRNA levels were monitored, while heat shock protein 70 mRNA levels were measured as an indicator of physiological stress. Interestingly, 12h after challenge, the prophenoloxidase mRNA level in the larvae pre-treated with LT3 and challenged with V. campbellii was approximately 8-fold higher than in the other treatments. Further, a decreased mRNA level of transglutaminase gene and heat shock protein 70 gene suggested that pretreatment with LT3 results in less stress and tissue damage in the brine shrimp larvae upon V. campbellii challenge. These results indicated that Bacillus sp. LT3 could improve the survival of brine shrimp larvae when challenged with pathogenic V. campbellii, both by decreasing the in vivo activity of the pathogen and by priming the innate immune response through activating the prophenoloxidase system.

  5. Bacillus sp. LT3 improves the survival of gnotobiotic brine shrimp (Artemia franciscana) larvae challenged with Vibrio campbellii by enhancing the innate immune response and by decreasing the activity of shrimp-associated vibrios.

    PubMed

    Niu, Yufeng; Defoirdt, Tom; Baruah, Kartik; Van de Wiele, Tom; Dong, Shuanglin; Bossier, Peter

    2014-10-10

    Bacteria belonging to the genus Bacillus are amongst the most intensively studied group of bacteria for use as probiotics in aquaculture. However, the exact mechanism of action of these bacteria is often not well described, and the microbiota that are naturally present in cultures of test organisms often compromise the interpretation of the results. The present study aimed to evaluate the putative probiotic effect of Bacillus sp. LT3 in a model system with gnotobiotic brine shrimp Artemia franciscana larvae. The strain significantly increased the survival of brine shrimp larvae challenged with Vibrio campbellii when administered 6h before the challenge. Under these conditions, LT3 was able to colonize the brine shrimp gastrointestinal tract and to decrease the in vivo pathogen activity as indicated by the bioluminescence of the V. campbellii associated with brine shrimp larvae. In order to investigate the effect of the Bacillus strain on the innate immune system of the brine shrimp larvae, prophenoloxidase and transglutaminase mRNA levels were monitored, while heat shock protein 70 mRNA levels were measured as an indicator of physiological stress. Interestingly, 12h after challenge, the prophenoloxidase mRNA level in the larvae pre-treated with LT3 and challenged with V. campbellii was approximately 8-fold higher than in the other treatments. Further, a decreased mRNA level of transglutaminase gene and heat shock protein 70 gene suggested that pretreatment with LT3 results in less stress and tissue damage in the brine shrimp larvae upon V. campbellii challenge. These results indicated that Bacillus sp. LT3 could improve the survival of brine shrimp larvae when challenged with pathogenic V. campbellii, both by decreasing the in vivo activity of the pathogen and by priming the innate immune response through activating the prophenoloxidase system. PMID:25190276

  6. Schinus terebinthifolius Leaf Extract Causes Midgut Damage, Interfering with Survival and Development of Aedes aegypti Larvae.

    PubMed

    Procópio, Thamara Figueiredo; Fernandes, Kenner Morais; Pontual, Emmanuel Viana; Ximenes, Rafael Matos; de Oliveira, Aline Rafaella Cardoso; Souza, Carolina de Santana; Melo, Ana Maria Mendonça de Albuquerque; Navarro, Daniela Maria do Amaral Ferraz; Paiva, Patrícia Maria Guedes; Martins, Gustavo Ferreira; Napoleão, Thiago Henrique

    2015-01-01

    In this study, a leaf extract from Schinus terebinthifolius was evaluated for effects on survival, development, and midgut of A. aegypti fourth instar larvae (L4), as well as for toxic effect on Artemia salina. Leaf extract was obtained using 0.15 M NaCl and evaluated for phytochemical composition and lectin activity. Early L4 larvae were incubated with the extract (0.3-1.35%, w/v) for 8 days, in presence or absence of food. Polymeric proanthocyanidins, hydrolysable tannins, heterosid and aglycone flavonoids, cinnamic acid derivatives, traces of steroids, and lectin activity were detected in the extract, which killed the larvae at an LC50 of 0.62% (unfed larvae) and 1.03% (fed larvae). Further, the larvae incubated with the extract reacted by eliminating the gut content. No larvae reached the pupal stage in treatments at concentrations between 0.5% and 1.35%, while in the control (fed larvae), 61.7% of individuals emerged as adults. The extract (1.0%) promoted intense disorganization of larval midgut epithelium, including deformation and hypertrophy of cells, disruption of microvilli, and vacuolization of cytoplasms, affecting digestive, enteroendocrine, regenerative, and proliferating cells. In addition, cells with fragmented DNA were observed. Separation of extract components by solid phase extraction revealed that cinnamic acid derivatives and flavonoids are involved in larvicidal effect of the extract, being the first most efficient in a short time after larvae treatment. The lectin present in the extract was isolated, but did not show deleterious effects on larvae. The extract and cinnamic acid derivatives were toxic to A. salina nauplii, while the flavonoids showed low toxicity. S. terebinthifolius leaf extract caused damage to the midgut of A. aegypti larvae, interfering with survival and development. The larvicidal effect of the extract can be attributed to cinnamic acid derivatives and flavonoids. The data obtained using A. salina indicates that caution

  7. Schinus terebinthifolius Leaf Extract Causes Midgut Damage, Interfering with Survival and Development of Aedes aegypti Larvae

    PubMed Central

    Procópio, Thamara Figueiredo; Fernandes, Kenner Morais; Pontual, Emmanuel Viana; Ximenes, Rafael Matos; de Oliveira, Aline Rafaella Cardoso; Souza, Carolina de Santana; Melo, Ana Maria Mendonça de Albuquerque; Navarro, Daniela Maria do Amaral Ferraz; Paiva, Patrícia Maria Guedes; Martins, Gustavo Ferreira; Napoleão, Thiago Henrique

    2015-01-01

    In this study, a leaf extract from Schinus terebinthifolius was evaluated for effects on survival, development, and midgut of A. aegypti fourth instar larvae (L4), as well as for toxic effect on Artemia salina. Leaf extract was obtained using 0.15 M NaCl and evaluated for phytochemical composition and lectin activity. Early L4 larvae were incubated with the extract (0.3–1.35%, w/v) for 8 days, in presence or absence of food. Polymeric proanthocyanidins, hydrolysable tannins, heterosid and aglycone flavonoids, cinnamic acid derivatives, traces of steroids, and lectin activity were detected in the extract, which killed the larvae at an LC50 of 0.62% (unfed larvae) and 1.03% (fed larvae). Further, the larvae incubated with the extract reacted by eliminating the gut content. No larvae reached the pupal stage in treatments at concentrations between 0.5% and 1.35%, while in the control (fed larvae), 61.7% of individuals emerged as adults. The extract (1.0%) promoted intense disorganization of larval midgut epithelium, including deformation and hypertrophy of cells, disruption of microvilli, and vacuolization of cytoplasms, affecting digestive, enteroendocrine, regenerative, and proliferating cells. In addition, cells with fragmented DNA were observed. Separation of extract components by solid phase extraction revealed that cinnamic acid derivatives and flavonoids are involved in larvicidal effect of the extract, being the first most efficient in a short time after larvae treatment. The lectin present in the extract was isolated, but did not show deleterious effects on larvae. The extract and cinnamic acid derivatives were toxic to A. salina nauplii, while the flavonoids showed low toxicity. S. terebinthifolius leaf extract caused damage to the midgut of A. aegypti larvae, interfering with survival and development. The larvicidal effect of the extract can be attributed to cinnamic acid derivatives and flavonoids. The data obtained using A. salina indicates that caution

  8. Salinas primer.

    SciTech Connect

    Walsh, Timothy Francis; Reese, Garth M.; Bhardwaj, Manoj Kumar

    2004-08-01

    Salinas provides a massively parallel implementation of structural dynamics finite element analysis. This capability is required for high fidelity, validated models used in modal, vibration, static and shock analysis of weapons systems. General capabilities for modal, statics and transient dynamics are provided. Salinas is similar to commercial codes like Nastran or Abaqus. It has some nonlinear capability, but excels in linear computation. It is different than the above commercial codes in that it is designed to operate efficiently in a massively parallel environment. Even for an experienced analyst, running a new finite element package can be a challenge. This little primer is intended to make part of this task easier by presenting the basic steps in a simple way. The analyst is referred to the theory manual for details of the mathematics behind the work. The User's Notes should be used for more complex inputs, and will have more details about the process (as well as many more examples). More information can be found on our web pages, 3 or 4. Finite element analysis can be deceptive. Any software can give the wrong answers if used improperly, and occasionally even when used properly. Certainly a solid background in structural mechanics is necessary to build an adequate finite element model and interpret the results. This primer should provide a quick start in answering some of the more common questions that come up in using Salinas.

  9. Salinas : theory manual.

    SciTech Connect

    Walsh, Timothy Francis; Reese, Garth M.; Bhardwaj, Manoj Kumar

    2004-08-01

    This manual describes the theory behind many of the constructs in Salinas. For a more detailed description of how to use Salinas , we refer the reader to Salinas, User's Notes. Many of the constructs in Salinas are pulled directly from published material. Where possible, these materials are referenced herein. However, certain functions in Salinas are specific to our implementation. We try to be far more complete in those areas. The theory manual was developed from several sources including general notes, a programer-notes manual, the user's notes and of course the material in the open literature.

  10. Salinas : theory manual.

    SciTech Connect

    Walsh, Timothy Francis; Reese, Garth M.; Bhardwaj, Manoj Kumar

    2011-11-01

    Salinas provides a massively parallel implementation of structural dynamics finite element analysis, required for high fidelity, validated models used in modal, vibration, static and shock analysis of structural systems. This manual describes the theory behind many of the constructs in Salinas. For a more detailed description of how to use Salinas, we refer the reader to Salinas, User's Notes. Many of the constructs in Salinas are pulled directly from published material. Where possible, these materials are referenced herein. However, certain functions in Salinas are specific to our implementation. We try to be far more complete in those areas. The theory manual was developed from several sources including general notes, a programmer notes manual, the user's notes and of course the material in the open literature.

  11. Radiation Damage to Artemia Cysts:Effects of Water Vapor.

    PubMed

    Snipes, W C; Gordy, W

    1963-10-25

    Water vapor altered the form and greatly increased the rate of decay of the electron-spin resonance pattern of long-lived free radicals obtained upon gamma irradiation of Artemia salina cysts ( brine shrimp eggs). These results, combined with data on radiation survival, indicate that the water vapor protects the cysts from radiation damage, or heals the damage. They also indicate that water protects the cysts from the effect of oxygen by neutralizing the radiation-induced free radicals before they can interact with oxygen to produce irreversible damage. PMID:17748168

  12. Salinas - User's Notes

    SciTech Connect

    ALVIN,KENNETH F.; BHARDWAJ,MANOJ K.; DRIESSEN,BRIAN; REESE,GARTH M.; SEGALMAN,DANIEL J.

    1999-11-01

    Salinas provides a massively parallel implementation of structural dynamics finite element analysis, required for high fidelity, validated models used in modal, vibration, static and shock analysis of weapons systems. This document provides a users guide to the input for Salinas. Details of input specifications for the different solution types, output options, element types and parameters are included. The appendices contain detailed examples, and instructions for running the software on parallel platforms.

  13. High prevalence of cestodes in Artemia spp. throughout the annual cycle: relationship with abundance of avian final hosts

    USGS Publications Warehouse

    Sánchez, Marta I.; Nikolov, Pavel N.; GEorgieva, Darina D.; Georgiev, Boyko B.; Vasileva, Gergana P.; Pankov, Plamen; Paracuellos, Mariano; Lafferty, Kevin D.; Green, Andy J.

    2013-01-01

    Brine shrimp, Artemia spp., act as intermediate hosts for a range of cestode species that use waterbirds as their final hosts. These parasites can have marked influences on shrimp behavior and fecundity, generating the potential for cascading effects in hypersaline food webs. We present the first comprehensive study of the temporal dynamics of cestode parasites in natural populations of brine shrimp throughout the annual cycle. Over a 12-month period, clonal Artemia parthenogenetica were sampled in the Odiel marshes in Huelva, and the sexual Artemia salina was sampled in the Salinas de Cerrillos in Almería. Throughout the year, 4–45 % of A. parthenogenetica were infected with cestodes (mean species richness = 0.26), compared to 27–72 % of A. salina (mean species richness = 0.64). Ten cestode species were recorded. Male and female A. salina showed similar levels of parasitism. The most prevalent and abundant cestodes were those infecting the most abundant final hosts, especially the Greater Flamingo Phoenicopterus ruber. In particular, the flamingo parasite Flamingolepis liguloides had a prevalence of up to 43 % in A. parthenogenetica and 63.5 % in A. salina in a given month. Although there was strong seasonal variation in prevalence, abundance, and intensity of cestode infections, seasonal changes in bird counts were weak predictors of the dynamics of cestode infections. However, infection levels of Confluaria podicipina in A. parthenogenetica were positively correlated with the number of their black-necked grebe Podiceps nigricollis hosts. Similarly, infection levels of Anomotaenia tringae and Anomotaenia microphallos in A. salina were correlated with the number of shorebird hosts present the month before. Correlated seasonal transmission structured the cestode community, leading to more multiple infections than expected by chance.

  14. High prevalence of cestodes in Artemia spp. throughout the annual cycle: relationship with abundance of avian final hosts.

    PubMed

    Sánchez, Marta I; Nikolov, Pavel N; Georgieva, Darina D; Georgiev, Boyko B; Vasileva, Gergana P; Pankov, Plamen; Paracuellos, Mariano; Lafferty, Kevin D; Green, Andy J

    2013-05-01

    Brine shrimp, Artemia spp., act as intermediate hosts for a range of cestode species that use waterbirds as their final hosts. These parasites can have marked influences on shrimp behavior and fecundity, generating the potential for cascading effects in hypersaline food webs. We present the first comprehensive study of the temporal dynamics of cestode parasites in natural populations of brine shrimp throughout the annual cycle. Over a 12-month period, clonal Artemia parthenogenetica were sampled in the Odiel marshes in Huelva, and the sexual Artemia salina was sampled in the Salinas de Cerrillos in Almería. Throughout the year, 4-45 % of A. parthenogenetica were infected with cestodes (mean species richness = 0.26), compared to 27-72 % of A. salina (mean species richness = 0.64). Ten cestode species were recorded. Male and female A. salina showed similar levels of parasitism. The most prevalent and abundant cestodes were those infecting the most abundant final hosts, especially the Greater Flamingo Phoenicopterus ruber. In particular, the flamingo parasite Flamingolepis liguloides had a prevalence of up to 43 % in A. parthenogenetica and 63.5 % in A. salina in a given month. Although there was strong seasonal variation in prevalence, abundance, and intensity of cestode infections, seasonal changes in bird counts were weak predictors of the dynamics of cestode infections. However, infection levels of Confluaria podicipina in A. parthenogenetica were positively correlated with the number of their black-necked grebe Podiceps nigricollis hosts. Similarly, infection levels of Anomotaenia tringae and Anomotaenia microphallos in A. salina were correlated with the number of shorebird hosts present the month before. Correlated seasonal transmission structured the cestode community, leading to more multiple infections than expected by chance. PMID:23463137

  15. SALINAS1.0

    SciTech Connect

    Reese, Garth; Bhardwaj, Manoj; Pierson, Kendall; Walsh, Tim; Day, David

    2002-10-01

    Salinas isa general purpose finite element package for structural dynamics analysis, written pecifically for distributed memory computers. It has been used for the analysis of structures ranging MEMs, to weapons components to aircraft carriers. The package provides eigenanalysis, and implicit linear and nonlinear transient and static analysis of structures, and incorporates sensitivity analysis. A full range of structural elements is provided.

  16. Embryogenesis, hatching and larval development of Artemia during orbital spaceflight

    NASA Technical Reports Server (NTRS)

    Spooner, B. S.; Debell, L.; Armbrust, L.; Guikema, J. A.; Metcalf, J.; Paulsen, A.

    1994-01-01

    Developmental biology studies, using gastrula-arrested cysts of the brine shrimp Artemia franciscana, were conducted during two flights of the space shuttle Atlantis (missions STS-37 and STS-43) in 1991. Dehydrated cysts were activated, on orbit, by addition of salt water to the cysts, and then development was terminated by the addition of fixative. Development took place in 5 ml syringes, connected by tubing to activation syringes, containing salt water, and termination syringes, containing fixative. Comparison of space results with simultaneous ground control experiments showed that equivalent percentages of naupliar larvae hatched in the syringes (40%). Thus, reactivation of development, completion of embryogenesis, emergence and hatching took place, during spaceflight, without recognizable alteration in numbers of larvae produced. Post-hatching larval development was studied in experiments where development was terminated, by introduction of fixative, 2 days, 4 days, and 8 days after reinitiation of development. During spaceflight, successive larval instars or stages, interrupted by molts, occurred, generating brine shrimp at appropriate larval instars. Naupliar larvae possessed the single naupliar eye, and development of the lateral pair of adult eyes also took place in space. Transmission electron microscopy revealed extensive differentiation, including skeletal muscle and gut endoderm, as well as the eye tissues. These studies demonstrate the potential value of Artemia for developmental biology studies during spa ceflight, and show that extensive degrees of development can take place in this microgravity environment.

  17. Embryogenesis, hatching and larval development of Artemia during orbital spaceflight

    NASA Astrophysics Data System (ADS)

    Spooner, B. S.; Debell, L.; Armbrust, L.; Guikema, J. A.; Metcalf, J.; Paulsen, A.

    1994-08-01

    Developmental biology studies, using gastrula-arrested cysts of the brine shrimp Artemia franciscana, were conducted during two flights of the space shuttle Atlantis (missions STS-37 and STS-43) in 1991. Dehydrated cysts were activated, on orbit, by addition of salt water to the cysts, and then development was terminated by the addition of fixative. Development took place in 5 ml syringes, connected by tubing to activation syringes, containing salt water, and termination syringes, containing fixative. Comparison of space results with simultaneous ground control experiments showed that equivalent percentages of naupliar larvae hatched in the syringes (40%). Thus, reactivation of development, completion of embryogenesis, emergence and hatching took place, during spaceflight, without recognizable alteration in numbers of larvae produced. Post-hatching larval development was studied in experiments where development was terminated, by intrduction of fixative, 2 days, 4 days, and 8 days after reinitiation of development. During spaceflight, successive larval instars or stages, interrupted by molts, occurred, generating brine shrimp at appropriate larval instars. Naupliar larvae possessed the single naupliar eye, and development of the lateral pair of adult eyes also took place in space. Transmission electron microscopy revealed extensive differentiation, including skeletal muscle and gut endoderm, as well as the eye tissues. These studies demonstrate the potential value of Artemia for developmental biology studies during spaceflight, and show that extensive degress of development can take place in this microgravity environment.

  18. Molecular cloning and expression analysis of the retinoid X receptor (RXR) gene in golden pompano Trachinotus ovatus fed Artemia nauplii with different enrichments.

    PubMed

    Yang, Qibin; Zheng, Panlong; Ma, Zhenhua; Li, Tao; Jiang, Shigui; Qin, Jian G

    2015-12-01

    The retinoid X receptors (RXRs) are involved in the skeletal development and other biological process such as blood vessel formation and metabolism. Partial sequences of RXRα and β genes were obtained, and their expressions were quantified on golden pompano Trachinotus ovatus at 28 days post hatching (DPH) to explore the molecular response to nutritional manipulation in fish larvae. As live food, Artemia nauplii were separately enriched with Nannochloropsis and Algamac 3080 and non-enriched Artemia nauplii (control) for fish feeding. The expressions of RXRs were detected in the embryos and fish larvae at early stages, suggesting that the skeletal development in golden pompano initiated before yolk re-sorption completion. Fish fed non-enriched Artemia nauplii ended up with higher jaw malformation. The highest specific growth rate was obtained when fish were fed with the Artemia nauplii enriched with Algamac 3080, and the lowest growth rate was observed when fish were fed with unenriched Artemia nauplii. The highest survival was obtained when fish were fed with non-enriched or Nannochloropsis-enriched Artemia nauplii. This study indicates that the use of enriched formula for Artemia nauplii can significantly affect the expression levels of RXRs and jaw malformation of golden pompano larvae, but there is no clear correlation between RXRs expressions and malformation rates when fish are subjected to nutrient challenge. PMID:26159320

  19. Molecular cloning and expression analysis of the retinoid X receptor (RXR) gene in golden pompano Trachinotus ovatus fed Artemia nauplii with different enrichments.

    PubMed

    Yang, Qibin; Zheng, Panlong; Ma, Zhenhua; Li, Tao; Jiang, Shigui; Qin, Jian G

    2015-12-01

    The retinoid X receptors (RXRs) are involved in the skeletal development and other biological process such as blood vessel formation and metabolism. Partial sequences of RXRα and β genes were obtained, and their expressions were quantified on golden pompano Trachinotus ovatus at 28 days post hatching (DPH) to explore the molecular response to nutritional manipulation in fish larvae. As live food, Artemia nauplii were separately enriched with Nannochloropsis and Algamac 3080 and non-enriched Artemia nauplii (control) for fish feeding. The expressions of RXRs were detected in the embryos and fish larvae at early stages, suggesting that the skeletal development in golden pompano initiated before yolk re-sorption completion. Fish fed non-enriched Artemia nauplii ended up with higher jaw malformation. The highest specific growth rate was obtained when fish were fed with the Artemia nauplii enriched with Algamac 3080, and the lowest growth rate was observed when fish were fed with unenriched Artemia nauplii. The highest survival was obtained when fish were fed with non-enriched or Nannochloropsis-enriched Artemia nauplii. This study indicates that the use of enriched formula for Artemia nauplii can significantly affect the expression levels of RXRs and jaw malformation of golden pompano larvae, but there is no clear correlation between RXRs expressions and malformation rates when fish are subjected to nutrient challenge.

  20. Determination of biological and physicochemical parameters of Artemia franciscana strains in hypersaline environments for aquaculture in the Colombian Caribbean

    PubMed Central

    Camargo, William N; Durán, Gabriel C; Rada, Orlando C; Hernández, Licet C; Linero, Juan-Carlos G; Muelle, Igor M; Sorgeloos, Patrick

    2005-01-01

    Background Artemia (Crustacea, Anostraca), also known as brine shrimp, are typical inhabitants of extreme environments. These hypersaline environments vary considerably in their physicochemical composition, and even their climatic conditions and elevation. Several thalassohaline (marine) environments along the Colombian Caribbean coast were surveyed in order to contribute to the knowledge of brine shrimp biotopes in South America by determining some vital biological and physicochemical parameters for Artemia survival. Additionally, cyst quality tests, biometrical and essential fatty acids analysis were performed to evaluate the economic viability of some of these strains for the aquaculture industry. Results In addition to the three locations (Galerazamba, Manaure, and Pozos Colorados) reported in the literature three decades ago in the Colombian Caribbean, six new locations were registered (Salina Cero, Kangaru, Tayrona, Bahía Hondita, Warrego and Pusheo). All habitats sampled showed that chloride was the prevailing anion, as expected, because of their thalassohaline origin. There were significant differences in cyst diameter grouping strains in the following manner according to this parameter: 1) San Francisco Bay (SFB-Control, USA), 2) Galerazamba and Tayrona, 3) Kangarú, 4) Manaure, and 5) Salina Cero and Pozos Colorados. Chorion thickness values were smaller in Tayrona, followed by Salina Cero, Galerazamba, Manaure, SFB, Kangarú and Pozos Colorados. There were significant differences in naupliar size, grouping strains as follows (smallest to largest): 1) Galerazamba, 2) Manaure, 3) SFB, Kangarú, and Salina Cero, 4) Pozos Colorados, and 5) Tayrona. Overall, cyst quality analysis conducted on samples from Manaure, Galerazamba, and Salina Cero revealed that all sites exhibited a relatively high number of cysts.g-1. Essential fatty acids (EFA) analysis performed on nauplii from cyst samples from Manaure, Galerazamba, Salina Cero and Tayrona revealed that cysts

  1. Artemia cyst production in Russia

    NASA Astrophysics Data System (ADS)

    Litvinenko, Liudmila I.; Litvinenko, Aleksandr I.; Boiko, Elena G.; Kutsanov, Kirill

    2015-11-01

    In Western Siberia (Russia) there are about 100 Artemia lakes with total area over 1 600 km2. Geographically these lakes are located between 51°-56°N and 61°-82°E. In general these lakes are shallow (depth less than 1.5 m), small or medium size (0.1 to 10 km2); they are chloride; their total salinity is from 40 to 250 g/L. The harvesting of cysts per year is only in 20-40 lakes. In Russia 550 tons of dry Artemia cysts (14%-18% of the world production) were harvested annually. This includes about 350 tons in the Altai region and 200 tons in other regions. During our regular 20-year study period the cyst harvest was: 95 tons in Kurgan; 65 tons in Omsk, 20 tons in Novosibirsk, 20 tons in Tyumen. Ways of increasing cyst harvest in Russia are considered in this article. During the last 30 years the harvest of cysts in Russia has increased from 7-20 to 500-600 tons. A significant influence of dryness of the year was found on productivity in selected lakes, but taken for all the lakes together, the relationship was not significant. The optimal salinity for productivity of cysts in the lakes was determined. Analysis of productivity of the lakes and the harvesting results showed that the stocks of cysts are underutilized by approximately 1.7 times.

  2. Antifouling potential of the marine microalga Dunaliella salina.

    PubMed

    Gao, Min; Li, Fengchao; Su, Rongguo; Wang, Ke; Li, Xuzhao; Lu, Wei

    2014-11-01

    Marine organisms have usually been viewed as sources of environmentally friendly compounds with antifouling activity. We performed a series of operations to investigate the antifouling potential of the marine microalga Dunaliella salina. For the ethyl acetate crude extract, the antialgal activity was significant, and the EC50 value against Skeletonema costatum was 58.9 μg ml(-1). The isolated purified extract was tested for antifouling activity, the EC 50 value against S. costatum was 21.2 μg ml(-1), and the LC50 against Balanus amphitrite larvae was 18.8 μg ml(-1). Subsequently, both UHR-TOF-MS and GC-MS were used for the structural elucidation of the compounds, and a series of unsaturated and saturated 16- and 18-carbon fatty acids were detected. The data suggested that the fatty acid extracts from D. salina possess high antifouling activity, and could be used as substitutes for potent, toxic antifouling compounds.

  3. Marine Lactobacillus pentosus H16 protects Artemia franciscana from Vibrio alginolyticus pathogenic effects.

    PubMed

    Garcés, M E; Sequeiros, C; Olivera, N L

    2015-02-10

    Vibrio alginolyticus is an opportunistic pathogen which may affect different aquatic organisms. The aim of this study was to assess the probiotic properties and the protective mode of action of Lactobacillus pentosus H16 against V. alginolyticus 03/8525, through in vitro and in vivo studies using Artemia franciscana (hereafter Artemia). This strain showed antimicrobial activity against V. alginolyticus 03/8525 and Aeromonas salmonicida subsp. salmonicida ATCC33658 possibly related to lactobacilli organic acid production. It was able to survive at high rainbow trout bile concentrations and showed high selective adhesion to rainbow trout mucus (1.2×10(5)±8.0×10(3) cells cm(-2)). H16 outcompeted V. alginolyticus 03/8525 and A. salmonicida subsp. salmonicida ATCC33658, greatly reducing their adherence to rainbow trout mucus (64.8 and 74.1%, respectively). Moreover, H16 produced a cell-bound biosurfactant which caused an important decrease in the surface tension. H16 also protected Artemia nauplii against mortality when it was administered previous to V. alginolyticus 03/8525 inoculation. Furthermore, H16 bioencapsulated in Artemia, suggesting that it is possible to use live carriers in its administration. We conclude that the ability of L. pentosus H16 to selectively adhere to mucosal surfaces and produce cell-bound biosurfactants, displacing pathogenic strains, in addition to its antimicrobial activity, confer H16 competitive advantages against pathogens as demonstrated in in vivo challenge experiments. Thus, L. pentosus H16, a marine bacterium from the intestinal tract of hake, is an interesting probiotic for Artemia culture and also has the potential to prevent vibriosis in other aquaculture activities such as larvae culture and fish farming. PMID:25667335

  4. The occurrence of an exotic bisexual Artemia species, Artemia franciscana, in two coastal salterns of Shandong Province, China

    NASA Astrophysics Data System (ADS)

    Zheng, Bo; Sun, Shichun; Ma, Lin

    2004-10-01

    The alien halophilous Artemia species, Artemia franciscana, was found in Chengkou Saltern and Yangkou Saltern of Shandong Province, P.R. China. Although the indigenous parthenogenetic Artemia is detectable, the exotic species is dominant in both salterns. The cross-breeding tests between the exotic A. franciscana and 5 bisexual Artemia species were conducted. The results of hybridization and morphological observations on the exotic A. franciscana are briefly presented in this short communication.

  5. Organisms for Teaching: "Artemia salina": An Easily Cultured Invertebrate Ideally Suited for Ecological Studies.

    ERIC Educational Resources Information Center

    Ward-Booth, Kirsty; Reiss, Michael

    1988-01-01

    This paper includes a general account of the biology of the brine shrimp, instructions on how the organism may be cultured, the results of some experiments on the ecology and population biology of the species, and some suggestions for further studies. (Author/CW)

  6. Biological screening of araripe basin medicinal plants using Artemia salina Leach and pathogenic bacteria

    PubMed Central

    da Costa, José Galberto M.; Campos, Adriana R.; Brito, Samara A.; Pereira, Carla Karine B.; Souza, Erlânio O.; Rodrigues, Fabíola Fernandes G.

    2010-01-01

    Background: Many medicinal plant species from the Araripe Basin are widely known and used in folk medicine and for commercial manufacturing of phytotherapeutic products. Few ethnobotanical and pharmacological studies have been undertaken in this region, however, in spite of the great cultural and biological diversity found there. Materials and Methods: Extracts of 11 plant species collected from Ceará state, Brazil, were subjected to the brine shrimp lethality test in order to detect potential sources of novel cytotoxic, antitumor compounds. The larvicidal activity, based on the percentage of larval mortality, was evaluated after 24 h exposure to the treatments. Results: All species tested showed good larvicidal activity as compared to a reference compound and literature data. The extract from Vanillosmopsis arborea was the most active with an LC50 of 3.9 μg/ml. Best results were shown by Lantana montevidensis against Pseudomonas aeruginosa [minimum inhibitory concentration (MIC) 8μg/ml] and Escherichia coli (MIC 32 μg/ml), Zanthoxylum rhoifolium against E. coli (MIC, 256 μg/ml) and Staphylococcus aureus (MIC 64 μg/ml) and Croton zenhtneri against S. aureus (MIC 64 μg/ml). Conclusion: Chemical tests indicated that a wide variety of natural product classes was present in those extracts that showed significant activities in the bioassays. PMID:21120038

  7. Combined toxicity of four toxicants (Cu, Cr, oil, oil dispersant) to Artemia salina

    SciTech Connect

    Verriopoulos, G.; Moraitou-Apostolopoulou, M.; Milliou, E.

    1987-03-01

    In sea waters multicontaminant pollution appears to be the rule rather than the exception. For a realistic approach to pollution effects it is essential to estimate the combined toxicity of two or more chemicals. There is a need to understand the mechanisms of quantify the effects of multiple toxicity in order to provide responsible authorities with rational estimate of the effects of chemical mixtures. Thus the potential toxic effects of mixtures of toxicants has recently become a subject of growing scientific interest. In this paper the authors have tried to estimate the joint toxicity of some pollutants commonly found in nearshore polluted waters: two metals, copper and chromium; an oil (Tunesian crude oil zarzaitine type); and an oil dispersant (Finasol OSR-2).

  8. Nonhatching Decapsulated Artemia Cysts As a Replacement to Artemia Nauplii in Juvenile and Adult Zebrafish Culture.

    PubMed

    Tye, Marc; Rider, Dana; Duffy, Elizabeth A; Seubert, Adam; Lothert, Brogen; Schimmenti, Lisa A

    2015-12-01

    Feeding Artemia nauplii as the main nutrition source for zebrafish is a common practice for many research facilities. Culturing live feed can be time-consuming and requires additional equipment to be purchased, maintained, and cleaned. Nonhatching decapsulated Artemia cysts (decaps) are a commercially available product that can be fed directly to fish. Several other ornamental fish species have been successfully cultured using decaps. Replacing Artemia nauplii with decaps could reduce the overall time and costs associated with the operation of a zebrafish facility. The objective of this study was to determine if decaps could be a suitable replacement to Artemia nauplii in juvenile and adult zebrafish culture. Wild-type zebrafish were fed one of three dietary treatments: decaps only, nauplii only, or a standard consisting of nauplii plus a commercially prepared pellet food. Survival, growth (length and weight), and embryo production were analyzed between the treatments. Fish receiving the decap diet demonstrated a significantly higher growth and embryo production when compared to the fish receiving the nauplii-only diet. When comparing the decap fish to the standard fish, no significant difference was found in mean survival, mean weight at 90 days postfertilization, or mean embryo production. It was determined that nonhatching decapsulated Artemia cysts can be used as a suitable replacement to Artemia nauplii in juvenile and adult zebrafish culture.

  9. Nonhatching Decapsulated Artemia Cysts As a Replacement to Artemia Nauplii in Juvenile and Adult Zebrafish Culture.

    PubMed

    Tye, Marc; Rider, Dana; Duffy, Elizabeth A; Seubert, Adam; Lothert, Brogen; Schimmenti, Lisa A

    2015-12-01

    Feeding Artemia nauplii as the main nutrition source for zebrafish is a common practice for many research facilities. Culturing live feed can be time-consuming and requires additional equipment to be purchased, maintained, and cleaned. Nonhatching decapsulated Artemia cysts (decaps) are a commercially available product that can be fed directly to fish. Several other ornamental fish species have been successfully cultured using decaps. Replacing Artemia nauplii with decaps could reduce the overall time and costs associated with the operation of a zebrafish facility. The objective of this study was to determine if decaps could be a suitable replacement to Artemia nauplii in juvenile and adult zebrafish culture. Wild-type zebrafish were fed one of three dietary treatments: decaps only, nauplii only, or a standard consisting of nauplii plus a commercially prepared pellet food. Survival, growth (length and weight), and embryo production were analyzed between the treatments. Fish receiving the decap diet demonstrated a significantly higher growth and embryo production when compared to the fish receiving the nauplii-only diet. When comparing the decap fish to the standard fish, no significant difference was found in mean survival, mean weight at 90 days postfertilization, or mean embryo production. It was determined that nonhatching decapsulated Artemia cysts can be used as a suitable replacement to Artemia nauplii in juvenile and adult zebrafish culture. PMID:25495227

  10. Further characterization of the cathepsin L-associated protein and its gene in two species of the brine shrimp, Artemia.

    PubMed

    Liu, Liqian; Warner, Alden H

    2006-12-01

    The major cysteine protease in embryos and larvae of the brine shrimp Artemia franciscana is a heterodimer composed of a cathepsin L-like polypeptide of 28.5 kDa and a 31.5 kDa polypeptide called the cathepsin L-associated protein or CLAP. In a previous study, CLAP was shown to be a cell adhesion protein containing two Fas I domains and two GTP/ATP binding sites known as Walker A and B motifs. Here, we have characterized CLAP and its genes to better understand the role of this protein in Artemia development. The polymerase chain reaction was used to investigate the structure of the CLAP gene in two species of Artemia, the New World bisexual diploid A. franciscana and the Old World parthenogenetic tetraploid Artemia parthenogenetica. The protein coding region of the CLAP gene from each species was 99.5% identical for a protein of 332 amino acids, while the 3' non-coding region, representing nearly 45% of the gene, was only 86% identical between the two related species. However, while the CLAP gene is intronless in A. franciscana, in A. parthenogenetica the gene contained a mini-intron of 30 base pairs in the 3' non-coding region. The sequences representing the CLAP gene in A. franciscana and A. parthenogenetica have been entered into the NCBI database as AY757920 and DQ100385, respectively. Northern blot analysis showed that while the cathepsin L gene is expressed constitutively in Artemia franciscana embryos and young larvae, the CLAP gene is not expressed in late embryos and young larvae. In contrast, Western blots indicated that CLAP is present in developing embryos and young larvae, at least to the first larval molt, supporting results obtained previously showing CLAP's resistance to degradation by its dimeric partner, cathepsin L. At the protein level we showed that the GTP/ATP binding sites in CLAP are functional with rate constants of 0.024 and 0.022 for GTP and ATP hydrolase activity, respectively. GTP but not ATP also had a slight stimulatory effect on

  11. Post-translationally modified tubulins in Artemia: prelarval development in the absence of detyrosinated tubulin.

    PubMed

    Langdon, C M; Freeman, J A; MacRae, T H

    1991-11-01

    The synthesis of post-translationally modified tubulins was examined during Artemia development. Tubulin, either purified to homogeneity or in cell-free extracts, was blotted to nitrocellulose and probed with a panel of antibodies. When purified tubulin was examined, tyrosinated tubulin underwent a large decrease as development progressed and this was accompanied by the appearance of detyrosinated tubulin in samples from organisms developed 24 hr. The inclusion of carboxypeptidase inhibitors had a small effect on the relative amounts of tyrosinated and detyrosinated tubulins in 24-hr preparations. The amount of alpha- and beta-tubulin in cell-free extracts of Artemia either remained relatively constant during development or increased slightly. The same result was obtained for acetylated and tyrosinated tubulin. Detyrosinated tubulin first appeared in 24-hr cell-free extracts and was only post-translationally modified tubulin to increase, relative to the total amount of tubulin, as the brine shrimp developed. As revealed by immunofluorescence staining, detyrosinated tubulin occurred in many cell types of developing nauplii and was prominently displayed in mitotic figures. Artemia, a complex metazoan animal, is thus able to grow for an extended period of time in the absence of detyrosinated tubulin. This isoform is however, synthesized in early larvae and may be required for the development of elongated cells including those which encircle the gut. Detyrosination remains as the only developmentally related change observed for brine shrimp tubulin. PMID:1936554

  12. Carotenoid fluorescence in Dunaliella salina

    PubMed Central

    van Es, Marjon A.; Janssen, Marcel; Brandenburg, Willem A.; Wijffels, René H.

    2010-01-01

    Dunaliella salina is a halotolerant green alga that is well known for its carotenoid producing capacity. The produced carotenoids are mainly stored in lipid globules. For various research purposes, such as production and extraction kinetics, we would like to determine and/or localise the carotenoid globules in vivo. In this study, we show that the carotenoid-rich globules emit clear green fluorescence, which can be used in, for example, fluorescence microscopy (e.g. CLSM) to obtain pictures of the cells and their carotenoid content. PMID:20835349

  13. Carotenoid fluorescence in Dunaliella salina.

    PubMed

    Kleinegris, Dorinde M M; van Es, Marjon A; Janssen, Marcel; Brandenburg, Willem A; Wijffels, René H

    2010-10-01

    Dunaliella salina is a halotolerant green alga that is well known for its carotenoid producing capacity. The produced carotenoids are mainly stored in lipid globules. For various research purposes, such as production and extraction kinetics, we would like to determine and/or localise the carotenoid globules in vivo. In this study, we show that the carotenoid-rich globules emit clear green fluorescence, which can be used in, for example, fluorescence microscopy (e.g. CLSM) to obtain pictures of the cells and their carotenoid content.

  14. Evaluation of toxicity of polluted marine sediments from Bahia Salina Cruz, Mexico.

    PubMed

    Gonzalez-Lozano, Maria Cristina; Mendez-Rodriguez, Lia C; Maeda-Martinez, Alejandro M; Murugan, Gopal; Vazquez-Botello, Alfonso

    2010-01-01

    Bahia Salina Cruz, Oaxaca, Mexico is a major center of oil and refined product distribution on the Mexican Pacific coast. From the start of oil industry operations in 1979, negative effects from discharges of treated effluents in the bay have been a constant concern for local communities. We analyzed 28 surface sediment samples obtained in June, 2002 to evaluate the level of toxicity in the littoral zone, port-harbor, and La Ventosa estuary in Bahia Salina Cruz. The extractable organic matter concentration was high (1,213 to 7,505 micro g g(-1)) in 5 of 7 stations from the port and harbor, whereas it was low in 12 of 16 stations in the littoral zone (36 to 98 micro g g(-1)). The total aromatic hydrocarbon concentration was highest (57 to 142 micro g g(-1)) in the port and harbor compared to the La Ventosa estuary and the littoral zone. Among the heavy metals analyzed, cadmium exceeded the effects range-low values associated with adverse biological effects. The geo-accumulation index of sediments was moderate to strong contamination at 5 stations in the nonlittoral and 6 stations in the littoral zone. The enrichment of lead, zinc, and cadmium at 5 stations from the littoral, port, and harbor suggest that these metals are of anthropogenic origin. Bioassay tests of elutriates of sediments on nauplii of Artemia franciscana and Artemia sp. showed that the port and harbor were more toxic than the La Ventosa estuary and the coastal zone. The Microtox test (Vibrio fischeri) did not show a similar response with the solid phase of the sediments. The results of this study indicate that the high levels of organic content and metals in the sediments of port-harbor and the La Ventosa estuary are mainly caused by anthropogenic activities.

  15. Antifouling potential of the marine microalga Dunaliella salina.

    PubMed

    Gao, Min; Li, Fengchao; Su, Rongguo; Wang, Ke; Li, Xuzhao; Lu, Wei

    2014-11-01

    Marine organisms have usually been viewed as sources of environmentally friendly compounds with antifouling activity. We performed a series of operations to investigate the antifouling potential of the marine microalga Dunaliella salina. For the ethyl acetate crude extract, the antialgal activity was significant, and the EC50 value against Skeletonema costatum was 58.9 μg ml(-1). The isolated purified extract was tested for antifouling activity, the EC 50 value against S. costatum was 21.2 μg ml(-1), and the LC50 against Balanus amphitrite larvae was 18.8 μg ml(-1). Subsequently, both UHR-TOF-MS and GC-MS were used for the structural elucidation of the compounds, and a series of unsaturated and saturated 16- and 18-carbon fatty acids were detected. The data suggested that the fatty acid extracts from D. salina possess high antifouling activity, and could be used as substitutes for potent, toxic antifouling compounds. PMID:25096202

  16. Effect of n-3 HUFA levels in rotifers and Artemia on growth and survival of larval black sea bream ( Sparus macrocephalus)

    NASA Astrophysics Data System (ADS)

    Liu, Jingke; Li, Kuiran; Huang, Bingxin; Chen, Xiaolin

    2004-12-01

    Requirement for dietary n-3 HUFA (n-3 highly unsaturated fatty acid) for growth and survival of black sea bream ( Sparus macrocephalus) larvae was studied using rotifers and Artemia at various levels of n-3 HUFA. Five treatments with rotifers and Artemia differing in n-3 HUFA were prepared by enriching them with various oil emulsions. Results indicated that dietary n-3 HUFA significantly influence fish n-3 HUFA levels and are essential for growth and survival of black sea bream larvae. The results also indicated that the incorporation of n-3HUFA TG (triacylglycerols) into tissues of larval black sea bream was more effective from natural fish oil in comparison with n-3 HUFA fatty acid ethyl esters from ethyl-esterified oil.

  17. Long-term Lethal Toxicity Test with the Crustacean Artemia franciscana

    PubMed Central

    Manfra, Loredana; Savorelli, Federica; Pisapia, Marco; Magaletti, Erika; Cicero, Anna Maria

    2012-01-01

    Our research activities target the use of biological methods for the evaluation of environmental quality, with particular reference to saltwater/brackish water and sediment. The choice of biological indicators must be based on reliable scientific knowledge and, possibly, on the availability of standardized procedures. In this article, we present a standardized protocol that used the marine crustacean Artemia to evaluate the toxicity of chemicals and/or of marine environmental matrices. Scientists propose that the brine shrimp (Artemia) is a suitable candidate for the development of a standard bioassay for worldwide utilization. A number of papers have been published on the toxic effects of various chemicals and toxicants on brine shrimp (Artemia). The major advantage of this crustacean for toxicity studies is the overall availability of the dry cysts; these can be immediately used in testing and difficult cultivation is not demanded1,2. Cyst-based toxicity assays are cheap, continuously available, simple and reliable and are thus an important answer to routine needs of toxicity screening, for industrial monitoring requirements or for regulatory purposes3. The proposed method involves the mortality as an endpoint. The numbers of survivors were counted and percentage of deaths were calculated. Larvae were considered dead if they did not exhibit any internal or external movement during several seconds of observation4. This procedure was standardized testing a reference substance (Sodium Dodecyl Sulfate); some results are reported in this work. This article accompanies a video that describes the performance of procedural toxicity testing, showing all the steps related to the protocol. PMID:22525984

  18. Helminth parasites of Artemia franciscana (Crustacea: Branchiopoda) in the Great Salt Lake, Utah: first data from the native range of this invader of European wetlands.

    PubMed

    Redon, Stella; Berthelemy, Nicole J; Mutafchiev, Yasen; Amat, Francisco; Georgiev, Boyko B; Vasileva, Gergana P

    2015-01-01

    The present study is the first survey on the role of Artemia franciscana Kellogg as intermediate host of helminth parasites in its native geographical range in North America (previous studies have recorded nine cestode and one nematode species from this host in its invasive habitats in the Western Mediterranean). Samples of Artemia franciscana were collected from four sites in the Great Salt Lake (GSL), Utah, across several months (June-September 2009). A. franciscana serves as intermediate host of five helminth species in this lake. Four of them are cestodes: three hymenolepidids, i.e. Confluaria podicipina (Szymanski, 1905) (adults parasitic in grebes), Hymenolepis (sensu lato) californicus Young, 1950 (adults parasitic in gulls), Wardium sp. (definitive host unknown, probably charadriiform birds), and one dilepidid, Fuhrmannolepis averini Spassky et Yurpalova, 1967 (adults parasitic in phalaropes). In addition, an unidentified nematode of the family Acuariidae was recorded. Confluaria podicipina is the most prevalent and abundant parasite at all sampling sites, followed by H. (s. l.) californicus. The species composition of the parasites and the spatial variations in their prevalence and abundance reflect the abundance and distribution of aquatic birds serving as their definitive hosts. The temporal dynamics of the overall helminth infections exhibits the highest prevalence in the last month of study at each site (August or September). This native population of A. franciscana from GSL is characterised with higher prevalence, intensity and abundance of the overall cestode infection compared to the introduced populations of this species in the Palaearctic Region. The values of the infection descriptors in the native population of A. franciscana are slightly lower or in some cases similar to those of the Palaearctic species Artemia parthenogenetica Barigozzi (diploid populations) and Artemia salina (Linnaeus) in their native habitats. PMID:26040582

  19. [Rhodomonas salina (Cryptophyta) pastes as feed for Brachionus plicatilis (Rotifera)].

    PubMed

    Guevara, Miguel; Bastardo, Leandro; Cortez, Roraysi; Arredondo-Vega, Bertha; Romero, Lolymar; Gómez, Patricia

    2011-12-01

    Rotifers are an important live feed for first feeding larvae of many fish species. The use of concentrated algae cells in the mass culture of the rotifer Brachionus plicatilis (Brachionidae) has opened new horizons for research on this organism. Pastes of Rhodomonas salina (Pyrenomonadaceae) obtained either by centrifugation or flocculation with chitosan were preserved, with or without vitamin C, at -20 degrees C for four weeks and were evaluated biochemically (proteins, lipids, pigments and fatty acids contents) and subsequently, were used to feed the rotifer Brachionus plicatilis at a ratio of 25 mg/L/day. Four different microalgae pastes were prepared: (1) centrifuged and preserved with vitamin C (CV), (2) centrifuged and preserved without vitamin C (C), (3) flocculated and with vitamin C (FV) and (4) flocculated without vitamin C (F). All treatments showed similar contents of proteins and total lipids with respect to control culture (a fresh culture of R. salina), with mean values of 40.0 +/- 2.32% and 12.0 +/- 1.45%, respectively. The pheophytin a/chlorophyll a ratio, a general indicator of the chemical status of microalgal concentrates, was similar (0.09-0.11) between centrifuged pastes and control culture, but was found to be higher in flocculated pastes (1.28-1.48). The fatty acid profile varied with respect to the control culture, mainly in the proportion of the essential polyunsaturated fatty acids (PUFAs): eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Total PUFAs, EPA and DHA contents were statistically similar between centrifuged pastes and control culture (PUFAs: 47%, EPA: 4% and DHA: 4.7%), whereas values obtained for flocculated pastes were significantly lower. The rotifers grew equally well when fed with centrifuged pastes or control culture (maximum density: 320 rotifers/mL; instantaneous growth rate: 0.23 rotifers/day, fecundity: 1.49 eggs/female and productivity: 43 x 10(3) rotifers/L/day. No significant effect of vitamin C was

  20. Embryonic diapause in two species of brine shrimp: Artemia monica and Artemia franciscana

    SciTech Connect

    Drinkwater, L.E.

    1986-01-01

    The brine shrimp, Artemia, has the capacity to produce encysted embryos which are resistant to severe environmental conditions. Upon release from the ovisac, these embryos, or cysts, do not hatch, but remain in a state of developmental arrest imposed by some unknown endogenous mechanism. However, once the proper abiotic signal is received, the embryo is free to resume development. Regulation of this embryonic diapause in two related species of brine shrimp, Artemia franciscana and Artemia monica, is studied. The abiotic cues which terminate diapause and the possibility of a regulatory mechanism involving depressed intracellular pH (pH/sub i/) are investigated. /sup 31/P-NMR studies show that pH/sub i/ of diapause cysts of both species is alkaline, greater than or equal to 7.9, essentially the same as that of activated cysts. A franciscana, which inhabits an unpredictable environment, is activated by several cues: low temperature, dehydration, and elevated levels of CO/sub 2/. A. monica, found in a fairly stable body of water with regular seasonal changes in temperature, breaks diapause only upon exposure to low temperature. Induction of anoxybiosis in diapause and activated cysts is studied using /sup 31/P-NMR to reveal that diapause cysts acidify rapidly in response to anoxia; pH/sub i/ falls to about 7.2 in 30 minutes, much like activated cysts, indicating the presence of a fairly active metabolism. The effects of salinity on cyst activation, hatching, water content, and carbohydrate metabolism are examined.

  1. Strong environmental tolerance of Artemia under very high pressure

    NASA Astrophysics Data System (ADS)

    Minami, K.; Ono, F.; Mori, Y.; Takarabe, K.; Saigusa, M.; Matsushima, Y.; Saini, N. L.; Yamashita, M.

    2010-03-01

    It was shown by the present authors group that a tardigrade in its tun-state can survive after exposed to 7.5 GPa for 13 hours. We have extended this experiment to other tiny animals searching for lives under extreme conditions of high hydrostatic pressure. Artemia, a kind of planktons, in its dried egg-state have strong environmental tolerance. Dozens of Artemia eggs were sealed in a small Teflon capsule together with a liquid pressure medium, and exposed to the high hydrostatic pressure of 7.5 GPa. After the pressure was released, they were soaked in seawater to observe hatching rate. It was proved that 80-90% of the Artemia eggs were alive and hatched into Nauplii after exposed to the maximum pressure of 7.5 GPa for up to 48 hours. Comparing with Tardigrades, Artemia are four-times stronger against high pressure.

  2. Toxicity Effect of Silver Nanoparticles in Brine Shrimp Artemia

    PubMed Central

    Arulvasu, Chinnasamy; Jennifer, Samou Michael; Prabhu, Durai; Chandhirasekar, Devakumar

    2014-01-01

    The present study revealed the toxic effect of silver nanoparticles (AgNPs) in Artemia nauplii and evaluated the mortality rate, hatching percentage, and genotoxic effect in Artemia nauplii/cysts. The AgNPs were commercially purchased and characterized using field emission scanning electron microscope with energy dispersive X-ray spectroscopy. Nanoparticles were spherical in nature and with size range of 30–40 nm. Artemia cysts were collected from salt pan, processed, and hatched in sea water. Artemia nauplii (II instar) were treated using silver nanoparticles of various nanomolar concentrations and LC50 value (10 nM) and mortality rate (24 and 48 hours) was evaluated. Hatching percentage of decapsulated cysts treated with AgNPs was examined. Aggregation of AgNPs in the gut region of nauplii was studied using phase contrast microscope and apoptotic cells in nauplii stained with acridine orange were observed using fluorescence microscope. DNA damage of single cell of nauplii was determined by comet assay. This study showed that as the concentration of AgNPs increased, the mortality rate, aggregation in gut region, apoptotic cells, and DNA damage increased in nauplii, whereas the percentage of hatching in Artemia cysts decreased. Thus this study revealed that the nanomolar concentrations of AgNPs have toxic effect on both Artemia nauplii and cysts. PMID:24516361

  3. Porfirio Salinas and His Bluebonnet Legacy.

    ERIC Educational Resources Information Center

    Coker, Dolores M.

    Porfirio Salinas has been hailed the best painter of the Texas hill country and its bluebonnets. Born on November 6, 1910, Porfirio's teachers recognized and encouraged his drawing ability. When Porfirio found employment after school in a graphics company that also sold art supplies, he met Robert Wood, recognized for his Texas landscapes, and…

  4. The proteolytic digestive activity and growth during ontogeny of Parachromis dovii larvae (Pisces: Cichlidae) using two feeding protocols.

    PubMed

    Quirós Orlich, José R; Valverde Chavarría, Silvia; Ulloa Rojas, Juan B

    2014-08-01

    The proteolytic digestive activity and growth of Parachromis dovii larvae during the ontogeny were evaluated in a recirculation system using two feeding strategies during a 28-day period. Larvae were reared using two feeding protocols (three replicates each): (A) Artemia nauplii (at satiation), fed from exogenous feeding [8 days after hatching (DAH)] until 15 DAH followed by nauplii substitution by formulated feed (20% day(-1)) until 20 DAH and then formulated feed until 28 DAH; (B) formulated feed (100 % BW daily) from exogenous feeding until 28 DAH. Levels of acid (pepsin type) and alkaline digestive proteases as well as growth and survival of larvae were measured along the feeding period. Survival was high and similar between treatments: 98.9 ± 0.0 for Artemia, 97.3 ± 0.0% for formulated feed. The specific growth rate for length and weight was higher in larvae fed with Artemia nauplii than in larvae reared with formulated feed: 3.4 ± 0.1 versus 1.8 ± 0.1% day(-1) for body length (P = 0.009) and 12.2 ± 0.1 versus 6.5 ± 0.3% day(-1) for body weight (P = 0.002). The acid and alkaline proteolytic activity was detected, in both treatments, from the beginning of the experiment, at 8 DAH. The total enzymatic activity (U larva(-1)) for acid and alkaline proteases was higher in larvae reared with Artemia after 12 DAH, whereas the specific enzymatic activity was similar for both enzyme types in the two treatments. The results suggest that P. dovii larvae were capable to digest formulated diets from the beginning of exogenous feeding and that they could be reared with formulated feeds. However, the formulated feed used should be nutritionally improved because of the poor growth obtained in this research.

  5. [Larva migrans].

    PubMed

    Chabasse, D; Le Clec'h, C; de Gentile, L; Verret, J L

    1995-01-01

    Larbish, cutaneous larva migrans or creeping eruption, is a serpiginous cutaneous eruption caused by skin penetration of infective larva from various animal nematodes. Hookworms (Ancylostoma brasiliense, A. caninum) are the most common causative parasites. They live in the intestines of dogs and cats where their ova are deposited in the animal feces. In sandy and shady soil, when temperature and moisture are elevated, the ova hatch and mature into infective larva. Infection occurs when humans have contact with the infected soil. Infective larva penetrate the exposed skin of the body, commonly around the feet, hands and buttocks. In humans, the larva are not able to complete their natural cycle and remain trapped in the upper dermis of the skin. The disease is widespread in tropical or subtropical regions, especially along the coast on sandy beaches. The diagnosis is easy for the patient who is returning from a tropical or subtropical climate and gives a history of beach exposure. The characteristic skin lesion is a fissure or erythematous cord which is displaced a few millimeters each day in a serpiginous track. Scabies, the larva currens syndrome due to Strongyloides stercoralis, must be distinguished from other creeping eruptions and subcutaneous swelling lesions caused by other nematodes or myiasis. Medical treatments are justified because it shortens the duration of the natural evolution of the disease. Topical tiabendazole is safe for localized invasions, but prolonged treatment may be necessary. Oral thiabendazole treatment for three days is effective, but sometimes is associated with adverse effects. Trials using albendazole for one or four consecutive days appear more efficacious. More recent trials using ivermectine showed that a single oral dose can cure 100% of the patients; thus, this drug looks very promising as a new form of therapy. Individual prophylaxis consists of avoiding skin contact with soil which has been contaminated with dog or cat feces

  6. [Larva migrans].

    PubMed

    Chabasse, D; Le Clec'h, C; de Gentile, L; Verret, J L

    1995-01-01

    Larbish, cutaneous larva migrans or creeping eruption, is a serpiginous cutaneous eruption caused by skin penetration of infective larva from various animal nematodes. Hookworms (Ancylostoma brasiliense, A. caninum) are the most common causative parasites. They live in the intestines of dogs and cats where their ova are deposited in the animal feces. In sandy and shady soil, when temperature and moisture are elevated, the ova hatch and mature into infective larva. Infection occurs when humans have contact with the infected soil. Infective larva penetrate the exposed skin of the body, commonly around the feet, hands and buttocks. In humans, the larva are not able to complete their natural cycle and remain trapped in the upper dermis of the skin. The disease is widespread in tropical or subtropical regions, especially along the coast on sandy beaches. The diagnosis is easy for the patient who is returning from a tropical or subtropical climate and gives a history of beach exposure. The characteristic skin lesion is a fissure or erythematous cord which is displaced a few millimeters each day in a serpiginous track. Scabies, the larva currens syndrome due to Strongyloides stercoralis, must be distinguished from other creeping eruptions and subcutaneous swelling lesions caused by other nematodes or myiasis. Medical treatments are justified because it shortens the duration of the natural evolution of the disease. Topical tiabendazole is safe for localized invasions, but prolonged treatment may be necessary. Oral thiabendazole treatment for three days is effective, but sometimes is associated with adverse effects. Trials using albendazole for one or four consecutive days appear more efficacious. More recent trials using ivermectine showed that a single oral dose can cure 100% of the patients; thus, this drug looks very promising as a new form of therapy. Individual prophylaxis consists of avoiding skin contact with soil which has been contaminated with dog or cat feces

  7. Porting salinas to the windows platform.

    SciTech Connect

    Reese, Garth M.; Wilson, Christopher Riley

    2006-06-01

    The ASC program has enabled significant development of high end engineering applications on massively parallel machines. There is a great benefit in providing these applications on the desktop of the analysts and designers, at least insofar as the small models may be run on these platforms, thus providing a tool set that spans the application needs. This effort documents the work of porting Salinas to the WINDOWS{trademark} platform. Selection of the tools required to compile, link, test and run Salinas in this environment is discussed. Significant problems encountered along the way are listed along with an estimation of the overall cost of the port. This report may serve as a baseline for streamlining further porting activities with other ASC codes.

  8. Variant subunit specificity in the quaternary structure of Artemia hemoglobin.

    PubMed

    Vandenberg, Cassandra J; Matthews, Charles M; Trotman, Clive N A

    2002-08-01

    The brine shrimp Artemia has three extracellular hemoglobins (Hbs) that are developmentally expressed and exhibit distinct oxygen-binding characteristics (Heip, Moens, and Kondo 1978; Heip et al. 1978 ). These Hbs are composed of two polymers, each of which comprises nine covalently linked globin domains. Although the cDNA sequences of two nine-domain globins from Artemia have been published, there is evidence for the existence of further expressed globin genes (Manning, Trotman, and Tate 1990 ). In the present study extensive analysis at the cDNA and genomic levels was performed in order to determine the globin gene copy number in Artemia. Sequence and Southern analysis suggest that four Hb polymers (T1, T2, C1, and C2) are expressed in Artemia. In addition, there is also at least one globin pseudogene. Protein sequencing of the native Hbs revealed that there are limitations on which two polymers can associate. The composition of the Hbs has been determined to be: Hb I, C1C2; Hb II, C1T2; and Hb III, T1T2. These pairings allow the levels of the three Artemia Hbs to be regulated independently by polymer expression alone, therefore explaining the previously inconsistent developmental and hypoxia-induced expression patterns. PMID:12140240

  9. Dunaliella salina Hsp90 is halotolerant.

    PubMed

    Chen, Xiang-Jun; Wu, Ming-Jie; Jiang, Yan; Yang, Yi; Yan, Yong-Bin

    2015-04-01

    Dunaliella salina is a unicellular green alga with exceptional halotolerance. Although the D. salina cells are capable to proliferate in hypersaline medium, the intracellular salt concentrations are maintained at a low level. Thus the extracellular but not intracellular Dunaliella proteins are expected to be highly halotolerant. In this research, we compared the salt-dependence of the activity and stability of Hsp90s from the halotolerant alga D. salina (dsHsp90) and the mesophilic alga Chlamydomonas reinhardtii (crHsp90). We found that the ATPase activity of crHsp90 could be enhanced about six-fold by 2M NaCl, while the activity of dsHsp90 showed a much weaker dependence on salinity. When denatured by urea, both crHsp90 and dsHsp90 exhibited an apparent three-state unfolding with the population of an unfolding intermediate. High salinity significantly decreased the Gibbs free energy change of crHsp90 but not dsHsp90 for the transition from the native state to the intermediate. The little dependence of dsHsp90 activity and folding on salinity suggests that dsHsp90 is halotolerant though it is an intracellular protein. We propose that the halotolerance of intracellular Dunaliella proteins might play a role in fighting against the transient intracellular salt fluctuations during hyperosmotic or hypoosmotic shock.

  10. The effects of different routes of inulin administration on gut microbiota and survival rate of Indian white shrimp post-larvae (Fenneropenaeus indicus)

    PubMed Central

    Hoseinifar, Seyed Hossein; Zare, Parviz; Kolangi Miandare, Hamed

    2015-01-01

    The present study investigates the effects of different routes of inulin administration as prebiotic on gut microbiota and survival rate of Indian white shrimp post-larvae. Four hundred and fifty Indian white shrimp post-larvae (PL1) were stocked in nine tanks. The tanks were assigned into three treatments: feeding with inulin-treated (110 mg L-1) Artemia nauplii (I-T), feeding with inulin-enriched (110 mg L-1) Artemia nauplii (I-E) and control which repeated triplicates. Feeding trial was performed until PL11 stage and then gut microbiota was studied using culture based method. Also, survival rate was calculated at the end of feeding trial. Our results showed that feeding on inulin enriched or treated Artemia nauplii had no significant effect on total viable culturable autochthonous bacteria and Vibrio spp. levels of the gut microbiota (p > 0.05). However, a remarkable increase of lactic acid bacteria levels (LAB) was observed in I-E treatment (p < 0.05). Administration of inulin enriched Artemia nauplii significantly elevated survival rates of Indian white shrimp post-larvae (p < 0.05). These results encourage administration of prebiotic-enriched Artemia nauplii in post larval stage of Indian white shrimp but determination the mode of action of prebiotic on various aspects of shrimp larviculture merit further research. PMID:26973770

  11. The effects of different routes of inulin administration on gut microbiota and survival rate of Indian white shrimp post-larvae (Fenneropenaeus indicus).

    PubMed

    Hoseinifar, Seyed Hossein; Zare, Parviz; Kolangi Miandare, Hamed

    2015-01-01

    The present study investigates the effects of different routes of inulin administration as prebiotic on gut microbiota and survival rate of Indian white shrimp post-larvae. Four hundred and fifty Indian white shrimp post-larvae (PL1) were stocked in nine tanks. The tanks were assigned into three treatments: feeding with inulin-treated (110 mg L(-1)) Artemia nauplii (I-T), feeding with inulin-enriched (110 mg L(-1)) Artemia nauplii (I-E) and control which repeated triplicates. Feeding trial was performed until PL11 stage and then gut microbiota was studied using culture based method. Also, survival rate was calculated at the end of feeding trial. Our results showed that feeding on inulin enriched or treated Artemia nauplii had no significant effect on total viable culturable autochthonous bacteria and Vibrio spp. levels of the gut microbiota (p > 0.05). However, a remarkable increase of lactic acid bacteria levels (LAB) was observed in I-E treatment (p < 0.05). Administration of inulin enriched Artemia nauplii significantly elevated survival rates of Indian white shrimp post-larvae (p < 0.05). These results encourage administration of prebiotic-enriched Artemia nauplii in post larval stage of Indian white shrimp but determination the mode of action of prebiotic on various aspects of shrimp larviculture merit further research. PMID:26973770

  12. Copepods enhance nutritional status, growth and development in Atlantic cod (Gadus morhua L.) larvae - can we identify the underlying factors?

    PubMed

    Karlsen, Ørjan; van der Meeren, Terje; Rønnestad, Ivar; Mangor-Jensen, Anders; Galloway, Trina F; Kjørsvik, Elin; Hamre, Kristin

    2015-01-01

    The current commercial production protocols for Atlantic cod depend on enriched rotifers and Artemia during first-feeding, but development and growth remain inferior to fish fed natural zooplankton. Two experiments were conducted in order to identify the underlying factors for this phenomenon. In the first experiment (Exp-1), groups of cod larvae were fed either (a) natural zooplankton, mainly copepods, increasing the size of prey as the larvae grew or (b) enriched rotifers followed by Artemia (the intensive group). In the second experiment (Exp-2), two groups of larvae were fed as in Exp-1, while a third group was fed copepod nauplii (approximately the size of rotifers) throughout the larval stage. In both experiments, growth was not significantly different between the groups during the first three weeks after hatching, but from the last part of the rotifer feeding period and onwards, the growth of the larvae fed copepods was higher than that of the intensive group. In Exp-2, the growth was similar between the two copepod groups during the expeimental period, indicating that nutrient composition, not prey size caused the better growth on copepods. Analyses of the prey showed that total fatty acid composition and the ratio of phospholipids to total lipids was slightly different in the prey organisms, and that protein, taurine, astaxanthin and zinc were lower on a dry weight basis in rotifers than in copepods. Other measured nutrients as DHA, all analysed vitamins, manganese, copper and selenium were similar or higher in the rotifers. When compared to the present knowledge on nutrient requirements, protein and taurine appeared to be the most likely limiting nutrients for growth in cod larvae fed rotifers and Artemia. Larvae fed rotifers/Artemia had a higher whole body lipid content than larvae fed copepods at the end of the experiment (stage 5) after the fish had been fed the same formulated diet for approximately 2 weeks.

  13. Copepods enhance nutritional status, growth and development in Atlantic cod (Gadus morhua L.) larvae - can we identify the underlying factors?

    PubMed

    Karlsen, Ørjan; van der Meeren, Terje; Rønnestad, Ivar; Mangor-Jensen, Anders; Galloway, Trina F; Kjørsvik, Elin; Hamre, Kristin

    2015-01-01

    The current commercial production protocols for Atlantic cod depend on enriched rotifers and Artemia during first-feeding, but development and growth remain inferior to fish fed natural zooplankton. Two experiments were conducted in order to identify the underlying factors for this phenomenon. In the first experiment (Exp-1), groups of cod larvae were fed either (a) natural zooplankton, mainly copepods, increasing the size of prey as the larvae grew or (b) enriched rotifers followed by Artemia (the intensive group). In the second experiment (Exp-2), two groups of larvae were fed as in Exp-1, while a third group was fed copepod nauplii (approximately the size of rotifers) throughout the larval stage. In both experiments, growth was not significantly different between the groups during the first three weeks after hatching, but from the last part of the rotifer feeding period and onwards, the growth of the larvae fed copepods was higher than that of the intensive group. In Exp-2, the growth was similar between the two copepod groups during the expeimental period, indicating that nutrient composition, not prey size caused the better growth on copepods. Analyses of the prey showed that total fatty acid composition and the ratio of phospholipids to total lipids was slightly different in the prey organisms, and that protein, taurine, astaxanthin and zinc were lower on a dry weight basis in rotifers than in copepods. Other measured nutrients as DHA, all analysed vitamins, manganese, copper and selenium were similar or higher in the rotifers. When compared to the present knowledge on nutrient requirements, protein and taurine appeared to be the most likely limiting nutrients for growth in cod larvae fed rotifers and Artemia. Larvae fed rotifers/Artemia had a higher whole body lipid content than larvae fed copepods at the end of the experiment (stage 5) after the fish had been fed the same formulated diet for approximately 2 weeks. PMID:26038712

  14. Kinetic properties and heme pocket structure of two domains of the polymeric hemoglobin of Artemia in comparison with the native molecule.

    PubMed

    Borhani, Heshmat Akbari; Berghmans, Herald; Trashin, Stanislav; De Wael, Karolien; Fago, Angela; Moens, Luc; Habibi-Rezaei, Mehran; Dewilde, Sylvia

    2015-10-01

    In this project, we studied some physicochemical properties of two different globin domains of the polymeric hemoglobin of the brine shrimp Artemia salina and compared them with those of the native molecule. Two domains (AsHbC1D1 and AsHbC1D5) were cloned and expressed in BL21(DE3)pLysS strain of Escherichia coli. The recombinant proteins as well as the native hemoglobin (AfHb) were purified from bacteria and frozen Artemia, respectively by standard chromatographic methods and assessed by SDS-PAGE. The heme environment of these proteins was studied by optical spectroscopy and ligand-binding kinetics (e.g. CO association and O2 binding affinity) were measured for the two recombinant proteins and the native hemoglobin. This indicates that the CO association rate for AsHbC1D1 is higher than that of AsHbC1D5 and AfHb, while the calculated P50 value for AsHbC1D1 is lower than that of AsHbC1D5 and AfHb. The geminate and bimolecular rebinding parameters indicate a significant difference between both domains. Moreover, EPR results showed that the heme pocket in AfHb is in a more closed conformation than the heme pocket in myoglobin. Finally, the reduction potential of -0.13V versus the standard hydrogen electrode was determined for AfHb by direct electrochemical measurements. It is about 0.06V higher than the potential of the single domain AsHbC1D5. This work shows that each domain in the hemoglobin of Artemia has different characteristics of ligand binding. PMID:26004089

  15. Kinetic properties and heme pocket structure of two domains of the polymeric hemoglobin of Artemia in comparison with the native molecule.

    PubMed

    Borhani, Heshmat Akbari; Berghmans, Herald; Trashin, Stanislav; De Wael, Karolien; Fago, Angela; Moens, Luc; Habibi-Rezaei, Mehran; Dewilde, Sylvia

    2015-10-01

    In this project, we studied some physicochemical properties of two different globin domains of the polymeric hemoglobin of the brine shrimp Artemia salina and compared them with those of the native molecule. Two domains (AsHbC1D1 and AsHbC1D5) were cloned and expressed in BL21(DE3)pLysS strain of Escherichia coli. The recombinant proteins as well as the native hemoglobin (AfHb) were purified from bacteria and frozen Artemia, respectively by standard chromatographic methods and assessed by SDS-PAGE. The heme environment of these proteins was studied by optical spectroscopy and ligand-binding kinetics (e.g. CO association and O2 binding affinity) were measured for the two recombinant proteins and the native hemoglobin. This indicates that the CO association rate for AsHbC1D1 is higher than that of AsHbC1D5 and AfHb, while the calculated P50 value for AsHbC1D1 is lower than that of AsHbC1D5 and AfHb. The geminate and bimolecular rebinding parameters indicate a significant difference between both domains. Moreover, EPR results showed that the heme pocket in AfHb is in a more closed conformation than the heme pocket in myoglobin. Finally, the reduction potential of -0.13V versus the standard hydrogen electrode was determined for AfHb by direct electrochemical measurements. It is about 0.06V higher than the potential of the single domain AsHbC1D5. This work shows that each domain in the hemoglobin of Artemia has different characteristics of ligand binding.

  16. Ametabolic embryos of Artemia franciscana accumulate DNA damage during prolonged anoxia.

    PubMed

    McLennan, Alexander G

    2009-03-01

    Encysted embryos of the brine shrimp Artemia franciscana are able to survive prolonged periods of anoxia even when fully hydrated. During this time there is no metabolism, raising the question of how embryos tolerate spontaneous, hydrolytic DNA damage such as depurination. When incubated at 28 degrees C and 40 degrees C for several weeks, hydrated anoxic embryos were found to accumulate abasic sites in their DNA with k=5.8x10(-11) s(-1) and 2.8x10(-10) s(-1), respectively. In both cases this is about 3-fold slower than expected from published observations on purified DNA. However, purified calf thymus DNA incubated under similar anoxic conditions at pH 6.3, the intracellular pH of anoxic cysts, also depurinated more slowly than predicted (about 1.7-fold), suggesting that cysts may in fact accumulate abasic sites only slightly more slowly than purified DNA. Upon reoxygenation of cysts stored under N(2) for 30 weeks at 28 degrees C, the number of abasic sites per 10(4) bp DNA fell from 21.1+/-4.0 to 9.8+/-2.0 by 12 h and to 6.2+/-2.1 by 24 h. Larvae hatched after 48 h and 72 h had only 0.59+/-0.17 and 0.48+/-0.07 abasic sites per 10(4) bp, respectively, suggesting that repair of these lesions had largely taken place before hatching commenced. Thus, unlike bacterial spores, Artemia cysts appear to have no specific protective mechanism beyond what might be afforded by chromatin structure to limit spontaneous depurination, and rely on the repair of accumulated lesions during the period between reoxygenation and hatching. PMID:19251993

  17. Impact of brine acidification on hatchability, survival and reproduction of Artemia parthenogenetica and Artemia franciscana in salt ponds, Bohai Bay, China

    NASA Astrophysics Data System (ADS)

    Sui, Liying; Deng, Yuangao; Wang, Jing; Sorgeloos, Patrick; Van Stappen, Gilbert

    2014-01-01

    We studied the effect of pH (pH 5, 6, 7 and 8) on the hatching percentage, survival and reproduction of Artemia strains in Bohai Bay salt ponds. Strains included parthenogenetic Artemia from Bohai Bay (BHB), Artemia franciscana from San Francisco Bay, and A. franciscana artificially produced in salt ponds in Vietnam. The latter was included as a potential inoculum for biological management of salt ponds. The hatching percentage of cysts after 24 h and the survival rate of the tested Artemia strains were significantly reduced when exposed to a culture medium at pH 5 for 18 d ( P<0.05). The tolerance of Artemia to 48 h acid exposure varied with developmental stage, increasing in the following order: juvenile, nauplii, pre-adult, with maximum tolerance in adults. All strains of Artemia tested could not reproduce at pH 5. At pH levels from pH 6-8, a higher pH generally resulted in a shorter brood interval and enhanced ovoviviparity. Hence, we suggest that brine acidification has a negative impact on Artemia populations in the Bohai Bay saltworks. Inoculation of Artemia with either local parthenogenetic Artemia or exotic A. franciscana should be feasible at pH 7-8.

  18. Effects of calanoid copepod Schmackeria poplesia as a live food on the growth, survival and fatty acid composition of larvae and juveniles of Japanese flounder, Paralichthys olivaceus

    NASA Astrophysics Data System (ADS)

    Liu, Guangxing; Xu, Donghui

    2009-12-01

    Zooplankton constitutes a major part of the diet for fish larvae in the marine food web, and it is generally believed that copepods can meet the nutritional requirements of fish larvae. In this study, calanoid copepod Schmackeria poplesia, rotifer Brachionus plicatilis and anostraca crustacean Artemia sp. were analyzed for fatty acid contents, and were used as live food for culturing larval Japanese flounder, Paralichthys olivaceus. The total content of three types of HUFAs (DHA, EPA and ARA) in S. poplesia was significantly higher than that in the other two live foods ( P<0.01). Three live organisms were used for raising larvae and juveniles of Paralichthys olivaceus respectively for 15 and 10 d. Then the growth, survival and fatty acid composition of the larvae and juveniles were investigated. The results showed that the larvae and juveniles fed with copepods ( S. poplesia) had significantly higher growth rate than those fed with the other two organisms ( P<0.01). The survival of the flounder larvae fed with copepods was significantly higher than that of the others ( P<0.01), and the survival of the juvenile fish fed with copepods was higher than that fed with Artemia ( P<0.05). The contents of three types of HUFAs (DHA, EPA and ARA) and the ratio of DHA/EPA in larval and juvenile flounder P. olivaceus were analyzed. The results showed that the contents of DHA, EPA and ARA in the larvae and juveniles fed with S. poplesia were higher than those fed with a mixed diet or Artemia only, and the ratio of EPA/ARA in larvae and juveniles of P. olivaceus fed with S. poplesia was lower than that in the case of feeding with a mixed diet or Artemia only. The present data showed that copepod is the best choice for feeding the larvae and juveniles of fish considering its effects on the survival, growth and nutrition composition of the fish.

  19. 19. REGIONAL MAP, SALINAS RIVER PROJECT, CAMP SAN LUIS OBISPO, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. REGIONAL MAP, SALINAS RIVER PROJECT, CAMP SAN LUIS OBISPO, IN CENTRAL PORTION OF SAN LUIS OBISPO, CALIFORNIA. Leeds Hill Barnard & Jewett - Consulting Engineers, February 1942. - Salinas River Project, Cuesta Tunnel, Southeast of U.S. 101, San Luis Obispo, San Luis Obispo County, CA

  20. 21. CHAINAGE FROM SALINAS DAM TO NORTH PORTAL, STATIONS. Leeds, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    21. CHAINAGE FROM SALINAS DAM TO NORTH PORTAL, STATIONS. Leeds, Hill, Barnard & Jewett drawing, no date, no number, title block partially obscured. - Salinas River Project, Cuesta Tunnel, Southeast of U.S. 101, San Luis Obispo, San Luis Obispo County, CA

  1. Groundwater recharge on east side soils of the Salinas Valley

    Technology Transfer Automated Retrieval System (TEKTRAN)

    After four years of drought, groundwater levels in the Salinas Valley are at historically low levels which threaten to adversely affect farming in the Salinas Valley. Given the prospect of a strong El Niño this coming winter, it seems prudent to plan to capture as much of the rainfall as possible to...

  2. Abundance of potentially pathogenic micro-organisms in Penaeus monodon larvae rearing systems in India.

    PubMed

    Vaseeharan, Baskaralingam; Ramasamy, Palaniappan

    2003-01-01

    Monodon baculovirls (MBV), external fouling organisms (EFO) and bacteria (especially Vibrio species) were monitored during 1996-1997 at nine different Penaeus monodon rearing hatcheries in India. Total cultivable heterotrophic bacteria, Vibrio-like-bacteria, presumptive Vibrio harveyi, Vibrio anguillarum, Vibrio vulnificus counts were determined from shrimp eggs, post larvae, rearing tank water, source sea water, feed (Artemia nauplii and microencapsulated feed). The MBV infected post larvae and their environment showed higher Vibrio-like-bacteria than uninfected post larvae. An overwhelming predominance of presumptive Vibrio harveyi and Vibrio anguillarum was observed in post larval rearing tank water, MBV infected and uninfected post larvae. Vibrio-like-bacteria in Artemia nauplii clearly showed the possible source of these pathogenic bacteria in the hatchery environments. Quantitative analysis of Vibrio-like-bacteria in hatcheries revealed that when the Vibrio-like-bacteria increases to 2 x 10(2) CFU mortality of the post larvae occurs. Abundance of these micro-organisms in hatchery samples indicated that they are opportunistic pathogens which can invade the shrimp tissue, subsequently cause disease when the post larvae were under stressful conditions.

  3. Water-quality investigation, Salinas River, California

    USGS Publications Warehouse

    Irwin, G.A.

    1976-01-01

    Concentrations of dissolved solids in the Salinas River, California, are variable and range from 164 to 494 milligrams per liter near Bradley and from 170 to 1,090 milligrams per liter near Spreckels. Higher concentrations near Spreckels are caused mainly by sewage inflow about 150 feet (50 meters) upstream. Concentrations of nitrogen, phosphorus, total organic carbon, selected trace elements, and pesticides also generally increase downstream from Pozo to Spreckels and are related to sewage effluent; however, high concentrations occur elsewhere in the river. Specific conductance and water discharge regression results indicate that relations were all significant at the 1-percent probability level at Paso Robles, Bradley, and Spreckels with the explained variance ranging from 66 to 74 percent. Concentations of nitrogen, phosphorus, total organic carbon, and trace elements are only infrequently related to water discharge. (Woodard-USGS)

  4. The induction and extraction of metallothioneins in Artemia

    NASA Astrophysics Data System (ADS)

    Chen, Bing-Liang; Chien, Paul K.

    1994-06-01

    A small amount of heavy metal binding protein, identified by BioRad Protein Assay, has been isolated from the adult brine shrimp, Artemia franciscanus. This protein has an apparent molecular weight between 6000 to 9000 dalton. a UV absorption peak at 260 instead of 280 nm like most proteins; and has high affinity towards binding with radioactive labeled109Cd. These characteristics are similar to that of metallothioneins reported for many vertebrate and invertebrate, marine and terrestrial animals. After the brine shrimp is exposed to a small amount of Cd2+ for 24 h, a large amount of metallothionein can be isolated, showing the inducibility of this detoxifying protein in the adult Artemia in a short period of time.

  5. Copepods enhance nutritional status, growth and development in Atlantic cod (Gadus morhua L.) larvae — can we identify the underlying factors?

    PubMed Central

    van der Meeren, Terje; Rønnestad, Ivar; Mangor-Jensen, Anders; Galloway, Trina F.; Kjørsvik, Elin; Hamre, Kristin

    2015-01-01

    The current commercial production protocols for Atlantic cod depend on enriched rotifers and Artemia during first-feeding, but development and growth remain inferior to fish fed natural zooplankton. Two experiments were conducted in order to identify the underlying factors for this phenomenon. In the first experiment (Exp-1), groups of cod larvae were fed either (a) natural zooplankton, mainly copepods, increasing the size of prey as the larvae grew or (b) enriched rotifers followed by Artemia (the intensive group). In the second experiment (Exp-2), two groups of larvae were fed as in Exp-1, while a third group was fed copepod nauplii (approximately the size of rotifers) throughout the larval stage. In both experiments, growth was not significantly different between the groups during the first three weeks after hatching, but from the last part of the rotifer feeding period and onwards, the growth of the larvae fed copepods was higher than that of the intensive group. In Exp-2, the growth was similar between the two copepod groups during the expeimental period, indicating that nutrient composition, not prey size caused the better growth on copepods. Analyses of the prey showed that total fatty acid composition and the ratio of phospholipids to total lipids was slightly different in the prey organisms, and that protein, taurine, astaxanthin and zinc were lower on a dry weight basis in rotifers than in copepods. Other measured nutrients as DHA, all analysed vitamins, manganese, copper and selenium were similar or higher in the rotifers. When compared to the present knowledge on nutrient requirements, protein and taurine appeared to be the most likely limiting nutrients for growth in cod larvae fed rotifers and Artemia. Larvae fed rotifers/Artemia had a higher whole body lipid content than larvae fed copepods at the end of the experiment (stage 5) after the fish had been fed the same formulated diet for approximately 2 weeks. PMID:26038712

  6. A novel model of early development in the brine shrimp, Artemia franciscana, and its use in assessing the effects of environmental variables on development, emergence, and hatching.

    PubMed

    Neumeyer, Courtney H; Gerlach, Jamie L; Ruggiero, Kristin M; Covi, Joseph A

    2015-03-01

    The brine shrimp, Artemia (Crustacea, Anostraca), is a zooplankton that is commonly used in both basic and applied research. Unfortunately, Artemia embryos are often cultured under conditions that alter early development, and reports based on these cultures oversimplify or fail to describe morphological phenotypes. This is due in part to the lack of a comprehensive developmental model that is applicable to observations of live specimens. The objective of this study was to build and test a descriptive model of post-diapause development in Artemia franciscana using observations made with a standard dissecting microscope. The working model presented is the first to comprehensively place all known "abnormal" embryonic and naupliar phenotypes within the context of a classic hatching profile. Contrary to previous reports, embryos and nauplii with aberrant phenotypes often recover and develop normally. Oval prenauplii may emerge as normal prenauplii (E2 stage). A delay of this transition leads to incomplete hatching or direct hatching of first instar larvae with a curved thoracoabdomen. When hatching is incomplete, retained cuticular remnants are shed during the next molt, and a "normal" second instar larva is produced. By differentiating between molting events and gross embryonic patterning in live embryos, this new model facilitates fine time-scale analyses of chemical and environmental impacts on early development. A small increase in salinity within what is commonly believed to be a permissive range (20‰-35‰) produced aberrant morphology by delaying emergence without slowing development. A similar effect was observed by decreasing culture density within a range commonly applied in toxicological studies. These findings clearly demonstrate that morphological data from end-point studies are highly dependent on the time points chosen. An alternate assessment method is proposed, and the potential impact of heavy metals, hexachlorobenzene, Mirex, and cis

  7. Molecular phylogenetics and asexuality in the brine shrimp Artemia.

    PubMed

    Baxevanis, Athanasios D; Kappas, Ilias; Abatzopoulos, Theodore J

    2006-09-01

    Explaining cases of long-term persistence of parthenogenesis has proven an arduous task for evolutionary biologists. Interpreting sexual-asexual interactions though has recently advanced owing to methodological design, increased taxon sampling and choice of model organisms. We inferred the phylogeny of Artemia, a halophilic branchiopod genus of sexual and parthenogenetic forms with cosmopolitan distribution, marked geographic patterns and ecological partitioning. Joint analysis of newly derived ITS1 sequences and 16S RFLP markers from global isolates indicates significant interspecific divergence as well as pronounced diversity for parthenogens, matching that of sexual ancestors. Maximum parsimony, maximum likelihood, and Bayesian methods were largely congruent in reconstructing the phylogeny of the genus. Given the current sampling, at least four independent origins of parthenogenesis are deduced. Molecular clock calibrations based on biogeographic landmarks indicate that the lineage leading to A. persimilis diverged from the common ancestor of all Artemia species between 80 and 90 MYA at the time of separation of Africa from South America, whereas parthenogenesis first appeared at least 3 MYA. Common mitochondrial DNA haplotypes delineate A. urmiana and A. tibetiana as possible maternal parents of several clonal lineages. A novel topological placement of A. franciscana as a sister clade to all Asian Artemia and parthenogenetic forms is proposed and also supported by ITS1 length and other existing data.

  8. [Composition of fat acids in three Mexican populations of Artemia franciscana from epicontinental waters].

    PubMed

    Malpica Sánchez, Aída; Castro Barrera, Thalía; Sandoval Trujillo, Horacio; Castro Mejía, Jorge; De Lara Andrade, Ramón; Castro Mejía, Germán

    2004-03-01

    In this paper is presented the percentage of fatty acids composition of three Artemia franciscana Mexican populations of epicontinentals waters; two are from natural environments (Coahuila and San Luis Potosf) and one (Texcoco) is a culture fed with Spirulina. Determination of fatty acids composition in each population, was performed by extraction of total lipid by the soxhlet method and the fatty acids methyl esters were determined by gas chromatography. The results show that Artemia of Texcoco contains the six fatty acids recommended for the culture of fish and crustaceans (16:0; 16:1; 18:1; 18:2w6; 18:3w3 and 20:5w3); Artemia from San Luis Potosi showed the poorest content in these acids and Artemia from Coahuila, although it showed a wide profile, it lacks the linolenic acid. When comparing results among the three populations with ecological data that have been published, it can be pointed out that the environment is decisive for this crustacean; Artemia from Texcoco fed with Spirulina showed the largest variety of fatty acids; the other two populations are wild, and lives in different habitats, Artemia of Coahuila is found in waters that are rich in sulfates and Artemia of San Luis Potosf lives in evaporation saltern ponds, built with stone blocks and therefore with scarce phytoplankton growth. Both Artemia populations showed deficiencies in essential fatty acids, mainly the last one.

  9. Continuous production of carotenoids from Dunaliella salina.

    PubMed

    Kleinegris, Dorinde M M; Janssen, Marcel; Brandenburg, Willem A; Wijffels, René H

    2011-03-01

    During the in situ extraction of β-carotene from Dunaliella salina, the causal relationship between carotenoid extraction and cell death indicated that cell growth and cell death should be at equilibrium for a continuous in situ extraction process. In a flat-panel photobioreactor that was operated as a turbidostat cell numbers of stressed cells were kept constant while attaining a continuous well-defined light-stress. In this way it was possible to study the balance between cell growth and cell death and determine whether both could be increased to reach higher volumetric productivities of carotenoids. In the two-phase system a volumetric productivity of 8.3 mg β-carotene L(RV)(-1)d(-1) was obtained. In situ extraction contributed only partly to this productivity. The major part came from net production of carotenoid-rich biomass, due to a high growth rate of the cells and subsequent dilution of the reactor. To reach equilibrium between cell growth and cell death, sparging rates of dodecane could have been increased. However, already at the applied sparging rate of 286 L(dod)L(RV)(-1)min(-1) emulsion formation of the dodecane in the aqueous phase appeared. In a turbidostat without in situ extraction a volumetric productivity of 13.5 mg β-caroteneL(RV)(-1)d(-1) was reached, solely based on the continuous production of carotenoid-rich biomass. PMID:22112908

  10. Continuous production of carotenoids from Dunaliella salina.

    PubMed

    Kleinegris, Dorinde M M; Janssen, Marcel; Brandenburg, Willem A; Wijffels, René H

    2011-03-01

    During the in situ extraction of β-carotene from Dunaliella salina, the causal relationship between carotenoid extraction and cell death indicated that cell growth and cell death should be at equilibrium for a continuous in situ extraction process. In a flat-panel photobioreactor that was operated as a turbidostat cell numbers of stressed cells were kept constant while attaining a continuous well-defined light-stress. In this way it was possible to study the balance between cell growth and cell death and determine whether both could be increased to reach higher volumetric productivities of carotenoids. In the two-phase system a volumetric productivity of 8.3 mg β-carotene L(RV)(-1)d(-1) was obtained. In situ extraction contributed only partly to this productivity. The major part came from net production of carotenoid-rich biomass, due to a high growth rate of the cells and subsequent dilution of the reactor. To reach equilibrium between cell growth and cell death, sparging rates of dodecane could have been increased. However, already at the applied sparging rate of 286 L(dod)L(RV)(-1)min(-1) emulsion formation of the dodecane in the aqueous phase appeared. In a turbidostat without in situ extraction a volumetric productivity of 13.5 mg β-caroteneL(RV)(-1)d(-1) was reached, solely based on the continuous production of carotenoid-rich biomass.

  11. Effect of Artemia franciscana on the removal of nickel by bioaccumulation.

    PubMed

    Devi, S Sujatha; Sethu, M; Priya, P Gomathi

    2014-01-01

    The present study evaluates the feasibility of using Artemia franciscana in reducing the Ni concentration of synthetic wastewater by the process of bioaccumulation. Metallothionein protein plays a key role in the uptake of nickel by Artemia. Artemia (Brine shrimp) was exposed to an initial nickel concentration of 40 mg/L. Gradual decrease of nickel was observed from 40 mg/L to 5 mg/L with a removal efficiency of 87.5%. The number of organisms were varied to determine the number for the maximum removal efficiency. Metallothionein protein in Artemia was estimated by the silver saturation method. The physical parameters such as pH were maintained in an alkaline condition of 9-10, temperature was maintained at room temperature and salinity at 30-35‰. These were found to be the optimal conditions for the survival and reduction of nickel by Artemia. PMID:24975411

  12. Stimulating effect of space flight factors on Artemia cysts: comparison with irradiation by gamma rays

    SciTech Connect

    Gaubin, Y.; Pianezzi, B.; Gasset, G.; Plannel, H.; Kovalev, E.E.

    1986-06-01

    The Artemia cyst, a gastrula in dormant state, is a very suitable material to investigate the individual effects of HZE cosmic particles. Monolayers of Artemia cysts, sandwiched with nuclear emulsions, flew aboard the Soviet biosatellite Cosmos 1129. The space flight stimulated the developmental capacity expressed by higher percentages of emergence, hatching, and alive nauplii at day 4-5. A greater mean life span was reported in Artemias developed from Artemia cysts hit by the cosmic heavy ions. On Earth, Artemia cysts were exposed to 1, 10, 100, 200 and 400 Gy of gamma (gamma) rays. A stimulating effect on developmental capacity was observed for 10 Gy; the mean life span was significantly increased for this dose. These results are discussed in comparison with previous investigations performed on Earth and in space.

  13. Isolation of TDA-producing Phaeobacter strains from sea bass larval rearing units and their probiotic effect against pathogenic Vibrio spp. in Artemia cultures.

    PubMed

    Grotkjær, Torben; Bentzon-Tilia, Mikkel; D'Alvise, Paul; Dourala, Nancy; Nielsen, Kristian Fog; Gram, Lone

    2016-05-01

    Fish-pathogenic Vibrio can cause large-scale crashes in marine larval rearing units and, since the use of antibiotics can result in bacterial antibiotic resistance, new strategies for disease prevention are needed. Roseobacter-clade bacteria from turbot larval rearing facilities can antagonize Vibrio anguillarum and reduce mortality in V. anguillarum-infected cod and turbot larvae. In this study, it was demonstrated that antagonistic Roseobacter-clade bacteria could be isolated from sea bass larval rearing units. In addition, it was shown that they not only antagonized V. anguillarum but also V. harveyi, which is the major bacterial pathogen in crustaceans and Mediterranean sea bass larvae cultures. Concomitantly, they significantly improved survival of V. harveyi-infected brine shrimp. 16S rRNA gene sequence homology identified the antagonists as Phaeobacter sp., and in silico DNA-DNA hybridization indicated that they could belong to a new species. The genomes contained genes involved in synthesis of the antibacterial compound tropodithietic acid (TDA), and its production was confirmed by UHPLC-TOFMS. The new Phaeobacter colonized live feed (Artemia) cultures and reduced Vibrio counts significantly, since they reached only 10(4)CFUmL(-1), as opposed to 10(8)CFUmL(-1) in non-Phaeobacter treated controls. Survival of V. anguillarum-challenged Artemia nauplii was enhanced by the presence of wild type Phaeobacter compared to challenged control cultures (89±1.0% vs 8±3.2%). In conclusion, TDA-producing Phaeobacter isolated from Mediterranean marine larviculture are promising probiotic bacteria against pathogenic Vibrio in crustacean live-feed cultures for marine fish larvae. PMID:26922490

  14. Quantitative proteomic analysis of Dunaliella salina upon acute arsenate exposure.

    PubMed

    Ge, Ying; Ning, Zhibin; Wang, Ya; Zheng, Yanheng; Zhang, Chunhua; Figeys, Daniel

    2016-02-01

    Dunaliella salina is resistant to arsenic (As) and can accumulate a large amount of this highly toxic metalloid in cells. To study the mechanisms of As tolerance, a label-free, LC-MS/MS-based proteomic approach was applied for the first time to identify and quantify differentially expressed proteins from D. salina exposed to 11.2 mg L(-1) arsenate (As(V)) for 72 h. The intracellular As content reached 19.8 mg kg(-1), leading to a significant increase of lipid peroxidation in cells and a 7.4% growth reduction of this microalga. Sixty-five proteins were differentially expressed (p < 0.05), with 45 significantly induced and 20 declined. These proteins were involved in energy metabolism, protein synthesis and folding, ROS scavenging and defense, phosphate transport and membrane trafficking, and amino acid synthesis. Taken together, this study provides novel insights on the As(V) detoxification in D. salina.

  15. Automixis in Artemia: solving a century-old controversy.

    PubMed

    Nougué, O; Rode, N O; Jabbour-Zahab, R; Ségard, A; Chevin, L-M; Haag, C R; Lenormand, T

    2015-12-01

    Parthenogenesis (reproduction through unfertilized eggs) encompasses a variety of reproduction modes with (automixis) or without (apomixis) meiosis. Different modes of automixis have very different genetic and evolutionary consequences but can be particularly difficult to tease apart. In this study, we propose a new method to discriminate different types of automixis from population-level genetic data. We apply this method to diploid Artemia parthenogenetica, a crustacean whose reproductive mode remains controversial despite a century of intensive cytogenetic observations. We focus on A. parthenogenetica from two western Mediterranean populations. We show that they are diploid and that markers remain heterozygous in cultures maintained up to ~36 generations in the laboratory. Moreover, parallel patterns of population-wide heterozygosity levels between the two natural populations strongly support the conclusion that diploid A. parthenogenetica reproduce by automictic parthenogenesis with central fusion and low, but nonzero recombination. This settles a century-old controversy on Artemia, and, more generally, suggests that many automictic organisms harbour steep within-chromosome gradients of heterozygosity due to a transition from clonal transmission in centromere-proximal regions to a form of inbreeding similar to self-fertilization in centromere-distal regions. Such systems therefore offer a new avenue for contrasting the genomic consequences of asexuality and inbreeding.

  16. Automixis in Artemia: solving a century-old controversy.

    PubMed

    Nougué, O; Rode, N O; Jabbour-Zahab, R; Ségard, A; Chevin, L-M; Haag, C R; Lenormand, T

    2015-12-01

    Parthenogenesis (reproduction through unfertilized eggs) encompasses a variety of reproduction modes with (automixis) or without (apomixis) meiosis. Different modes of automixis have very different genetic and evolutionary consequences but can be particularly difficult to tease apart. In this study, we propose a new method to discriminate different types of automixis from population-level genetic data. We apply this method to diploid Artemia parthenogenetica, a crustacean whose reproductive mode remains controversial despite a century of intensive cytogenetic observations. We focus on A. parthenogenetica from two western Mediterranean populations. We show that they are diploid and that markers remain heterozygous in cultures maintained up to ~36 generations in the laboratory. Moreover, parallel patterns of population-wide heterozygosity levels between the two natural populations strongly support the conclusion that diploid A. parthenogenetica reproduce by automictic parthenogenesis with central fusion and low, but nonzero recombination. This settles a century-old controversy on Artemia, and, more generally, suggests that many automictic organisms harbour steep within-chromosome gradients of heterozygosity due to a transition from clonal transmission in centromere-proximal regions to a form of inbreeding similar to self-fertilization in centromere-distal regions. Such systems therefore offer a new avenue for contrasting the genomic consequences of asexuality and inbreeding. PMID:26356354

  17. Molecular identification of microorganisms associated with the brine shrimp Artemia franciscana

    PubMed Central

    2013-01-01

    Background Prior research on the microorganisms associated with the brine shrimp, Artemia franciscana, has mainly been limited to culture-based identification techniques or feeding studies for aquaculture. Our objective was to identify bacteria and archaea associated with Artemia adults and encysted embryos to understand the role of microbes in the Artemia life cycle and, therefore, their importance in a hypersaline food chain. Results We used small subunit (SSU) 16S ribosomal RNA gene sequencing to identify bacteria and archaea associated with adults and encysted Artemia embryos from one of their natural environments – Great Salt Lake (GSL), Utah, USA. We found that bacterial sequences most closely related to the genera Halomonas and Vibrio were commonly extracted from GSL adult Artemia, while bacterial sequences most similar to the genera Halomonas, Psychroflexus and Alkalilimnicola dominate in GSL water. Encysted embryos (cysts) yielded bacterial sequences from the genera Idiomarina and Salinivibrio, which were absent from adults and water. Common archaeal sequences in adults were most closely related to the genera Haloterrigena and Haloarcula, while all of the archaeal sequences from GSL water were most similar to the genus Halogeometricum. Cyst derived archaeal sequences were most closely related to the genera Halorubrum and Haloarcula. Conclusions In addition to identifying microbial rRNA sequences that are specific to different stages of the Artemia life cycle, we observed striking differences in the sequences associated with the adult Artemia population in samples collected from GSL at different times and locations. While our study was limited in scope and the sample was small, our findings provide a foundation for future research into how the bacteria and archaea associated with Artemia influence the Artemia life cycle, and GSL food web. PMID:23497541

  18. Diffusive properties of water in Artemia cysts as determined from quasi-elastic neutron scattering spectra. [Artemia shrimp

    SciTech Connect

    Trantham, E.C.; Rorschach, H.E.; Clegg, J.S.; Hazlewood, C.F.; Nicklow, R.M.; Wakabayashi, N.

    1984-05-01

    Results have been obtained on the quasi-elastic spectra of neutrons scattered from pure water, 20% agarose gel (hydration four grams H/sub 2/O per gram of dry solid) and cysts of the brine shrimp Artemia for hydrations between 0.10 and 1.2 grams H/sub 2/O per gram of dry solids. The spectra were interpreted using a two-component model that included contributions from the covalently bonded protons and the hydration water, and a mobile water fraction. The mobile fraction was described by a jump-diffusion correlation function for the translation motion and a simple diffusive orientational correlation function. The results for the line widths ..gamma..(Q/sup 2/) for pure water were in good agreement with previous measurements. The agarose results were consistent with NMR measurements that show a slightly reduced translational diffusion for the mobile water fraction. The Artemia results show that the translational diffusion coefficient of the mobile water fraction was greatly reduced from that of pure water. The line width was determined mainly by the rotational motion, which was also substantially reduced from the pure water value as determined from dielectric relaxation studies. The translational and rotational diffusion parameters were consistent with the NMR measurements of diffusion and relaxation. Values for the hydration fraction and the mean square thermal displacement as determined from the Q-dependence of line areas were also obtained.

  19. Mercury accumulation and its effects an Artemia franciscana

    SciTech Connect

    Boia, C.M.; Duarte, A.C.

    1995-12-31

    The effects of mercury accumulation on the brine shrimp Artemia franciscona were studied by long term (1--2 months) laboratory bioassays, using mercury chloride as the contaminant and the algae, Tetraselmis suecica as the food. These experiments were part of a larger research project aiming to contribute to the knowledge on mercury accumulation and its effects on Artemia. This crustacean is used worldwide for marine species feeding in aquafarms. This also happens on the lagoon of Aveiro, Portugal, which is partially contaminated with mercury. The first assays were conducted with concentrations of HgCl{sub 2} of the order of magnitude of those found in the waters of the lagoon of Aveiro (1.4 and 2.8 {micro}g/l). In further bioassays ranges of concentrations with observable effects have been used, from 0.02 to 1 mo. In the different assays the HgCl{sub 2} was: (a) simultaneously added to all the tanks or along the time, to evaluate the effects over different life stages (b) added directly to the tanks and then to the algae, at the same or in different quantities, to find out which was the more important pathway of contamination (c) removed from the feed stream after a certain time, to find out if detoxification would occur. The bioassays were carried out in five 100 l tanks under controlled temperature, pH, dissolved oxygen, salinity and feeding rate. Besides the content in mercury, size and number of the organisms have also been measured, as well as their content in total proteins, carbohydrates and fats.

  20. Assessment of fluorescent-labeled bacteria for evaluation of in vivo uptake of bacteria (Vibrio spp.) by crustacean larvae.

    PubMed

    Soto-Rodriguez, S A; Simões, N; Jones, D A; Roque, A; Gomez-Gil, B

    2003-01-01

    Available methods to study crustacean digestive tract colonization by bacteria are laborious, time-consuming, and do not permit in vivo assays and observation. This paper reports on a rapid and consistent technique to apply a fluorescent label to bacteria, which can then be presented to filter-feeding crustacea such as Artemia and penaeid larvae for later in situ bacterial distribution observation. Three luminescent Vibrio spp. were stained and observed inside Artemia nauplii, shrimp zoea and mysis stages, Vibrio harveyi type strain ATCC 14126, M(1) (pathogenic) and Ea (non-pathogenic). Factors such as dye (DTAF) concentration, exposure time/temperature and sonication time were evaluated. Viability of the dye and stained bacteria were tested at 4, -20 and -70 degrees C storage temperatures for up to 81 days. Results show that 4 and -20 degrees C storage temperatures are not recommended. At -70 degrees C, both bacteria and dye are optimally preserved. Monodispersed fluorescent-labeled bacterial cells can be observed inside the digestive tract of crustacean larvae at a density of inoculation as high as 5.2 x 10(6) CFU ml(-1). After 2 to 4 h, some leaching occurs, increasing difficulty in observation, although after 24 h, it is still possible to observe monodispersed FLB inside the digestive tract of crustacean larvae. Autofluorescence may complicate observation when filter-feeding crustacean larvae are co-fed with microalgae. PMID:12401232

  1. [Effects of initial feeding on the growth, survival, and body biochemical composition of Siberian sturgeon (Acipenser baerii) larvae].

    PubMed

    Zhang, Tao; Zhuang, Ping; Zhang, Long-Zhen; Wang, Bin; Gao, Lu-Jiao; Xia, Yong-Tao; Tian, Mei-Ping

    2009-02-01

    Siberian sturgeon (Acipenser baerii) larvae were raised with Limnodrilus sp., Artemia nauplii, Moina sp., and artificial commercial diet for 30 days to investigate the effects of different initial feeding diets on the growth, survival, and body biochemical composition of the larvae. The results showed that A. nauplii was the best initial feeding diet, with the survival rate of A. baerii larvae being significant higher (96.67%) than the others. Feeding with Limnodrilus sp. gave the highest growth rate of A. baerii larvae, while feeding with artificial commercial diet gave the lowest efficiency on the growth rate and survival rate of the larvae. The larvae raised with different diets had significantly different body biochemical composition. After fed with artificial commercial diet, the larvae had the highest moisture content but the lowest crude protein and crude ash contents. Taking A. nauplii as the initial feeding diet and then feeding with Limnodrilus sp. could gave the ideal growth and survival rates of A. baerii larvae. PMID:19459376

  2. Longitudinal Analysis of Microbiota in Microalga Nannochloropsis salina Cultures.

    PubMed

    Geng, Haifeng; Sale, Kenneth L; Tran-Gyamfi, Mary Bao; Lane, Todd W; Yu, Eizadora T

    2016-07-01

    Large-scale open microalgae cultivation has tremendous potential to make a significant contribution to replacing petroleum-based fuels with biofuels. Open algal cultures are unavoidably inhabited with a diversity of microbes that live on, influence, and shape the fate of these ecosystems. However, there is little understanding of the resilience and stability of the microbial communities in engineered semicontinuous algal systems. To evaluate the dynamics and resilience of the microbial communities in microalgae biofuel cultures, we conducted a longitudinal study on open systems to compare the temporal profiles of the microbiota from two multigenerational algal cohorts, which include one seeded with the microbiota from an in-house culture and the other exogenously seeded with a natural-occurring consortia of bacterial species harvested from the Pacific Ocean. From these month-long, semicontinuous open microalga Nannochloropsis salina cultures, we sequenced a time-series of 46 samples, yielding 8804 operational taxonomic units derived from 9,160,076 high-quality partial 16S rRNA sequences. We provide quantitative evidence that clearly illustrates the development of microbial community is associated with microbiota ancestry. In addition, N. salina growth phases were linked with distinct changes in microbial phylotypes. Alteromonadeles dominated the community in the N. salina exponential phase whereas Alphaproteobacteria and Flavobacteriia were more prevalent in the stationary phase. We also demonstrate that the N. salina-associated microbial community in open cultures is diverse, resilient, and dynamic in response to environmental perturbations. This knowledge has general implications for developing and testing design principles of cultivated algal systems. PMID:26956183

  3. Celestite replacements of evaporites in the Salina Group

    NASA Astrophysics Data System (ADS)

    Carlson, Ernest H.

    1987-09-01

    Replacements of evaporites by celestite were discovered recently at three sites in northwestern Ohio. These replacements are more durable than the original evaporites and provide new paleoenvironmental data for the upper Silurian rocks of the region. The occurrences are situated along the western margin of the Ohio (Cayugan) Basin and appear in the Greenfield Dolomite and in undifferentiated Salina dolostones. The replacements include: lenticular and prismatic crystals of gypsum, nodules of anhydrite and laminar evaporites. The lenticular crystals contain inclusions of carbonate and anhydrite, and are believed to have altered to anhydrite prior to replacement. The prismatic crystals are exceptionally well-preserved, with euhedral, deeply embayed outlines and internally zoned growth bands containing large numbers of inclusions of dolostone and anhydrite. Optical data for the latter crystals indicate that they are oriented replacements of gypsum, and suggest that the original gypsum was unchanged prior to replacement. The nodular and laminar occurrences display features such as chicken-wire and enterolithic structures, and were comprised of anhydrite prior to replacement. Replacement postdates the dolomitization and cementation of the Salina sediments enclosing the evaporites, but occurred prior to deep burial. The rocks hosting the replacements, therefore, did not provide the strontium. The strontium may have been released from dolomitization of the underlying Lockport (Niagaran) beds or from dissolution of subaerially exposed Salina gypsum prior to the middle Devonian.

  4. Dunaliella salina as a novel host for the production of recombinant proteins.

    PubMed

    Feng, Shuying; Li, Xuebing; Xu, Zhengshun; Qi, Jingjiao

    2014-05-01

    Although several expression systems are currently available for the production of recombinant proteins, they still have some inherent disadvantages, thereby resulting in the desire to explore a novel expression system for producing recombinant proteins. Dunaliella salina (D. salina) has been exploited as a novel expression system for the field of genetic engineering because of its distinct advantages, including low production cost, fast growth, easy culture, ease of transgenic manipulation, and modified abilities of transcription and translation. Thus far, studies on D. salina host have made great development and significant progress. This paper presents a comprehensive summary of the achievements of D. salina host from the following aspects: the advantages of D. salina cells, transformation methods, cloning of D. salina genes, and expression of exogenous genes into D. salina. Furthermore, the authors identified the current main obstacles and future application prospects for the recombinant proteins produced by D. salina, which could be used as a basis for the future maturation of D. salina expression system. PMID:24643734

  5. Dunaliella salina as a novel host for the production of recombinant proteins.

    PubMed

    Feng, Shuying; Li, Xuebing; Xu, Zhengshun; Qi, Jingjiao

    2014-05-01

    Although several expression systems are currently available for the production of recombinant proteins, they still have some inherent disadvantages, thereby resulting in the desire to explore a novel expression system for producing recombinant proteins. Dunaliella salina (D. salina) has been exploited as a novel expression system for the field of genetic engineering because of its distinct advantages, including low production cost, fast growth, easy culture, ease of transgenic manipulation, and modified abilities of transcription and translation. Thus far, studies on D. salina host have made great development and significant progress. This paper presents a comprehensive summary of the achievements of D. salina host from the following aspects: the advantages of D. salina cells, transformation methods, cloning of D. salina genes, and expression of exogenous genes into D. salina. Furthermore, the authors identified the current main obstacles and future application prospects for the recombinant proteins produced by D. salina, which could be used as a basis for the future maturation of D. salina expression system.

  6. Historical Ground-Water Development in the Salinas Alluvial Fan Area, Salinas, Puerto Rico, 1900-2005

    USGS Publications Warehouse

    Rodriguez, Jose M.; Gómez-Gómez, Fernando

    2008-01-01

    The Salinas alluvial fan area has historically been one of the most intensively used agricultural areas in the South Coastal Plain of Puerto Rico. Changes in agricultural practices and land use in the Salinas alluvial fan have also caused changes in the geographic distribution of ground-water withdrawals from the alluvial aquifer. As a result, the ground-water balance and ground-water flow pattern have changed throughout the years and may explain the presence of saline ground water along parts of the coast at present. By providing a reconstruction of historical ground-water development in the Salinas alluvial fan area, from the initial years of aquifer development at about 1900 to the most recent conditions existing in 2005, water resources managers and planners can use the results of the analysis for a more complete understanding of aquifer conditions especially pertaining to water quality. This study effort was conducted by the U.S. Geological Survey in cooperation with the Puerto Rico Department of Natural and Environmental Resources as a contribution in the management of the Jobos Bay National Estuarine Research Reserve. The study area encompasses about 20 mi2 (square miles) of the extensive South Coastal Plain alluvial aquifer system (fig. 1). The study area is bounded to the north by foothills of the Cordillera Central mountain chain, to the south by the Caribbean Sea, and to the east and west by the Rio Nigua de Salinas and the Quebrada Aguas Verdes, respectively. Fan-delta and alluvial deposits contain the principal aquifers in the study area.

  7. Gamma Radiation Reduced Toxicity of Azoxystrobin Tested on Artemia franciscana.

    PubMed

    Dvorak, P; Zdarsky, M; Benova, K; Falis, M; Tomko, M

    2016-06-01

    Fungicide azoxystrobin toxicity was monitored by means of a 96-h biotest with Artemia franciscana nauplius stages after exposure to solutions with concentrations of 0.2, 0.4, 0.6 and 0.8 mg L(-1) irradiated with (60)Co gamma radiation with doses of 1, 2.5, 5 and 10 kGy. The effects of ionization radiation on azoxystrobin toxicity were mainly manifested by a statistically significant reduction of lethality after 72- and 96-h exposure. A maximum reduction of lethality of 72 % was achieved using doses of 1-5 kGy for an azoxystrobin initial concentration of 0.4 mg L(-1) and after 72 h of exposure. At a 96-h exposure, a difference of lethal effects reached up to 70 % for a dose of 10 kGy. The observed effect of gamma ionizing radiation on azoxystrobin toxicity suggest that this approach can be applied as an alternative for a reduction of azoxystrobin residua in food. PMID:27107585

  8. Artemia parthenogenetica (Branchiopoda: Anostraca) from the Large Aral Sea: Abundance, distribution, population structure and cyst production

    NASA Astrophysics Data System (ADS)

    Arashkevich, Elena G.; Sapozhnikov, P. V.; Soloviov, K. A.; Kudyshkin, T. V.; Zavialov, P. O.

    2009-03-01

    The brine shrimp Artemia parthenogenetica appeared in the Large Aral Sea (Central Asia) in 1998 when mineralization reached 63 ppt. Data on Artemia abundance and biomass, along with temperature and salinity measurements were collected in the western basin during 2002-2006, primarily in the autumn. During the study period, population density grew progressively, both in terms of number, from 250 to 1260 individuals per m 3, and in terms of biomass, from 0.3 to 1.3 g per m 3. In 2005, the population density and spatial distribution in the different parts of the sea (western and eastern basins and strait) was assessed. The horizontal distribution of the Artemia population was uniform in the deep central part of the western basin, although the distribution was quite patchy in the shallow coastal zone. Depth habitat of Artemia was restricted to the upper 20-25 m of depth, as the oxygen depletion and formation of anoxic layer prevented distribution of Artemia to the deeper waters. In autumn, all females reproduced oviparously, with an average clutch size of 30-35 eggs per female. The number of eggs in a clutch was positively correlated with female body length ( r2 = 0.36-0.44).

  9. Stress tolerance during diapause and quiescence of the brine shrimp, Artemia.

    PubMed

    MacRae, Thomas H

    2016-01-01

    Oviparously developing embryos of the brine shrimp, Artemia, arrest at gastrulation and are released from females as cysts before entering diapause, a state of dormancy and stress tolerance. Diapause is terminated by an external signal, and growth resumes if conditions are permissible. However, if circumstances are unfavorable, cysts enter quiescence, a dormant stage that continues as long as adverse conditions persist. Artemia embryos in diapause and quiescence are remarkably resistant to environmental and physiological stressors, withstanding desiccation, cold, heat, oxidation, ultraviolet radiation, and years of anoxia at ambient temperature when fully hydrated. Cysts have adapted to stress in several ways; they are surrounded by a rigid cell wall impermeable to most chemical compounds and which functions as a shield against ultraviolet radiation. Artemia cysts contain large amounts of trehalose, a non-reducing sugar thought to preserve membranes and proteins during desiccation by replacing water molecules and/or contributing to vitrification. Late embryogenesis abundant proteins similar to those in seeds and other anhydrobiotic organisms are found in cysts, and they safeguard cell organelles and proteins during desiccation. Artemia cysts contain abundant amounts of p26, a small heat shock protein, and artemin, a ferritin homologue, both ATP-independent molecular chaperones important in stress tolerance. The evidence provided in this review supports the conclusion that it is the interplay of these protective elements that make Artemia one of the most stress tolerant of all metazoan organisms. PMID:26334984

  10. Assessment of the production potential of an emerging Artemia population in the Aral Sea, Uzbekistan

    NASA Astrophysics Data System (ADS)

    Marden, Brad; Van Stappen, Gilbert; Musaev, Ablatdyin; Mirabdullayev, Iskandar; Joldasova, Iliya; Sorgeloos, Patrick

    2012-04-01

    The objective of this study was to provide information on the developing parthenogenetic Artemia population in the Uzbek part of the Aral Sea, and to assess its potential for commercial exploitation. A sampling campaign was designed for abiotic factors (temperature, salinity, transparency) and Artemia population parameters at least once monthly in the period March-October of the years 2005-2007. By 2007 salinity in both basins had increased to values above 100 g l - 1 . Moreover, by 2007, desiccation had rendered the eastern Aral basin practically inaccessible for sampling or cyst harvesting. The volume of the western basin remained considerable, given its depth, with a relatively accessible shoreline. Average Artemia population parameters (e.g. adult abundance < 0.5 adults l - 1 ; 10-25 cysts brood - 1 ; cyst abundance < 5 and 10 cysts l - 1 for the western, resp. eastern basin) were low compared to Artemia sites of commercial importance. A gradual gain in population size in the western basin was observed over the period 2005-2007. The data further suggest that the low Artemia productivity is not genetically determined, but is largely the result of food limitation. The western basin may approach the threshold where a small-scale commercial operation is justified.

  11. Acute toxicity impacts of Euphorbia hirta L extract on behavior, organs body weight index and histopathology of organs of the mice and Artemia salina

    PubMed Central

    Rajeh, Mohammad Abu Basma; Kwan, Yuet Ping; Zakaria, Zuraini; Latha, Lachimanan Yoga; Jothy, Subramanion L.; Sasidharan, Sreenivasan

    2012-01-01

    Background: The methanol extract of Euphorbia hirta L (Euphorbiaceae), which is used in traditional medicines, was tested for in vivo toxicity. Materials and Methods: In vivo brine shrimp lethality assay and oral acute toxicity study at single high dose of 5000 mg/kg and observation for 14 days in mice were used to study the toxic effect of E. hirta. Results: Brine shrimp lethality assay was used to calculate the median lethal concentration (LC50) of E. hirta (for leaves, stems, flowers and roots) methanolic extracts at concentrations from 100 to 0.07 mg/ml. The LC50 values of 1.589, 1.420, 0.206 and 0.0827 mg/ml were obtained for stems, leaves, flowers and roots, respectively. Potassium dichromate (the positive control) had LC50 value of 0.00758 mg/ml. The acute oral toxicity study of the leaf extract resulted in one third mortality and mild behavioral changes among the treated mice. No significant statistical differences found between body weight, relative (%) and absolute (g) organ weights of treated and untreated groups (P> 0.05). Gross and microscopic examination of the vital organ tissues revealed no differences between control and treated mice. All the tissues appeared normal. Conclusions: E. hirta leaves methanol extract has exhibited mild toxic effects in mice. PMID:22923956

  12. Dietary fatty acid composition affects food intake and gut-brain satiety signaling in Senegalese sole (Solea senegalensis, Kaup 1858) larvae and post-larvae.

    PubMed

    Bonacic, Kruno; Campoverde, Cindy; Gómez-Arbonés, Javier; Gisbert, Enric; Estevez, Alicia; Morais, Sofia

    2016-03-01

    Little is known how dietary lipids affect food intake during larval development of fish, especially with regard to fatty acid (FA) composition. In fact, very little work has been done on appetite regulation and food intake in fish larvae in general, due to biological and technical difficulties associated with this type of studies. A new method using fluorescent microspheres as markers was developed in this study to evaluate food intake and prey selectivity of Senegalese sole larvae and post-larvae. Food intake was quantified in fish fed Artemia metanauplii enriched with oils differing in FA profile: cod liver oil (CLO), linseed oil (LSO), soybean oil (SBO) or olive oil (OO). The fish did not preferentially ingest a specific diet when presented with a choice. However, pre-metamorphic larvae from the CLO treatment ingested more metanauplii per g body weight, while differences in post-larvae were not significant. These findings were developed further by analyzing mRNA levels of a range of putative anorexigenic (pyya, pyyb, glp1, cckl, cart1a, cart1b, cart2a, cart4, pomca, pomcb, crf) and orexigenic (gal, npy, agrp2) genes, to identify those which are significantly affected by feeding and/or dietary FA composition. The variety of expression patterns observed highlighted the complexity of appetite regulatory mechanisms. In general, fish fed the CLO diet tended to show gene expression patterns most dissimilar to the remaining treatments. Expression in pre-metamorphic larvae was generally less in accordance with the putative function of the genes than in post-larvae, which could suggest a yet underdeveloped regulatory system.

  13. Dietary fatty acid composition affects food intake and gut-brain satiety signaling in Senegalese sole (Solea senegalensis, Kaup 1858) larvae and post-larvae.

    PubMed

    Bonacic, Kruno; Campoverde, Cindy; Gómez-Arbonés, Javier; Gisbert, Enric; Estevez, Alicia; Morais, Sofia

    2016-03-01

    Little is known how dietary lipids affect food intake during larval development of fish, especially with regard to fatty acid (FA) composition. In fact, very little work has been done on appetite regulation and food intake in fish larvae in general, due to biological and technical difficulties associated with this type of studies. A new method using fluorescent microspheres as markers was developed in this study to evaluate food intake and prey selectivity of Senegalese sole larvae and post-larvae. Food intake was quantified in fish fed Artemia metanauplii enriched with oils differing in FA profile: cod liver oil (CLO), linseed oil (LSO), soybean oil (SBO) or olive oil (OO). The fish did not preferentially ingest a specific diet when presented with a choice. However, pre-metamorphic larvae from the CLO treatment ingested more metanauplii per g body weight, while differences in post-larvae were not significant. These findings were developed further by analyzing mRNA levels of a range of putative anorexigenic (pyya, pyyb, glp1, cckl, cart1a, cart1b, cart2a, cart4, pomca, pomcb, crf) and orexigenic (gal, npy, agrp2) genes, to identify those which are significantly affected by feeding and/or dietary FA composition. The variety of expression patterns observed highlighted the complexity of appetite regulatory mechanisms. In general, fish fed the CLO diet tended to show gene expression patterns most dissimilar to the remaining treatments. Expression in pre-metamorphic larvae was generally less in accordance with the putative function of the genes than in post-larvae, which could suggest a yet underdeveloped regulatory system. PMID:26851305

  14. Methodical aspects of rearing decapod larvae, Pagurus bernhardus (Paguridae) and Carcinus maenas (Portunidae)

    NASA Astrophysics Data System (ADS)

    Dawirs, R. R.

    1982-12-01

    Improved methods for experimental rearing of Pagurus bernhardus and Carcinus maenas larvae are presented. Isolated maintenance was found essential for reliable statistical evaluation of results obtained from stages older than zoea-1. Only by isolated rearing is it possible to calculate mean values ±95% confidence intervals of stage duration. Mean values (without confidence intervals) can only be given for group-reared larvae if mortality is zero. Compared to group rearing, isolated rearing led to better survival, shorter periods of development and stimulated growth. Due to different swimming behavior P. bernhardus zoeae needed larger water volumes than Carcinus maenas larvae. P. bernhardus zoeae were reared with best results when isolated in Petri dishes (ca. 50 ml). They fed on newly hatched brine shrimp nauplii ( Artemia spp.). P. bernhardus megalopa did not require any gastropod shell or substratum; it developed best in glass vials without any food. C. maenas larvae could be reared most sucessfully in glass vials (ca 20 ml) under a simulated day-night regime (LD 16:8); constant darkness had a detrimental effect on development, leading to prolonged stage-duration times. C. maenas larvae were fed a mixture of newly hatched brine shrimp naupli and rotifers ( Brachionus plicatilis).

  15. Cestodes change the isotopic signature of brine shrimp, Artemia, hosts: implications for aquatic food webs.

    PubMed

    Sánchez, Marta I; Varo, Nico; Matesanz, Cristina; Ramo, Cristina; Amat, Juan A; Green, Andy J

    2013-01-01

    To reach the final host (greater flamingos), the cestode Flamingolepis liguloides alters the behaviour of its intermediate host, the brine shrimp, Artemia parthenogenetica, causing it to spend more time close to the water surface. During summer 2010, we showed that the prevalence of this cestode was consistently higher at the top of the water column in the Odiel salt pans in south-western Spain. We used stable nitrogen (N) and carbon (C) isotopic analysis to test the hypothesis that cestodes also alter resource use by Artemia. In early summer, we compared stable isotopes in infected hosts at the surface with those from uninfected hosts at the bottom of the water column. In late summer, we compared infected and uninfected Artemia from the bottom. δ(15)N was consistently enriched in infected individuals compared with uninfected hosts, especially in Artemia with multiple infections of F. liguloides (family Hymenolepididae) and those with mixed infections of F. liguloides and cestodes of the family Dilepididae. Infected individuals from the surface were enriched in δ(13)C compared with uninfected ones from the bottom, but the opposite was found when comparing uninfected and infected Artemia from the same depth. This may be caused by the increase in lipid concentration in infected Artemia. Isolated cysticercoids of F. liguloides were significantly enriched in δ(13)C compared with cysticercoids in infected hosts, but surprisingly were not enriched in N. Our findings illustrate the way cestodes can alter food webs and highlight the importance of considering the parasitic status of prey in studies of trophic ecology in saline wetlands.

  16. Dunaliella salina exhibits an antileukemic immunity in a mouse model of WEHI-3 leukemia cells.

    PubMed

    Chuang, Wen-Chen; Ho, Yung-Chyuan; Liao, Jiunn-Wang; Lu, Fung-Jou

    2014-11-26

    Dunaliella salina has been shown to have antioxidant property and induce apoptotic cell death of human cancer cells in vitro. However, there is no information available on D. salina showing an antileukemia effect or immunomodulatory activity in vivo. This study applied D. salina to syngeneic leukemia-implanted mice (BALB/c and WEHI-3) to investigate its immunological and antileukemia properties. Oral administration of D. salina (184.5, 369, and 922.5 mg/kg) inhibited spleen metastasis and prolonged the survival in BALB/c mice that had received an intravenous injection of WEHI-3 cells. The results revealed that D. salina had reduced spleen enlargement in murine leukemia. It had also increased the population and proliferation of T-cells (CD3) and B-cells (CD19) following Con A/LPS treatment on flow cytometry and MTT assay, respectively. Furthermore, D. salina increased the phagocytosis of macrophages and enhanced the cytotoxicity of natural killer cells on flow cytometry and LDH assay. Moreover, D. salina enhanced the levels of interferon-γ and interleukin 2 (IL-2) but reduced the levels of IL-4 and IL-10 in leukemic mice. In conclusion, these results demonstrated that the application of D. salina had beneficial effects on WEHI-3 leukemic mice by prolonging survival via modulating the immune responses.

  17. Multifractal anisotropic swimming: the optimal foraging behaviour of grouper larvae.

    PubMed

    Mahjoub, M S; Dur, G; Souissi, S; Schmitt, F G; Hwang, J S

    2016-05-01

    It was hypothesized that the Malabar grouper Ephinephelus malabaricus larvae have developed search patterns adapted to the distribution of their prey to maximise their net energy intake per unit time. Analysis of the swimming behaviour of E. malabaricus larvae in both the presence and absence of Artemia sp. nauplii is presented to test this hypothesis. A method derived from turbulence studies (the moment function of the displacements) was used to characterize the behaviour. The results revealed that larval swimming pattern was multifractal (intermittent and long-range-correlated) and isotropic (i.e. uniform in all directions) in the presence of prey, but multifractal and anisotropic (i.e. more frequent long displacement on the vertical axis) in the absence of prey. It is suggested that the search behaviour observed in the absence of prey is an adaptive response to prey distribution pattern, which is often characterised by multifractality and anisotropy (i.e. larger patches on the horizontal axes). In the presence of prey, E. malabaricus shifted to intensive search behaviour. Other possible contributors to the observed patterns are discussed. It is concluded that multifractality and anisotropy of swimming patterns observed in the experiment are mainly explained in an optimal foraging theory framework. PMID:27021375

  18. Development of the brine shrimp Artemia is accelerated during spaceflight

    NASA Technical Reports Server (NTRS)

    Spooner, B. S.; Metcalf, J.; DeBell, L.; Paulsen, A.; Noren, W.; Guikema, J. A.

    1994-01-01

    Developmentally arrested brine shrimp cysts have been reactivated during orbital spaceflight on two different Space Shuttle missions (STS-50 and STS-54), and their subsequent development has been compared with that of simultaneously reactivated ground controls. Flight and control brine shrimp do not significantly differ with respect to hatching rates or larval morphology at the scanning and transmission EM levels. A small percentage of the flight larvae had defective nauplier eye development, but the observation was not statistically significant. However, in three different experiments on two different flights, involving a total of 232 larvae that developed in space, a highly significant difference in degree of flight to control development was found. By as early as 2.25 days after reactivation of development, spaceflight brine shrimp were accelerated, by a full instar, over ground control brine shrimp. Although developing more rapidly, flight shrimp grew as long as control shrimp at each developmental instar or stage.

  19. Baylisascaris larva migrans

    USGS Publications Warehouse

    Kazacos, Kevin R.

    2016-01-01

    SummaryBaylisascaris procyonis, the common raccoon roundworm, is the most commonly recognized cause of clinical larva migrans (LM) in animals, a condition in which an immature parasitic worm or larva migrates in a host animal’s tissues, causing obvious disease. Infection with B. procyonis is best known as a cause of fatal or severe neurologic disease that results when the larvae invade the brain, the spinal cord, or both; this condition is known as neural larva migrans (NLM). Baylisascariasis is a zoonotic disease, that is, one that is transmissible from animals to humans. In humans, B. procyonis can cause damaging visceral (VLM), ocular (OLM), and neural larva migrans. Due to the ubiquity of infected raccoons around humans, there is considerable human exposure and risk of infection with this parasite. The remarkable disease-producing capability of B. procyonis in animals and humans is one of the most significant aspects of the biology of ascarids (large roundworms) to come to light in recent years. Infection with B. procyonis has important health implications for a wide variety of free-ranging and captive wildlife, zoo animals, domestic animals, as well as human beings, on both an individual and population level. This report, eighth in the series of U.S. Geological Survey Circulars on zoonotic diseases, will help us to better understand the routes of Baylisascaris procyonis infections and how best to adequately monitor this zoonotic disease.

  20. Baylisascaris larva migrans

    USGS Publications Warehouse

    Kazacos, Kevin R.; Abbott, Rachel C.; Van Riper, Charles

    2016-05-26

    SummaryBaylisascaris procyonis, the common raccoon roundworm, is the most commonly recognized cause of clinical larva migrans (LM) in animals, a condition in which an immature parasitic worm or larva migrates in a host animal’s tissues, causing obvious disease. Infection with B. procyonis is best known as a cause of fatal or severe neurologic disease that results when the larvae invade the brain, the spinal cord, or both; this condition is known as neural larva migrans (NLM). Baylisascariasis is a zoonotic disease, that is, one that is transmissible from animals to humans. In humans, B. procyonis can cause damaging visceral (VLM), ocular (OLM), and neural larva migrans. Due to the ubiquity of infected raccoons around humans, there is considerable human exposure and risk of infection with this parasite. The remarkable disease-producing capability of B. procyonis in animals and humans is one of the most significant aspects of the biology of ascarids (large roundworms) to come to light in recent years. Infection with B. procyonis has important health implications for a wide variety of free-ranging and captive wildlife, zoo animals, domestic animals, as well as human beings, on both an individual and population level. This report, eighth in the series of U.S. Geological Survey Circulars on zoonotic diseases, will help us to better understand the routes of Baylisascaris procyonis infections and how best to adequately monitor this zoonotic disease.

  1. Metabolic engineering of Dunaliella salina for production of ketocarotenoids.

    PubMed

    Anila, N; Simon, Daris P; Chandrashekar, Arun; Ravishankar, G A; Sarada, R

    2016-03-01

    Dunaliella is a commercially important marine alga producing high amount of β-carotene. The use of Dunaliella as a potential transgenic system for the production of recombinant proteins has been recently recognized. The present study reports for the first time the metabolic engineering of carotenoid biosynthesis in Dunaliella salina for ketocarotenoid production. The pathway modification included the introduction of a bkt gene from H. pluvialis encoding β-carotene ketolase (4,4'β-oxygenase) along with chloroplast targeting for the production of ketocarotenoids. The bkt under the control of Dunaliella Rubisco smaller subunit promoter along with its transit peptide sequence was introduced into the alga through standardized Agrobacterium-mediated transformation procedure. The selected transformants were confirmed using GFP and GUS expression, PCR and southern blot analysis. A notable upregulation of the endogenous hydroxylase level of transformants was observed where the BKT expression was higher in nutrient-limiting conditions. Carotenoid analysis of the transformants through HPLC and MS analysis showed the presence of astaxanthin and canthaxanthin with maximum content of 3.5 and 1.9 µg/g DW, respectively. The present study reports the feasibility of using D. salina for the production of ketocarotenoids including astaxanthin.

  2. Periodic CO2 Dosing Strategy for Dunaliella salina Batch Culture.

    PubMed

    Ying, Kezhen; Gilmour, D James; Zimmerman, William B

    2015-01-01

    A periodic CO2 dosing strategy for D. salina 19/30 batch culture is proposed. A model of periodic CO2 dosing including dosing time calculation, dosing interval estimation and final chlorophyll yield prediction was established. In experiments, 5% CO2/95% N2 gas was periodically dosed into D. salina culture. Two different gas dosing flow rates were tested. The corresponding dosing time for each flow rate was estimated via the model (10 min·d-1 for 0.7 L·min-1 and 36 min·d-1 for 0.3 L·min-1). Daily pH measurements showed that the pH of these cultures dosed periodically was always kept between 7.5 and 9.5, which highlights that periodic gas supply can maintain a suitable range of pH for microalgal growth without expensive buffers. Notably the culture dosed for set daily intervals was seen to have similar growth to the culture supplied constantly, but with much higher CO2 capture efficiency (11%-18%) compared to continuous dosing (0.25%). It shows great potential for using periodic gas supply to reduce cost, wasted gas and energy use.

  3. Metabolic engineering of Dunaliella salina for production of ketocarotenoids.

    PubMed

    Anila, N; Simon, Daris P; Chandrashekar, Arun; Ravishankar, G A; Sarada, R

    2016-03-01

    Dunaliella is a commercially important marine alga producing high amount of β-carotene. The use of Dunaliella as a potential transgenic system for the production of recombinant proteins has been recently recognized. The present study reports for the first time the metabolic engineering of carotenoid biosynthesis in Dunaliella salina for ketocarotenoid production. The pathway modification included the introduction of a bkt gene from H. pluvialis encoding β-carotene ketolase (4,4'β-oxygenase) along with chloroplast targeting for the production of ketocarotenoids. The bkt under the control of Dunaliella Rubisco smaller subunit promoter along with its transit peptide sequence was introduced into the alga through standardized Agrobacterium-mediated transformation procedure. The selected transformants were confirmed using GFP and GUS expression, PCR and southern blot analysis. A notable upregulation of the endogenous hydroxylase level of transformants was observed where the BKT expression was higher in nutrient-limiting conditions. Carotenoid analysis of the transformants through HPLC and MS analysis showed the presence of astaxanthin and canthaxanthin with maximum content of 3.5 and 1.9 µg/g DW, respectively. The present study reports the feasibility of using D. salina for the production of ketocarotenoids including astaxanthin. PMID:26334599

  4. The reaction of European lobster larvae (Homarus gammarus) to different quality food: effects of ontogenetic shifts and pre-feeding history.

    PubMed

    Schoo, Katherina L; Aberle, Nicole; Malzahn, Arne M; Schmalenbach, Isabel; Boersma, Maarten

    2014-02-01

    Young larval stages of many organisms represent bottlenecks in the life-history of many species. The high mortality commonly observed in, for example, decapod larvae has often been linked to poor nutrition, with most studies focussing on food quantity. Here, we focus instead on the effects of quality and have investigated its effects on the nutritional condition of lobster larvae. We established a tri-trophic food chain consisting of the cryptophyte Rhodomonas salina, the calanoid copepod Acartia tonsa and larvae of the European lobster Homarus gammarus. In a set of experiments, we manipulated the C:N:P stoichiometry of the primary producers, and accordingly those of the primary consumer. In a first experiment, R. salina was grown under N- and P-limitation and the nutrient content of the algae was manipulated by addition of the limiting nutrient to create a food quality gradient. In a second experiment, the effect on lobster larvae of long- and short-term exposure to food of varying quality during ontogenetic development was investigated. The condition of the lobster larvae was negatively affected even by subtle N- and P-nutrient limitations of the algae. Furthermore, younger lobster larvae were more vulnerable to nutrient limitation than older ones, suggesting an ontogenetic shift in the capacity of lobster larvae to cope with low quality food. The results presented here might have substantial consequences for the survival of lobster larvae in the field, as, in the light of future climate change and re-oligotrophication of the North Sea, lobster larvae might face marked changes in temperature and nutrient conditions, thus significantly altering their condition and growth. PMID:24072442

  5. The reaction of European lobster larvae (Homarus gammarus) to different quality food: effects of ontogenetic shifts and pre-feeding history.

    PubMed

    Schoo, Katherina L; Aberle, Nicole; Malzahn, Arne M; Schmalenbach, Isabel; Boersma, Maarten

    2014-02-01

    Young larval stages of many organisms represent bottlenecks in the life-history of many species. The high mortality commonly observed in, for example, decapod larvae has often been linked to poor nutrition, with most studies focussing on food quantity. Here, we focus instead on the effects of quality and have investigated its effects on the nutritional condition of lobster larvae. We established a tri-trophic food chain consisting of the cryptophyte Rhodomonas salina, the calanoid copepod Acartia tonsa and larvae of the European lobster Homarus gammarus. In a set of experiments, we manipulated the C:N:P stoichiometry of the primary producers, and accordingly those of the primary consumer. In a first experiment, R. salina was grown under N- and P-limitation and the nutrient content of the algae was manipulated by addition of the limiting nutrient to create a food quality gradient. In a second experiment, the effect on lobster larvae of long- and short-term exposure to food of varying quality during ontogenetic development was investigated. The condition of the lobster larvae was negatively affected even by subtle N- and P-nutrient limitations of the algae. Furthermore, younger lobster larvae were more vulnerable to nutrient limitation than older ones, suggesting an ontogenetic shift in the capacity of lobster larvae to cope with low quality food. The results presented here might have substantial consequences for the survival of lobster larvae in the field, as, in the light of future climate change and re-oligotrophication of the North Sea, lobster larvae might face marked changes in temperature and nutrient conditions, thus significantly altering their condition and growth.

  6. 1H NMR metabolic profiling of cod (Gadus morhua) larvae: potential effects of temperature and diet composition during early developmental stages.

    PubMed

    Chauton, Matilde Skogen; Galloway, Trina Falck; Kjørsvik, Elin; Størseth, Trond Røvik; Puvanendran, Velmurugu; van der Meeren, Terje; Karlsen, Ørjan; Rønnestad, Ivar; Hamre, Kristin

    2015-01-01

    Marine aquaculture offers a great source of protein for the increasing human population, and farming of, for example, Atlantic salmon is a global industry. Atlantic cod farming however, is an example of a promising industry where the potential is not yet realized. Research has revealed that a major bottleneck to successful farming of cod is poor quality of the larvae and juveniles. A large research program was designed to increase our understanding of how environmental factors such as temperature and nutrition affects cod larvae development. Data on larvae growth and development were used together with nuclear magnetic resonance. The NMR data indicated that the temperature influenced the metabolome of the larvae; differences were related to osmolytes such as betaine/TMAO, the amino acid taurine, and creatine and lactate which reflect muscle activity. The larvae were fed Artemia from stage 2, and this was probably reflected in a high taurine content of older larvae. Larvae fed with copepods in the nutrition experiment also displayed a high taurine content, together with higher creatine and betaine/TMAO content. Data on the cod larvae metabolome should be coupled to data on gene expression, in order to identify events which are regulated on the genetic level versus regulation resulting from temperature or nutrition during development, to fully understand how the environment affects larval development. PMID:26545964

  7. 1H NMR metabolic profiling of cod (Gadus morhua) larvae: potential effects of temperature and diet composition during early developmental stages

    PubMed Central

    Chauton, Matilde Skogen; Galloway, Trina Falck; Kjørsvik, Elin; Størseth, Trond Røvik; Puvanendran, Velmurugu; van der Meeren, Terje; Karlsen, Ørjan; Rønnestad, Ivar; Hamre, Kristin

    2015-01-01

    ABSTRACT Marine aquaculture offers a great source of protein for the increasing human population, and farming of, for example, Atlantic salmon is a global industry. Atlantic cod farming however, is an example of a promising industry where the potential is not yet realized. Research has revealed that a major bottleneck to successful farming of cod is poor quality of the larvae and juveniles. A large research program was designed to increase our understanding of how environmental factors such as temperature and nutrition affects cod larvae development. Data on larvae growth and development were used together with nuclear magnetic resonance. The NMR data indicated that the temperature influenced the metabolome of the larvae; differences were related to osmolytes such as betaine/TMAO, the amino acid taurine, and creatine and lactate which reflect muscle activity. The larvae were fed Artemia from stage 2, and this was probably reflected in a high taurine content of older larvae. Larvae fed with copepods in the nutrition experiment also displayed a high taurine content, together with higher creatine and betaine/TMAO content. Data on the cod larvae metabolome should be coupled to data on gene expression, in order to identify events which are regulated on the genetic level versus regulation resulting from temperature or nutrition during development, to fully understand how the environment affects larval development. PMID:26545964

  8. Potential utilization of Artemia franciscana eggs as food for Coleomegilla maculata

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We tested the hypothesis that Artemia franciscana Kellogg (brine shrimp, Anostraca: Artemiidae) eggs are suitable factitious, i.e., alternative, food to support the life history of a predatory ladybird beetle, Coleomegilla maculata DeGeer (Coleoptera: Coccinellidae). Using progeny from a stock colo...

  9. Bioconversion of omega-six to omega-three polyunsaturated fatty acids in Artemia

    SciTech Connect

    Omara-Alwala, T.R.

    1986-01-01

    A study was conducted to provide conclusive evidence for the bioconversion of 18:2W6 to 20:5W3 in Artemia and to establish a possible biosynthetic pathway responsible for the bioconversion. Except for fatty acid profile, the diet was considered complete in its nutritional quality. It was deficient in 20:5W3, an essential fatty acid for marine fish, but adequate in 18:3W3, an essential fatty acid for freshwater fish. The Artemia raised on the diet showed a high level of 20:5W3 with little accumulation of 18:3W3, making them the marine type. There were no mortalities throughout the 7-day feeding period. Two-day-old Artemia were fed for 7 days on either control diet or treatment diet with (1-/sup 14/C) 18:2W6, along with various unlabeled fatty acids. Data confirmed that Artemia were able to bioconvert 18:2W6 to 20:5W3. The following biosynthetic sequence was proposed for the bioconversion: 18:2W6 - 18:3W3 - 20:3W3 - 20:4W3 - 20:5W3. All possible multistep pathways for the synthesis of 20:5W3 from 18:2W6 were worked out for any feeding experiments using dietary 18:2W6.

  10. Preparation of transgenic Dunaliella salina for immunization against white spot syndrome virus in crayfish.

    PubMed

    Feng, Shuying; Feng, Wenpo; Zhao, Ling; Gu, Huihui; Li, Qinghua; Shi, Ke; Guo, Sanxing; Zhang, Nannan

    2014-03-01

    Although a white spot syndrome virus (WSSV) subunit vaccine could significantly enhance the immune response and benefit the shrimp host, its practical application is currently not feasible because of drawbacks in existing expression systems. We generated a transgenic Dunaliella salina (D. salina) strain by introducing the WSSV VP28 gene to produce a novel oral WSSV subunit vaccine. Following transformation of D. salina, VP28 gene expression was assessed by reverse transcription polymerase chain reaction (RT-PCR) assays, enzyme-linked immunosorbent assays (ELISAs), and western blot analysis. The RT-PCR results indicated that the VP28 gene was successfully expressed in D. salina cells. The presence of recombinant VP28 proteins with natural bioactivity was confirmed by western blot analysis and ELISA. Animal vaccination experiments indicated that transgenic D. salina can induce protection against WSSV by oral delivery in crayfish. Our findings indicate that the VP28 gene can be successfully expressed in transgenic D. salina and can be applied as an oral vaccine to protect crayfish against WSSV. We have demonstrated that it is feasible to produce an oral vaccine using D. salina, and thereby provide a new method for controlling other viral diseases in crustaceans.

  11. Salinas - An implicit finite element structural dynamics code developed for massively parallel platforms

    SciTech Connect

    BHARDWAJ, MANLJ K.; REESE,GARTH M.; DRIESSEN,BRIAN; ALVIN,KENNETH F.; DAY,DAVID M.

    2000-04-06

    As computational needs for structural finite element analysis increase, a robust implicit structural dynamics code is needed which can handle millions of degrees of freedom in the model and produce results with quick turn around time. A parallel code is needed to avoid limitations of serial platforms. Salinas is an implicit structural dynamics code specifically designed for massively parallel platforms. It computes the structural response of very large complex structures and provides solutions faster than any existing serial machine. This paper gives a current status of Salinas and uses demonstration problems to show Salinas' performance.

  12. Cultivation of Nannochloropsis salina in municipal wastewater or digester centrate.

    PubMed

    Dong, Bingfeng; Ho, Nam; Ogden, Kimberly L; Arnold, Robert G

    2014-05-01

    Meaningful use of biofuels for transportation depends on utilization of water from non-traditional, non-potable resources. Here it is hypothesized that (i) reclaimed wastewater or nutrient-rich side streams derived from municipal wastewater treatment are suitable for that purpose and (ii) use of those waters for algal growth can promote water quality through nutrient management. Experiments showed that metals levels in municipal wastewaters are unlikely to inhibit algal growth and lipid production, at least by metals tolerant microalgae like Nannochloropsis salina. Cells grew without inhibition in treated municipal wastewater or centrate derived from wastewater treatment at additions up to 75 percent v/v in their normal growth medium minus nitrogen and phosphorus. Although wastewater provides a suitable nutrient source for algal growth, not enough municipal wastewater is available to support a meaningful biofuels industry without efficient water recycling and nutrient recovery/reuse from spent algae. PMID:24565931

  13. Continuous flocculation-sedimentation for harvesting Nannochloropsis salina biomass.

    PubMed

    Chatsungnoen, Tawan; Chisti, Yusuf

    2016-03-20

    A continuous flow process is developed for recovery of the biomass of the marine microalga Nannochloropsis salina. Flocculation-sedimentation is used to recover the biomass from an algal suspension with an initial dry biomass concentration of 0.5 g L(-1), as would be typical of a raceway-based biomass production system. More than 85% of the biomass initially in suspension could be settled by gravity in a flocculation-sedimentation device with a total residence time of ∼148 min. Aluminum sulfate was used as an inexpensive, readily available and safe flocculant. The optimal flocculant dosage (as Al2(SO4)3) was 229 mg L(-1). Relative to a highly effective 62-min batch flocculation-sedimentation process for the same alga and flocculant, the continuous flow operation took longer and required nearly double the flocculant dose. The design of the flocculation-sedimentation system is explained. PMID:26880538

  14. Phase toxicity of dodecane on the microalga Dunaliella salina.

    PubMed

    Kleinegris, Dorinde M M; van Es, Marjon A; Janssen, Marcel; Brandenburg, Willem A; Wijffels, René H

    2011-12-01

    In the so-called milking process of Dunaliella salina carotenoids are extracted and simultaneously produced by the culture, whilst the biomass concentration remains constant. Different theories exist about the extraction mechanisms although none have been proven yet. In this research, direct contact between dodecane and cells during the extraction process was studied microscopically and effects of direct contact were determined during in situ extraction experiments. Our results showed that water-solvent interphase contact resulted in cell death. This cell death and consequent cell rupture resulted in the release and concomitant extraction of the carotenoids. Furthermore, it has been suggested to add a small amount of dichloromethane to the biocompatible dodecane to create an organic phase with more extraction capacity. Our results showed that the addition of dichloromethane resulted in increased cell death and consequently the extraction rate increased. The improved solubility of carotenoids in an organic phase with dichloromethane did not significantly increase the extraction rate.

  15. A biometric and ecologic comparison between Artemia from Mexico and Chile

    PubMed Central

    Castro, Thalía B; Gajardo, Gonzalo; Castro, Jorge M; Castro, Germán M

    2006-01-01

    Background A preliminary biometric and ecologic database for the brine shrimp Artemia from Mexico and Chile is presented. The area abounds in small and seasonal ponds and large inland lakes, the latter mainly located in Mexico, although relatively large and isolated lakes are found in complex hydrological settings in pre-high plateau areas of Chile. This paper summarizes research efforts aimed at the localization, characterization, and evaluation of the aquaculture potential of Artemia populations in Mexico and Chile, which exhibit great habitat diversity (ponds, salterns, coastal lagoons, sea arms, coastal and inland lakes), contrasting weather conditions and different levels of isolation and human intervention. Results This study covered locations between 29° north latitude (Baja California, Mexico) to 50° south latitude (Puerto Natales, Chile). Biological characteristics considered are species name, reproductive mode, cyst diameter, chorion thickness, and nauplius length, whereas ecological data include pond size, pH, salinity, temperature, and water ionic composition. Artemia franciscana is the only species found in Mexico, it exists together with A. persimilis in Chile, though separated geographically. Ecological differences in habitat exist between both regions but also within countries, a pattern particularly clear with regard to water composition. Surprisingly, a Mexican (Cuatro Ciénegas, A. franciscana) and a Chilean location (Torres del Paine, A. persimilis) share habitat characteristics, at least for the period when data were collected. The discriminat analysis for cyst diameter and nauplius length shows that Artemia from only one location match in cyst diameter with those from San Francisco Bay (SFB) (Point Lobos), and one (Marquez) is far apart from SFB and all the others. The Chilean locations (Pampilla, Cejar, Cahuil, Llamara, Yape) share cyst diameter, but tend to differ from SFB. The remaining Mexican locations (Juchitan, Ohuira, Yavaros) are

  16. Internal communications program expands at Salina Regional Health Center as the health system grows.

    PubMed

    Herreria, J

    1999-01-01

    The e-mail system is evolving into one of Salina, Kan., Regional Health Center's primary sources of communications for its 1,350 employees and physicians. Check out how the health system uses other internal communication tools. PMID:10387297

  17. Determination of extremely high pressure tolerance of brine shrimp larvae by using a new pressure chamber system.

    PubMed

    Seo, Mihye; Koyama, Sumihiro; Toyofuku, Takashi; Kojima, Shigeaki; Watanabe, Hiromi

    2013-11-01

    Hydrostatic pressure is the only one of a range of environmental parameters (water temperature, salinity, light availability, and so on) that increases in proportion with depth. Pressure tolerance is therefore essential to understand the foundation of populations and current diversity of faunal compositions at various depths. In the present study, we used a newly developed pressure chamber system to examine changes in larval activity of the salt-lake crustacean, Artemia franciscana, in response to a range of hydrostatic pressures. We showed that A. franciscana larvae were able to survive for a short period at pressures of ≤ 60 MPa (approximately equal to the pressure of 6000 m deep). At a pressure of > 20 MPa, larval motor ability was suppressed, but not lost. Meanwhile, at a pressure of > 40 MPa, some of the larval motor ability was lost without recovery after decompression. For all experiments, discordance of movement and timing between right and left appendages, was observed at pressures of > 20 MPa. Our results indicate that the limit of pressure for sustaining active behavior of A. franciscana larvae is ∼20 MPa, whereas the limit of pressure for survival is within the range 30-60 MPa. Thus, members of the genus Artemia possess the ability to resist a higher range of pressures than their natural habitat depth. Our findings demonstrated an example of an organism capable of invading deeper environment in terms of physical pressure tolerance, and indicate the need and importance of pressure study as an experimental method. PMID:24224473

  18. The Dunaliella salina organelle genomes: large sequences, inflated with intronic and intergenic DNA

    SciTech Connect

    Smith, David R.; Lee, Robert W.; Cushman, John C.; Magnuson, Jon K.; Tran, Duc; Polle, Juergen E.

    2010-05-07

    Abstract Background: Dunaliella salina Teodoresco, a unicellular, halophilic green alga belonging to the Chlorophyceae, is among the most industrially important microalgae. This is because D. salina can produce massive amounts of β-carotene, which can be collected for commercial purposes, and because of its potential as a feedstock for biofuels production. Although the biochemistry and physiology of D. salina have been studied in great detail, virtually nothing is known about the genomes it carries, especially those within its mitochondrion and plastid. This study presents the complete mitochondrial and plastid genome sequences of D. salina and compares them with those of the model green algae Chlamydomonas reinhardtii and Volvox carteri. Results: The D. salina organelle genomes are large, circular-mapping molecules with ~60% noncoding DNA, placing them among the most inflated organelle DNAs sampled from the Chlorophyta. In fact, the D. salina plastid genome, at 269 kb, is the largest complete plastid DNA (ptDNA) sequence currently deposited in GenBank, and both the mitochondrial and plastid genomes have unprecedentedly high intron densities for organelle DNA: ~1.5 and ~0.4 introns per gene, respectively. Moreover, what appear to be the relics of genes, introns, and intronic open reading frames are found scattered throughout the intergenic ptDNA regions -- a trait without parallel in other characterized organelle genomes and one that gives insight into the mechanisms and modes of expansion of the D. salina ptDNA. Conclusions: These findings confirm the notion that chlamydomonadalean algae have some of the most extreme organelle genomes of all eukaryotes. They also suggest that the events giving rise to the expanded ptDNA architecture of D. salina and other Chlamydomonadales may have occurred early in the evolution of this lineage. Although interesting from a genome evolution standpoint, the D. salina organelle DNA sequences will aid in the development of a viable

  19. Hemato-immunological responses of Heros severus fed diets supplemented with different levels of Dunaliella salina.

    PubMed

    Alishahi, M; Karamifar, M; Mesbah, M; Zarei, M

    2014-02-01

    In this study, the effects of oral administration of different levels of Dunaliella salina (a natural β-carotene source) on growth parameters, immunological and hematological indices, as well as skin carotenoids, of Heros severus were investigated. One hundred and eighty H. severus weighing 27 ± 0.5 g were divided randomly into four groups in triplicate (15 fish in each replicate). Groups 1-4 received food supplemented with 0, 50, 100 and 200 mg kg⁻¹ D. salina powder, respectively. After 6 weeks, the growth parameters were compared among the groups. Blood samples were taken from each group, and hematological parameters including red blood cell count (RBC), white blood cell count (WBC), hematocrit (PCV), hemoglobin (Hb) and immunological indices (serum and mucus lysozyme and bactericidal activity, resistance against Aeromonas hydrophila infection) as well as carotenoid content of skin were evaluated. Results showed that some growth indices increased significantly in fish fed with 100 and 200 mg kg⁻¹ D. salina-supplemented food (P < 0.05). Although serum lysozyme activity was increased in fish fed with food supplemented with 100 and 200 mg kg⁻¹ D. salina (P < 0.05), no significant change was observed in serum and mucus bactericidal activity and mucus lysozyme activity among the groups (P > 0.05). Most of the hematological parameters such as WBC, RBC, PCV and Hb significantly increased in D. salina-treated fish compared with controls (P < 0.05). Mortality induced after challenge with A. hydrophila in 200 mg kg⁻¹ D. salina-treated fish was 36.67 %, which significantly decreased compared with control (P < 0.05). Skin carotenoid content in all D. salina treatments was statistically higher than that of control (P < 0.05). Conclusively, D. salina as a food additive can affect positively the growth, immunological and hematological parameters of H. severus.

  20. A symbiotic bacterium differentially influences arsenate absorption and transformation in Dunaliella salina under different phosphate regimes.

    PubMed

    Wang, Ya; Zhang, Chun Hua; Lin, Man Man; Ge, Ying

    2016-11-15

    In this study, we investigated the effects of a symbiotic bacterium and phosphate (PO4(3-)) nutrition on the toxicity and metabolism of arsenate (As(V)) in Dunaliella salina. The bacterium was identified as Alteromonas macleodii based on analysis of its 16S rRNA gene sequence. When no As(V) was added, A. macleodii significantly enhanced the growth of D. salina, irrespective of PO4(3-) nutrition levels, but this effect was reversed after As(V)+PO4(3-) treatment (1.12mgL(-1)) for 3 days. Arsenic (As) absorption by the non-axenic D. salina was significantly higher than that by its axenic counterpart during incubation with 1.12mgL(-1) PO4(3-). However, when the culture was treated with 0.112mgL(-1) PO4(3-), As(V) reduction and its subsequent arsenite (As(III)) excretion by non-axenic D. salina were remarkably enhanced, which, in turn, contributed to lower As absorption in non-axenic algal cells from days 7 to 9. Moreover, dimethylarsinic acid was synthesized by D. salina alone, and the rates of its production and excretion were accelerated when the PO4(3-) concentration was 0.112mgL(-1). Our data demonstrate that A. macleodii strongly affected As toxicity, uptake, and speciation in D. salina, and these impacts were mediated by PO4(3-) in the cultures.

  1. [Characterization of the functional domain of STT3a of oligosaccharyltransferase from Dunaliella salina].

    PubMed

    Wang, Cui; Li, Jie; Liu, Liping; Zeng, Lei; Xue, Lexun

    2010-06-01

    To investigate the function of STT3a gene in salt adaptation and flagellar regeneration of Dunaliella salina (D. salina), a pair of degenerate primers was designed according to conserved homologous amino acid sequences of VCVFTA and DVDYVL of STT3a from Chlamydomonas, Arabidopsis thaliana and other organisms. A cDNA sequence of 1 650 bp encoding a whole functional domain of STT3a was amplified from D. salina by RT-PCR and 3' Rapid Amplification of cDNA Ends (RACE), which shared homology with Chlamydomonas (48%), Arabidopsis thaliana (50%), Homo sapiens (46%), etc. Real-time fluorescence quantitative PCR (real-time Q-PCR) demonstrated that the STT3a mRNAs from D. salina were induced by increased concentration of NaCl, and increased to 11-fold higher by 3.5 mol/L NaCl than that by 1.5 mol/L NaCl (P < 0.01). Also, STT3a mRNA of D. salina maintained at a higher level in the process of flagellar regeneration with than without experiencing deflagellar treatment. In conclusion, the findings of this study demonstrate that the high expression of the STT3a gene enhances the capability of salt adaptation and flagellar regeneration in D. salina.

  2. S-adenosyl homocysteine hydrolase (SAHH) accelerates flagellar regeneration in Dunaliella salina.

    PubMed

    Li, Qinghua; Zhu, Liqiang; Yan, Yunmeng; Chai, Dandan; Li, Jie; Xue, Lexun

    2013-08-01

    S-adenosylhomocysteine hydrolase (SAHH) is an enzyme, which catalyzes the hydrolysis of S-adenosylhomocysteine (SAH) which is formed after the donation of the methyl group of S-adenosylmethionine (SAM) to a methyl acceptor in methylation reaction. As a potent regulator of methylation, SAHH plays a critical role in methylation reaction in the cells. Here we cloned the SAHH gene from unicellular green alga Dunaliella salina (dsSAHH) and investigated its effects on flagellar regeneration of D. salina, and found that dsSAHH was upregulated both at the protein and the transcription levels during pH shock-triggered flagellar regeneration of D. salina. The flagellar regeneration was accelerated when dsSAHH was overexpressed, but it was inhibited by SAHH inhibitor 3-deazaadenosine (DZA). Moreover, a receptor for activated C kinase 1 from D. salina (dsRACK1), which was identified to interact with dsSAHH, was increased when dsSAHH was overexpressed in D. salina as shown by real-time PCR. The findings of this study suggest that dsSAHH may participate in the regulation of flagellar regeneration of D. salina.

  3. Interspecific competition and allelopathic interaction between Karenia mikimotoi and Dunaliella salina in laboratory culture

    NASA Astrophysics Data System (ADS)

    He, Dong; Liu, Jiao; Hao, Qiang; Ran, Lihua; Zhou, Bin; Tang, Xuexi

    2016-03-01

    Algal allelopathy is a manifold ecological/physiological phenomenon that is focused on chemical interactions and autotoxicity. We investigated the allelopathic interactions between Karenia mikimotoi and Dunaliella salina in laboratory cultures based on diff erent temperature (15°C, 20°C, and 25°C) and lighting (40, 80, and 160 μmol/(m2·s)) conditions. The growth of D. salina in bi-algae culture (1:1 size/density) was significantly restrained. The results of cell-free filtrate culture indicate that direct cell-tocell contact was not necessary in interspecific competition. Further experimental results demonstrated that allelochemicals released from K. mikimotoi were markedly influenced by both temperature ( P =0.013) and irradiance ( P =0.003), resulting in diff erent growth characteristics of D. salina in filtrate mediums. Compared with the plateau period, K. mikimotoi exudates in the exponential phase had a stronger short-term inhibition effect on D. salina in normal conditions. A clear concentration-dependent relationship was observed in the effect of allelochemicals released from K. mikimotoi with low-promoting and high-repressing effects on D. Salina in a short time-scale. In addition, allelopathic substances remain stable and effective under high temperature and pressure stress. Many flocculent sediments adhering with D. salina cells were observed in all filtrate mediums, while the quantity and color depended on the original culture conditions.

  4. Participation of metanauplii and juvenile individuals of Artemia parthenogenetica (Branchiopoda) in the circulation of avian cestodes.

    PubMed

    Redón, Stella; Amat, Francisco; Hontoria, Francisco; Vasileva, Gergana P; Nikolov, Pavel N; Georgiev, Boyko B

    2011-04-01

    Adult crustaceans of the genus Artemia (brine shrimps) are intermediate hosts in the life cycle of cestode species parasitic in aquatic birds as their definitive hosts. However, there are no data on the role of larval and juvenile brine shrimps in the transmission of avian helminth parasites. In order to examine the possible role of early developmental stages (nauplii, metanauplii and juveniles) of Artemia for the circulation of avian cestodes, the natural cestode infection in the population of Artemia parthenogenetica from La Mata Lagoon, Mediterranean coast of Spain, was studied. Metacestodes (cysticercoids) of four cestode species were recorded in adult brine shrimps: Flamingolepis liguloides and Flamingolepis flamingo (hymenolepidids parasitic in flamingos), Confluaria podicipina (a hymenolepidid species parasitic in grebes) and Eurycestus avoceti (a dilepidid species parasitic in avocets, stilts, plovers and, to a lesser extent, in flamingos). No cysticercoids were found in nauplii. Two species, F. liguloides and F. flamingo, were found in metanauplii and juvenile brine shrimps. Only 36.3% of the cysticercoids of F. liguloides occurred in adult brine shrimps; the remaining 63.7% were parasitic in metanauplii (39.6%) and juveniles (24.1%). Similarly, the metacestodes of F. flamingo were also distributed among various age groups: in adults (44.4% of cysticercoids), juveniles (27.8%) and metanauplii (27.8%). These results indicate that the early developmental stages of Artemia have an important role for the circulation of certain parasite species. No cysticercoids of C. podicipina and E. avoceti were recorded in larval and juvenile brine shrimps. The selective infestation of larval brine shrimps with flamingo parasites is probably associated with the feeding behaviour of definitive hosts, which are filtering predators; in contrast, grebes and waders pick brine shrimps individually one by one. The possible underlying mechanism for selective infestation of

  5. The structure of Artemia sp. (brine shrimp) haemoglobins. Purification of a structural unit to homogeneity.

    PubMed

    Moens, L; Van Hauwaert, M L; Wolf, G

    1985-05-01

    The extracellular haemoglobins (Mr 260 000) of the brine shrimp Artemia sp. were cleaved by limited digestion with subtilisin. Structural units of Mr 16 000, which can bind dioxygen reversibly, were isolated. Analysis of the 16 000-Mr fraction (E) reveals the presence of a limited number of structural units. A single type of structural unit, E1 (Mr 15 800; pI4.8), was purified to homogeneity and characterized. PMID:4004806

  6. Participation of metanauplii and juvenile individuals of Artemia parthenogenetica (Branchiopoda) in the circulation of avian cestodes.

    PubMed

    Redón, Stella; Amat, Francisco; Hontoria, Francisco; Vasileva, Gergana P; Nikolov, Pavel N; Georgiev, Boyko B

    2011-04-01

    Adult crustaceans of the genus Artemia (brine shrimps) are intermediate hosts in the life cycle of cestode species parasitic in aquatic birds as their definitive hosts. However, there are no data on the role of larval and juvenile brine shrimps in the transmission of avian helminth parasites. In order to examine the possible role of early developmental stages (nauplii, metanauplii and juveniles) of Artemia for the circulation of avian cestodes, the natural cestode infection in the population of Artemia parthenogenetica from La Mata Lagoon, Mediterranean coast of Spain, was studied. Metacestodes (cysticercoids) of four cestode species were recorded in adult brine shrimps: Flamingolepis liguloides and Flamingolepis flamingo (hymenolepidids parasitic in flamingos), Confluaria podicipina (a hymenolepidid species parasitic in grebes) and Eurycestus avoceti (a dilepidid species parasitic in avocets, stilts, plovers and, to a lesser extent, in flamingos). No cysticercoids were found in nauplii. Two species, F. liguloides and F. flamingo, were found in metanauplii and juvenile brine shrimps. Only 36.3% of the cysticercoids of F. liguloides occurred in adult brine shrimps; the remaining 63.7% were parasitic in metanauplii (39.6%) and juveniles (24.1%). Similarly, the metacestodes of F. flamingo were also distributed among various age groups: in adults (44.4% of cysticercoids), juveniles (27.8%) and metanauplii (27.8%). These results indicate that the early developmental stages of Artemia have an important role for the circulation of certain parasite species. No cysticercoids of C. podicipina and E. avoceti were recorded in larval and juvenile brine shrimps. The selective infestation of larval brine shrimps with flamingo parasites is probably associated with the feeding behaviour of definitive hosts, which are filtering predators; in contrast, grebes and waders pick brine shrimps individually one by one. The possible underlying mechanism for selective infestation of

  7. The transcription factor p8 regulates autophagy during diapause embryo formation in Artemia parthenogenetica.

    PubMed

    Lin, Cheng; Jia, Sheng-Nan; Yang, Fan; Jia, Wen-Huan; Yu, Xiao-Jian; Yang, Jin-Shu; Yang, Wei-Jun

    2016-07-01

    Autophagy is an essential homeostatic process by which cytoplasmic components, including macromolecules and organelles, are degraded by lysosome. Increasing evidence suggests that phosphorylated AMP-activated protein kinase (p-AMPK) and target of rapamycin (TOR) play key roles in the regulation of autophagy. However, the regulation of autophagy in quiescent cells remains unclear, despite the fact that autophagy is known to be critical for normal development, regeneration, and degenerative diseases. Here, crustacean Artemia parthenogenetica was used as a model system because they produced and released encysted embryos that enter a state of obligate dormancy in cell quiescence to withstand various environmental threats. We observed that autophagy was increased before diapause stage but dropped to extremely low level in diapause cysts in Artemia. Western blot analyses indicated that the regulation of autophagy was AMPK/TOR independent during diapause embryo formation. Importantly, the level of p8 (Ar-p8), a stress-inducible transcription cofactor, was elevated at the stage just before diapause and was absent in encysted embryos, indicating that Ar-p8 may regulate autophagy. The results of Ar-p8 knockdown revealed that Ar-p8 regulated autophagy during diapause formation in Artemia. Moreover, we observed that activating transcription factors 4 and 6 (ATF4 and ATF6) responded to Ar-p8-regulated autophagy, indicating that autophagy targeted endoplasmic reticulum (ER) during diapause formation in Artemia. Additionally, AMPK/TOR-independent autophagy was validated in human gastric cancer MKN45 cells overexpressing Ar-p8. The findings presented here may provide insights into the role of p8 in regulating autophagy in quiescent cells. PMID:27125785

  8. Essential oils of Nigella sativa protects Artemia from the pathogenic effect of Vibrio parahaemolyticus Dahv2.

    PubMed

    Manju, Sivalingam; Malaikozhundan, Balasubramanian; Withyachumnarnkul, Boonsirm; Vaseeharan, Baskaralingam

    2016-05-01

    The anti-Vibrio activity of essential oils (EOs) of nine medicinal plants was tested against 28 Vibrio spp. isolated from diseased Fenneropenaeus indicus. EO of Nigella sativa exhibited anti-Vibrio activity against all Vibrio spp. and greater inhibition was noted for the isolate V2 which was identified as Vibrio parahaemolyticus Dahv2. Further, EO of N. sativa effectively inhibited V. parahaemolyticus Dahv2 with an inhibition zone of 23.9mm at 101.2μgml(-1). Moreover, EO of N. sativa revealed anti-biofilm activity at 101.2μgml(-1) against V. parahaemolyticus Dahv2 and inhibited the growth of V. parahaemolyticus Dahv2 at 100μgml(-1).In vivo experimental infection studies showed that the survival of Artemia spp. infected with V. parahaemolyticus Dahv2 at 1×10(3)cfuml(-1) was only 40%. However, the survival of Artemia spp. was significantly increased after challenge with 100μgml(-1) of EO of N. sativa. EO of N. sativa showed higher anti-oxidant potential and total phenol content than other EOs tested. The anti-oxidant activity of EO of N. sativa was highly correlated to their total phenolic contents (r=0.836, P<0.05). This observation suggests that EO of N. sativa protected the Artemia spp. after experimental infection of V. parahaemolyticus Dahv2.

  9. The study of fkbp and ubiquitin reveals interesting aspects of Artemia stress history.

    PubMed

    Maniatsi, Stefania; Farmaki, Theodora; Abatzopoulos, Theodore J

    2015-08-01

    Research on stress responses in animals has increased greatly during the last decades. Though most studies focus on the cellular and molecular bases of the stress response mechanisms, the ecological and evolutionary aspects of stress responses gain more and more interest. Here, we use species and parthenogenetic strains of the genus Artemia, an extremophile model organism, to study, for the first time, a protein well known for its chaperone activity and its involvement in stress responses. More specifically, transcription and protein accumulation of an FK506-Binding Protein (FKBP) homologue were investigated under heat and salt stresses. Additionally, the mRNA levels of ubiquitin, a heat-inducible protein related to the proteasomal pathway, were quantitated under these conditions. Biochemical and phylogenetic analyses showed that the studied FKBP orthologue is a typical representative of the family that clusters with other crustacean sequences. The expression was increased in both fkbp and ubiquitin genes after salt and heat stresses. However, our results in combination with the fact that Artemia species and parthenogenetic strains, selected for this study, exhibit different heat or salt tolerance provide useful hints about the evolutionary significance of FKBP and ubiquitin. Regarding FKBP, mRNA expression and protein accumulation seem to depend on the environmental conditions and the evolutionary history of each Artemia population while ubiquitin has a clear and more conserved role under heat shock. PMID:25868628

  10. Essential oils of Nigella sativa protects Artemia from the pathogenic effect of Vibrio parahaemolyticus Dahv2.

    PubMed

    Manju, Sivalingam; Malaikozhundan, Balasubramanian; Withyachumnarnkul, Boonsirm; Vaseeharan, Baskaralingam

    2016-05-01

    The anti-Vibrio activity of essential oils (EOs) of nine medicinal plants was tested against 28 Vibrio spp. isolated from diseased Fenneropenaeus indicus. EO of Nigella sativa exhibited anti-Vibrio activity against all Vibrio spp. and greater inhibition was noted for the isolate V2 which was identified as Vibrio parahaemolyticus Dahv2. Further, EO of N. sativa effectively inhibited V. parahaemolyticus Dahv2 with an inhibition zone of 23.9mm at 101.2μgml(-1). Moreover, EO of N. sativa revealed anti-biofilm activity at 101.2μgml(-1) against V. parahaemolyticus Dahv2 and inhibited the growth of V. parahaemolyticus Dahv2 at 100μgml(-1).In vivo experimental infection studies showed that the survival of Artemia spp. infected with V. parahaemolyticus Dahv2 at 1×10(3)cfuml(-1) was only 40%. However, the survival of Artemia spp. was significantly increased after challenge with 100μgml(-1) of EO of N. sativa. EO of N. sativa showed higher anti-oxidant potential and total phenol content than other EOs tested. The anti-oxidant activity of EO of N. sativa was highly correlated to their total phenolic contents (r=0.836, P<0.05). This observation suggests that EO of N. sativa protected the Artemia spp. after experimental infection of V. parahaemolyticus Dahv2. PMID:26945773

  11. Laboratory generation of new parthenogenetic lineages supports contagious parthenogenesis in Artemia

    PubMed Central

    Amat, Francisco; Hontoria, Francisco; Gómez, Africa

    2014-01-01

    Contagious parthenogenesis—a process involving rare functional males produced by a parthenogenetic lineage which mate with coexisting sexual females resulting in fertile parthenogenetic offspring—is one of the most striking mechanisms responsible for the generation of new parthenogenetic lineages. Populations of the parthenogenetic diploid brine shrimp Artemia produce fully functional males in low proportions. The evolutionary role of these so-called Artemia rare males is, however, unknown. Here we investigate whether new parthenogenetic clones could be obtained in the laboratory by mating these rare males with sexual females. We assessed the survival and sex ratio of the hybrid ovoviviparous offspring from previous crosses between rare males and females from all Asiatic sexual species, carried out cross-mating experiments between F1 hybrid individuals to assess their fertility, and estimated the viability and the reproductive mode of the resulting F2 offspring. Molecular analysis confirmed the parentage of hybrid parthenogenetic F2. Our study documents the first laboratory synthesis of new parthenogenetic lineages in Artemia and supports a model for the contagious spread of parthenogenesis. Our results suggest recessive inheritance but further experiments are required to confirm the likelihood of the contagious parthenogenesis model. PMID:25024909

  12. Nitrate Contamination of Deep Aquifers in the Salinas Valley, California

    NASA Astrophysics Data System (ADS)

    Moran, J. E.; Esser, B. K.; Hillegonds, D. J.; Holtz, M.; Roberts, S. K.; Singleton, M. J.; Visser, A.; Kulongoski, J. T.; Belitz, K.

    2011-12-01

    The Salinas Valley, known as 'the salad bowl of the world', has been an agricultural center for more than 100 years. Irrigated row crops such as lettuce and strawberries dominate both land use and water use. Groundwater is the exclusive supply for both irrigation and drinking water. Some irrigation wells and most public water supply wells in the Salinas Valley are constructed to draw water from deep portions of the aquifer system, where contamination by nitrate is less likely than in the shallow portions of the aquifer system. However, a number of wells with top perforations greater than 75 m deep, screened below confining or semi-confining units, have nitrate concentrations greater than the Maximum Contaminant Limit (MCL) of 45 mg/L as NO3-. This study uses nitrate concentrations from several hundred irrigation, drinking water, and monitoring wells (Monterey County Water Resources Agency, 1997), along with tritium-helium groundwater ages acquired at Lawrence Livermore National Laboratory through the State of California Groundwater Monitoring and Assessment (GAMA) program (reported in Kulongoski et al., 2007 and in Moran et al., in press), to identify nitrate 'hot spots' in the deep aquifer and to examine possible modes of nitrate transport to the deep aquifer. In addition, observed apparent groundwater ages are compared with the results of transport simulations that use particle tracking and a stochastic-geostatistical framework to incorporate aquifer heterogeneity to determine the distribution of travel times from the water table to each well (Fogg et al., 1999). The combined evidence from nitrate, tritium, tritiogenic 3He, and radiogenic 4He concentrations, reveals complex recharge and flow to the capture zone of the deep drinking water wells. Widespread groundwater pumping for irrigation accelerates vertical groundwater flow such that high nitrate groundwater reaches some deep drinking water wells. Deeper portions of the wells often draw in water that recharged

  13. Spatial and temporal variability of water quality and zooplankton in an artisanal salina

    NASA Astrophysics Data System (ADS)

    Vieira, Natividade; Bio, Ana

    2011-02-01

    Conditions in artisanal salterns, or salinas, vary depending on their physical structure, seasonal effects, and the two periods of the salt production cycle. They therefore constitute unique wetland habitats, with particular communities that are still poorly studied. Water quality and zooplankton of a working artisanal salina were studied to evaluate spatial variability between sections and temporal variability between the salt production and flooded periods and between seasons. Zooplankton communities were related to environmental conditions. Sampling took place every second week, during almost two years, at six sites of the Tanoerias salina in Aveiro, Portugal: at the beginning and centre of the salina inlet channel, in a supply pond, in two evaporator and one crystalliser ponds. Since salt production occurs in the warm season only, seasonal effects concur with those caused by the salt production cycle. Results showed significant differences in temperature, dissolved oxygen (DO) and biochemical oxygen demand (BOD 5) between salt production and flooded periods, i.e. summer and spring/winter seasons. Salinity and alkalinity were linked to salt production with extreme values in the salt-producing crystalliser pond. Zooplankton communities varied between seasons, but also with the salina section and the salt production cycle. Zooplankton densities and diversity tended to be lower during salt production, particularly under the extreme living conditions in the salina crystalliser pond. Variation in zooplankton communities between samples was mainly influenced by temperature, i.e. season, at the salina inlet, by BOD 5 or DO, also related to temperature and season, in the first ponds and by nutrients throughout the system.

  14. Cytological, molecular and life cycle characterization of Anostracospora rigaudi n. g., n. sp. and Enterocytospora artemiae n. g., n. sp., two new microsporidian parasites infecting gut tissues of the brine shrimp Artemia.

    PubMed

    Rode, Nicolas Olivier; Landes, Julie; Lievens, Eva J P; Flaven, Elodie; Segard, Adeline; Jabbour-Zahab, Roula; Michalakis, Yannis; Agnew, Philip; Vivarès, Christian P; Lenormand, Thomas

    2013-08-01

    Two new microsporidia, Anostracospora rigaudi n. g., n. sp., and Enterocytospora artemiae n. g., n. sp. infecting the intestinal epithelium of Artemia parthenogenetica Bowen and Sterling, 1978 and Artemia franciscana Kellogg, 1906 in southern France are described. Molecular analyses revealed the two species belong to a clade of microsporidian parasites that preferentially infect the intestinal epithelium of insect and crustacean hosts. These parasites are morphologically distinguishable from other gut microsporidia infecting Artemia. All life cycle stages have isolated nuclei. Fixed spores measure 1·3×0·7 μm with 5-6 polar tube coils for A. rigaudi and 1·2×0·9 μm with 4 polar tube coils for E. artemiae. Transmission of both species is horizontal, most likely through the ingestion of spores released with the faeces of infected hosts. The minute size of these species, together with their intestinal localization, makes their detection and identification difficult. We developed two species-specific molecular markers allowing each type of infection to be detected within 3-6 days post-inoculation. Using these markers, we show that the prevalence of these microsporidia ranges from 20% to 75% in natural populations. Hence, this study illustrates the usefulness of molecular approaches to study prevalent, but cryptic, infections involving microsporidian parasites of gut tissues. PMID:23731593

  15. Characterization of vitamin B12 in Dunaliella salina.

    PubMed

    Kumudha, Anantharajappa; Sarada, Ravi

    2016-01-01

    Vitamin B12 is one of nature's complex metabolite which is industrially produced using certain bacteria. Algae could be an alternative source of vitamin B12 and in this study, vitamin B12 from a halotolerant green alga, Dunaliella salina V-101 was purified and characterized. The extract of Dunaliella was purified by passing through Amberlite XAD-2 and EASI-extract vitamin B12 immunoaffinity column. The total vitamin B12 content in purified sample fractions was 42 ± 2 μg/100 g dry weight as determined by the chemiluminescence method which was almost close to 49 ± 2 μg/100 g dry weight as estimated by microbiological method. Further quantification of total vitamin B12 using gold nanoparticle (AUNPs) based aptamer showed 40 ± 0.8/100 g dry weight. There was a good correlation among all the methods of quantification. Adenosylcobalamin, a form of vitamin B12 which is a cofactor for methylmalonyl CoA mutase was identified by HPLC. Upon quantification, Dunaliella was found to contain 34 ± 4 μg of adenosylcobalamin for 100 g dry biomass. Authenticity of adenosylcobalmin was confirmed by tandem mass spectrometry (MS/MS), selected ion recording (SIR) and multiple reaction monitoring (MRM) studies. PMID:26788012

  16. Characterization of vitamin B12 in Dunaliella salina.

    PubMed

    Kumudha, Anantharajappa; Sarada, Ravi

    2016-01-01

    Vitamin B12 is one of nature's complex metabolite which is industrially produced using certain bacteria. Algae could be an alternative source of vitamin B12 and in this study, vitamin B12 from a halotolerant green alga, Dunaliella salina V-101 was purified and characterized. The extract of Dunaliella was purified by passing through Amberlite XAD-2 and EASI-extract vitamin B12 immunoaffinity column. The total vitamin B12 content in purified sample fractions was 42 ± 2 μg/100 g dry weight as determined by the chemiluminescence method which was almost close to 49 ± 2 μg/100 g dry weight as estimated by microbiological method. Further quantification of total vitamin B12 using gold nanoparticle (AUNPs) based aptamer showed 40 ± 0.8/100 g dry weight. There was a good correlation among all the methods of quantification. Adenosylcobalamin, a form of vitamin B12 which is a cofactor for methylmalonyl CoA mutase was identified by HPLC. Upon quantification, Dunaliella was found to contain 34 ± 4 μg of adenosylcobalamin for 100 g dry biomass. Authenticity of adenosylcobalmin was confirmed by tandem mass spectrometry (MS/MS), selected ion recording (SIR) and multiple reaction monitoring (MRM) studies.

  17. Effect of Aloe barbadensis Miller juice on oxidative stress biomarkers in aerobic cells using Artemia franciscana as a model.

    PubMed

    Sirdaarta, J; Cock, I E

    2010-03-01

    This study reports on the induction of oxidative stress in aerobic cell systems by Aloe barbadensis Miller (Aloe vera) juice using the salt water crustacean Artemia franciscana as a model. A consistent pattern was observed in which Artemia franciscana nauplii responded to Aloe vera juice exposure with a decrease in the overall activity of redox related enzymes. Exposure of Artemia franciscana to sub-lethal levels of Aloe vera juice resulted in a decreased activity of thioredoxin reductase, glutathione reductase and glutathione peroxidase by 34% (66% enzymatic activity), 79% (21% enzymatic activity) and 90% (10% enzymatic activity), respectively. Similarly apparent was the trend whereby the co-exposure of the nauplii to vitamin E counteracted this effect. For each of the biomarker enzymes tested, vitamin E co-exposure resulted in enzyme activities closer to the control value (78%, 56% and 32% of control enzymatic activities for thioredoxin reductase, glutathione reductase and glutathione peroxidase activity, respectively). These results indicate that exposure to sub-lethal doses of Aloe vera juice induces alterations in the cellular redox status of Artemia franciscana and that the addition of vitamin E helps the Artemia franciscana nauplii to overcome/block the juice induced oxidative stress.

  18. Mosquitoes feeding on insect larvae.

    PubMed

    Harris, P; Riordan, D F; Cooke, D

    1969-04-11

    Caged Aedes aegypti and Culex tarsalis are attracted to insect larvae, engorge on their body fluids, and produce viable eggs. Attractiveness of the larvae is related to their size, shape, and color but not to their movement. The possibility that wild mosquitoes substitute insect hemolymph for vertebrate blood is discussed. PMID:5774191

  19. Cytotoxic effect of extract from Dunaliella salina against SH-SY5Y neuroblastoma cells.

    PubMed

    Atasever-Arslan, Belkis; Yilancioglu, Kaan; Bekaroglu, Maide G; Taskin, Emre; Altinoz, Eyup; Cetiner, Selim

    2015-04-01

    Cytotoxic effects of essential oils extracted from Dunaliella salina on SH-SY5Y human neuroblastoma cells were investigated in this study. GC-MS analysis was used for determination of the composition of essential oils found in Dunaliella salina extract. All experimented concentrations of Dunaliella salina extract on SH-SY5Y human neuroblastoma cells were significantly more cytotoxic than the tested concentrations of the extract on ECV304 human endothelial cells used as a control. Fifthy compounds were detected in GC-MS analysis of the extract, and five major compounds were predominantly found as follows: octadecanoic acid, methyl ester (27.43%); hexadecanoic acid, methyl ester (Cas) methyl palmitate (24.82%); 9,12,15-octadecatrienoic acid, ethyl ester, (Z,Z,Z)- (7.39%); octadecanoic acid (5.03%), pentadecanoic acid (3.60%). The cytotoxic activity of Dunaliella salina extract on SH-SY5Y human neuroblastoma cells might be due to high concentrations of octadecanoic acid and hexadecanoic acid. Furthermore, results indicate that the extract demonstrates some proliferative effect on ECV304 cells in a dose-dependent manner between 0.25 and 5 μg/ml. These results suggest that Dunaliella salina may have anticancer potential against human neuroblastoma cells.

  20. Characterization of novel nitrate reductase-deficient mutants for transgenic Dunaliella salina systems.

    PubMed

    Gao, L J; Jia, Y L; Li, S K; Qiu, L L

    2015-01-01

    The aim of the present study was to isolate and characterize novel nitrate reductase (NR)-deficient mutants, which may be useful for the transgenic manipulation of Dunaliella salina. Three NR-deficient mutants of D. salina, J-1, J-2, and J-3, were successfully isolated by screening for chlorate resistance after chemical mutagenesis with ethylnitrosourea. NR activity was not detected in the mutants and the expression of NR mRNA was significantly decreased. Growth analysis of D. salina strains grown in media containing different nitrogen sources revealed that these mutants were capable of utilizing nitrite and urea, but not nitrate as a nitrogen source, indicating that these mutants are indeed NR-deficient. Mutation analysis of NR cDNA sequences revealed that there were 11 point mutations shared by the J-1, J-2, and J-3 mutants. Furthermore, the results of the functional complementation experiment showed that NR activity of transformant T-1 derived from J-1 was recovered to 48.1 % of that of the wild-type D. salina. The findings of the present study indicate that nitrate may be used as a selective agent rather than antibiotics or herbicides for the isolated NR-deficient mutants in future transgenic D. salina systems.

  1. Halomarina salina sp. nov., isolated from a marine solar saltern.

    PubMed

    Xu, Wen-Mei; Xu, Jia-Qi; Zhou, Yao; Li, Yang; Lü, Zhen-Zhen; Hou, Jing; Zhu, Lin; Cui, Heng-Lin

    2016-08-01

    A halophilic archaeal strain, designated ZS-57-S(T), was isolated from Zhoushan marine solar saltern, China. Cells were observed to be pleomorphic, stained Gram-negative and formed red pigmented colonies on agar plates. Optimal growth was obtained at 3.9 M NaCl (range 1.4-4.8 M), 0.3 M MgCl2 (range 0-1.0 M), 30 °C (range 20-55 °C) and pH 6.5-7.5 (range 5.5-9.0). The cells were found to lyse in distilled water and the minimal NaCl concentration to prevent cell lysis was determined to be 5 % (w/v). The major polar lipids were identified as C20C20 and C20C25 diether derivatives of phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate, glucosyl mannosyl glucosyl diether and two unidentified glycolipids. The 16S rRNA gene and rpoB' gene of strain ZS-57-S(T) were phylogenetically related to the corresponding genes of Halomarina oriensis JCM 16495(T) (98.2 and 93.7 % similarities, respectively). The DNA G+C content of strain ZS-57-S(T) was determined to be 67.1 mol% (T m). The phenotypic, chemotaxonomic and phylogenetic properties suggested that strain ZS-57-S(T) (=CGMCC 1.12543(T) = JCM 30039(T)) represents a new species of the genus Halomarina, for which the name Halomarina salina sp. nov. is proposed. PMID:27198657

  2. Isolation and proteomic analysis of the halotolerant alga Dunaliella salina flagella using shotgun strategy.

    PubMed

    Jia, Yanlong; Xue, Lexun; Li, Jie; Liu, Hongtao

    2010-02-01

    Previous studies have demonstrated that flagella/cilia are critical organelles and play diverse roles of motility, sensory perception and development in many eukaryotic cells. However, there is very little information available about flagella composition in Dunaliella salina, a halotolerant, unicellular biflagellate green alga. In the present study, we used strategy of shotgun proteomics to identify flagella proteins after flagella were released and collected from D. salina. A total of 520 groups of proteins were identified under a stringent filter condition (Xcorr > or =1.9, > or =2.2 and > or =3.75; DeltaCn >/= 0.1). In addition to six kinds of known flagella proteins, the putative flagella proteins of D. salina identified by one or more peptides are abundant in signaling, cell division, metabolism, etc. The findings provide guidance for further studies to elucidate the roles of these proteins in the function and assembly of this organelle in microalgae.

  3. A dynamic growth model of Dunaliella salina: parameter identification and profile likelihood analysis.

    PubMed

    Fachet, Melanie; Flassig, Robert J; Rihko-Struckmann, Liisa; Sundmacher, Kai

    2014-12-01

    In this work, a photoautotrophic growth model incorporating light and nutrient effects on growth and pigmentation of Dunaliella salina was formulated. The model equations were taken from literature and modified according to the experimental setup with special emphasis on model reduction. The proposed model has been evaluated with experimental data of D. salina cultivated in a flat-plate photobioreactor under stressed and non-stressed conditions. Simulation results show that the model can represent the experimental data accurately. The identifiability of the model parameters was studied using the profile likelihood method. This analysis revealed that three model parameters are practically non-identifiable. However, some of these non-identifiabilities can be resolved by model reduction and additional measurements. As a conclusion, our results suggest that the proposed model equations result in a predictive growth model for D. salina.

  4. Analysis of an essential carotenogenic enzyme: ζ-carotene desaturase from unicellular Alga Dunaliella salina.

    PubMed

    Ye, Zhi-Wei; Jiang, Jian-Guo

    2010-11-10

    The green alga Dunaliella has become a valuable model organism for understanding the interesting mechanism of massive carotenoid accumulation. Previously, DNA sequences of several carotenogenic enzymes were obtained from Dunaliella. In this study, the cDNA of zds was isolated from Dunaliella salina using a polymerase chain reaction approach. The full-length cDNA sequence was 2178 base pairs (bp) containing a 1731 bp putative open reading frame which coded a 576 amino acid deduced polypeptide whose molecular weight was 63.9 kDa computationally. A complete homologous search displayed that the nucleotide and putative protein sequence have sequence identities of 69% and 66% with those of green alga Chlamydomonas reinhardtii, respectively. It was predicted that this ζ-carotene desaturase (Zds) may be located in the chloroplast of D. salina. Phylogenetic analysis demonstrated that the D. salina Zds had a closer relationship with the Zds of algae and higher plants than with those of other species.

  5. A novel glyceraldehyde-3-phosphate dehydrogenase (GAPDH) promoter for expressing transgenes in the halotolerant alga Dunaliella salina.

    PubMed

    Jia, Yanlong; Li, Shenke; Allen, George; Feng, Shuying; Xue, Lexun

    2012-05-01

    A major challenge for efficient transgene expression in Dunaliella salina is to find strong endogenous promoters to drive the transgene expression. In the present study, a novel glyceraldehyde-3-phosphate dehydrogenase (GAPDH) promoter was cloned and used to drive expressions of the bialaphos resistance (bar) gene and of the N-terminal fragment of human canstatin (Can-N). The results showed that the bar gene was transcribed by the GAPDH promoter and integrated into the genome of the transformants of D. salina. Furthermore, the PCR identification, Southern and western blots indicated that Can-N was expressed in transgenic D. salina, demonstrating that the promoter of the D. salina GAPDH gene is suitable for driving expression of heterologous genes in transgenic D. salina.

  6. Physical, biochemical and functional characterization of haemoglobin from three strains of Artemia.

    PubMed

    Sugumar, Vasudevan; Munuswamy, Natesan

    2007-02-01

    The brine shrimp, Artemia, an inhabitant of coastal and inland salterns, encounter fluctuations in the salinity which in turn influences the oxygen availability of their habitat. Hence, experiments were performed to analyze variations in haemoglobin structure and patterns of three strains of Artemia from South India and also to reflect the effect of varying oxygen levels in their habitat. Haemoglobins were purified on a DEAE-Sephadex column and haemoglobin types were analyzed by comparing their relative mobility on a non-denaturing medium. Furthermore, their molecular masses were determined by gel filtration in Sepharose column and by dodecylsulfate polyacrylamide gel electrophoresis. Results clearly reveal the presence of three distinct extracellular haemoglobins Hb I, Hb II and Hb III in Tuticorin strain while the other strains displayed only trails or the complete absence of Hb III and Hb II. Estimated molecular masses of these haemoglobins are 235,000-250,000 Da. Denaturation of the reduced and alkylated haemoglobins revealed apparently one polypeptide chain with a molecular mass of 124,000 Da. Upon denaturing gel electrophoresis of native haemoglobin Hb II, it was found that the 124,000 Da, polypeptide was cleaved specifically into two unequally-sized fragments of 50,400 and 79,800 Da. With regard to oxygen affinity, Hb III has a very high affinity for oxygen, an almost negligible Bohr effect and a good physiological adaptation to temperature changes. By combining the three haemoglobins in different proportions Artemia strains must be able to withstand diverging environmental conditions. In particular, the absence of Hb III in Puthalam and its occurrence as a faint band in Thamaraikulam could be correlated to the oxygen levels of their habitats. PMID:17185017

  7. Diapause termination and development of encysted Artemia embryos: roles for nitric oxide and hydrogen peroxide.

    PubMed

    Robbins, Heather M; Van Stappen, Gilbert; Sorgeloos, Patrick; Sung, Yeong Yik; MacRae, Thomas H; Bossier, Peter

    2010-05-01

    Encysted embryos (cysts) of the brine shrimp Artemia undergo diapause, a state of profound dormancy and enhanced stress tolerance. Upon exposure to the appropriate physical stimulus diapause terminates and embryos resume development. The regulation of diapause termination and post-diapause development is poorly understood at the molecular level, prompting this study on the capacity of hydrogen peroxide (H(2)O(2)) and nitric oxide (NO) to control these processes. Exposure to H(2)O(2) and NO, the latter generated by the use of three NO generators, promoted cyst development, emergence and hatching, effects nullified by catalase and the NO scavenger 2-phenyl-4,4,5,5,-tetramethylimidazoline-1-oxyl 3-oxide (PTIO). The maximal effect of NO and H(2)O(2) on cyst development was achieved by 4 h of exposure to either chemical. NO was effective at a lower concentration than H(2)O(2) but more cysts developed in response to H(2)O(2). Promotion of development varied with incubation conditions, indicating for the first time a population of Artemia cysts potentially arrested in post-diapause and whose development was activated by either H(2)O(2) or NO. A second cyst sub-population, refractory to hatching after prolonged incubation, was considered to be in diapause, a condition broken by H(2)O(2) but not NO. These observations provide clues to the molecular mechanisms of diapause termination and development in Artemia, while enhancing the organism's value in aquaculture by affording a greater understanding of its growth and physiology. PMID:20400630

  8. Effects of rotenone and other mitochondrial complex I inhibitors on the brine shrimp Artemia.

    PubMed

    Vehovszky, Agnes; Szabó, Henriette; Acs, A; Gyori, J; Farkas, Anna

    2010-12-01

    (Artemia) nauplii was used to asses the toxicity of rotenone, MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine), MP+ (1-methyl-4-phenylpyridinium) and the effect of L-DOPA co-treatment with rotenone. Rotenone had a dose dependent effect on mortality (LC₅₀: 0.37 ± 0.04 μM mean ± S E, n = 24), while MPTP and MP+ proved to be toxic in millimolar range (LC₅₀: 0.21 ± 0.09 mM and 0.20 ± 0.08 mM, respectively, n = 4). L-DOPA (50-200 μM) co-treatment increased the survival of the rotenone-treated animals (LC₅₀: 0.51 ± 0.23 μM, 1.03 ± 0.66 μM, and 0.76 ± 0.52 μM, respectively). In the whole body tissue homogenates of Artemia, sublethal (up to 0.3 μM) concentrations of rotenone increased the glutathione S-transferase (GST) activity by up to 50 about percent (LC₅₀: 53.3 ± 6.8 nM/min/mg protein, against 34.7 ± 3.6 nM/min/mg protein, n = 4). Nauplii treated in 100 mM L-DOPA and rotenone together showed further increase of GST activity all across the range of rotenone concentrations. These results on Artemia nauplii show similarities with other animal models, when complex I inhibitors were tested. Biochemical measurements suggest a protective role of L-DOPA by increasing the GST activity as part of the intracellular defences during toxin-evoked oxidative stress. PMID:21112832

  9. May arsenic pollution contribute to limiting Artemia franciscana invasion in southern Spain?

    PubMed Central

    Taggart, Mark A.; Green, Andy J.

    2016-01-01

    Limited information exists regarding the complex interactions between biological invasions, pollution, and climate change. Most studies indicate that pollution tends to favor invasive species. Here, we provide evidence that arsenic (As) pollution may have a role in limiting the invasion of the exotic brine shrimp Artemia franciscana. We tested As toxicity in natural populations of Artemia parthenogenetica (a native taxon) and A. franciscana from localities in southern Spain with differing degrees of As contamination. Tests were conducted both under current mean temperature conditions (25 °C), and as per a future climate scenario (i.e., an increase in mean temperature of 4 °C). Acute toxicity was estimated on the basis of the median lethal concentration (at 24 h), and chronic toxicity was evaluated by measuring Artemia survival and growth under sublethal exposures (after 26 days). At 25 °C, native A. parthenogenetica from the highly polluted Odiel and Tinto estuary was much more resistant to acute As stress (LC50-24 h, 24.67 mg L−1) than A. franciscana (15.78 mg L−1) and A. parthenogenetica from unpolluted sites (12.04 mg L−1)–suggesting that local adaptation to polluted conditions may occur. At 29 °C, resistance of A. parthenogenetica from Odiel decreased significantly, and there were no statistical differences in sensitivity between the three species/populations, suggesting that climate change may enhance the probability of invasion. Resistance increased with developmental stage from nauplii to adults, and was extremely high in cysts which still hatched at As concentrations of up to 6400 mg L−1. Under sublethal chronic exposure A. franciscana performed better (survival and growth) than A. parthenogenetica, and both species experienced a faster growth when exposed to As, compared with unexposed (control) individuals, probably due to the hormesis. We discuss the ecological implications of our results. PMID:26925327

  10. May arsenic pollution contribute to limiting Artemia franciscana invasion in southern Spain?

    PubMed

    Sánchez, Marta I; Petit, Cathleen; Martínez-Haro, Mónica; Taggart, Mark A; Green, Andy J

    2016-01-01

    Limited information exists regarding the complex interactions between biological invasions, pollution, and climate change. Most studies indicate that pollution tends to favor invasive species. Here, we provide evidence that arsenic (As) pollution may have a role in limiting the invasion of the exotic brine shrimp Artemia franciscana. We tested As toxicity in natural populations of Artemia parthenogenetica (a native taxon) and A. franciscana from localities in southern Spain with differing degrees of As contamination. Tests were conducted both under current mean temperature conditions (25 °C), and as per a future climate scenario (i.e., an increase in mean temperature of 4 °C). Acute toxicity was estimated on the basis of the median lethal concentration (at 24 h), and chronic toxicity was evaluated by measuring Artemia survival and growth under sublethal exposures (after 26 days). At 25 °C, native A. parthenogenetica from the highly polluted Odiel and Tinto estuary was much more resistant to acute As stress (LC50-24 h, 24.67 mg L(-1)) than A. franciscana (15.78 mg L(-1)) and A. parthenogenetica from unpolluted sites (12.04 mg L(-1))-suggesting that local adaptation to polluted conditions may occur. At 29 °C, resistance of A. parthenogenetica from Odiel decreased significantly, and there were no statistical differences in sensitivity between the three species/populations, suggesting that climate change may enhance the probability of invasion. Resistance increased with developmental stage from nauplii to adults, and was extremely high in cysts which still hatched at As concentrations of up to 6400 mg L(-1). Under sublethal chronic exposure A. franciscana performed better (survival and growth) than A. parthenogenetica, and both species experienced a faster growth when exposed to As, compared with unexposed (control) individuals, probably due to the hormesis. We discuss the ecological implications of our results. PMID:26925327

  11. Evolutionary Origin and Phylogeography of the Diploid Obligate Parthenogen Artemia parthenogenetica (Branchiopoda: Anostraca)

    PubMed Central

    Green, Andy J.; Figuerola, Jordi; Amat, Francisco; Rico, Ciro

    2010-01-01

    Background Understanding the evolutionary origin and the phylogeographic patterns of asexual taxa can shed light on the origin and maintenance of sexual reproduction. We assessed the geographic origin, genetic diversity, and phylogeographic history of obligate parthenogen diploid Artemia parthenogenetica populations, a widespread halophilic crustacean. Methodology/Principal Findings We analysed a partial sequence of the Cytochrome c Oxidase Subunit I mitochondrial gene from an extensive set of localities (including Eurasia, Africa, and Australia), and examined their phylogeographic patterns and the phylogenetic relationships of diploid A. parthenogenetica and its closest sexual relatives. Populations displayed an extremely low level of mitochondrial genetic diversity, with one widespread haplotype shared by over 79% of individuals analysed. Phylogenetic and phylogeographic analyses indicated a multiple and recent evolutionary origin of diploid A. parthenogenetica, and strongly suggested that the geographic origin of parthenogenesis in Artemia was in Central Asia. Our results indicate that the maternal sexual ancestors of diploid A. parthenogenetica were an undescribed species from Kazakhstan and A. urmiana. Conclusions/Significance We found evidence for multiple origin of parthenogenesis in Central Asia. Our results indicated that, shortly after its origin, diploid A. parthenogenetica populations underwent a rapid range expansion from Central Asia towards the Mediterranean region, and probably to the rest of its current geographic distribution. This contrasts with the restricted geographic distribution, strong genetic structure, and regional endemism of sexual Artemia lineages and other passively dispersed sexual continental aquatic invertebrates. We hypothesize that diploid parthenogens might have reached their current distribution in historical times, with a range expansion possibly facilitated by an increased availability of suitable habitat provided by

  12. The brine shrimp ( Artemia parthenogenetica) as encapsulation organism for prophylactic chemotherapy of fish and prawn

    NASA Astrophysics Data System (ADS)

    Cao, Ji-Xiang; Bian, Bo-Zhong; Li, Ming-Ren

    1996-06-01

    Brine shrimp ( Artemia parthenogenetica) which had ingested three water-insoluble antibacterial drugs i.e. sulfadiazine(SD), oxytetracycline (OTC) and erythromycin estolate (ERY-Es) were fed to Tilapia and Mysis III of Penaeus orientalis K. The drug contents in the predators were then determined. After administration of drugs to Tilapia and Mysis III, through the bio-encapsulation of the brine shrimp, efficacious therapeutical concentration of OTC and ERY-Es (but not SD) in the predators could be reached and maintained for more than 8 hours.

  13. The structure of Artemia sp. (brine shrimp) haemoglobins. Purification of a structural unit to homogeneity.

    PubMed Central

    Moens, L; Van Hauwaert, M L; Wolf, G

    1985-01-01

    The extracellular haemoglobins (Mr 260 000) of the brine shrimp Artemia sp. were cleaved by limited digestion with subtilisin. Structural units of Mr 16 000, which can bind dioxygen reversibly, were isolated. Analysis of the 16 000-Mr fraction (E) reveals the presence of a limited number of structural units. A single type of structural unit, E1 (Mr 15 800; pI4.8), was purified to homogeneity and characterized. Images Fig. 1. Fig. 3. Fig. 4. Fig. 5. PMID:4004806

  14. Influence of a long duration exposure, 69 months, to the space flight factors in Artemia cysts, tobacco and rice seeds

    NASA Astrophysics Data System (ADS)

    Planel, H.; Gaubin, Y.; Pianezzi, B.; Delpoux, M.; Bayonove, J.; Bès, J. C.; Heilmann, C.; Gasset, G.

    1994-10-01

    Three french laboratories have participated in the Free Flyer Biostack experiment. Artemia cysts, tobacco seeds and rice caryopsis and embryos were used. Biological objects in monolayers were dead. In opposite, a large fraction of samples used in bulk survived. A stimulatory effect occurred in the first steps of development in Artemia cysts. In fact, the larval survival was unchanged or slightly reduced. In tobacco a drastic decrease in germination and survival rate was observed. Space flight did not induce genetic changes. In rice, results depend on the variety which was investigated; the growth rate stimulation in flight samples is discussed with respect to controls.

  15. Culturing larvae of marine invertebrates.

    PubMed

    Strathmann, Richard R

    2014-01-01

    Larvae of marine invertebrates cultured in the laboratory experience conditions that they do not encounter in nature, but development and survival to metamorphic competence can be obtained in such cultures. This protocol emphasizes simple methods suitable for a wide variety of larvae. Culturing larvae requires seawater of adequate quality and temperature within the tolerated range. Beyond that, feeding larvae require appropriate food, but a few kinds of algae and animals are sufficient as food for diverse larvae. Nontoxic materials include glass, many plastics, hot-melt glue, and some solvents, once evaporated. Cleaners that do not leave toxic residues after rinsing include dilute hydrochloric or acetic acid, sodium hypochlorite (commercial bleach), and ethanol. Materials that can leave toxic residues, such as formaldehyde, glutaraldehyde, detergents, and hand lotions, should be avoided, especially with batch cultures that lack continuously renewed water. Reverse filtration can be used to change water gently at varying frequencies, depending on temperature and the kinds of food that are provided. Bacterial growth can be limited by antibiotics, but antibiotics are often unnecessary. Survival and growth are increased by low concentrations of larvae and stirring of large or dense cultures. One method of stirring large numbers of containers is a rack of motor-driven paddles. Most of the methods and materials are inexpensive and portable. If necessary, a room within a few hours of the sea could be temporarily equipped for larval culture. PMID:24567204

  16. Satellite DNA from the brine shrimp Artemia affects the expression of a flanking gene in yeast.

    PubMed

    Maiorano, D; Cece, R; Badaracco, G

    1997-04-11

    We have previously revealed that in the brine shrimp Artemia franciscana an AluI DNA family of repeats, 113 bp in length, is the major component of the constitutive heterochromatin and that this repetitive DNA shows a stable curvature that confers a solenoidal geometry on the double helix in vitro. It was suggested that this particular structure may play a relevant role in determining the condensation of the heterochromatin. In this report we have cloned hexamers of highly-repetitive sequence (AluI-satellite DNA) in proximity to a yeast lacZ reporter gene on a plasmid. We find that the expression of the reporter gene is affected by the presence of this DNA in a dose- and orientation-dependent manner in the yeast, S. cerevisiae. We show that this effect is not dependent on under-replication or re-arrangements of the repetitive DNA in the cell but is due to decreased expression of the reporter gene. Our results indicate that the AluI-satellite DNA of Artemia per se is able to influence gene expression. PMID:9161405

  17. Satellite DNA from the brine shrimp Artemia affects the expression of a flanking gene in yeast.

    PubMed

    Maiorano, D; Cece, R; Badaracco, G

    1997-04-11

    We have previously revealed that in the brine shrimp Artemia franciscana an AluI DNA family of repeats, 113 bp in length, is the major component of the constitutive heterochromatin and that this repetitive DNA shows a stable curvature that confers a solenoidal geometry on the double helix in vitro. It was suggested that this particular structure may play a relevant role in determining the condensation of the heterochromatin. In this report we have cloned hexamers of highly-repetitive sequence (AluI-satellite DNA) in proximity to a yeast lacZ reporter gene on a plasmid. We find that the expression of the reporter gene is affected by the presence of this DNA in a dose- and orientation-dependent manner in the yeast, S. cerevisiae. We show that this effect is not dependent on under-replication or re-arrangements of the repetitive DNA in the cell but is due to decreased expression of the reporter gene. Our results indicate that the AluI-satellite DNA of Artemia per se is able to influence gene expression.

  18. Pesticide Risk Communication, Risk Perception, and Self-Protective Behaviors among Farmworkers in California's Salinas Valley

    ERIC Educational Resources Information Center

    Cabrera, Nolan L.; Leckie, James O.

    2009-01-01

    Agricultural pesticide use is the highest of any industry, yet there is little research evaluating farmworkers' understandings of the health risks chemical exposure poses. This study examines pesticide education, risk perception, and self-protective behaviors among farmworkers in California's Salinas Valley. Fifty current and former farmworkers…

  19. 76 FR 18547 - Grand River Dam Authority, Salina Pumped Storage Project; Notice of Proposed Restricted Service...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-04

    ... Inclusion in the National Register of Historic Places Rule 2010 of the Federal Energy Regulatory Commission... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Grand River Dam Authority, Salina Pumped Storage Project; Notice of...

  20. Hepatoprotective and Antioxidant Activity of Dunaliella salina in Paracetamol-induced Acute Toxicity in Rats

    PubMed Central

    Madkour, Fedekar F.; Abdel-Daim, M. M.

    2013-01-01

    Paracetamol has a reasonable safety profile when taken in therapeutic doses. However, it could induce hepatotoxicity and even more severe fatal acute hepatic damage when taken in an overdose. The green alga, Dunaliella salina was investigated for hepatoprotective and antioxidant activity against paracetamol-induced liver damage in rats. Male albino Wistar rats overdosed with paracetamol showed liver damage and oxidative stress as indicated by significantly (P<0.05) increased serum levels of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, total and direct bilirubin, malondialdehyde, cholesterol and nitric oxide. At the same time, there were decreased activities of serum superoxide dismutase and total antioxidant capacity compared with the control group. Treatment with D. salina methanol extract at doses of 500 and 1000 mg/kg body weight or silymarin could significantly (P<0.05) decrease the liver damage marker enzymes, total and direct bilirubin, malondialdehyde, cholesterol and nitric oxide levels and increase the activities of superoxide dismutase and total antioxidant capacity in serum when compared with paracetamol intoxicated group. Liver histopathology also showed that D. salina reduced the centrilobular necrosis, congestion and inflammatory cell infiltration evoked by paracetamol overdose. These results suggest that D. salina exhibits a potent hepatoprotective effect on paracetamol-induced liver damage in rats, which may be due to both the increase of antioxidant enzymes activity and inhibition of lipid peroxidation. PMID:24591738

  1. Biochemical composition and bioactivity screening of various extracts from Dunaliella salina, a green microalga.

    PubMed

    Cakmak, Yavuz Selim; Kaya, Murat; Asan-Ozusaglam, Meltem

    2014-01-01

    The current study examines the antimicrobial and antioxidant properties of different extracts of the microalga Dunaliella salina Teodoresco (Dunaliellaceae), their fatty acid composition and the antimicrobial activity of the oil. Antimicrobial and antioxidant activities were evaluated by obtaining extracts of D. salina in n-hexane, dichloromethane, ethanol, and methanol. To evaluate the antimicrobial activity, the extracts, and fatty acids from D. salina were assessed by the disc diffusion and microdilution techniques against pathogenic microorganisms including fish and clinical/food-borne. The MBC or MFC values of the extracts and fatty acids ranged from 0.63 to 10.00 mg/ml. The antioxidant activity was studied by phosphomolybdenum and DPPH assays and ß-carotene/linoleic acid tests. In addition, the total phenolic and flavonoid contents were evaluated and the fatty acid composition was determined using gas chromatography. Palmitic, alpha-linolenic, and oleic acids were discovered to be the major components of the fatty acids. These findings have demonstrated that the extracts and oil from D. salina could be used as natural antimicrobials and antioxidants in the food/feed and pharmaceutical industry and as a biodiesel because of its high unsaturated fatty acid content.

  2. ANALYSIS OF EXPRESSED SEQUENCE TAGS FROM THE GREEN ALGA DUNALIELLA SALINA (CHLOROPHYTA)(1).

    PubMed

    Zhao, Rui; Cao, Yu; Xu, Hui; Lv, Linfeng; Qiao, Dairong; Cao, Yi

    2011-12-01

    The unicellular green alga Dunaliella salina (Dunal) Teodor. is a novel model photosynthetic eukaryote for studying photosystems, high salinity acclimation, and carotenoid accumulation. In spite of such significance, there have been limited studies on the Dunaliella genome transcriptome and proteome. To further investigate D. salina, a cDNA library was constructed and sequenced. Here, we present the analysis of the 2,282 expressed sequence tags (ESTs) generated together with 3,990 ESTs from dbEST. A total of 4,148 unique sequences (UniSeqs) were identified, of which 56.1% had sequence similarity with Uniprot entries, suggesting that a large number of unique genes may be harbored by Dunaliella. Additionally, protein family domains were identified to further characterize these sequences. Then, we also compared EST sequences with different complete eukaryotic genomes from several animals, plants, and fungi. We observed notable differences between D. salina and other organisms. This EST collection and its annotation provided a significant resource for basic and applied research on D. salina and laid the foundation for a systematic analysis of the transcriptome basis of green algae development and diversification.

  3. Regulation of virus-induced inflammatory response by Dunaliella salina alga extract in macrophages.

    PubMed

    Lin, Hui-Wen; Chen, Yi-Chen; Liu, Cheng-Wei; Yang, Deng-Jye; Chen, Shih-Yin; Chang, Tien-Jye; Chang, Yuan-Yen

    2014-09-01

    Previous reports have suggested that many constituents within various algal samples are able to attenuate LPS-induced inflammatory effects. To date no report has been published on the regulation of virus-induced inflammatory response of Dunaliella salina carotenoid extract. In the present study, the anti-inflammatory effect of D. salina carotenoid extract on pseudorabies virus (PRV)-infected RAW 264.7 macrophages was investigated. We evaluated the anti-inflammatory effect of D. salina carotenoid extract on PRV-infected RAW 264.7 cells by measuring cell viability, cytotoxicity, production of inflammatory mediators such as NO, iNOS, COX-2, pro-inflammatory cytokines and anti-virus replication by plaque assay. We found down-regulation of the expression of the iNOS, COX-2 and pro-inflammatory genes IL-1β, IL-6, TNF-α, and MCP-1 in a dose-dependent manner. Although there was no effect on viral replication, there were tendencies toward lower virus titer and tendencies toward higher cell survival. Most importantly, we found that inhibition of TLR9, PI3K and Akt phosphorylation plays a crucial role in the extract-mediated NF-κB regulation by modulating IKK-IκB signaling in PRV-infected RAW264.7 cells. These results indicate that D. salina carotenoid extracts inhibited inflammation by inhibition of NF-κB activation by TLR9 dependent via PI3K/Akt inactivation.

  4. Hepatoprotective and Antioxidant Activity of Dunaliella salina in Paracetamol-induced Acute Toxicity in Rats.

    PubMed

    Madkour, Fedekar F; Abdel-Daim, M M

    2013-11-01

    Paracetamol has a reasonable safety profile when taken in therapeutic doses. However, it could induce hepatotoxicity and even more severe fatal acute hepatic damage when taken in an overdose. The green alga, Dunaliella salina was investigated for hepatoprotective and antioxidant activity against paracetamol-induced liver damage in rats. Male albino Wistar rats overdosed with paracetamol showed liver damage and oxidative stress as indicated by significantly (P<0.05) increased serum levels of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, total and direct bilirubin, malondialdehyde, cholesterol and nitric oxide. At the same time, there were decreased activities of serum superoxide dismutase and total antioxidant capacity compared with the control group. Treatment with D. salina methanol extract at doses of 500 and 1000 mg/kg body weight or silymarin could significantly (P<0.05) decrease the liver damage marker enzymes, total and direct bilirubin, malondialdehyde, cholesterol and nitric oxide levels and increase the activities of superoxide dismutase and total antioxidant capacity in serum when compared with paracetamol intoxicated group. Liver histopathology also showed that D. salina reduced the centrilobular necrosis, congestion and inflammatory cell infiltration evoked by paracetamol overdose. These results suggest that D. salina exhibits a potent hepatoprotective effect on paracetamol-induced liver damage in rats, which may be due to both the increase of antioxidant enzymes activity and inhibition of lipid peroxidation.

  5. Carbon source utilization by the marine Dendryphiella species D. arenaria and D. salina.

    PubMed

    dela Cruz, Thomas Edison E; Schulz, Barbara E; Kubicek, Christian P; Druzhinina, Irina S

    2006-12-01

    Carbon utilization by the marine Dendryphiella species, D. arenaria and D. salina, was investigated to detect differences in utilization and traits associated with their adaptation to the marine habitat. Fifty-four strains were isolated world-wide and tested for the utilization of various carbon sources using BIOLOG phenotype MicroArray (PM) and for the production of extracellular enzymes on solid culture media and on API ZYM assay strips. PM analysis showed that the fastest growth occurred on several monosaccharides and amino acids, 2-keto-d-gluconic acid, succinamide and turanose. Some polyols were poor carbon sources. However, the two species differed in their utilization rates of carbon sources, forming three major clusters: two separate clusters for D. arenaria and D. salina and a third cluster in which strains of the two species formed separate subclades that correlated with geographic origin. Several carbon sources were also found useful in differentiating the two speices. Dendryphiella salina did not utilize xylitol and quinic acid, whereas D. arenaria grew well on these substrates. The latter failed to grow on sorbitol and grew slowly on mannitol, both were good substrates for the former. There were also no qualitative differences between the extracellular enzymes produced, although laccase and peroxidase activities were confined only to some strains. The physiological similarities exhibited by the two species support the close relationship between D. arenaria and D. salina.

  6. Intentional introduction of Artemia sinica (Anostraca) in the high-altitude Tibetan lake Dangxiong Co: the new population and consequences for the environment and for humans

    NASA Astrophysics Data System (ADS)

    Jia, Qinxian; Anufriieva, Elena; Liu, Xifang; Kong, Fanjing; Shadrin, Nickolai

    2015-11-01

    The imbalance between supply and demand of Artemia cysts in China and around the world is increasing now. Salt lakes in Tibet may contribute to the solution of the problem. In Northern Tibet there are 26 saline lakes whose salinity and temperature may support Artemia survival at an altitude of 4 000-5 100 m. We found Artemia in 15 of these lakes. The saline lakes with Artemia populations mainly belong to the shallow basin lakes, and the majority of these lakes are small in area. The total area of lakes without Artemia is more than 1 000 km2. Lake Dangxiong Co (Co means lake in Tibet) was chosen for the intentional introduction of Artemia sinica. In 2004, 850 g of A. sinica cysts, originating from Qinghai, were introduced in the lake. Surveys in 2006-2014 showed that the average abundance of Artemia adults in the lake gradually increased from 20 ind./m3 in 2006 to 1950 ind./m3 in 2013. We assume that two subpopulations of A. sinica, separated by depth, may exist in the lake. The new Artemia population caused an increase in the number of species of phytoplankton and heterotrophic protozoa with a decrease of their total abundance. Water transparency also increased. Dominance in phytoplankton passed from cyanobacteria to diatoms. Changes occurred not only in the lake ecosystem; the number of water birds using the lakes also dramatically increased. Preliminary calculations showed that is it possible to harvest at least about 150 t cysts per year from the lake as well as 3.2 thousand tons of frozen or 350 t of dried biomass of adult Artemia.

  7. Groundwater quality in the Monterey Bay and Salinas Valley groundwater basins, California

    USGS Publications Warehouse

    Kulongoski, Justin T.; Belitz, Kenneth

    2011-01-01

    The Monterey-Salinas study unit is nearly 1,000 square miles and consists of the Santa Cruz Purisima Formation Highlands, Felton Area, Scotts Valley, Soquel Valley, West Santa Cruz Terrace, Salinas Valley, Pajaro Valley, and Carmel Valley groundwater basins (California Department of Water Resources, 2003; Kulongski and Belitz, 2011). These basins were grouped into four study areas based primarily on geography. Groundwater basins in the north were grouped into the Santa Cruz study area, and those to the south were grouped into the Monterey Bay, the Salinas Valley, and the Paso Robles study areas (Kulongoski and others, 2007). The study unit has warm, dry summers and cool, moist winters. Average annual rainfall ranges from 31 inches in Santa Cruz in the north to 13 inches in Paso Robles in the south. The study areas are drained by several rivers and their principal tributaries: the Salinas, Pajaro, and Carmel Rivers, and San Lorenzo Creek. The Salinas Valley is a large intermontane valley that extends southeastward from Monterey Bay to Paso Robles. It has been filled, up to a thickness of 2,000 feet, with Tertiary and Quaternary marine and terrestrial sediments that overlie granitic basement. The Miocene-age Monterey Formation and Pliocene- to Pleistocene-age Paso Robles Formation, and Pleistocene to Holocene-age alluvium contain freshwater used for supply. The primary aquifers in the study unit are defined as those parts of the aquifers corresponding to the perforated intervals of wells listed in the California Department of Public Health database. Public-supply wells are typically drilled to depths of 200 to 650 feet, consist of solid casing from the land surface to depths of about 175 to 500 feet, and are perforated below the solid casing. Water quality in the primary aquifers may differ from that in the shallower and deeper parts of the aquifer system. Groundwater movement is generally from the southern part of the Salinas Valley north towards the Monterey Bay

  8. Selected Bacterial Strains Protect Artemia spp. from the Pathogenic Effects of Vibrio proteolyticus CW8T2

    PubMed Central

    Verschuere, Laurent; Heang, Hanglamong; Criel, Godelieve; Sorgeloos, Patrick; Verstraete, Willy

    2000-01-01

    In this study Vibrio proteolyticus CW8T2 has been identified as a virulent pathogen for Artemia spp. Its infection route has been visualized with transmission electron microscopy. The pathogen affected microvilli and gut epithelial cells, disrupted epithelial cell junctions, and reached the body cavity, where it devastated cells and tissues. In vivo antagonism tests showed that preemptive colonization of the culture water with nine selected bacterial strains protected Artemia juveniles against the pathogenic effects. Two categories of the selected strains could be distinguished: (i) strains providing total protection, as no mortality occurred 2 days after the experimental infection with V. proteolyticus CW8T2, with strain LVS8 as a representative, and (ii) strains providing partial protection, as significant but not total mortality was observed, with strain LVS2 as a representative. The growth of V. proteolyticus CW8T2 in the culture medium was slowed down in the presence of strains LVS2 and LVS8, but growth suppression was distinctly higher with LVS8 than with LVS2. It was striking that the strains that gave only partial protection against the pathogen in the in vivo antagonism test showed also a restricted capability to colonize the Artemia compared to the strains providing total protection. The in vivo antagonism tests and the filtrate experiments showed that probably no extracellular bacterial compounds were involved in the protective action but that the living cells were required to protect Artemia against V. proteolyticus CW8T2. PMID:10698783

  9. Does a change from whole to powdered food (Artemia franciscana eggs) increase oviposition in the ladybird Coleomegilla maculata?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The limited availability of alternative foods to replace natural prey hinders cost-effective mass production of ladybird beetles for augmentative biological control. We compared the effects of powdered versus whole Artemia franciscana (brine shrimp) eggs with or without a dietary supplement on devel...

  10. Susceptibility of the brine shrimp Artemia and its pathogen Vibrio parahaemolyticus to chlorine dioxide in contaminated sea-water.

    PubMed

    Puente, M E; Vega-Villasante, F; Holguin, G; Bashan, Y

    1992-12-01

    Adults and nauplii of the brine shrimp, Artemia, together with Vibrio parahaemolyticus, were placed in sewage-contaminated sea-water which had been treated with chlorine dioxide (Hallox E-100TM) to test its potential as a disinfectant for salt water aquaculture. The nauplii were very susceptible to low concentrations of chlorine dioxide (47 micrograms/l Cl-), but the adults were slightly more resistant. Sterile sea-water treated with lower concentrations of chlorine dioxide (less than 47 micrograms/l Cl-) had no effect on the shrimp, but inhibited the growth of V. parahaemolyticus. In sewage-contaminated sea-water, chlorine dioxide levels of 285-2850 micrograms/l, necessary for the inactivation of V. parahaemolyticus and any native bacteria, destroyed the Artemia culture. Hallox E-100TM persisted in sea-water for 18 h, but later decayed. We conclude that: (i) Artemia nauplii are a sensitive and convenient test-organism to determine low concentrations of chlorine dioxide in sea-water; (ii) chlorine dioxide is efficient for controlling V. parahaemolyticus in sea-water; and (iii) chlorine dioxide should be further evaluated as a potential disinfectant for aquaculture, but, for higher organisms than Artemia. PMID:1490907

  11. Evaluation of commercial Artemia enrichment products on growth, survival, stress tolerance, and fatty acid composition of larval Florida pompano

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rearing live feed organisms represents the majority of time and labor associated with larviculture operations vital to the seed stock supply of marine finfish aquaculture production facilities. No information exists with respect to optimal Artemia enrichment protocols for Florida pompano Trachinotu...

  12. Morphological differentiation of seven parthenogenetic Artemia (Crustacea: Branchiopoda) populations from China, with special emphasis on ploidy degrees.

    PubMed

    Asem, Alireza; Sun, Shi-Chun

    2016-04-01

    Parthenogenetic Artemia from seven Chinese locations with different elevations and various ploidies are characterized by phenotypic and morphometric analyses. Our findings show that the studied populations exhibit dissimilar patterns of ovisac. Four phenotypic patterns of furca are qualified and one of them is shared among di-, tetra- and pentaploid Artemia. Results of discriminant analysis based on morphometric data reveal that tetra- and pentaploid populations are grouped together, but the Aqqikkol Lake population is clearly differentiated. Previous hypothesis/conclusion that polyploid Artemia are larger than diploids is only partly supported by the present results, which show that pentaploid and tetraploid populations are larger than the mostly diploid populations in terms of the total length, but the body size of the Aibi Lake triploids has not significant difference with the sympatric diploids and the mostly diploid Aqqikkol population that inhabit in very high altitude has the largest body size among all parthenogenetic populations. The founding confirms that body size of Artemia is following with Bergmann's rule. PMID:26777727

  13. Development of digestive enzymes in larvae of Mayan cichlid Cichlasoma urophthalmus.

    PubMed

    López-Ramírez, G; Cuenca-Soria, C A; Alvarez-González, C A; Tovar-Ramírez, D; Ortiz-Galindo, J L; Perales-García, N; Márquez-Couturier, G; Arias-Rodríguez, L; Indy, J R; Contreras-Sánchez, W M; Gisbert, E; Moyano, F J

    2011-03-01

    The development of digestive enzymes during the early ontogeny of the Mayan cichlid (Cichlasoma urophthalmus) was studied using biochemical and electrophoretic techniques. From yolk absorption (6 days after hatching: dah), larvae were fed Artemia nauplii until 15 dah, afterward they were fed with commercial microparticulated trout food (45% protein and 16% lipids) from 16 to 60 dah. Several samples were collected including yolk-sac larvae (considered as day 1 after hatching) and specimens up to 60 dah. Most digestive enzymes were present from yolk absorption (5-6 dah), except for the specific acid proteases activity (pepsin-like), which increase rapidly from 8 dah up to 20 dah. Three alkaline proteases isoforms (24.0, 24.8, 84.5 kDa) were detected at 8 dah using SDS-PAGE zymogram, corresponding to trypsin, chymotrypsin and probably leucine aminopeptidase enzymes, and only one isoform was detected (relative electromobility, Rf = 0.54) for acid proteases (pepsin-like) from 3 dah onwards using PAGE zymogram. We concluded that C. urophthamus is a precocious fish with a great capacity to digest all kinds of food items, including artificial diets provided from 13 dah.

  14. [Accumulation and transformation of different arsenic species in nonaxenic Dunaliella salina].

    PubMed

    Wang, Ya; Zhang, Chun-Hua; Wang, Shu; Shen, Lian-Yu; Ge, Ying

    2013-11-01

    Algae and bacteria are usually symbiotic in the environment. The algae-bacteria consortia have a good prospect in the remediation of polluted environment. In this study, we isolated a bacterium from nonaxenic Dunaliella salina and identified it as Bacillus solisalsi using 16S rRNA sequence analysis. The uptake, adsorption and transformation of As by the nonaxenic D. salina and the concentration and speciation of As in the culture solution were determined after 13 days exposure to various concentrations of As(III) and As( V). The results showed that D. salina had a high As tolerance. When the algae was exposed to 250 micromol x L(-1) and 500 micromol x L(-1) arsenite, As accumulations were 3.78 g x kg(-1) and 4.56 g x kg(-1), respectively, but the As removal from the solution was 7.9% - 8.3%. B. solisalsi did not show a strong ability to clean up As either (6.1%-19.9% removal rate). The consortia of D. salina and B. solisalsi showed a higher As removal ability. Moreover, 0.99-2.79 g x kg(-1) and 1.22-3.46 g x kg(-1) As were absorbed when exposed to 25-100 micromol x L(-1) and 25-500 micromol x L(-1) As(III) and As(V), respectively. More than 54.3% of As were taken away by the consortia from the solution under the exposure of 25-100 micromol x L(-1) As(III) and As(V). Various pathways of As detoxification were identified for the nonaxenic D. salina: As(III) oxidation, As(V) reduction, As(III) methylation, and efflux of As from cells.

  15. La columna, el circulo y sus variantes en la poesia primera de Pedro Salinas (The Vertical Line, the Circle, and other Geometric Varieties in the Early Poetry of Pedro Salinas)

    ERIC Educational Resources Information Center

    De Armas, Jose R.

    1970-01-01

    Interprets Salinas' use of geometric figures for depicting concepts of time and infinity, and for portraying idealism and realism (the vertical line is idealism, perfection; the circle stands for reality and imperfection). (DS)

  16. Biochemical studies on sphingolipids of Artemia franciscana: novel neutral glycosphingolipids[S

    PubMed Central

    Kojima, Hisao; Shimizu, Takemasa; Sugita, Mutsumi; Itonori, Saki; Fujita, Norihisa; Ito, Masahiro

    2011-01-01

    Neutral glycosphingolipids containing one to six sugars in their oligosaccharide chains have been isolated from cysts of the brine shrimp Artemia franciscana. The structures of these glycolipids were identified by methylation analysis, partial acid hydrolysis, gas-liquid chromatography, combined gas-liquid chromatography-mass spectrometry, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and proton nuclear magnetic resonance spectroscopy to be Glcβ1-Cer, Manβ1-4Glcβ1-Cer, Fucα1-3Manβ1-4Glcβ1-Cer, GlcNAcβ1-3Manβ1-4Glcβ1-Cer, GlcNAcα1-2Fucα1-3Manβ1-4Glcβ1-Cer, GalNAcβ1-4GlcNAcβ1-3Manβ1-4Glcβ1-Cer, GalNAcβ1-4(Fucα1-3)GlcNAcβ1-3Manβ1-4Glcβ1-Cer (CPS), and GalNAcβ1-4(GlcNAcα1-2Fucα1-3)GlcNAcβ1-3Manβ1-4Glcβ1-Cer (CHS). Two glycosphingolipids, CPS and CHS, were characterized as novel structures. Because Artemia contains a certain series of glycosphingolipids (-Fucα3Manβ4GlcβCer), which differ from the core sugar sequences reported thus far, we tentatively designated the glycosphingolipids characterized as nonarthro-series ones. Furthermore, CHS exhibited a hybrid structure of arthro-series and nonarthro-series sugar chain. Two novel glycosphingolipids were characterized from the brine shrimp Artemia franciscana; one was composed of arthrotetraose and a branching fucose attached to N-acetylglucosamine residue, and the other was composed of CPS with an additional N-acetylglucosamine residue attached to the branching fucose. PMID:21062954

  17. Multigenerational demographic responses of sexual and asexual Artemia to chronic genotoxicity by a reference mutagen.

    PubMed

    Sukumaran, Sandhya; Grant, Alastair

    2013-11-15

    Genotoxins are capable of multigenerational impacts on natural populations via DNA damage and mutations. Sexual reproduction is assumed to reduce the long term consequences of genotoxicity for individual fitness and should therefore reduce population level effects. However, rather few empirical studies have quantified the magnitude of this effect. We tried to analyse the multigenerational demographic responses of sexual Artemia franciscana and asexual Artemia parthenogenetica due to chronic genotoxicity by a reference mutagen, ethyl methane sulfonate (EMS). A prospective (elasticity analysis) and retrospective (differences and contributions) perturbation analysis was carried out to understand the interactions of life history traits with population growth rate λ by comparing elasticities, differences and contributions of vital rates to λ. None of the previous studies have compared the effects of chronic genotoxicity using prospective and retrospective perturbation analyses in a sexual and asexual species over generations. The behaviour of a population with lower growth rate in the presence of genotoxicants in the field was studied by simulating reduced fertilities in the LTRE design. The results of prospective and retrospective perturbation analyses of effects on λ showed that population growth rate was proportionally more sensitive to juvenile survival whereas the effect of EMS on juvenile fertility contributed more to the variations in population growth rate in both the species and this effect was due to the high growth rate of Artemia. Simulations of lower population growth rate in the model showed that adult fertility and survival are also of importance. Sexual reproduction substantially mitigated the long term consequences of genetic damage, although these would be greater if population growth rate were lower. So multigenerational population level consequences of genotoxicity were much greater in an asexual species. So asexual species, and those with a

  18. Interactive effect of selenium and mercury on development and mortality of brine shrimp, Artemia sp.

    SciTech Connect

    Forsythe, B.L. II; Bailey, F.C.; Klaine, S.J.

    1994-12-31

    The interactions between organic mercury and selenium derivatives are well documented. Inorganic mercury has been shown to have a deleterious effect on the development of brine shrimp, Artemia franciscana while selenate has no effect. In this study, concentrations as low as 0.1 mg/l Hg (as Hg(NO{sub 3})2) slowed the rate of development. Selenate concentrations ranging from 0.1 to 5.0 mg/l as Se decreased the effect of Hg on brine shrimp developmental rate. Both selenate and inorganic mercury alone produced a dose-response with respect to nauplii mortality. Preliminary data suggest that combinations of selenate and inorganic mercury act antagonistically to lower this mortality.

  19. Intracellular localization of group 3 LEA proteins in embryos of Artemia franciscana.

    PubMed

    Boswell, Leaf C; Hand, Steven C

    2014-12-01

    Late embryogenesis abundant (LEA) proteins are accumulated by anhydrobiotic organisms in response to desiccation and improve survivorship during water stress. In this study we provide the first direct evidence for the subcellular localizations of AfrLEA2 and AfrLEA3m (and its subforms) in anhydrobiotic embryos of Artemia franciscana. Immunohistochemistry shows AfrLEA2 to reside in the cytoplasm and nucleus, and the four AfrLEA3m proteins to be localized to the mitochondrion. Cellular locations are supported by Western blots of mitochondrial, nuclear and cytoplasmic fractions. The presence of LEA proteins in multiple subcellular compartments of A. franciscana embryos suggests the need to protect biological structures in many areas of a cell in order for an organism to survive desiccation stress, and may explain in part why a multitude of different LEA proteins are expressed by a single organism. PMID:25311474

  20. Aerobic heat shock activates trehalose synthesis in embryos of Artemia franciscana.

    PubMed

    Clegg, J S; Jackson, S A

    1992-05-25

    Encysted embryos (cysts) of the brine shrimp, Artemia franciscana, contain large amounts of trehalose which they use as a major substrate for energy metabolism and biosynthesis for development under aerobic conditions at 25 degrees C. When cysts are placed at 42 degrees C (heat shock) these pathways stop, and the cysts re-synthesize the trehalose that was utilized during the previous incubation at 25 degrees C. Glycogen and glycerol, produced from trehalose at 25 degrees C, appear to be substrates for trehalose synthesis during heat shock. Anoxia prevents trehalose synthesis in cysts undergoing heat shock. These results are consistent with the view that trehalose may play a protective role in cells exposed to heat shock, and other environmental insults, in addition to being a storage form of energy and organic carbon for development. PMID:1592115

  1. Acetogenins in Annona muricata L. (annonaceae) leaves are potent molluscicides.

    PubMed

    Luna, J De S; De Carvalho, J M; De Lima, M R F; Bieber, L W; Bento, Edson De S; Franck, X; Sant'ana, A E G

    2006-03-01

    An ethanolic extract of the leaves of Annona muricata was shown to be toxic to adult forms of the snail Biomphalaria glabrata (LC50 9.32 microg mL(-1)) and to larvae of the brine shrimp Artemia salina (LC50 0.49 microg mL(-1)). Activity-guided fractionation of the extract gave rise to a sample with high molluscicidal activity that contained the acetogenins, annonacin (90%), isoannonacin (6%) and goniothalamicin (4%).

  2. Phototoxicity of non-carcinogenic polycyclic aromatic hydrocarbons in aquatic organisms

    SciTech Connect

    Kagan, J.; Kagan, E.D.; Kagan, I.A.; Kagan, P.A.; Quigley, S.

    1985-01-01

    Anthracene, fluoranthene, and pyrene are phototoxic in Daphnia magna, Artemia salina, first instar larvae of Aedes aegypti, late embryonic forms of Rana pipiens, and fish (Pimephales promelas). Since polycyclic aromatic hydrocarbons are generated in the combustion processes held responsible for the damages of acid rain, and they are introduced into the environment through other means as well, the high phototoxicity of the major pollutants, which are not carcinogenic, suggests that greater attention must be given to their environmental significance.

  3. Arsenate toxicity and metabolism in the halotolerant microalga Dunaliella salina under various phosphate regimes.

    PubMed

    Wang, Ya; Zheng, Yanheng; Liu, Cong; Xu, Pingping; Li, Hao; Lin, Qiaoyun; Zhang, Chunhua; Ge, Ying

    2016-06-15

    Microalgae play an important role in arsenic (As) biogeochemical cycles as they are capable of accumulating and metabolizing this metalloid efficiently. This study aimed to investigate the toxicity, accumulation and transformation of arsenate (As(v)) in Dunaliella salina, an exceptionally halotolerant microalga, under various phosphate (PO4(3-)) regimes. The results of the 72-h toxicity test showed that D. salina was tolerant to As(v). In addition, the toxicity of As(v) was mitigated by an increased PO4(3-) supply. D. salina resisted the adverse effects of As(v) through the suppression of As uptake, enhancement of As reduction, methylation in the cell and excretion from the cell. Our study revealed that D. salina reduced As(v) toxicity using different strategies, i.e., reduction of As uptake upon acute As stress (24 h) and increase of As efflux following chronic As exposure (9 day). Moreover, PO4(3-) strongly affected the adsorption, uptake and transformation of As(v) in D. salina. As(v) reduction, DMA production and As excretion were enhanced under P-limited conditions (0.112 mg L(-1)) or upon higher As(v) exposure (1120 μg L(-1)). Furthermore, PO4(3-) had a significant influence on the As removal ability of D. salina. A high As removal efficiency (>95.6%) was observed in the 5-day cultures at an initial As concentration of 11.2 μg L(-1) and PO4(3-) of 0.112 and 1.12 mg L(-1). However, only 10.9% of total As was removed under 11.2 mg L(-1) PO4(3-) after 9 days of incubation. The findings of this study illustrate the pivotal roles of extracellular PO4(3-) in As(v) toxicity and metabolism, and the results may be relevant for future research on the minimization of As contamination in algal products as well as on the enhancement of As removal from the environment.

  4. Can the halophilic ciliate Fabrea salina be used as a bio-control of microalgae blooms in solar salterns?

    NASA Astrophysics Data System (ADS)

    Hong, Hyun Pyo; Choi, Joong Ki

    2015-09-01

    The microlage Dunaliella salina, a major producer in salterns, is a serious problem for salt production. In this study we tried to assess if Fabrea salina can control D. salina. By parameterising numerical and functional response (growth and grazing vs prey abundance, respectively) at 90 psu and 30°C, where the ciliate is abundant and grows well, we developed a predator-prey model. The model is used to explore how change in microalga growth rate affect the dynamics, and the functional response is used in combination with field data to assess the potential impact of F. salina on D. salina. Over the 20 d simulation the ciliate controlled the prey population under all prey growth rates; although once D. salina were exhausted below the threshold level, F. salina died due to starvation, allowing the alga to increase in abundance, resulting in one or two predatorprey cycle, depending on prey growth rate. In general, the model predicted trends observed by others in the field, suggesting that it provided a good prediction of what may occur under the conditions we examined. Likewise we show that the ciliate can have a high impact on microalgal populations in the field. Finally, a literature review indicated that F. salina could be a good competitor with other protozoa and metazoan in salterns, depending on salinity and temperature, which requires further study and attention. In summary, we encourage continued studies on this unique ciliate on solar salterns and suggest that it may be useful in the bio-control of micoalgae.

  5. Effects of salinities on the gene expression of a (NAD+)-dependent glycerol-3-phosphate dehydrogenase in Dunaliella salina.

    PubMed

    Chen, Hui; Lao, Yong-Min; Jiang, Jian-Guo

    2011-03-01

    Glycerol-3-phosphate dehydrogenase (G3pdh) is a key enzyme in the pathway of glycerol synthesis, which converts dihydroxyacetone phosphate (DHAP) to glycerol-3-phosphate. In this study, the effects of salinity changes on variation of cell shape and single cell glycerol content of Dunaliella salina were observed, and the effects of salinity changes on the gene expressions of a (NAD+)-dependent G3pdh (EC1.1.1.8) among G3pdh isozymes in D. salina were detected by real-time quantitative PCR. Results showed that the changes of shape and volume of D. salina cell cultured chronically at various salinities were minor, but when the salinity was changed rapidly, the variations of cell shape and cell volume of D. salina were significant, which were recovered basically after 2h except treating by high salinity. Also, it was found some lipid globules in the surface of D. salina cells when the salinity increased from 2.0 to 4.0-5.0 M NaCl rapidly. When D. salina was cultured chronically at various salinities, the accumulation of single cell glycerol increased with increased salinity, and D. salina also could rapidly decrease or increase single cell glycerol contents to adapt to hypoosmotic or hyperosmotic shock. The expression level of G3pdh in D. salina grown at various salinities was significantly inversely correlated to the salinity, but there was no significant correlation between the expression level of G3pdh and salinity after 2 h of treatment by hyperosmotic or hypoosmotic shock.

  6. Mapping of depositional and non-depositional areas in Salinas, California streams with concurrent pyrethroid and benthic macroinvertebrate assessments.

    PubMed

    Hall, Lenwood W; Anderson, Ronald D; Killen, William D

    2013-01-01

    This study used sediment mapping to determine the spatial extent of depositional and non-depositional areas in the wetted stream bed of four urban streams in Salinas, California. After the stream mapping was completed, 8 pyrethroids were analytically measured from randomly selected sites in 12 depositional and 12 non-depositional areas in the four Salinas streams. Benthic macroinvertebrate samples were collected and identified from depositional and non-depositional areas where pyrethroids were measured. In addition, physical habitat was also evaluated at each site where benthic communities were collected. Based on a random sampling design, 24 % of the 96 sediment sampling sites in the Salinas streams were classified as predominately depositional areas. Mean total pyrethroid concentrations were approximately 2× to 61× times higher in depositional areas of the Salinas streams when compared to non-depositional areas. Physical habitat scores from the 12 depositional and 12 non-depositional areas in the Salinas stream sites were extremely low compared with other California streams thus demonstrating that impaired physical habitat is a critical stressor in these streams. Approximately 6,300 individual macroinvertebrates were picked and identified from 70 taxa from the 24 Salinas stream sites. The most dominant taxa collected were all considered tolerant of environmental stressors and dominant taxa from both depositional and non-deposition areas were similar. Ten different benthic metrics for the Salinas streams were similar for the depositional areas, where pyrethroid concentrations consistently exceeded laboratory based toxicity thresholds, and non-depositional areas where pyrethroid concentrations were much lower. These results suggest that factors other than pyrethroids are responsible for impacting resident benthic communities in these urban Salinas streams.

  7. Maladaptive Sex Ratio Adjustment in the Invasive Brine Shrimp Artemia franciscana.

    PubMed

    Lievens, Eva J P; Henriques, Gil J B; Michalakis, Yannis; Lenormand, Thomas

    2016-06-01

    Sex allocation theory is often hailed as the most successful area of evolutionary theory due to its striking success as a predictor of empirical observations [1]. Most naturally occurring sex ratios can be explained by the principle of equal investment in the sexes [2-4] or by cases of "extraordinary" sex allocation [5]. Deviations from the expected sex ratio are often correlated with weak selection or low environmental predictability (e.g., [6, 7]); true cases of aberrant sex allocation are surprisingly rare [8]. Here, we present a case of long-lasting maladaptive sex allocation, which we discovered in invasive populations of the exclusively sexual brine shrimp Artemia franciscana. A. franciscana was introduced to Southern France roughly 500 generations ago [9]; since then, it has coexisted with the native asexual species Artemia parthenogenetica [10]. Although we expect A. franciscana to produce balanced offspring sex ratios, we regularly observed extremely male-biased sex ratios in invasive A. franciscana, which were significantly correlated to the proportion of asexuals in the overall population. We experimentally proved that both invasive- and native-range A. franciscana overproduced sons when exposed to excess females, without distinguishing between conspecific and asexual females. We conclude that A. franciscana adjust their offspring sex ratio in function of the adult sex ratio but are information limited in the presence of asexual females. Their facultative adjustment trait, which is presumably adaptive in their native range, has thus become maladaptive in the invasive range where asexuals occur. Despite this, it has persisted unchanged for hundreds of generations. PMID:27185556

  8. Intracellular water in Artemia cysts (brine shrimp): Investigations by deuterium and oxygen-17 nuclear magnetic resonance.

    PubMed

    Kasturi, S R; Seitz, P K; Chang, D C; Hazlewood, C F

    1990-08-01

    The dormant cysts of Artemia undergo cycles of hydration-dehydration without losing viability. Therefore, Artemia cysts serve as an excellent intact cellular system for studying the dynamics of water-protein interactions as a function of hydration. Deuterium spin-lattice (T(1)) and spin-spin (T(2)) relaxation times of water in cysts hydrated with D(2)O have been measured for hydrations between 1.5 and 0.1 g of D(2)O per gram of dry solids. When the relaxation rates (I/T(1), I/T(2)) of (2)H and (17)O are plotted as a function of the reciprocal of hydration (1/H), an abrupt change in slope is observed near 0.6 g of D(2)O (or H(2) (17)O)/gram of dry solids, the hydration at which conventional metabolism is activated in this system. The results have been discussed in terms of the two-site and multisite exchange models for the water-protein interaction as well as protein dynamics models. The (2)H and (17)O relaxation rates as a function of hydration show striking similarities to those observed for anisotropic motion of water molecules in protein crystals.It is suggested here that although the simple two-site exchange model or n-site exchange model could be used to explain our data at high hydration levels, such models are not adequate at low hydration levels (<0.6 g H(2)O/g) where several complex interactions between water and proteins play a predominant role in the relaxation of water nuclei. We further suggest that the abrupt change in the slope of I/T(1) as a function of hydration in the vicinity of 0.6 g H(2)O/g is due to a change in water-protein interactions resulting from a variation in the dynamics of protein motion. PMID:19431762

  9. Identification and characterization of a new strain of the unicellular green alga Dunaliella salina (Teod.) from Korea.

    PubMed

    Polle, Jurgen E W; Struwe, Lena; Jin, Eonseon

    2008-05-01

    The unicellular green alga Dunaliella salina is a halotolerant eukaryotic organism. Its halophytic properties provide an important advantage for open pond mass cultivation, since D. salina can be grown selectively. D. salina was originally described by E. C. Teodoresco in 1905. Since that time, numerous isolates of D. salina have been identified from hypersaline environments on different continents. The new Dunaliella strain used for this study was isolated from the salt farm area of the west coastal side of South Korea. Cells of the new strain were approximately oval- or pear-shaped (approximately 16-24 microm long and 10-15 microm wide), and contained one pyrenoid, cytoplasmatic granules, and no visible eyespot. Although levels of beta-carotene per cell were relatively low in cells grown at salinities between 0.5 to 2.5 M NaCl, cells grown at 4.5 M NaCl contained about a ten-fold increase in cellular levels of beta-carotene, which demonstrated that cells of the new Korean strain of Dunaliella can overaccumulate beta- carotene in response to salt stress. Analysis of the ITS1 and ITS2 regions of the new Korean isolate showed that it is in the same clade as D. salina. Consequently, based on comparative cell morphology, biochemistry, and molecular phylogeny, the new Dunaliella isolate from South Korea was classified as D. salina KCTC10654BP. PMID:18633277

  10. Sediment bioassays with oyster larvae

    SciTech Connect

    Chapman, P.M.; Morgan, J.D.

    1983-10-01

    Tests with naturally-occurring sediments are rare and sediment testing methodology is not standardized. The authors present a simple methodology for undertaking sediment bioassays with oyster larvae, and present data from a recent study to prove the utility of this method.

  11. Effects of salinity and ultraviolet radiation on the bioaccumulation of mycosporine-like amino acids in Artemia from Lake Urmia (Iran).

    PubMed

    Khosravi, Sanaz; Khodabandeh, Saber; Agh, Naser; Bakhtiarian, Mahdieh

    2013-01-01

    We investigated the effects of salinity and artificial UV radiation on the accumulation of mycosporine-like amino acids (MAAs) in sexual and parthenogenetic Artemia from Lake Urmia. The nauplii hatched from the cysts were cultured until adulthood under two salinities (150 and 250 g L(-1) ) and two light treatments (PAR and PAR+UVR) in the laboratory. Finally, the Artemia were analyzed for their concentration of MAAs. In most of the cases, the higher salinity level applied was found to increase the MAA concentrations in both Artemia populations significantly. The acquisition efficiency of MAAs in both Artemia populations increased under exposure to UVR-supplemented photosynthetically active radiation (PAR) compared to those raised under PAR, except for Porphyra-334. It was observed that combination of UV radiation and elevated salinity significantly increased the bioaccumulation of MAAs. Thus, the presence of these compounds in these populations of Artemia may increase their adaptability for living in high-UV and high-salinity conditions prevailing in Lake Urmia. Higher concentrations of MAAs in the parthenogenetic population of Artemia could be probably attributed to its mono sex nature and higher adaptation capacities to extreme environmental conditions. PMID:22998644

  12. How the pilidium larva feeds

    PubMed Central

    2013-01-01

    Introduction The nemertean pilidium is a long-lived feeding larva unique to the life cycle of a single monophyletic group, the Pilidiophora, which is characterized by this innovation. That the pilidium feeds on small planktonic unicells seems clear; how it does so is unknown and not readily inferred, because it shares little morphological similarity with other planktotrophic larvae. Results Using high-speed video of trapped lab-reared pilidia of Micrura alaskensis, we documented a multi-stage feeding mechanism. First, the external ciliation of the pilidium creates a swimming and feeding current which carries suspended prey past the primary ciliated band spanning the posterior margins of the larval body. Next, the larva detects prey that pass within reach, then conducts rapid and coordinated deformations of the larval body to re-direct passing cells and surrounding water into a vestibular space between the lappets, isolated from external currents but not quite inside the larva. Once a prey cell is thus captured, internal ciliary bands arranged within this vestibule prevent prey escape. Finally, captured cells are transported by currents within a buccal funnel toward the stomach entrance. Remarkably, we observed that the prey of choice – various cultured cryptomonads – attempt to escape their fate. Conclusions The feeding mechanism deployed by the pilidium larva coordinates local control of cilia-driven water transport with sensorimotor behavior, in a manner clearly distinct from any other well-studied larval feeding mechanisms. We hypothesize that the pilidium’s feeding strategy may be adapted to counter escape responses such as those deployed by cryptomonads, and speculate that similar needs may underlie convergences among disparate planktotrophic larval forms. PMID:23927417

  13. Use of conditioned medium for efficient transformation and cost-effective cultivation of Nannochloropsis salina.

    PubMed

    Kang, Nam Kyu; Lee, Bongsoo; Shin, Sung-Eun; Jeon, Seungjib; Park, Min S; Yang, Ji-Won

    2015-04-01

    The oleaginous microalga Nannochloropsis sp. has been spotlighted as a promising candidate in genetic engineering research for biodiesel production. However, one of the major bottlenecks in the genetic manipulation against Nannochloropsis sp. is low transformation efficiency. Based on the idea that they grow rapidly in broth culture, the effect of conditioned medium on colonization and transformation efficiency of Nannochloropsis salina was investigated. Cells grown on agar plates with 20-40% conditioned medium produced colonies that were approximately 2.3-fold larger than cells grown without conditioned medium. More importantly, the transformation efficiency was about 2-fold greater on plates with 30% conditioned medium relative to those without conditioned medium. In addition, FAME productivity in liquid cultures with 100% conditioned medium increased up to 20% compared with cultures of control medium. These results suggest that conditioned medium can be applied for efficient transformation and cost-effective cultivation of N. salina for biodiesel production. PMID:25656867

  14. Facile sand enhanced electro-flocculation for cost-efficient harvesting of Dunaliella salina.

    PubMed

    Xiong, Qiong; Pang, Qi; Pan, Xinwei; Chika, A Okonkwo; Wang, Liqing; Shi, Jia; Jia, Lishan; Chen, Changping; Gao, Yahui

    2015-01-01

    Energy consumption and water resource in the cultivation and harvesting steps still need to be minimized for the popularization of the microalgae-based products. An efficient electro-flocculation method for harvesting Dunaliella Salina integrated with local sand has been successfully applied. Sand was effective for speeding up the processes of flocculation and sedimentation of algal flocs and the electrolytic hydroxides was essential to bridge the sand and small flocs into large dense flocs. The maximal recovery effective improved from 95.13% in 6min to 98.09% in 4.5min and the optimal electrical energy consumption decreased 51.03% compared to conventional electro-flocculation in a laboratory ambient condition. Furthermore, reusing the flocculated medium in cultivation of the D. Salina with nitrogen supplemented performed no worse than using fresh medium. This sand enhanced electro-flocculation (SEF) technology provides a great potential for saving time and energy associated with improving microalgae harvesting.

  15. High-pH-induced flocculation-flotation of the hypersaline microalga Dunaliella salina.

    PubMed

    Besson, Alexandre; Guiraud, Pascal

    2013-11-01

    Natural autoflocculation was not observed in a Dunaliella salina hypersaline culture and the microalgae did not float without destabilization of the algal suspension. High-pH-induced flocculation by sodium hydroxide addition was chosen to induce flotation. Recovery efficiencies greater than 90% and concentration factors of around 20 were reached. An autoflocculation mechanism, with precipitation of magnesium hydroxide, is proposed to explain a sweeping flotation of D. salina cells. The influence of the flow rate of sodium hydroxide addition was also studied to anticipate the constraints related to the industrialization of this process. The flow rate of sodium hydroxide addition had no effect on the recovery efficiency and reduced the concentration factor only for abrupt injections. Natural increase of culture pH by photosynthetic activity could reduce the amount of base consumed. Non-harvested cells remained viable during pH increase and could be used as inoculum for a new culture.

  16. Workbook on the Identification of Mosquito Larvae.

    ERIC Educational Resources Information Center

    Pratt, Harry D.; And Others

    This self-instructional booklet is designed to enable public health workers identify larvae of some important North American mosquito species. The morphological features of larvae of the various genera and species are illustrated in a programed booklet, which also contains illustrated taxonomic keys to the larvae of 11 North American genera and to…

  17. [Analysis of the mineral element contents of axenic and natural Dunaliella salina].

    PubMed

    Tang, Ying; Wang, Chang-hai; Huang, Di

    2010-07-01

    The contents of eleven mineral elements, including Mg, Fe, K, Ca, Na, Mn, Zn, Cu, Ni, Cd and Cr contents of axenic and natural Dunaliella salina and their culture supernatants in the different period of exponential phase were determined with flame atomic absorption spectrophotometer(AAS). The results show as follows: (1) The contents of Mg, Fe, K, Ca, and Na are between 1 and 10 mg x g(-1). The contents of Zn, Cu, Mn, and Ni are between 0.1 and 1 mg x g(-1). There are little Cd and Cr in the microalgae. (2) The changes in the content of mineral elements of axenic and natural Dunaliella salina during different phases are almost the same. The contents of Mg, Fe, K, Ca, Na, Mn and Cu decreased along with the growth of the microalgae, especially the content of Ca. The contents of Mg, Fe, K, Ca and Na in the culture supernatants keep stable in the culture process and have no distinct difference among axenic and natural Dunaliella salina. But the contents of Cu and Mn in the culture supernatants increased greatly in the middle and end of exponential phase. (3) The contents of Mg, K, Cu, and Ni show no significant differences in axenic and natural microalgae. The contents of Fe, Ca, Na and Zn in the natural microalgae decreased greatly in the middle of exponential phase and were less than in axenic one, but increased at the end of exponential phase and were higher than in axenic one. These results provide reference for further to applying the resource of Dunaliella salina and studying the relationship of microalgae and associated bacteria in the culture.

  18. Carotenoid and fatty acid metabolism in nitrogen-starved Dunaliella salina, a unicellular green microalga.

    PubMed

    Lamers, Packo P; Janssen, Marcel; De Vos, Ric C H; Bino, Raoul J; Wijffels, René H

    2012-11-30

    Nitrogen availability and light intensity affect β-carotene overproduction in the green alga Dunaliella salina. Following a previous study on high-light stress, we here report on the effect of nitrogen depletion on the growth characteristics and β-carotene as well as fatty acid metabolism of D. salina under a constant light regime in a turbidostat. Upon nitrogen depletion, the biomass yield on absorbed light approximately doubled, due to a transient increase in cell division rate, swelling of the cells and a linear increase of the density of the cells. Simultaneously, β-carotene started to accumulate up to a final intracellular concentration of 14 mg LCV⁻¹ (i.e. 2.7% of AFDW). This β-carotene production accounted for 6% of the increased density of the cells, indicating that other biochemical constituents accumulated as well. Since D. salina accumulates β-carotene in lipid globules, we also determined the fatty acid content and composition of D. salina. The intracellular concentration of the total fatty acid pool did not change significantly during nitrogen starvation, indicating that β-carotene and total fatty acid accumulation were unrelated, similar to what was found previously for high-light treated cells. However, for both high-light and nitrogen stress, β-carotene accumulation negatively correlated with the degree of unsaturation of the total fatty acid pool and, within the individual fatty acids, correlated positively with oleic acid biosynthesis, suggesting that oleic acid may be a key component of the lipid-globule-localized triacylglycerols and thereby in β-carotene accumulation.

  19. Different physiological responses influenced by salinity in genetically related Dunaliella salina isolates.

    PubMed

    Narváez-Zapata, José Alberto; Rojas-Herrera, Rafael; López-Uc, Yamilka; Sánchez-Estudillo, Leticia

    2011-05-01

    An isolate of Dunaliella salina (DUNS-1) and other two isolates (DUNS-2 and DUNS-3), collected from coastal lagoons with 14 and 30% (w/v) of NaCl, respectively, were analyzed under different saline conditions. Glycerol (380 mg l(-1)) and carotene (5.9 mg l(-1)) contents for DUNS-2 were 0.3 and 10 times higher than DUNS-3, even though both isolates were collected from the same lagoon and share a similar ribosomal DNA sequence.

  20. Ultrastructure and molecular phylogeny of thaumatomonads (Cercozoa) with emphasis on Thaumatomastix salina from Oslofjorden, Norway.

    PubMed

    Ota, Shuhei; Eikrem, Wenche; Edvardsen, Bente

    2012-07-01

    A culture of Thaumatomastix was isolated from a sediment sample collected in Oslofjorden and established as a monospecific strain (UIO286). Based on this culture, light and transmission electron microscopy and phylogenetic analyses were carried out. Thaumatomastix species are confined within the order Thaumatomonadida of the class Imbricatea and phylum Cercozoa. They are heterotrophic and their cell bodies are covered with silica scales. Observations of thin sections as well as whole mounts indicate that the morphology and ultrastructure of UIO286 is identical to T. salina, which was initially described from salt pools in Denmark. Detailed examination revealed some new features such as the presence of pseudopodia and silica deposition vesicles producing spine scales. The phylogeny presented here includes ribosomal DNA sequences from both imbricatean cultures and environmental samples. The 18S rDNA phylogenetic tree suggests that (i) Thaumatomastix is paraphyletic within the Thaumatomonadida clade, (ii) there is no close affinity between T. salina and other cultured and sequenced strains, but it is closely related to a sequence obtained from environmental DNA; we propose the present strain to serve as a reference culture of Thaumatomastix species and T. salina. Further, we discuss the distribution, habitats, and evolution of scale formation among euglyphids and thaumatomonads. PMID:22177453

  1. View of the Salinas River Valley area south of Monterey Bay, California

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A vertical view of the Salinas River Valley area south of Monterey Bay, California area is seen in this Skylab 3 Earth Resources Experiments Package S190-B (five-inch earth terrain camera) photograph taken from the Skylab space station in Earth orbit. The valley is an irrigated agricultural area, as indicated by the dark-green and light-gray rectangular patterns in the center of the picture. The city of Salinas is barely visible under the cloud cover at the top (north) end of the valley. The dark mass on the left (west) side of the valley is the Santa Lucia mountain range. The Big Sur area is on the left and partly covered by clouds. The Diablo Range forms the dark mass in the lower right (southeast) corner of the photograph. The town of Hillister is the grey area in the dark-green rectangular farm tracts which occupy the floor of the San Benito Valley in the upper right (northeast) corner of the photograph. The Salinas River flows northwestward toward Monterey Bay. The towns of Soleda

  2. Hydrothermal liquefaction of Spirulina and Nannochloropsis salina under subcritical and supercritical water conditions.

    PubMed

    Toor, Saqib S; Reddy, Harvind; Deng, Shuguang; Hoffmann, Jessica; Spangsmark, Dorte; Madsen, Linda B; Holm-Nielsen, Jens Bo; Rosendahl, Lasse A

    2013-03-01

    Six hydrothermal liquefaction experiments on Nannochloropsis salina and Spirulina platensis at subcritical and supercritical water conditions (220–375 °C, 20–255 bar) were carried out to explore the feasibility of extracting lipids from wet algae, preserving nutrients in lipid-extracted algae solid residue, and recycling process water for algae cultivation. GC–MS, elemental analyzer, FT-IR, calorimeter and nutrient analysis were used to analyze bio-crude, lipid-extracted algae and water samples produced in the hydrothermal liquefaction process. The highest bio-crude yield of 46% was obtained on N. salina at 350 °C and 175 bar. For S. platensis algae sample, the optimal hydrothermal liquefaction condition appears to be at 310 °C and 115 bar, while the optimal condition for N. salina is at 350 °C and 175 bar. Preliminary data also indicate that a lipid-extracted algae solid residue sample obtained in the hydrothermal liquefaction process contains a high level of proteins.

  3. Molecular cloning and functional characterization of MnSOD from Dunaliella salina.

    PubMed

    Zhang, Shu; Li, Xin Ran; Xu, Hui; Cao, Yu; Ma, Shu Han; Cao, Yi; Qiao, Dairong

    2014-05-01

    Dunaliella salina, a unicellular green alga, has the potential to grow in hypersaline environments via one of its gene products, superoxide dismutase (SOD). The superoxide radicals (O2 (-) ) produced by environmental stresses can cause damage to cells, and SOD catalyzes the turnover of such free radicals to protect cells. In this study, the gene coding for SOD in D. salina was cloned and the product was further identified and characterized. The open reading frame of this gene was 651 bp long, encoding for 217 amino acids. According to the sequence alignment using BLAST, native polyacrylamide electrophoresis for SOD activity analysis, and atomic absorption spectroscopy analysis, this protein belongs to the manganese-containing superoxide dismutase (MnSOD) family. Complementation analysis, performed by introducing plasmids carrying an inducible version of the D. salina gene encoding for MnSOD into an SOD-deficient mutant of E.coli, revealed that this gene could not only complement the defects in SOD activity, but was also capable of providing a stronger tolerance to restrictive growth conditions, such as high salt and prolonged UV exposure, compared to the tolerance of wild-type strains.

  4. Bio-oil from hydro-liquefaction of Dunaliella salina over Ni/REHY catalyst.

    PubMed

    Yang, Chao; Jia, Lishan; Chen, Changping; Liu, Guangfa; Fang, Weiping

    2011-03-01

    The hydro-liquefaction of Dunaliella salina over solid acid catalyst was examined under moderate conditions (200°C, 2.0 MPa, 60 min). The significant increment of bio-oil yield was obtained over Ni/REHY catalyst, increasing about 20% compared without modified REHY. H(2)-temperature-programmed desorption (H(2)-TPD) and X-ray powder diffraction (XRD) demonstrated that Ni/REHY as bifunctional catalyst played roles in hydrogenation and cracking, and further achieved the deoxygenation and desulfurization of D. salina under hydrogen gas. The oxygen and sulfur contents of bio-oils decreased relative to D. salina, and the higher heating value (HHV) significantly increased to 30.11 MJ/kg. From gas chromatography/mass spectrometry (GC/MS), the dominant compounds of the bio-oils were found to be esters, glycerins. The qualities of bio-oils were greatly improved. Hydro-liquefaction was beneficial to the exploration of bio-oils from microalgae.

  5. OPTIMIZATION OF SALT CONCENTRATIONS FOR A HIGHER CAROTENOID PRODUCTION IN DUNALIELLA SALINA (CHLOROPHYCEAE)(1).

    PubMed

    Farhat, Nèjia; Rabhi, Mokded; Falleh, Hanen; Jouini, Jihène; Abdelly, Chedly; Smaoui, Abderrazak

    2011-10-01

    Dunaliella salina (Dunal) Teodor, when treated over 25 d with a wide range of NaCl salinities (0.6-4.5 M), showed its maximal growth potentialities at 1.5-3.0 M NaCl and was able to survive even at 4.5 M NaCl. Sodium concentrations increased significantly at the supraoptimal salinities, reaching up to 5 mmol · g(-1) dry weight (dwt) at 4.5 M NaCl. Interestingly, ability of D. salina to take up essential mineral nutrients was not impaired by increased salinity. As for growth, chl concentrations were maximal in the 1.5-3.0 M NaCl range. Interestingly, carotenoid concentrations increased with the increasing salinity. The highest values of total antioxidant activity (5.2-6.9 mg gallic acid equivalents [GAE] · g(-1) dwt), antiradical activity, and reducing power were measured at 1.5-3.0 M NaCl. As a whole, these results showed that at 1.5-3.0 M NaCl, D. salina produce appreciable antioxidant level. But, once it reaches its growth maximum, a salt addition up to 4.5 M could enhance its carotenoid yield.

  6. Toxic effects of chemical pesticides (trichlorfon and dimehypo) on Dunaliella salina.

    PubMed

    Chen, Hui; Jiang, Jian-Guo

    2011-07-01

    Dunaliella salina, a unicellular green alga of environmental tolerance, was employed as test organism to investigate the toxicity effects of trichlorfon and dimehypo widely used in agriculture and veterinary as pesticides. The influences of trichlorfon and dimehypo on cell growth, β-carotene level, cell morphology changes, and activities of superoxide dismutase (Sod) and catalase (Cat) were investigated. At the concentrations less than 0.050 g L(-1) trichlorfon or 0.0005 g L(-1) dimehypo, cell responses were similar to control. When treated with 0.075-0.100 g L(-1) trichlorfon or 0.001-0.004 g L(-1) dimehypo, cell growth and β-carotene levels declined at first and then revived. When concentrations were higher than 0.125 g L(-1) trichlorfon or 0.005 g L(-1) dimehypo, both cell growth and β-carotene levels decreased until they were undetectable. The 10-d IC50 of trichlorfon and dimehypo on D. salina were 0.179 g L(-1) and 0.032 g L(-1). Both pollutants could stimulate the increase of Cat activity at a low concentration. Tolerance of D. salina to trichlorfon was obviously higher than that of dimehypo.

  7. Cloning and characterization of a phosphate transporter gene in Dunaliella salina.

    PubMed

    Li, Shao-He; Xia, Bing-Bing; Zhang, Chi; Cao, Jiao; Bai, Lin-Han

    2012-08-01

    The full-length cDNA of a Na(+) -dependent Pi transport gene (DsSPT1) in Dunaliella salina was cloned by 3' and 5' Rapid Amplification of cDNA Ends (RACE), with an open reading frame (ORF) encoding 716 predicted amino acids, which exhibited 60.5% identity to that of Na(+) -dependent Pi transport 1 (DvSPT1) from Dunaliella viridis. Hydrophobicity and secondary structure prediction revealed 11 conserved transmembrane domains similar to those found in DvSPT1 from D. viridis and PHO89 from Saccharomyces cerevisiae. The result of real-time quantitative PCR showed that expression level of DsSPT1 was enhanced at first and reached its peak at 90 min after salt stress; however, D. salina cells rapidly absorbed extracellular inorganic phosphorus which was determined by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) during the first 5 min under salt stress. It suggested that D. salina on the absorption of inorganic phosphorus was regulated at DsSPTI posttranslational level.

  8. In Vivo NMR Metabolic Profiling of Fabrea salina Reveals Sequential Defense Mechanisms against Ultraviolet Radiation

    PubMed Central

    Marangoni, Roberto; Paris, Debora; Melck, Dominique; Fulgentini, Lorenzo; Colombetti, Giuliano; Motta, Andrea

    2011-01-01

    Fabrea salina is a hypersaline ciliate that is known to be among the strongest ultraviolet (UV)-resistant microorganisms; however, the molecular mechanisms of this resistance are almost unknown. By means of in vivo NMR spectroscopy, we determined the metabolic profile of living F. salina cells exposed to visible light and to polychromatic UV-B + UV-A + Vis radiation for several different exposure times. We used unsupervised pattern-recognition analysis to compare these profiles and discovered some metabolites whose concentration changed specifically upon UV exposure and in a dose-dependent manner. This variation was interpreted in terms of a two-phase cell reaction involving at least two different pathways: an early response consisting of degradation processes, followed by a late response activating osmoprotection mechanisms. The first step alters the concentration of formate, acetate, and saturated fatty-acid metabolites, whereas the osmoprotection modifies the activity of betaine moieties and other functionally related metabolites. In the latter pathway, alanine, proline, and sugars suggest a possible incipient protein synthesis as defense and/or degeneration mechanisms. We conclude that NMR spectroscopy on in vivo cells is an optimal approach for investigating the effect of UV-induced stress on the whole metabolome of F. salina because it minimizes the invasiveness of the measurement. PMID:21190674

  9. Results on Artemia cysts, lettuce and tobacco seeds in the biobloc 4 experiment flown aboard the Soviet biosatellite Cosmos 1129

    NASA Astrophysics Data System (ADS)

    Gaubin, Y.; Planel, H.; Gasset, G.; Pianezzi, B.; Delpoux, M.; Clegg, J.; Kovalev, E. E.; Nevzgodina, L. V.; Maximova, E. N.; Miller, A. T.

    Artemia cysts, lettuce and tobacco seeds were flown aboard the Cosmos 1129 for 19 days. A correlative method was used in order to determine the passage of cosmic heavy ions (HZE particles) through the biological test objects. This space flight resulted in a decrease on hatchability, nucleic acid and protein synthesis in hydrated Artemia cysts. HZE particle effects on plant cellular chromosomes are confirmed. In tobacco seeds, a stimulating effect on germination rate and a higher frequency of abnormalities were observed. Dormant biological objects are a very suitable material to study cosmic ray effects: these objects can be arranged in monolayers and sandwiched between visual track detectors in order to determine the passage of the cosmic heavy ions (HZE particles). On the other hand this method allows us to study effects of microgravity and those of the protonic component of cosmic rays in the objects not hit by the HZE particles.

  10. Results on artemia cysts, lettuce and tobacco seeds in the Biobloc 4 experiment flown aboard the Soviet biosatellite Cosmos 1129

    SciTech Connect

    Gaubin, Y.; Planel, H.; Gasset, G.; Pianezzi, B.

    1983-01-01

    The effects of space flight factors, in particular the heavy ion component of cosmic rays, on dormant stages of life forms were investigated as part of the Biobloc 4 experiment flown aboard the Cosmos 1129 biosatellite. Artemia cysts and seeds of tobacco and lettuce plants were placed in tubes and in monolayers sandwiched between layers of visual particle track detectors. Although Artemia cysts exposed in the dry state did not differ from ground controls, hydrated cysts exhibited a slight decrease in hatchability and reduced (C-14)O2 incorporation and protein and nucleic acid synthesis. For cysts held in the monolayers, hits by HZE particles were observed to stimulate emergence, hatching and survival. Higher proportions of chromosomal aberrations were found in lettuce seeds hit by HZE particles, while space flight produced a stimulatory effect on both germination rate and abnormality frequency in both hit and nonhit tobacco seeds. 9 references.

  11. Study of model systems to test the potential function of Artemia group 1 late embryogenesis abundant (LEA) proteins.

    PubMed

    Warner, Alden H; Guo, Zhi-hao; Moshi, Sandra; Hudson, John W; Kozarova, Anna

    2016-01-01

    Embryos of the brine shrimp, Artemia franciscana, are genetically programmed to develop either ovoviparously or oviparously depending on environmental conditions. Shortly upon their release from the female, oviparous embryos enter diapause during which time they undergo major metabolic rate depression while simultaneously synthesize proteins that permit them to tolerate a wide range of stressful environmental events including prolonged periods of desiccation, freezing, and anoxia. Among the known stress-related proteins that accumulate in embryos entering diapause are the late embryogenesis abundant (LEA) proteins. This large group of intrinsically disordered proteins has been proposed to act as molecular shields or chaperones of macromolecules which are otherwise intolerant to harsh conditions associated with diapause. In this research, we used two model systems to study the potential function of the group 1 LEA proteins from Artemia. Expression of the Artemia group 1 gene (AfrLEA-1) in Escherichia coli inhibited growth in proportion to the number of 20-mer amino acid motifs expressed. As well, clones of E. coli, transformed with the AfrLEA-1 gene, expressed multiple bands of LEA proteins, either intrinsically or upon induction with isopropyl-β-thiogalactoside (IPTG), in a vector-specific manner. Expression of AfrLEA-1 in E. coli did not overcome the inhibitory effects of high concentrations of NaCl and KCl but modulated growth inhibition resulting from high concentrations of sorbitol in the growth medium. In contrast, expression of the AfrLEA-1 gene in Saccharomyces cerevisiae did not alter the growth kinetics or permit yeast to tolerate high concentrations of NaCl, KCl, or sorbitol. However, expression of AfrLEA-1 in yeast improved its tolerance to drying (desiccation) and freezing. Under our experimental conditions, both E. coli and S. cerevisiae appear to be potentially suitable hosts to study the function of Artemia group 1 LEA proteins under environmentally

  12. Multiple {gamma}-glutamylation: A novel type of post-translational modification in a diapausing Artemia cyst protein

    SciTech Connect

    Hasegawa, Mai; Ikeda, Yuka; Kanzawa, Hideaki; Sakamoto, Mika; Goto, Mina; Tsunasawa, Susumu; Uchiumi, Toshio; Odani, Shoji

    2010-03-26

    A highly hydrophilic, glutamate-rich protein was identified in the aqueous phenol extract from the cytosolic fraction of brine shrimp (Artemia franciscana) diapausing cysts and termed Artemia phenol soluble protein (PSP). Mass spectrometric analysis revealed the presence of many protein peaks around m/z 11,000, separated by 129 atomic mass units; this value corresponds to that of glutamate, which is strongly suggestive of heterogeneous polyglutamylation. Polyglutamylation has long been known as the functionally important post-translational modification of tubulins, which carry poly(L-glutamic acid) chains of heterogeneous length branching off from the main chain at the {gamma}-carboxy groups of a few specific glutamate residues. In Artemia PSP, however, Edman degradation of enzymatic peptides revealed that at least 13, and presumably 16, glutamate residues were modified by the attachment of a single L-glutamate, representing a hitherto undescribed type of post-translational modification: namely, multiple {gamma}-glutamylation or the addition of a large number of glutamate residues along the polypeptide chain. Although biological significance of PSP and its modification is yet to be established, suppression of in vitro thermal aggregation of lactate dehydrogenase by glutamylated PSP was observed.

  13. Salt sensitivity of the morphometry of Artemia franciscana during development: a demonstration of 3D critical windows.

    PubMed

    Mueller, Casey A; Willis, Eric; Burggren, Warren W

    2016-02-01

    A 3D conceptual framework of 'critical windows' was used to examine whether the morphometry of Artemia franciscana is altered by salinity exposure during certain key periods of development. Artemia franciscana were hatched at 20 ppt (designated control salinity) and were then exposed to 10, 30, 40 or 50 ppt either chronically (days 1-15) or only on days 1-6, 7-9, 10-12 or 13-15. On day 15, maturity was assessed and morphometric characteristics, including mass, total body length, tail length and width, length of the third swimming appendage and eye diameter, were measured. Maturation and morphometry on day 15 were influenced by the exposure window and salinity dose. Artemia franciscana were generally larger following exposure to 10 and 40 ppt during days 1-6 and 7-9 when compared with days 10-12 and 13-15, in part due to a higher percentage of mature individuals. Exposure to different salinities on days 1-6 produced the greatest differences in morphometry, and thus this appears to be a period in development when A. franciscana is particularly sensitive to salinity. Viewing the developmental window as three-dimensional allowed more effective visualization of the complex interactions between exposure window, stressor dose and the magnitude of morphometric changes in A. franciscana.

  14. Salt sensitivity of the morphometry of Artemia franciscana during development: a demonstration of 3D critical windows.

    PubMed

    Mueller, Casey A; Willis, Eric; Burggren, Warren W

    2016-02-01

    A 3D conceptual framework of 'critical windows' was used to examine whether the morphometry of Artemia franciscana is altered by salinity exposure during certain key periods of development. Artemia franciscana were hatched at 20 ppt (designated control salinity) and were then exposed to 10, 30, 40 or 50 ppt either chronically (days 1-15) or only on days 1-6, 7-9, 10-12 or 13-15. On day 15, maturity was assessed and morphometric characteristics, including mass, total body length, tail length and width, length of the third swimming appendage and eye diameter, were measured. Maturation and morphometry on day 15 were influenced by the exposure window and salinity dose. Artemia franciscana were generally larger following exposure to 10 and 40 ppt during days 1-6 and 7-9 when compared with days 10-12 and 13-15, in part due to a higher percentage of mature individuals. Exposure to different salinities on days 1-6 produced the greatest differences in morphometry, and thus this appears to be a period in development when A. franciscana is particularly sensitive to salinity. Viewing the developmental window as three-dimensional allowed more effective visualization of the complex interactions between exposure window, stressor dose and the magnitude of morphometric changes in A. franciscana. PMID:26685168

  15. Phenotypic and genetic characterization of Dunaliella (Chlorophyta) from Indian salinas and their diversity

    PubMed Central

    2012-01-01

    Background The genus Dunaliella (Class – Chlorophyceae) is widely studied for its tolerance to extreme habitat conditions, physiological aspects and many biotechnological applications, such as a source of carotenoids and many other bioactive compounds. Biochemical and molecular characterization is very much essential to fully explore the properties and possibilities of the new isolates of Dunaliella. In India, hyper saline lakes and salt pans were reported to bloom with Dunaliella spp. However, except for the economically important D. salina, other species are rarely characterized taxonomically from India. Present study was conducted to describe Dunaliella strains from Indian salinas using a combined morphological, physiological and molecular approach with an aim to have a better understanding on the taxonomy and diversity of this genus from India. Results Comparative phenotypic and genetic studies revealed high level of diversity within the Indian Dunaliella isolates. Species level identification using morphological characteristics clearly delineated two strains of D. salina with considerable β-carotene content (>20 pg/cell). The variation in 18S rRNA gene size, amplified with MA1-MA2 primers, ranged between ~1800 and ~2650 base pairs, and together with the phylogeny based on ITS gene sequence provided a pattern, forming five different groups within Indian Dunaliella isolates. Superficial congruency was observed between ITS and rbcL gene phylogenetic trees with consistent formation of major clades separating Indian isolates into two distinct clusters, one with D. salina and allied strains, and another one with D. viridis and allied strains. Further in both the trees, few isolates showed high level of genetic divergence than reported previously for Dunaliella spp. This indicates the scope of more numbers of clearly defined/unidentified species/sub-species within Indian Dunaliella isolates. Conclusion Present work illustrates Indian Dunaliella strains

  16. How the pilidium larva grows

    PubMed Central

    2014-01-01

    Background For animal cells, ciliation and mitosis appear to be mutually exclusive. While uniciliated cells can resorb their cilium to undergo mitosis, multiciliated cells apparently can never divide again. Nevertheless, many multiciliated epithelia in animals must grow or undergo renewal. The larval epidermis in a number of marine invertebrate larvae, such as those of annelids, mollusks and nemerteans, consists wholly or in part of multiciliated epithelial cells, generally organized into a swimming and feeding apparatus. Many of these larvae must grow substantially to reach metamorphosis. Do individual epithelial cells simply expand to accommodate an increase in body size, or are there dividing cells amongst them? If some cells divide, where are they located? Results We show that the nemertean pilidium larva, which is almost entirely composed of multiciliated cells, retains pockets of proliferative cells in certain regions of the body. Most of these are found near the larval ciliated band in the recesses between the larval lobes and lappets, which we refer to as axils. Cells in the axils contribute both to the growing larval body and to the imaginal discs that form the juvenile worm inside the pilidium. Conclusions Our findings not only explain how the almost-entirely multiciliated pilidium can grow, but also demonstrate direct coupling of larval and juvenile growth in a maximally-indirect life history. PMID:24690541

  17. Comparative analysis on the key enzymes of the glycerol cycle metabolic pathway in Dunaliella salina under osmotic stresses.

    PubMed

    Chen, Hui; Lu, Yan; Jiang, Jian-Guo

    2012-01-01

    The glycerol metabolic pathway is a special cycle way; glycerol-3-phosphate dehydrogenase (G3pdh), glycerol-3-phosphate phosphatase (G3pp), dihydroxyacetone reductase (Dhar), and dihydroxyacetone kinase (Dhak) are the key enzymes around the pathway. Glycerol is an important osmolyte for Dunaliella salina to resist osmotic stress. In this study, comparative activities of the four enzymes in D. salina and their activity changes under various salt stresses were investigated, from which glycerol metabolic flow direction in the glycerol metabolic pathway was estimated. Results showed that the salinity changes had different effects on the enzymes activities. NaCl could stimulate the activities of all the four enzymes in various degrees when D. salina was grown under continuous salt stress. When treated by hyperosmotic or hypoosmotic shock, only the activity of G3pdh in D. salina was significantly stimulated. It was speculated that, under osmotic stresses, the emergency response of the cycle pathway in D. salina was driven by G3pdh via its response to the osmotic stress. Subsequently, with the changes of salinity, other three enzymes started to respond to osmotic stress. Dhar played a role of balancing the cycle metabolic pathway by its forward and backward reactions. Through synergy, the four enzymes worked together for the effective flow of the cycle metabolic pathways to maintain the glycerol requirements of cells in order to adapt to osmotic stress environments.

  18. Environmental heat stress induces epigenetic transgenerational inheritance of robustness in parthenogenetic Artemia model.

    PubMed

    Norouzitallab, Parisa; Baruah, Kartik; Vandegehuchte, Michiel; Van Stappen, Gilbert; Catania, Francesco; Vanden Bussche, Julie; Vanhaecke, Lynn; Sorgeloos, Patrick; Bossier, Peter

    2014-08-01

    The notion that phenotypic traits emerging from environmental experiences are heritable remains under debate. However, the recent report of nonmendelian transgenerational epigenetic inheritance, i.e., the inheritance of traits not determined by the DNA sequence, might make such a phenomenon plausible. In our study, by carrying out common garden experiments, we could provide clear evidences that, on exposure to nonlethal heat shocks, a parental population of parthenogenetic (all female) Artemia (originating from one single female) experiences an increase in levels of Hsp70 production, tolerance toward lethal heat stress, and resistance against pathogenic Vibrio campbellii. Interestingly, these acquired phenotypic traits were transmitted to three successive generations, none of which were exposed to the parental stressor. This transgenerational inheritance of the acquired traits was associated with altered levels of global DNA methylation and acetylated histones H3 and H4 in the heat-shocked group compared to the control group, where both the parental and successive generations were reared at standard temperature. These results indicated that epigenetic mechanisms, such as global DNA methylation and histones H3 and H4 acetylation, have particular dynamics that are crucial in the heritability of the acquired adaptive phenotypic traits across generations.

  19. Experimental taphonomy of Artemia reveals the role of endogenous microbes in mediating decay and fossilization.

    PubMed

    Butler, Aodhán D; Cunningham, John A; Budd, Graham E; Donoghue, Philip C J

    2015-06-01

    Exceptionally preserved fossils provide major insights into the evolutionary history of life. Microbial activity is thought to play a pivotal role in both the decay of organisms and the preservation of soft tissue in the fossil record, though this has been the subject of very little experimental investigation. To remedy this, we undertook an experimental study of the decay of the brine shrimp Artemia, examining the roles of autolysis, microbial activity, oxygen diffusion and reducing conditions. Our findings indicate that endogenous gut bacteria are the main factor controlling decay. Following gut wall rupture, but prior to cuticle failure, gut-derived microbes spread into the body cavity, consuming tissues and forming biofilms capable of mediating authigenic mineralization, that pseudomorph tissues and structures such as limbs and the haemocoel. These observations explain patterns observed in exceptionally preserved fossil arthropods. For example, guts are preserved relatively frequently, while preservation of other internal anatomy is rare. They also suggest that gut-derived microbes play a key role in the preservation of internal anatomy and that differential preservation between exceptional deposits might be because of factors that control autolysis and microbial activity. The findings also suggest that the evolution of a through gut and its bacterial microflora increased the potential for exceptional fossil preservation in bilaterians, providing one explanation for the extreme rarity of internal preservation in those animals that lack a through gut. PMID:25972468

  20. Segmental mismatch in crustacean appendages: the naupliar antennal exopod of Artemia (Crustacea, Branchiopoda, Anostraca).

    PubMed

    Maruzzo, Diego; Minelli, Alessandro; Fusco, Giuseppe

    2009-03-01

    Based on traditional techniques and confocal laser scanning microscopy for external morphology, and immunohistochemistry for the muscular system, we describe here the segmental features of the antennal exopod of Artemia nauplii. Two kinds of serial elements are present, i.e. setae (with cuticular folds at their base) and ringlets (serially arranged sclerites separated by joint-like cuticular folds not extending to form complete rings around the appendage). The two series are usually not in register. The cuticular folds of the setae and of the ringlets are also sites of intermediate insertions of the three exopod muscles: as the two tegumentary structures are discordant in periodicity, this is also mirrored in the pattern of muscle insertions on the two sides of the appendage. Similar cases of segmental mismatch are known for the trunk of several arthropods, but segmental mismatch along the appendages has received very little attention. The occurrence of segmental mismatch in the naupliar appendages of both extant and fossil crustaceans is reviewed and it is suggested here to be a primitive feature of the exopods of both second antennae and mandibles. Problems in the interpretation of morphological evidence are discussed, also in relation to development and evolution of segmentation of naupliar appendages.

  1. Vibrio hispanicus sp. nov., isolated from Artemia sp. and sea water in Spain.

    PubMed

    Gomez-Gil, B; Thompson, F L; Thompson, C C; Garcia-Gasca, A; Roque, A; Swings, J

    2004-01-01

    Three Gram-negative, small, motile, rod-shaped bacteria were isolated from Artemia sp. and sea water in Barcelona, Spain, during 1990 and 1991. They were fermentative, oxidase-positive, sensitive to vibriostatic agent O/129, arginine dihydrolase-positive, lysine and ornithine decarboxylase-negative and grew in the absence of NaCl. They differed from phenotypically related species by their ability to grow at 4 degrees C and utilize L-rhamnose. Cloning of the 16S rRNA gene of the type strain produced two different 16S rRNA gene sequences, which differed by 15 bases (0.99%); comparison of these sequences with those deposited in GenBank showed close relationships with Vibrio proteolyticus (97.6% similarity), Vibrio diazotrophicus (97.9%), Vibrio campbellii (96.8%) and Vibrio alginolyticus (96.8%), among others. DNA-DNA hybridization levels with the closest phylogenetically related Vibrio species were <26.4%. Sufficient evidence is provided to support the identity of the three strains analysed as members of a novel species of the genus Vibrio, for which the name Vibrio hispanicus sp. nov. is proposed, with the type strain LMG 13240T (=CAIM 525T=VIB 213T).

  2. Experimental taphonomy of Artemia reveals the role of endogenous microbes in mediating decay and fossilization.

    PubMed

    Butler, Aodhán D; Cunningham, John A; Budd, Graham E; Donoghue, Philip C J

    2015-06-01

    Exceptionally preserved fossils provide major insights into the evolutionary history of life. Microbial activity is thought to play a pivotal role in both the decay of organisms and the preservation of soft tissue in the fossil record, though this has been the subject of very little experimental investigation. To remedy this, we undertook an experimental study of the decay of the brine shrimp Artemia, examining the roles of autolysis, microbial activity, oxygen diffusion and reducing conditions. Our findings indicate that endogenous gut bacteria are the main factor controlling decay. Following gut wall rupture, but prior to cuticle failure, gut-derived microbes spread into the body cavity, consuming tissues and forming biofilms capable of mediating authigenic mineralization, that pseudomorph tissues and structures such as limbs and the haemocoel. These observations explain patterns observed in exceptionally preserved fossil arthropods. For example, guts are preserved relatively frequently, while preservation of other internal anatomy is rare. They also suggest that gut-derived microbes play a key role in the preservation of internal anatomy and that differential preservation between exceptional deposits might be because of factors that control autolysis and microbial activity. The findings also suggest that the evolution of a through gut and its bacterial microflora increased the potential for exceptional fossil preservation in bilaterians, providing one explanation for the extreme rarity of internal preservation in those animals that lack a through gut.

  3. Experimental taphonomy of Artemia reveals the role of endogenous microbes in mediating decay and fossilization

    PubMed Central

    Butler, Aodhán D.; Cunningham, John A.; Budd, Graham E.; Donoghue, Philip C. J.

    2015-01-01

    Exceptionally preserved fossils provide major insights into the evolutionary history of life. Microbial activity is thought to play a pivotal role in both the decay of organisms and the preservation of soft tissue in the fossil record, though this has been the subject of very little experimental investigation. To remedy this, we undertook an experimental study of the decay of the brine shrimp Artemia, examining the roles of autolysis, microbial activity, oxygen diffusion and reducing conditions. Our findings indicate that endogenous gut bacteria are the main factor controlling decay. Following gut wall rupture, but prior to cuticle failure, gut-derived microbes spread into the body cavity, consuming tissues and forming biofilms capable of mediating authigenic mineralization, that pseudomorph tissues and structures such as limbs and the haemocoel. These observations explain patterns observed in exceptionally preserved fossil arthropods. For example, guts are preserved relatively frequently, while preservation of other internal anatomy is rare. They also suggest that gut-derived microbes play a key role in the preservation of internal anatomy and that differential preservation between exceptional deposits might be because of factors that control autolysis and microbial activity. The findings also suggest that the evolution of a through gut and its bacterial microflora increased the potential for exceptional fossil preservation in bilaterians, providing one explanation for the extreme rarity of internal preservation in those animals that lack a through gut. PMID:25972468

  4. Molecular approaches for improving desiccation tolerance: Insights from the brine shrimp Artemia franciscana

    PubMed Central

    Hand, Steven C.; Menze, Michael A.

    2015-01-01

    Organisms inhabiting both aquatic and terrestrial ecosystems frequently are confronted with the problem of water loss for multiple reasons – exposure to hypersalinity, evaporative water loss, and restriction of intracellular water due to freezing of extracellular fluids. Seasonal desiccation can become severe and lead to the production of tolerant propagules and entry into the state of anhydrobiosis at various stages of the life cycle. Such is the case for gastrula-stage embryos of the brine shrimp, Artemia franciscana. Physiological and biochemical responses to desiccation are central for survival and are multifaceted. This review will evaluate the impact of multiple Late Embryogenesis Abundant (LEA) proteins originating from A. franciscana, together with the non-reducing sugar trehalose, on prevention of desiccation damage at multiple levels of biological organization. Survivorship of desiccation-sensitive cells during water stress can be improved by use of the above protective agents, coupled to metabolic preconditioning and rapid cell drying. However, obtaining long-term stability of cells in the dried state at room temperature has not been accomplished and will require continued efforts on both the physicochemical and biological fronts. PMID:25809151

  5. Impacts of harvesting on brine shrimp (Artemia franciscana) in Great Salt Lake, Utah, USA.

    PubMed

    Sura, Shayna A; Belovsky, Gary E

    2016-03-01

    Selective harvesting can cause evolutionary responses in populations via shifts in phenotypic characteristics, especially those affecting life history. Brine shrimp (Artemia franciscana) cysts in Great Salt Lake (GSL), Utah, USA are commercially harvested with techniques that select against floating cysts. This selective pressure could cause evolutionary changes over time. Our objectives are to (1) determine if there is a genetic basis to cyst buoyancy, (2) determine if cyst buoyancy and nauplii mortality have changed over time, and (3) to examine GSL environmental conditions over time to distinguish whether selective harvesting pressure or a trend in environmental conditions caused changes in cyst buoyancy and nauplii mortality. Mating crosses between floating and sinking parental phenotypes with two food concentrations (low and high) indicated there is a genetic basis to cyst buoyancy. Using cysts harvested from 1991-2011, we found cyst buoyancy decreased and nauplii mortality increased over time. Data on water temperature, salinity, and chlorophyll a concentration in GSL from 1994 to 2011 indicated that although water temperature has increased over time and chlorophyll a concentration has decreased over time, the selective harvesting pressure against floating cysts is a better predictor of changes in cyst buoyancy and nauplii mortality over time than trends in environmental conditions. Harvesting of GSL A. franciscana cysts is causing evolutionary changes, which has implications for the sustainable management and harvesting of these cysts. Monitoring phenotypic characteristics and life-history traits of the population should be implemented and appropriate responses taken to reduce the impacts of the selective harvesting. PMID:27209783

  6. The size and conformation of Artemia (brine-shrimp) ribosomal RNA free in solution.

    PubMed Central

    Donceel, K; Nieuwenhuysen, P; Clauwaert, J

    1982-01-01

    The RNA was isolated from the large ribosomal subunits of the brine shrimp Artemia, and its conformation free in solution was studied by determining its sedimentation and diffusion coefficients. A comparison was made of the hydrodynamic radius of the ribosomal subunit and its isolated RNA in various buffers. The conformation of the rRNA free in solution is more extended than when it is incorporated in the ribosome. This is not only the case when the rRNA solution lacks bivalent and polyvalent cations, but even in the presence of Mg2+ and spermidine, which cause a tightening of RNA. Thus the ribosomal proteins should induce a further tightening of the rRNA during the assembly of the ribosome. In the discussion, the reported data on Escherichia coli rRNA species are presented in such a way that large discrepancies between various studied are revealed, and that they can be compared with the data reported here on the larger rRNA of an eukaryote. PMID:7150228

  7. A century of plant virus management in the Salinas valley of California, 'East of Eden'.

    PubMed

    Wisler, G C; Duffus, J E

    2000-11-01

    The mild climate of the Salinas Valley, CA lends itself well to a diverse agricultural industry. However, the diversity of weeds, crops and insect and fungal vectors also provide favorable conditions for plant virus disease development. This paper considers the incidence and management of several plant viruses that have caused serious epidemics and been significant in the agricultural development of the Salinas Valley during the 20th century. Beet curly top virus (BCTV) almost destroyed the newly established sugarbeet industry soon after its establishment in the 1870s. A combination of resistant varieties, cultural management of beet crops to provide early plant emergence and development, and a highly coordinated beet leafhopper vector scouting and spray programme have achieved adequate control of BCTV. These programmes were first developed by the USDA and still operate. Lettuce mosaic virus was first recognized as causing a serious disease of lettuce crops in the 1930s. The virus is still a threat but it is controlled by a lettuce-free period in December and a seed certification programme that allows only seed lots with less than one infected seed in 30000 to be grown. 'Virus Yellows' is a term used to describe a complex of yellows inducing viruses which affect mainly sugarbeet and lettuce. These viruses include Beet yellows virus and Beet western yellows virus. During the 1950s, the complex caused significant yield losses to susceptible crops in the Salinas Valley. A beet-free period was introduced and is still used for control. The fungus-borne rhizomania disease of sugarbeet caused by Beet necrotic yellow vein virus was first detected in Salinas Valley in 1983. Assumed to have been introduced from Europe, this virus has now become widespread in California wherever beets are grown and crop losses can be as high as 100%. Movement of infested soil and beets accounts for its spread throughout the beet-growing regions of the United States. Control of rhizomania

  8. Taste processing in Drosophila larvae

    PubMed Central

    Apostolopoulou, Anthi A.; Rist, Anna; Thum, Andreas S.

    2015-01-01

    The sense of taste allows animals to detect chemical substances in their environment to initiate appropriate behaviors: to find food or a mate, to avoid hostile environments and predators. Drosophila larvae are a promising model organism to study gustation. Their simple nervous system triggers stereotypic behavioral responses, and the coding of taste can be studied by genetic tools at the single cell level. This review briefly summarizes recent progress on how taste information is sensed and processed by larval cephalic and pharyngeal sense organs. The focus lies on several studies, which revealed cellular and molecular mechanisms required to process sugar, salt, and bitter substances. PMID:26528147

  9. Cloning and genomic nucleotide sequence of the matrix attachment region binding protein from the halotolerant alga Dunaliella salina.

    PubMed

    Wang, Peng-Ju; Wang, Tian-Yun; Wang, Ya-Feng; Yang, Rui; Li, Zhao-Xi

    2013-07-01

    In our previous study, the sequence of a matrix attachment region binding protein (MBP) cDNA was cloned from the unicellular green alga Dunaliella salina. However, the nucleotide sequence of this gene has not been reported so far. In this paper, the nucleotide sequence of MBP was cloned and characterized, and its gene copy number was determined. The MBP nucleotide sequence is 5641 bp long, and interrupted by 12 introns ranging from 132 to 562 bp. All the introns in the D. salina MBP gene have orthodox splice sites, exhibiting GT at the 5' end and AG at the 3' end. Southern blot analysis showed that MBP only has one copy in the D. salina genome. PMID:22961592

  10. Cloning and genomic nucleotide sequence of the matrix attachment region binding protein from the halotolerant alga Dunaliella salina.

    PubMed

    Wang, Peng-Ju; Wang, Tian-Yun; Wang, Ya-Feng; Yang, Rui; Li, Zhao-Xi

    2013-07-01

    In our previous study, the sequence of a matrix attachment region binding protein (MBP) cDNA was cloned from the unicellular green alga Dunaliella salina. However, the nucleotide sequence of this gene has not been reported so far. In this paper, the nucleotide sequence of MBP was cloned and characterized, and its gene copy number was determined. The MBP nucleotide sequence is 5641 bp long, and interrupted by 12 introns ranging from 132 to 562 bp. All the introns in the D. salina MBP gene have orthodox splice sites, exhibiting GT at the 5' end and AG at the 3' end. Southern blot analysis showed that MBP only has one copy in the D. salina genome.

  11. LIPID PRODUCTION BY DUNALIELLA SALINA IN BATCH CULTURE: EFFECTS OF NITROGEN LIMITATION AND LIGHT INTENSITY

    SciTech Connect

    Weldy, C.S.; Huesemann, M.

    2007-01-01

    Atmospheric carbon dioxide (CO2) concentrations are increasing and may cause unknown deleterious environmental effects if left unchecked. The Intergovernmental Panel on Climate Change (IPCC) has predicted in its latest report a 2°C to 4°C increase in global temperatures even with the strictest CO2 mitigation practices. Global warming can be attributed in large part to the burning of carbon-based fossil fuels, as the concentration of atmospheric CO2 is directly related to the burning of fossil fuels. Biofuels which do not add CO2 to the atmosphere are presently generated primarily from terrestrial plants, i.e., ethanol from corn grain and biodiesel from soybean oil. The production of biofuels from terrestrial plants is severely limited by the availability of fertile land. Lipid production from microalgae and its corresponding biodiesel production have been studied since the late 1970s but large scale production has remained economically infeasible due to the large costs of sterile growing conditions required for many algal species. This study focuses on the potential of the halophilic microalgae species Dunaliella salina as a source of lipids and subsequent biodiesel production. The lipid production rates under high light and low light as well as nitrogen suffi cient and nitrogen defi cient culture conditions were compared for D. salina cultured in replicate photobioreactors. The results show (a) cellular lipid content ranging from 16 to 44% (wt), (b) a maximum culture lipid concentration of 450mg lipid/L, and (c) a maximum integrated lipid production rate of 46mg lipid/L culture*day. The high amount of lipids produced suggests that D. salina, which can be mass-cultured in non-sterile outdoor ponds, has strong potential to be an economically valuable source for renewable oil and biodiesel production.

  12. Lipid Production by Dunaliella salina in Batch Culture: Effects of Nitrogen Limitation and Light Intensity

    SciTech Connect

    Weldy, Chad S.; Huesemann, Michael H.

    2007-01-01

    Atmospheric carbon dioxide (CO2) concentrations are increasing and will cause unknown deleterious environmental effects if left unchecked. The Intergovernmental Panel on Climate Change (IPCC) has predicted in its latest report a 2ºC to 4ºC increase in global temperatures even with the strictest CO2 mitigation practices. Global warming can be attributed to in large part to the burning of carbon-based fossil fuels, as the concentration of atmospheric CO2 is directly related to the burning of fossil fuels. Biofuels which do not add CO2 to the atmosphere are presently generated primarily from terrestrial plants, i.e., ethanol from corn grain and biodiesel from soybean oil. The production of biofuels from terrestrial plants is severely limited by the availability of fertile land. Lipid production from microalgae and its corresponding biodiesel production have been studied since the late 1970’s but large scale production was determined to be economically unfeasible due to the large costs of sterile growing conditions required for many algal species. This study focuses on the potential to use the halophilic microalgae species Dunaliella salina as a source of lipids and subsequently for biodiesel production. The lipid production rates were compared for D. salina cultured in replicate photobioreactors under high light and low light as well as nitrogen sufficient and nitrogen deficient culture conditions. The results show (a) cellular lipid content ranging from 16 to 44% (wt), (b) a maximum culture lipid concentration of 450 mg lipid/L, and (c) a maximum integrated lipid production rate of 46 mg lipid/L culture*day. The high amount of lipids produced suggests that D. salina, which can be mass-cultured in non-sterile outdoor ponds, has a strong potential to be an economically valuable source for renewable oil and biodiesel production.

  13. DsHsp90 is involved in the early response of Dunaliella salina to environmental stress.

    PubMed

    Wang, Si-Jia; Wu, Ming-Jie; Chen, Xiang-Jun; Jiang, Yan; Yan, Yong-Bin

    2012-01-01

    Heat shock protein 90 (Hsp90) is a molecular chaperone highly conserved across the species from prokaryotes to eukaryotes. Hsp90 is essential for cell viability under all growth conditions and is proposed to act as a hub of the signaling network and protein homeostasis of the eukaryotic cells. By interacting with various client proteins, Hsp90 is involved in diverse physiological processes such as signal transduction, cell mobility, heat shock response and osmotic stress response. In this research, we cloned the dshsp90 gene encoding a polypeptide composed of 696 amino acids from the halotolerant unicellular green algae Dunaliella salina. Sequence alignment indicated that DsHsp90 belonged to the cytosolic Hsp90A family. Further biophysical and biochemical studies of the recombinant protein revealed that DsHsp90 possessed ATPase activity and existed as a dimer with similar percentages of secondary structures to those well-studied Hsp90As. Analysis of the nucleotide sequence of the cloned genomic DNA fragment indicated that dshsp90 contained 21 exons interrupted by 20 introns, which is much more complicated than the other plant hsp90 genes. The promoter region of dshsp90 contained putative cis-acting stress responsive elements and binding sites of transcriptional factors that respond to heat shock and salt stress. Further experimental research confirmed that dshsp90 was upregulated quickly by heat and salt shock in the D. salina cells. These findings suggested that dshsp90 might serve as a component of the early response system of the D. salina cells against environmental stresses.

  14. Depositional and subrosional Salina halite-bed terminations in northeastern Ohio are structurally controlled

    SciTech Connect

    Coogan, A.H.; Peng, S. . Dept. of Geology)

    1994-04-01

    Halite bed-bearing Silurian Salina Group units B through F-4 occur in the subsurface of northeastern Ohio where they have been restudied in a five county (Ashtabula, Geauga, Lake, Portage, Trumbull) area of the eastern interior salt basin at the edge of the Appalachian Basin. Three major factors affect the distributional pattern of the salts. First is the underlying topography, especially the presence of thick (reef-like) Lockport Dolomite over a basement gravity and magnetic high on the west side of the study area. Second is the preferential subsidence along fault zones which bound the depositional limits of some salts, for example the southern B salt edge at the Suffield Fault Zone. Third is the patterned removal of salt in the subsurface in northeast Ashtabula County along northwest trending fault zones. The F-2, F-1 and D salts progressively disappear to the northeast in Ashtabula County, toward Lake Erie and the Pennsylvania border in northwest trending bands which coincide with identified lineaments in adjacent Pennsylvania, e.g. the Home-Gallizen lineament or are subparallel to it and similar ones e.g. the Blaisville-Broad Top and Tyrone-Mount Union lineaments. The cause of the progressively deeper removal of halite beds from the Salina F-2, F-1, D and B units can be attributed to fresh or brackish water influx and subrosion below the sub-Oriskany (Acadian) unconformity. No salt beds are found shallower than 300 feet below the Oriskany horizon base. It appears that maps of Salina salt beds reflect penecontemporaneous Paleozoic structural (hence topographic) features and hydrologic regimes.

  15. Biology of Paenibacillus larvae, a deadly pathogen of honey bee larvae.

    PubMed

    Ebeling, Julia; Knispel, Henriette; Hertlein, Gillian; Fünfhaus, Anne; Genersch, Elke

    2016-09-01

    The gram-positive bacterium Paenibacillus larvae is the etiological agent of American Foulbrood of honey bees, a notifiable disease in many countries. Hence, P. larvae can be considered as an entomopathogen of considerable relevance in veterinary medicine. P. larvae is a highly specialized pathogen with only one established host, the honey bee larva. No other natural environment supporting germination and proliferation of P. larvae is known. Over the last decade, tremendous progress in the understanding of P. larvae and its interactions with honey bee larvae at a molecular level has been made. In this review, we will present the recent highlights and developments in P. larvae research and discuss the impact of some of the findings in a broader context to demonstrate what we can learn from studying "exotic" pathogens. PMID:27394713

  16. Valorization of the aqueous phase obtained from hydrothermally treated Dunaliella salina remnant biomass.

    PubMed

    Pirwitz, Kristin; Rihko-Struckmann, Liisa; Sundmacher, Kai

    2016-11-01

    Up to 90% of Dunaliella salina biomass remains unused after extraction of the main product β-carotene. The potential of mild hydrothermal liquefaction (HTL) to exploit this biomass as a source of valuable by-products was assessed. The results indicate that 80% of the remnant was converted into glucose by mild HTL (100°C, 0min). The recovered glucose was successfully used as a carbon source to cultivate biotechnologically relevant microorganisms, namely Chlorella vulgaris, Escherichia coli and Saccharomyces cerevisiae. Furthermore, the analysis of energy demand and operating costs confirms the beneficial effect of mild liquefaction on the overall process economics of algal β-carotene production. PMID:27475332

  17. Valorization of the aqueous phase obtained from hydrothermally treated Dunaliella salina remnant biomass.

    PubMed

    Pirwitz, Kristin; Rihko-Struckmann, Liisa; Sundmacher, Kai

    2016-11-01

    Up to 90% of Dunaliella salina biomass remains unused after extraction of the main product β-carotene. The potential of mild hydrothermal liquefaction (HTL) to exploit this biomass as a source of valuable by-products was assessed. The results indicate that 80% of the remnant was converted into glucose by mild HTL (100°C, 0min). The recovered glucose was successfully used as a carbon source to cultivate biotechnologically relevant microorganisms, namely Chlorella vulgaris, Escherichia coli and Saccharomyces cerevisiae. Furthermore, the analysis of energy demand and operating costs confirms the beneficial effect of mild liquefaction on the overall process economics of algal β-carotene production.

  18. Map of the Rinconada and Reliz Fault Zones, Salinas River Valley, California

    USGS Publications Warehouse

    Rosenberg, Lewis I.; Clark, Joseph C.

    2009-01-01

    The Rinconada Fault and its related faults constitute a major structural element of the Salinas River valley, which is known regionally, and referred to herein, as the 'Salinas Valley'. The Rinconada Fault extends 230 km from King City in the north to the Big Pine Fault in the south. At the south end of the map area near Santa Margarita, the Rinconada Fault separates granitic and metamorphic crystalline rocks of the Salinian Block to the northeast from the subduction-zone assemblage of the Franciscan Complex to the southwest. Northwestward, the Rinconada Fault lies entirely within the Salinian Block and generally divides this region into two physiographically and structurally distinct areas, the Santa Lucia Range to the west and the Salinas Valley to the east. The Reliz Fault, which continues as a right stepover from the Rinconada Fault, trends northwestward along the northeastern base of the Sierra de Salinas of the Santa Lucia Range and beyond for 60 km to the vicinity of Spreckels, where it is largely concealed. Aeromagnetic data suggest that the Reliz Fault continues northwestward another 25 km into Monterey Bay, where it aligns with a high-definition magnetic boundary. Geomorphic evidence of late Quaternary movement along the Rinconada and Reliz Fault Zones has been documented by Tinsley (1975), Dibblee (1976, 1979), Hart (1976, 1985), and Klaus (1999). Although definitive geologic evidence of Holocene surface rupture has not been found on these faults, they were regarded as an earthquake source for the California Geological Survey [formerly, California Division of Mines and Geology]/U.S. Geological Survey (CGS/USGS) Probabilistic Seismic Hazards Assessment because of their postulated slip rate of 1+-1 mm/yr and their calculated maximum magnitude of 7.3. Except for published reports by Durham (1965, 1974), Dibblee (1976), and Hart (1976), most information on these faults is unpublished or is contained in theses, field trip guides, and other types of reports

  19. Changes in ultrastructure and responses of antioxidant systems of algae (Dunaliella salina) during acclimation to enhanced ultraviolet-B radiation.

    PubMed

    Tian, Jiyuan; Yu, Juan

    2009-12-01

    Because of depletion of the stratospheric ozone layer, levels of solar ultraviolet-B (UV-B) radiation (280-315 nm), which penetrates the water column to an ecologically-significant depth, are increasing. In order to assess changes in ultrastructure and responses of antioxidant systems of algae during acclimation to enhanced ultraviolet-B radiation, Dunaliella salina was treated with higher dose of UV-B radiation (13.2 kJm(-2) d(-1) dose) in this study. As compared to the control panel (8.8 kJm(-2) d(-1)), the treatment D. salina had many changes in ultrastructures: (1) thylakoids became swelled, and some of them penetrated into the pyrenoid; (2) lipid globules accumulated; (3) the amounts of starch grains increased; (4) cristae of mitochondria disintegrated; (5) inclusions in vacuoles reduced; and (6) cisternae of Golgi dictyosomes became loose and swollen. Enhanced UV-B irradiation also induced different responses of the antioxidant systems in D. salina: (1) contents of TBARS (thiobarbituric acid reacting substance) and H(2)O(2) increased significantly (p<0.05); (2) levels of MAAs (mycosporine-like amino acids) increased at the beginning and subsequently decreased, and finally they leveled off at lower values; (3) there were not apparent variations for carotenoid contents, and contents of chlorophyll a presented a trend of initial increase and ultimate decrease; (4) both ascorbate and glutathione contents increased significantly (p<0.05); and (5) for the enzyme activities, POD activities increased remarkably (p<0.05), and SOD activities declined apparently (p<0.05), and CAT activity in D. salina had slight variations (p>0.05). In addition, growth curve displayed that enhanced UV-B radiation prominently inhibited increase of cell concentration when compared with control panel (p<0.05). Our results indicated that enhanced UV-B radiation caused ultrastructural changes of D. salina and induced different responses of antioxidant systems in D. salina. PMID:19818642

  20. Changes in ultrastructure and responses of antioxidant systems of algae (Dunaliella salina) during acclimation to enhanced ultraviolet-B radiation.

    PubMed

    Tian, Jiyuan; Yu, Juan

    2009-12-01

    Because of depletion of the stratospheric ozone layer, levels of solar ultraviolet-B (UV-B) radiation (280-315 nm), which penetrates the water column to an ecologically-significant depth, are increasing. In order to assess changes in ultrastructure and responses of antioxidant systems of algae during acclimation to enhanced ultraviolet-B radiation, Dunaliella salina was treated with higher dose of UV-B radiation (13.2 kJm(-2) d(-1) dose) in this study. As compared to the control panel (8.8 kJm(-2) d(-1)), the treatment D. salina had many changes in ultrastructures: (1) thylakoids became swelled, and some of them penetrated into the pyrenoid; (2) lipid globules accumulated; (3) the amounts of starch grains increased; (4) cristae of mitochondria disintegrated; (5) inclusions in vacuoles reduced; and (6) cisternae of Golgi dictyosomes became loose and swollen. Enhanced UV-B irradiation also induced different responses of the antioxidant systems in D. salina: (1) contents of TBARS (thiobarbituric acid reacting substance) and H(2)O(2) increased significantly (p<0.05); (2) levels of MAAs (mycosporine-like amino acids) increased at the beginning and subsequently decreased, and finally they leveled off at lower values; (3) there were not apparent variations for carotenoid contents, and contents of chlorophyll a presented a trend of initial increase and ultimate decrease; (4) both ascorbate and glutathione contents increased significantly (p<0.05); and (5) for the enzyme activities, POD activities increased remarkably (p<0.05), and SOD activities declined apparently (p<0.05), and CAT activity in D. salina had slight variations (p>0.05). In addition, growth curve displayed that enhanced UV-B radiation prominently inhibited increase of cell concentration when compared with control panel (p<0.05). Our results indicated that enhanced UV-B radiation caused ultrastructural changes of D. salina and induced different responses of antioxidant systems in D. salina.

  1. Ganzfeld ERG in zebrafish larvae.

    PubMed

    Seeliger, Mathias W; Rilk, Albrecht; Neuhauss, Stephan C F

    2002-01-01

    In developmental biology, zebrafish are widely used to study the impact of mutations. The fast pace of development allows for a definitive morphological evaluation of the phenotype usually 5 days post fertilization (dpf). At that age, a functional analysis is already feasible using electroretinographic (ERG) methods. Corneal Ganzfeld ERGs were recorded with a glass microelectrode in anaesthetized, dark-adapted larvae aged 5 dpf, using a platinum wire beneath a moist paper towel as reference. ERG protocols included flash, flicker, and ON/OFF stimuli, both under scotopic and photopic conditions. Repetitive, isoluminant stimuli were used to assess the dynamic effect of pharmacological agents on the ERG. Single flash, flicker, and ON/OFF responses had adequately matured at this point to be informative. Typical signs of the cone dominance were the small scotopic a-wave and the large OFF responses. The analysis of consecutive single traces was possible because of the lack of EKG, breathing, and blink artefacts. After application of APB, which selectively blocks the ON channel via the mGluR6 receptor, the successive loss of the b-wave could be observed, which was quite different from the deterioration of the ERG after a circulatory arrest. The above techniques allowed to reliably obtain Ganzfeld ERGs in larvae aged 5 dpf. This underlines the important role of the zebrafish as a model for the functional analysis of mutations disrupting the visual system. PMID:11949809

  2. Molecular Characterization of Ancylostoma braziliense Larvae in a Patient with Hookworm-Related Cutaneous Larva Migrans

    PubMed Central

    Joncour, Alexandre Le; Lacour, Sandrine A.; Lecso, Gabriel; Regnier, Stéphanie; Guillot, Jacques; Caumes, Eric

    2012-01-01

    We report a case of hookworm-related cutaneous larva migrans diagnosed microscopically. Viable hookworm larvae were found by microscopic examination of a skin scraping from follicular lesions. Amplification and sequencing of the internal transcribed spacer 2 allowed the specific identification of the larvae as Ancylostoma braziliense. PMID:22556085

  3. Identification of the glycerol kinase gene and its role in diapause embryo restart and early embryo development of Artemia sinica.

    PubMed

    Cheng, Cheng; Yao, Feng; Chu, Bing; Li, Xuejie; Liu, Yan; Wu, Yang; Mei, Yanli; Wang, Peisheng; Hou, Lin; Zou, Xiangyang

    2014-03-01

    Glycerol kinase (GK) catalyzes the rate-limiting step in glycerol utilization by transferring a phosphate from ATP to glycerol, yielding glycerol 3-phosphate, which is an important intermediate for both energy metabolism and glycerolipid production. Artemia sinica has an unusual diapause process under stress conditions of high salinity, low temperature and lack of food. In the process, diapause embryos of A. sinica (brine shrimp) accumulate high concentrations of glycerol as a cryoprotectant to prevent low temperature damage to embryos. Upon embryo restart, glycerol is converted into glucose and other carbohydrates. Therefore, GK plays an important role in the diapause embryo restart process. However, the role of GK in diapause termination of embryo development in A. sinica remains unknown. In the present study, a 2096 bp full-length cDNA of gk from A. sinica (As-gk) was obtained, encoding putative 551 amino acids, 60.6 kDa protein. As a crucial enzyme in glycerol uptake and metabolism, GK has been conserved structurally and functionally during evolution. The expression pattern of As-gk was investigated by quantitative real-time PCR and Western blotting. Expression locations of As-gk were analyzed using in situ hybridization. As-gk was widely distributed in the early embryo and several main parts of Artemia after differentiation. The expression of As-GK was also induced by stresses such as cold exposure and high salinity. This initial research into the expression pattern and stress response of GK in Artemia provides a sound basis for further understanding of the function and regulation of genes in early embryonic development in A. sinica and the stress response. PMID:24365596

  4. beta-Hydroxybutyrate in developing nauplii of brine shrimp (Artemia franciscana K.) under feeding and non-feeding conditions.

    PubMed

    Weltzien, F A; Hemre, G I; Evjemo, J O; Olsen, Y; Fyhn, H J

    2000-01-01

    Body content of beta-hydroxybutyrate, and individual dry mass, carbon content, and survival rate, were studied in developing nauplii of the brine shrimp Artemia franciscana K. from hatching to 96-97 h post hatching at 27 +/- 1 degrees C. The effect of two diets was studied in the experiment: Super Selco (SS) with a high lipid content; and Protein Selco (PS) with a high protein content. A starving group (S) was used as reference. The level of beta-hydroxybutyrate at hatching was 0.6 nmol.ind-1; it increased to 1.0-1.5 nmol.ind-1 in the SS- and S-groups, while in the PS-group it remained stable between 0.6-0.8 nmol.ind-1. At 60-80 h post hatch in the SS- and S-groups, the levels of beta-hydroxybutyrate were similar to the initial levels. The survival rate remained higher than 95% until 24 h post hatching in all groups. At the end of the experiment, the survival rate was 63% in the PS-group, 13% in the S-group and 3% in the SS-group. The Artemia nauplii individual dry mass and carbon content remained relatively stable in the SS-group; both parameters showed a significant increase in the PS-group and a significant decrease in the S-group. The results suggest that Artemia nauplii utilise ketone bodies as a fuel during development and growth, but that ketone catabolism may be overloaded by excessive lipid feeding resulting in increased mortality and possibly a ketotic acidosis. PMID:10840642

  5. Naked eye instant reversible sensing of Cu(2+) and its in situ imaging in live brine shrimp Artemia.

    PubMed

    Nair, Ratish R; Raju, M; Patel, Neha P; Raval, Ishan H; Suresh, E; Haldar, Soumya; Chatterjee, Pabitra B

    2015-08-21

    A Cu(2+)-specific colorimetric reversible fluorescent receptor was designed and synthesized which showed a naked eye observable colour change from colourless to pink on addition of an aqueous buffer (pH 7.4) solution of 30 ppb Cu(2+). Short response time (≤5 s) and low detection limit (nearly 3 ppb) make suitable as a reliable "dip-in" open eye sensor for Cu(2+). Bio-imaging application in live brine shrimp Artemia enabled to detect Cu(2+) at as low as 10 ppb exposure. PMID:26145434

  6. Changes in developmental capacity of artemia cyst and chromosomal aberrations in lettuce seeds flown aboard Salyut-7 (Biobloc III experiment)

    NASA Astrophysics Data System (ADS)

    Nevzgodina, V.; Kovalev, E. E.; Maximova, E. N.; Gaubin, Y.; Planel, H.; Gasset, G.; Pianezzi, B.; Clegg, J.

    This paper gives the results of investigations performed on the first container (A) of the Biobloc III experiment, flown aboard the orbital station Salyut 7 for 40 days. The space flight resulted in a decreased developmental capacity of Artemia cysts, hit or not hit by the HZE particles. No effect was observed in cysts in bulk. A synergetic effect of microgravity and gamma pre irradiation is described. The germination of in-flight lettuce seeds was decreased. The space flight resulted also in a higher percentage of cells with chromosomal aberrations. Relations between biological response, TEL and location of HZE particles are discussed.

  7. Chronic toxicity of arsenic to the Great Salt Lake brine shrimp, Artemia franciscana.

    PubMed

    Brix, Kevin V; Cardwell, Rick D; Adams, William J

    2003-02-01

    We determined the chronic toxicity of arsenic (sodium arsenate) to the Great Salt Lake brine shrimp, Artemia franciscana. Chronic toxicity was determined by measuring the adverse effects of arsenic on brine shrimp growth, survival, and reproduction under intermittent flow-through conditions. The study commenced with <24-h-old nauplii, continued through reproduction of the parental generation, and ended after 28 days of exposure. The concentrations tested were 4, 8, 15, 31, and 56mg/L dissolved arsenic. The test was conducted using water from the Great Salt Lake, Utah as the dilution water. Adult survival was the most sensitive biological endpoint, with growth and reproduction somewhat less sensitive than survival. The no observed effect concentration (NOEC) for survival was 8mg/L, and the lowest observed effect concentration (LOEC) was 15mg/L dissolved arsenic. The LOEC for growth and reproduction was greater than the highest concentration tested, 56mg/L. Based on survival, the final chronic value (geometric mean of the NOEC and LOEC) was 11mg/L dissolved arsenic. The F(1) generation appeared to acclimate to the prior arsenic exposure of the parental generation and was significantly less sensitive than the parental generation. For example, survival for the F(1) generation through day 12 was 100% in 56mg/L dissolved arsenic, compared to 26% for the parental generation. Growth of the F(1) generation was significantly less than that of the parental generation across all concentrations including the control, indicating a generational difference in brine shrimp growth rather than an arsenic effect. This study represents one of the few full life cycle toxicity tests conducted with brine shrimp. PMID:12550094

  8. Liposomes with diverse compositions are protected during desiccation by LEA proteins from Artemia franciscana and trehalose.

    PubMed

    Moore, Daniel S; Hansen, Richard; Hand, Steven C

    2016-01-01

    Intracellular accumulation of Late Embryogenesis Abundant (LEA) proteins and the disaccharide trehalose is associated with cellular desiccation tolerance in a number of animal species. Two LEA proteins from anhydrobiotic embryos of the brine shrimp Artemia franciscana were tested for the ability to protect liposomes of various compositions against desiccation-induced damage in the presence and absence of trehalose. Damage was assessed by carboxyfluorescein leakage after drying and rehydration. Further, using a cytoplasmic-localized (AfrLEA2) and a mitochondrial-targeted (AfrLEA3m) LEA protein allowed us to evaluate whether each may preferentially stabilize membranes of a particular lipid composition based on the protein's subcellular location. Both LEA proteins were able to offset damage during drying of liposomes that mimicked the lipid compositions of the inner mitochondrial membrane (with cardiolipin), outer mitochondrial membrane, and the inner leaflet of the plasma membrane. Thus liposome stabilization by AfrLEA3m or AfrLEA2 was not dependent on lipid composition, provided physiological amounts of bilayer and non-bilayer-forming lipids were present (liposomes with a non-biological composition of 100% phosphatidylcholine were not protected by either protein). Additive protection by LEA proteins plus trehalose was dependent on the lipid composition of the target membrane. Minimal additional damage occurred to liposomes stored at room temperature in the dried state for one week compared to liposomes rehydrated after 24h. Consistent with the ability to stabilize lipid bilayers, molecular modeling of the secondary structures for AfrLEA2 and AfrLEA3m revealed bands of charged amino acids similar to other amphipathic proteins that interact directly with membranes. PMID:26518519

  9. Metabolic restructuring during energy-limited states: insights from Artemia franciscana embryos and other animals.

    PubMed

    Hand, Steven C; Menze, Michael A; Borcar, Apu; Patil, Yuvraj; Covi, Joseph A; Reynolds, Julie A; Toner, Mehmet

    2011-05-01

    Many life history stages of animals that experience environmental insults enter developmental arrested states that are characterized by reduced cellular proliferation, with or without a concurrent reduction in overall metabolism. In the case of the most profound metabolic arrest reported in invertebrates, i.e., anaerobic quiescence in Artemia franciscana embryos, acidification of the intracellular milieu is a major factor governing catabolic and anabolic downregulation. Release of ions from intracellular compartments is the source for approximately 50% of the proton equivalents needed for the 1.5 unit acidification that is observed. Recovery from the metabolic arrest requires re-sequestration of the protons with a vacuolar-type ATPase (V-ATPase). The remarkable facet of this mechanism is the ability of embryonic cells to survive the dissipation of intracellular ion gradients. Across many diapause-like states, the metabolic reduction and subsequent matching of energy demand is accomplished by shifting energy metabolism from oxidative phosphorylation to aerobic glycolysis. Molecular pathways that are activated to induce these resilient hypometabolic states include stimulation of the AMP-activated protein kinase (AMPK) and insulin signaling via suite of daf (dauer formation) genes for diapause-like states in nematodes and insects. Contributing factors for other metabolically depressed states involve hypoxia-inducible factor-1 and downregulation of the pyruvate dehydrogenase complex. Metabolic similarities between natural states of stasis and some cancer phenotypes are noteworthy. Reduction of flux through oxidative phosphorylation helps prevent cell death in certain cancer types, similar to the way it increases viability of dauer stages in Caenorhabditis elegans. Mechanisms that underlie natural stasis are being used to pre-condition mammalian cells prior to cell biostabilization and storage.

  10. The effects of feeding with synbiotic (Pediococcus acidilactici and fructooligosaccharide) enriched adult Artemia on skin mucus immune responses, stress resistance, intestinal microbiota and performance of angelfish (Pterophyllum scalare).

    PubMed

    Azimirad, Mahmood; Meshkini, Saeed; Ahmadifard, Nasrollah; Hoseinifar, Seyed Hossein

    2016-07-01

    The aim of this study was to evaluate the effects of feeding on synbiotic (Pediococcus acidilactici and fructooligosaccharide) enriched adult Artemia franciscana on skin mucus immune responses, stress resistance, intestinal microbiota and growth performance of angelfish (Pterophyllum scalare). Three hundred and sixty fish with initial weight 3.2 ± 0.13 g were randomly divided into twelve aquaria (50 L) assigned to four groups in triplicates. Fish were fed for 7 weeks with dietary treatments, including treatment 1: feeding adult Artemia without enrichment (control group), treatment 2: feeding adult Artemia enriched with lyophilised probiotic P. acidilactici (700 mg L(-1)), 3: feeding adult Artemia enriched with prebiotic fructooligosaccharide (FOS) (100 mg L(-1)), group 4: feeding adult Artemia enriched with synbiotic (P. acidilactici (700 mg L(-1)) + FOS (100 mg L(-1))). Skin mucus immune responses (lysozyme activity, total Immunoglobulin and protease), stress resistance against environmental stress (acute decrease of temperature and increase salinity), intestinal microbiota as well as growth indices were measured at the end of feeding trial. Artemia enriched with synbiotic significantly improved growth performance compared to other treatments (P < 0.05). The highest weight gain and specific growth rate (SGR) was observed in synbiotic fed fish (P < 0.05). Compared to the other treatments, the population of lactic acid bacteria was significantly higher in the intestinal microbiota of fish fed synbiotic supplemented diet (P < 0.05). In the environmental stress challenge test, the maximum resistance to abrupt decrease of temperature (17 °C) or elevation of salinity (12 g per liter) was observed in the synbiotic treatment. Also, the total immunoglobulin and lysozyme activity level of skin mucus was significantly elevated in fish fed Artemia enriched with synbiotic (P < 0.05). These results revealed that feeding angelfish with synbiotic

  11. Anaerobic co-digestion of the marine microalga Nannochloropsis salina with energy crops.

    PubMed

    Schwede, Sebastian; Kowalczyk, Alexandra; Gerber, Mandy; Span, Roland

    2013-11-01

    Anaerobic co-digestion of corn silage with the marine microalga Nannochloropsis salina was investigated under batch and semi-continuous conditions. Under batch conditions process stability and biogas yields significantly increased by microalgae addition. During semi-continuous long-term experiments anaerobic digestion was stable in corn silage mono- and co-digestion with the algal biomass for more than 200 days. At higher organic loading rates (4.7 kg volatile solids m(-3)d(-1)) inhibition and finally process failure occurred in corn silage mono-digestion, whereas acid and methane formation remained balanced in co-digestion. The positive influences in co-digestion can be attributed to an adjusted carbon to nitrogen ratio, enhanced alkalinity, essential trace elements and a balanced nutrient composition. The results suggest that N. salina biomass is a suitable feedstock for anaerobic co-digestion of energy crops, especially for regions with manure scarcity. Enhanced process stability may result in higher organic loading rates or lower digester volumes. PMID:24071442

  12. Design of a ground-water-quality monitoring network for the Salinas River basin, California

    USGS Publications Warehouse

    Showalter, P.K.; Akers, J.P.; Swain, L.A.

    1984-01-01

    A regional ground-water quality monitoring network for the entire Salinas River drainage basin was designed to meet the needs of the California State Water Resources Control Board. The project included phase 1--identifying monitoring networks that exist in the region; phase 2--collecting information about the wells in each network; and phase 3--studying the factors--such as geology, land use, hydrology, and geohydrology--that influence the ground-water quality, and designing a regional network. This report is the major product of phase 3. Based on the authors ' understanding of the ground-water-quality monitoring system and input from local offices, an ideal network was designed. The proposed network includes 317 wells and 8 stream-gaging stations. Because limited funds are available to implement the monitoring network, the proposed network is designed to correspond to the ideal network insofar as practicable, and is composed mainly of 214 wells that are already being monitored by a local agency. In areas where network wells are not available, arrangements will be made to add wells to local networks. The data collected by this network will be used to assess the ground-water quality of the entire Salinas River drainage basin. After 2 years of data are collected, the network will be evaluated to test whether it is meeting the network objectives. Subsequent network evaluations will be done very 5 years. (USGS)

  13. DsCaf1 is involved in environmental stress response of Dunaliella salina.

    PubMed

    Chen, Xiang-Jun; Zhang, Xin-Hang; Hu, Li-Dan; Zhang, Jia-Quan; Jiang, Yan; Yang, Yi; Yan, Yong-Bin

    2016-01-01

    Regulation of mRNA fates can alter the gene-expression profile promptly and specifically. Deadenylation is a process of which the poly(A) tail is degraded by deadenylases. By regulating mRNA turnover, deadenylases are involved in various vital cellular processes including stress responses. However, it is unclear whether deadenylases play a role in the adaption/tolerance of extremophiles. In this research, we cloned the deadenylase caf1 from Dunaliella salina (dscaf1), a unicellular green alga with exceptional halotolerance. In silicon analysis indicated that compared with the mesophilic alga Chlamydomonas reinhardtii caf1, dscaf1 promoter contained more elements responsive to abiotic stresses. Dscaf1 had an extremely high expression level under hypersaline conditions. When the D. salina cells were subject to stress shock, a two-stage response was observed for dscaf1 expression. The mRNA level of dscaf1 had an immediate 2-4 fold increase and followed by an ∼10 fold increase after hyperosmotic, heat or UV treatment, while had an about 3 fold increase quickly followed by an abrupt decrease after hypoosmotic or cold shock. The dissimilarity in dscaf1 expression patterns suggested that DsCaf1 is a stress-responsive deadenylase with the ability to regulate fates of a specific group of mRNAs for a certain type of stress.

  14. Role of Lys281 in the Dunaliella salina (6-4) photolyase reaction.

    PubMed

    Zhang, Feiwei; Xu, Hui; Cao, Yu; Wen, Tao; Lin, Jiafu; Ma, Gen; Qiao, Dairong; Cao, Yi

    2011-01-01

    His(354) and His(358), two highly conserved histidines in Xenopus laevis (6-4) photolyase [equivalent to His(401) and His(405), in Dunaliella salina (6-4) photolyase], are critical for photoreactivation. They act as a base and an acid, respectively. However, the remaining high repair activity when the pH value is higher than the pKa of histidine suggests the involvement of other basic amino acids in photoreactivation. According to the results of in vivo enzyme assay and three-dimension structural model of Dunaliella salina (6-4) photolyase we hypothesized that Lys(281) might be involved in the photoreactivation over the pH range from 10.0 to 11.0. To test this, we generated two mutant forms of the (6-4) photolyase, K281G and K281R mutant, by overlap extension polymerase chain reaction, and performed the enzyme assay with these mutants. From these results we conclude that the Lys(281), which is highly conserved in (6-4) photolyases, participates in the photoreactivation and acts as an acid to donate a proton to His(401) when the environmental pH is higher than the pKa value of histidine.

  15. Phosphatidylinositol 4,5-bisphosphate phospholipase C and phosphomonoesterase in Dunaliella salina membranes

    SciTech Connect

    Einspahr, K.J.; Peeler, T.C.; Thompson, G.A. Jr. )

    1989-07-01

    In comparison with other cell organelles, the Dunaliella salina plasma membrane was found to be highly enriched in phospholipase C activity toward exogenous ({sup 3}H)phosphatidylinositol 4,5-bisphosphate (PIP{sub 2}). Based on release of ({sup 3}H)inositol phosphates, the plasma membrane exhibited a PIP{sub 2}-phospholipase C activity nearly tenfold higher than the nonplasmalemmal, nonchloroplast bottom phase (BP) membrane fraction and 47 times higher than the chloroplast membrane fraction. The majority of phospholipase activity was clearly of a phospholipase C nature since over 80% of ({sup 3}H)inositol phosphates released were recovered as ({sup 3}H)inositol trisphosphate (IP{sub 3}). These results suggest a plausible mechanism for the rapid breakdown of PIP{sub 2} and phosphatidylinositol 4-phosphate (PIP) following hypoosmotic shock. The authors have also examined some of the in vitro characteristics of the plasma membrane phospholipase C activity and have found it to be calcium sensitive, reaching maximal activity at 10 micromolar free (Ca{sup 2+}). They also report here that 100 micromolar GTP{gamma}S stimulates phospholipase C activity over a range of free (Ca{sup 2+}). Together, these results provide evidence that the plasma membrane PIP{sub 2}-phospholipase C of D. salina may be subject to Ca{sup 2+} and G-protein regulation.

  16. Comparison of sequences formed in Marine sabkha (subaerial) and salina (Subaqueous) settings-modern and ancient

    SciTech Connect

    Warren, J.K.; St. Kendall, C.G.

    1985-06-01

    Marine evaporites occurring in modern subaqueous (salina) settings and subaerial (sabkha) settings are different. Subaqueous Holocene evaporites occur as shoalingupward lacustrine sequences up to 10 m thick. They are evaporite dominated and are composed primarily of bottom-nucleated crystals that may be deposited as massive, laminated, or rippled units. Each coastal lake is dominated by laminated evaporites with subordinate carbonate sediments. In plan view, they show a well-developed bull's-eye pattern with a sulfate center and a carbonate rim. In contrast, subaerial (sabkha) evaporites occur as part of a laterally prograding, shoaling-upward, peritidal sequence in which the supratidal unit is usually no more than 1 m thick. Sabkha sequences are matrix dominated, not evaporite dominated, with the bulk of the sulfate phase occurring as diagenetic nodules, enteroliths, or diapirlike structures. These sulfates were formed during syndepositional diagenesis by replacement and displacement processes. The various facies of the sequence tend to accumulate in belts parallel with the shoreline. Relative to the sea level or the brine level, sabkhas tend to form over paleotopographic highs whereas salinas tend to occur in paleotopographic lows. Some of the characteristics that distinguish Holocene subaerial and subaqueous evaporite sequences can be used to do the same for similar ancient facies, even when gypsum has been converted to nodular anhydrite. The distinction is important for it can be used by explorationists in the oil industry to define the paleotopography of the associated underlying porous and nonporous carbonates.

  17. Workbook on Identification of Aedes Aegypti Larvae.

    ERIC Educational Resources Information Center

    Pratt, Harry D.; And Others

    This self-instructional booklet is designed to enable yellow fever control workers to identify the larvae of "Aedes aegypti." The morphological features of mosquito larvae are illustrated in this partially programed text, and the distinguishing features of "A. aegypti" indicated. A glossary is included. (AL)

  18. Evaluation of hydrologic conditions and nitrate concentrations in the Rio Nigua de Salinas alluvial fan aquifer, Salinas, Puerto Rico, 2002-03

    USGS Publications Warehouse

    Rodriguez, Jose M.

    2006-01-01

    A ground-water quality study to define the potential sources and concentration of nitrate in the Rio Nigua de Salinas alluvial fan aquifer was conducted between January 2002 and March 2003. The study area covers about 3,600 hectares of the coastal plain within the municipality of Salinas in southern Puerto Rico, extending from the foothills to the Caribbean Sea. Agriculture is the principal land use and includes cultivation of diverse crops, turf grass, bioengineered crops for seed production, and commercial poultry farms. Ground-water withdrawal in the alluvial fan was estimated to be about 43,500 cubic meters per day, of which 49 percent was withdrawn for agriculture, 42 percent for public supply, and 9 percent for industrial use. Ground-water flow in the study area was primarily to the south and toward a cone of depression within the south-central part of the alluvial fan. The presence of that cone of depression and a smaller one located in the northeastern quadrant of the study area may contribute to the increase in nitrate concentration within a total area of about 545 hectares by 'recycling' ground water used for irrigation of cultivated lands. In an area that covers about 405 hectares near the center of the Salinas alluvial fan, nitrate concentrations increased from 0.9 to 6.7 milligrams per liter as nitrogen in 1986 to 8 to 12 milligrams per liter as nitrogen in 2002. Principal sources of nitrate in the study area are fertilizers (used in the cultivated farmlands) and poultry farm wastes. The highest nitrogen concentrations were found at poultry farms in the foothills area. In the area of disposed poultry farm wastes, nitrate concentrations in ground water ranged from 25 to 77 milligrams per liter as nitrogen. Analyses for the stable isotope ratios of nitrogen-15/nitrogen-14 in nitrate were used to distinguish the source of nitrate in the coastal plain alluvial fan aquifer. Potential nitrate loads from areas under cultivation were estimated for the

  19. Enhancement of carotenoid biosynthesis in the green microalga Dunaliella salina with light-emitting diodes and adaptive laboratory evolution.

    PubMed

    Fu, Weiqi; Guðmundsson, Olafur; Paglia, Giuseppe; Herjólfsson, Gísli; Andrésson, Olafur S; Palsson, Bernhard O; Brynjólfsson, Sigurður

    2013-03-01

    There is a particularly high interest to derive carotenoids such as β-carotene and lutein from higher plants and algae for the global market. It is well known that β-carotene can be overproduced in the green microalga Dunaliella salina in response to stressful light conditions. However, little is known about the effects of light quality on carotenoid metabolism, e.g., narrow spectrum red light. In this study, we present UPLC-UV-MS data from D. salina consistent with the pathway proposed for carotenoid metabolism in the green microalga Chlamydomonas reinhardtii. We have studied the effect of red light-emitting diode (LED) lighting on growth rate and biomass yield and identified the optimal photon flux for D. salina growth. We found that the major carotenoids changed in parallel to the chlorophyll b content and that red light photon stress alone at high level was not capable of upregulating carotenoid accumulation presumably due to serious photodamage. We have found that combining red LED (75 %) with blue LED (25 %) allowed growth at a higher total photon flux. Additional blue light instead of red light led to increased β-carotene and lutein accumulation, and the application of long-term iterative stress (adaptive laboratory evolution) yielded strains of D. salina with increased accumulation of carotenoids under combined blue and red light.

  20. PESTICIDES AND THEIR METABOLITES IN THE HOMES AND URINE OF FARMWORKER CHILDREN LIVING IN THE SALINAS VALLEY, CA

    EPA Science Inventory

    This paper describes a study to test field methods for characterizing pesticide exposures to 20 farmworker children aged 5-27 months old living in the Salinas Valley of Monterey County, California. Methods for collecting house dust, indoor and outdoor air, dislodgeable residues ...

  1. 78 FR 1210 - Grand River Dam Authority; Notice of Telephone Meeting To Discuss the Salina Pumped Storage...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-08

    ... Energy Regulatory Commission Grand River Dam Authority; Notice of Telephone Meeting To Discuss the Salina... Grand River Dam Authority. (An RSVP is required. See paragraph f below.) c. FERC Contact: Stephen Bowler... Grand River Dam Authority (GRDA) is holding a technical meeting to discuss the results of the...

  2. Effects of Surface-Engineered Nanoparticle-Based Dispersants for Marine Oil Spills on the Model Organism Artemia franciscana

    PubMed Central

    2015-01-01

    Fine particles are under active consideration as alternatives to chemical dispersants for large-scale petroleum spills. Fine carbon particles with engineered surface chemistry have been shown to stabilize oil-in-water emulsions, but the environmental impacts of large-scale particle introduction to the marine environment are unknown. Here we study the impact of surface-engineered carbon-black materials on brine shrimp (Artemia franciscana) as a model marine microcrustacean. Mortality was characterized at 50–1000 mg/L, and levels of heat shock protein 70 (hsp70) were characterized at sublethal particle concentrations (25–50 mg/L). Functionalized carbon black (CB) nanoparticles were found to be nontoxic at all concentrations, while hydrophobic (annealed) and as-produced CB induced adverse effects at high concentrations. CB was also shown to adsorb benzene, a model hydrocarbon representing the more soluble and toxic low-molecular weight aromatic fraction of petroleum, but the extent of adsorption was insufficient to mitigate benzene toxicity to Artemia in coexposure experiments. At lower benzene concentrations (25–75 mg/L), coexposure with annealed and as-produced CB increased hsp70 protein levels. This study suggests that surface functionalization for increased hydrophilicity can not only improve the performance of CB-based dispersants but also reduce their adverse environmental impacts on marine organisms. PMID:24823274

  3. Effect of municipal waste water effluent upon the expression of Glutathione S-transferase isoenzymes of brine shrimp Artemia.

    PubMed

    Grammou, Athina; Papadimitriou, Chrisa; Samaras, Peter; Vasara, Eleni; Papadopoulos, Athanasios I

    2011-06-01

    Multiple isoenzymes of the detoxification enzyme family Glutathione S-transferase are expressed in the brine shrimp Artemia. The number of the major ones detected in crude extract by means of chromatofocusing varied between three and four, depending on the age. Two isoenzymes, one alkaline and one neutral (with corresponding isoelectric points of 8.5 and 7.2) appear to be dominant in all three developmental stages studied, (24, 48, and 72 h after hatching). Culturing Artemia for 48 h after hatching, in artificial sea water prepared by municipal wastewater effluent resulted to significant alterations of the isoenzyme profile. In comparison to organisms cultured for the same period of time in artificial sea water prepared by filtered tap water, the expression of the alkaline isoenzyme decreased by 62% while that of the neutral isoenzyme increased by 58%. Furthermore, the enzyme activity of the major isoenzyme of the acidic area increased by more than two folds. It is worth mentioning that although the specific activity of the total enzyme in the whole body homogenate was elevated, no statistically significant alteration of the Km value was observed. These findings suggest that study of the isoenzyme profile of Glutathione S-transferase may offer high sensitivity in detecting environmental pollution and needs to be further investigated. PMID:21429555

  4. Effects of surface-engineered nanoparticle-based dispersants for marine oil spills on the model organism Artemia franciscana.

    PubMed

    Rodd, April L; Creighton, Megan A; Vaslet, Charles A; Rangel-Mendez, J Rene; Hurt, Robert H; Kane, Agnes B

    2014-06-01

    Fine particles are under active consideration as alternatives to chemical dispersants for large-scale petroleum spills. Fine carbon particles with engineered surface chemistry have been shown to stabilize oil-in-water emulsions, but the environmental impacts of large-scale particle introduction to the marine environment are unknown. Here we study the impact of surface-engineered carbon-black materials on brine shrimp (Artemia franciscana) as a model marine microcrustacean. Mortality was characterized at 50-1000 mg/L, and levels of heat shock protein 70 (hsp70) were characterized at sublethal particle concentrations (25-50 mg/L). Functionalized carbon black (CB) nanoparticles were found to be nontoxic at all concentrations, while hydrophobic (annealed) and as-produced CB induced adverse effects at high concentrations. CB was also shown to adsorb benzene, a model hydrocarbon representing the more soluble and toxic low-molecular weight aromatic fraction of petroleum, but the extent of adsorption was insufficient to mitigate benzene toxicity to Artemia in coexposure experiments. At lower benzene concentrations (25-75 mg/L), coexposure with annealed and as-produced CB increased hsp70 protein levels. This study suggests that surface functionalization for increased hydrophilicity can not only improve the performance of CB-based dispersants but also reduce their adverse environmental impacts on marine organisms. PMID:24823274

  5. A note on the biogeographical origin of the brine shrimp Artemia urmiana Günther, 1899 from Urmia Lake, Iran.

    PubMed

    Eimanifar, Amin; Asem, Alireza; Djamali, Morteza; Wink, Michael

    2016-01-01

    The brine shrimp Artemia urmiana, an abundant inhabitant of the hypersaline Urmia Lake in northwestern Iran, has recently been described from Lake Koyashskoe, also a shallow hypersaline lake that is located on the Black Sea coast of the Crimean Peninsula (Ukraine). This discovery has questioned the endemicity of A. urmiana in Urmia Lake and has also brought into question the biogeographical origin of this species. In the present study, we combined recent genetic divergence data (mtDNA-COI) with palaeoecological evidence to address the biogeographical origin of A. urmiana. Calibration of the molecular clock of the COI region was set by assigning the age of the micro-crustacean Daphnia pulex minimally at 145 Mya. The divergence age of A. urmiana in Urmia Lake dates back to 383,000 years, whereas Ukrainian Artemia reflects a very young populations that diverged about 196,000 years ago. Palaeoecological evidence suggests that the age of the major habitat of A. urmiana i.e. Urmia Lake goes back to the Tertiary Period while the Ukranian habitats of the species are very young, by virtue of geological features of the Holocene age. We conclude that the biogeographical origin of A. urmiana is outside of Europe and the current state of knowledge strongly suggests that Urmia Lake has been the major source of its expansion into its modern habitats in Europe. PMID:27394547

  6. Effects of surface-engineered nanoparticle-based dispersants for marine oil spills on the model organism Artemia franciscana.

    PubMed

    Rodd, April L; Creighton, Megan A; Vaslet, Charles A; Rangel-Mendez, J Rene; Hurt, Robert H; Kane, Agnes B

    2014-06-01

    Fine particles are under active consideration as alternatives to chemical dispersants for large-scale petroleum spills. Fine carbon particles with engineered surface chemistry have been shown to stabilize oil-in-water emulsions, but the environmental impacts of large-scale particle introduction to the marine environment are unknown. Here we study the impact of surface-engineered carbon-black materials on brine shrimp (Artemia franciscana) as a model marine microcrustacean. Mortality was characterized at 50-1000 mg/L, and levels of heat shock protein 70 (hsp70) were characterized at sublethal particle concentrations (25-50 mg/L). Functionalized carbon black (CB) nanoparticles were found to be nontoxic at all concentrations, while hydrophobic (annealed) and as-produced CB induced adverse effects at high concentrations. CB was also shown to adsorb benzene, a model hydrocarbon representing the more soluble and toxic low-molecular weight aromatic fraction of petroleum, but the extent of adsorption was insufficient to mitigate benzene toxicity to Artemia in coexposure experiments. At lower benzene concentrations (25-75 mg/L), coexposure with annealed and as-produced CB increased hsp70 protein levels. This study suggests that surface functionalization for increased hydrophilicity can not only improve the performance of CB-based dispersants but also reduce their adverse environmental impacts on marine organisms.

  7. Probing the phenomenon of trained immunity in invertebrates during a transgenerational study, using brine shrimp Artemia as a model system.

    PubMed

    Norouzitallab, Parisa; Baruah, Kartik; Biswas, Priyanka; Vanrompay, Daisy; Bossier, Peter

    2016-01-01

    The invertebrate's innate immune system was reported to show some form of adaptive features, termed trained immunity. However, the memory characteristics of innate immune system and the mechanisms behind such phenomena remain unclear. Using the invertebrate model Artemia, we verified the possibility or impossibility of trained immunity, examining the presence or absence of enduring memory against homologous and heterologous antigens (Vibrio spp.) during a transgenerational study. We also determined the mechanisms behind such phenomenon. Our results showed the occurrence of memory and partial discrimination in Artemia's immune system, as manifested by increased resistance, for three successive generations, of the progenies of Vibrio-exposed ancestors towards a homologous bacterial strain, rather than to a heterologous strain. This increased resistance phenotype was associated with elevated levels of hsp70 and hmgb1 signaling molecules and alteration in the expression of key innate immunity-related genes. Our results also showed stochastic pattern in the acetylation and methylation levels of H4 and H3K4me3 histones, respectively, in the progenies whose ancestors were challenged. Overall results suggest that innate immune responses in invertebrates have the capacity to be trained, and epigenetic reprogramming of (selected) innate immune effectors is likely to have central place in the mechanisms leading to trained immunity. PMID:26876951

  8. Group 1 LEA proteins contribute to the desiccation and freeze tolerance of Artemia franciscana embryos during diapause.

    PubMed

    Toxopeus, Jantina; Warner, Alden H; MacRae, Thomas H

    2014-11-01

    Water loss either by desiccation or freezing causes multiple forms of cellular damage. The encysted embryos (cysts) of the crustacean Artemia franciscana have several molecular mechanisms to enable anhydrobiosis-life without water-during diapause. To better understand how cysts survive reduced hydration, group 1 late embryogenesis abundant (LEA) proteins, hydrophilic unstructured proteins that accumulate in the stress-tolerant cysts of A. franciscana, were knocked down using RNA interference (RNAi). Embryos lacking group 1 LEA proteins showed significantly lower survival than control embryos after desiccation and freezing, or freezing alone, demonstrating a role for group 1 LEA proteins in A. franciscana tolerance of low water conditions. In contrast, regardless of group 1 LEA protein presence, cysts responded similarly to hydrogen peroxide (H2O2) exposure, indicating little to no function for these proteins in diapause termination. This is the first in vivo study of group 1 LEA proteins in an animal and it contributes to the fundamental understanding of these proteins. Knowing how LEA proteins protect A. franciscana cysts from desiccation and freezing may have applied significance in aquaculture, where Artemia is an important feed source, and in the cryopreservation of cells for therapeutic applications. PMID:24846336

  9. Behavior of Settling Marine Larvae in Flow

    NASA Astrophysics Data System (ADS)

    Hernandez, J.; Koehl, M. A.

    2012-12-01

    Many bottom-dwelling marine animals produce microscopic larvae that are dispersed by ambient water currents. These larvae can only recruit to habitats on which they have landed if they can resist being washed away by ambient water flow. We found that larvae on marine surfaces do not experience steady water flow, but rather are exposed to brief pulses of water movement as turbulent eddies sweep across them. We made video recordings of larvae of the tube worm, Hydroides elegans, (important members of the community of organisms growing on docks and ships) on surfaces subjected to measured realistic flow pulses to study factors that might affect their dislodgement from surfaces in nature. We found that the response of a larva of H. elegans to a realistic pulse of water flow depended on its behavior at the time of the pulse and on its recent history of exposure to flow pulses, and that stationary larvae were less likely than locomoting larvae to be blown away when hit by the first pulse of water flow.; ;

  10. Directional flow sensing by passively stable larvae.

    PubMed

    Fuchs, Heidi L; Christman, Adam J; Gerbi, Gregory P; Hunter, Elias J; Diez, F Javier

    2015-09-01

    Mollusk larvae have a stable, velum-up orientation that may influence how they sense and react to hydrodynamic signals applied in different directions. Directional sensing abilities and responses could affect how a larva interacts with anisotropic fluid motions, including those in feeding currents and in boundary layers encountered during settlement. Oyster larvae (Crassostrea virginica) were exposed to simple shear in a Couette device and to solid-body rotation in a single rotating cylinder. Both devices were operated in two different orientations, one with the axis of rotation parallel to the gravity vector, and one with the axis perpendicular. Larvae and flow were observed simultaneously with near-infrared particle-image velocimetry, and behavior was quantified as a response to strain rate, vorticity and centripetal acceleration. Only flows rotating about a horizontal axis elicited the diving response observed previously for oyster larvae in turbulence. The results provide strong evidence that the turbulence-sensing mechanism relies on gravity-detecting organs (statocysts) rather than mechanosensors (cilia). Flow sensing with statocysts sets oyster larvae apart from zooplankters such as copepods and protists that use external mechanosensors in sensing spatial velocity gradients generated by prey or predators. Sensing flow-induced changes in orientation, rather than flow deformation, would enable more efficient control of vertical movements. Statocysts provide larvae with a mechanism of maintaining their upward swimming when rotated by vortices and initiating dives toward the seabed in response to the strong turbulence associated with adult habitats. PMID:26333930

  11. Directional flow sensing by passively stable larvae.

    PubMed

    Fuchs, Heidi L; Christman, Adam J; Gerbi, Gregory P; Hunter, Elias J; Diez, F Javier

    2015-09-01

    Mollusk larvae have a stable, velum-up orientation that may influence how they sense and react to hydrodynamic signals applied in different directions. Directional sensing abilities and responses could affect how a larva interacts with anisotropic fluid motions, including those in feeding currents and in boundary layers encountered during settlement. Oyster larvae (Crassostrea virginica) were exposed to simple shear in a Couette device and to solid-body rotation in a single rotating cylinder. Both devices were operated in two different orientations, one with the axis of rotation parallel to the gravity vector, and one with the axis perpendicular. Larvae and flow were observed simultaneously with near-infrared particle-image velocimetry, and behavior was quantified as a response to strain rate, vorticity and centripetal acceleration. Only flows rotating about a horizontal axis elicited the diving response observed previously for oyster larvae in turbulence. The results provide strong evidence that the turbulence-sensing mechanism relies on gravity-detecting organs (statocysts) rather than mechanosensors (cilia). Flow sensing with statocysts sets oyster larvae apart from zooplankters such as copepods and protists that use external mechanosensors in sensing spatial velocity gradients generated by prey or predators. Sensing flow-induced changes in orientation, rather than flow deformation, would enable more efficient control of vertical movements. Statocysts provide larvae with a mechanism of maintaining their upward swimming when rotated by vortices and initiating dives toward the seabed in response to the strong turbulence associated with adult habitats.

  12. Oxaloacetate and malate production in engineered Escherichia coli by expression of codon-optimized phosphoenolpyruvate carboxylase2 gene from Dunaliella salina.

    PubMed

    Park, Soohyun; Chang, Kwang Suk; Jin, Eonseon; Pack, Seung Pil; Lee, Jinwon

    2013-01-01

    A new phosphoenolpyruvate carboxylase (PEPC) gene of Dunaliella salina is identified using homology analysis was conducted using PEPC gene of Chlamydomonas reinhardtii and Arabidopsis thaliana. Recombinant E. coli SGJS115 with increased production of malate and oxaloacetate was developed by introducing codon-optimized phosphoenolpyruvate carboxylase2 (OPDSPEPC2) gene of Dunaliella salina. E. coli SGJS115 yielded a 9.9 % increase in malate production. In addition, E. coli SGJS115 exhibited two times increase in the yield of oxaloacetate over the E. coli SGJS114 having identified PEPC2 gene obtained from Dunaliella salina.

  13. Antioxidant and cytotoxic activity of carotenes produced by Dunaliella salina under stress.

    PubMed

    Singh, Pritika; Baranwal, Manoj; Reddy, Sudhakara M

    2016-10-01

    Context Dunaliella salina Teodoresco (Dunaliellaceae) is one of the promising microalgae consumed as food and medicine for many years. Objective Dunaliella salina was grown under different stress conditions for enhancing carotene production. The carotene enriched extract was evaluated for antioxidant and cytotoxic activity. Materials and methods Carotene content was calculated under salinity, nitrogen and temperature stress conditions. Antioxidant activity was determined through DPPH assay by incubating the samples for 45 min with 250 μg/mL of extract and reducing power assay was performed with 50, 100, 150 and 200 μg/mL of extract. Cytotoxicity was determined by incubating ∼2 × 10(4) MCF-7 (breast cancer) cells with 250 μg of extract in each well for 72 h by MTT assay. Result Carotene content was significantly increased to 9.8 (3.5 M NaCl), 13.9 (37 °C), 8.2 (250 mM KNO3) and 10.6 μg/mL (nitrogen-depleted medium) as compared with 3.2 μg/mL in normal conditions (1.7 M NaCl, 0.75 mM KNO3 and 28 °C). Free radical scavenging activity increased at 3.0 and 3.5 M NaCl (27.8 and 57.5%, respectively), 37 °C (31.4%) and in nitrogen-depleted medium (41.9%) compared with normal (15%) conditions. Carotene content and scavenging activity were positively correlated under salinity (r = 0.97), temperature (r = 0.85) and nitrogen (r = 0.7) stress conditions. Cytotoxicity against MCF-7 cell lines increased due to increase in carotene content suggesting that cytotoxicity may be associated with carotene accumulation. Discussion and conclusions Carotene content enhanced by D. salina under stress conditions increased the antioxidant and cytotoxic activity. PMID:26983781

  14. Antioxidant and cytotoxic activity of carotenes produced by Dunaliella salina under stress.

    PubMed

    Singh, Pritika; Baranwal, Manoj; Reddy, Sudhakara M

    2016-10-01

    Context Dunaliella salina Teodoresco (Dunaliellaceae) is one of the promising microalgae consumed as food and medicine for many years. Objective Dunaliella salina was grown under different stress conditions for enhancing carotene production. The carotene enriched extract was evaluated for antioxidant and cytotoxic activity. Materials and methods Carotene content was calculated under salinity, nitrogen and temperature stress conditions. Antioxidant activity was determined through DPPH assay by incubating the samples for 45 min with 250 μg/mL of extract and reducing power assay was performed with 50, 100, 150 and 200 μg/mL of extract. Cytotoxicity was determined by incubating ∼2 × 10(4) MCF-7 (breast cancer) cells with 250 μg of extract in each well for 72 h by MTT assay. Result Carotene content was significantly increased to 9.8 (3.5 M NaCl), 13.9 (37 °C), 8.2 (250 mM KNO3) and 10.6 μg/mL (nitrogen-depleted medium) as compared with 3.2 μg/mL in normal conditions (1.7 M NaCl, 0.75 mM KNO3 and 28 °C). Free radical scavenging activity increased at 3.0 and 3.5 M NaCl (27.8 and 57.5%, respectively), 37 °C (31.4%) and in nitrogen-depleted medium (41.9%) compared with normal (15%) conditions. Carotene content and scavenging activity were positively correlated under salinity (r = 0.97), temperature (r = 0.85) and nitrogen (r = 0.7) stress conditions. Cytotoxicity against MCF-7 cell lines increased due to increase in carotene content suggesting that cytotoxicity may be associated with carotene accumulation. Discussion and conclusions Carotene content enhanced by D. salina under stress conditions increased the antioxidant and cytotoxic activity.

  15. A first AFLP-Based Genetic Linkage Map for Brine Shrimp Artemia franciscana and Its Application in Mapping the Sex Locus

    PubMed Central

    De Vos, Stephanie; Bossier, Peter; Van Stappen, Gilbert; Vercauteren, Ilse; Sorgeloos, Patrick; Vuylsteke, Marnik

    2013-01-01

    We report on the construction of sex-specific linkage maps, the identification of sex-linked markers and the genome size estimation for the brine shrimp Artemia franciscana. Overall, from the analysis of 433 AFLP markers segregating in a 112 full-sib family we identified 21 male and 22 female linkage groups (2n = 42), covering 1,041 and 1,313 cM respectively. Fifteen putatively homologous linkage groups, including the sex linkage groups, were identified between the female and male linkage map. Eight sex-linked AFLP marker alleles were inherited from the female parent, supporting the hypothesis of a WZ–ZZ sex-determining system. The haploid Artemia genome size was estimated to 0.93 Gb by flow cytometry. The produced Artemia linkage maps provide the basis for further fine mapping and exploring of the sex-determining region and are a possible marker resource for mapping genomic loci underlying phenotypic differences among Artemia species. PMID:23469207

  16. Preparation of chitosan from brine shrimp (Artemia urmiana) cyst shells and effects of different chemical processing sequences on the physicochemical and functional properties of the product.

    PubMed

    Tajik, Hossein; Moradi, Mehran; Rohani, Seyed Mehdi Razavi; Erfani, Amir Mehdi; Jalali, Farnood Shokouhi Sabet

    2008-06-06

    Chitosan (CS) was prepared from Artemia urmiana cyst shells using the same chemical process as described for the other crustacean species, with minor adjustments in the treatment conditions. The influence of modifications of the CS production process on the physiochemical and functional properties of the CS obtained was examined. The study results indicate that Artemia urmiana cyst shells are a rich source of chitin as 29.3-34.5% of the shell's dry weight consisted of this material. Compared to crab CS (selected as an example of CS from a different crustacean source) Artemia CS exhibited a medium molecular weight (4.5-5.7 x10(5) Da), lower degree of deacetylation (67-74%) and lower viscosity (29-91 centiposes). The physicochemical characteristics (e.g., ash, nitrogen and molecular weight) and functional properties (e.g., water binding capacity and antibacterial activity) of the prepared Artemia CSs were enhanced, compared to control and commercial samples, by varying the processing step sequence.

  17. Cutaneous Larva Migrans in Early Infancy

    PubMed Central

    Siddalingappa, Karjigi; Murthy, Sambasiviah Chidambara; Herakal, Kallappa; Kusuma, Marganahalli Ramachandra

    2015-01-01

    Cutaneous larva migrans or creeping eruptions is a cutaneous dermatosis caused by hookworm larvae, Ancylostoma braziliense. A 2-month-old female child presented with a progressive rash over the left buttock of 4 days duration. Cutaneous examination showed an urticarial papule progressing to erythematous, tortuous, thread-like tract extending a few centimeters from papule over the left gluteal region. A clinical diagnosis of cutaneous larva migrans was considered. Treatment with albendazole led to complete resolution, confirming the diagnosis. This is to the best of our knowledge, the youngest age at which this condition is being reported. PMID:26538729

  18. Detrimental effect of CO2-driven seawater acidification on a crustacean brine shrimp, Artemia sinica.

    PubMed

    Zheng, Chao-qun; Jeswin, Joseph; Shen, Kai-li; Lablche, Meghan; Wang, Ke-jian; Liu, Hai-peng

    2015-03-01

    The effects of the decline in ocean pH, termed as ocean acidification due to the elevated carbon dioxide in the atmosphere, on calcifying organisms such as marine crustacean are unclear. To understand the possible effects of ocean acidification on the physiological responses of a marine model crustacean brine shrimp, Artemia sinica, three groups of the cysts or animals were raised at different pH levels (8.2 as control; 7.8 and 7.6 as acidification stress according to the predictions for the end of this century and next century accordingly) for 24 h or two weeks, respectively, followed by examination of their hatching success, morphological appearance such as deformity and microstructure of animal body, growth (i.e. body length), survival rate, expression of selected genes (involved in development, immunity and cellular activity etc), and biological activity of several key enzymes (participated in antioxidant responses and physiological reactions etc). Our results clearly demonstrated that the cysts hatching rate, growth at late stage of acidification stress, and animal survival rate of brine shrimp were all reduced due to lower pH level (7.6 & 7.8) on comparison to the control group (pH 8.2), but no obvious change in deformity or microstructure of brine shrimp was present under these acidification stress by microscopy observation and section analysis. In addition, the animals subjected to a lower pH level of seawater underwent changes on their gene expressions, including Spätzle, MyD88, Notch, Gram-negative bacteria binding protein, prophenoloxidase, Apoptosis inhibitor 5, Trachealess, Caveolin-1 and Cyclin K. Meanwhile, several key enzyme activities, including superoxide dismutase, catalase, peroxidase, alkaline phosphatase and acid phosphatase, were also affected by acidified seawater stress. Taken together, our findings supports the idea that CO2-driven seawater acidification indeed has a detrimental effect, in case of hatching success, growth and survival, on

  19. Effects of copper, cadmium, and zinc on the hatching success of brine shrimp (Artemia franciscana).

    PubMed

    Brix, K V; Gerdes, R M; Adams, W J; Grosell, M

    2006-11-01

    Previous studies indicate that the hatching success of brine shrimp (Artemia franciscana) cysts is surprisingly sensitive to ambient metal concentrations. These studies estimated median effective concentrations (EC50s) of 7, 5, and 28 microg l-1 for Cd, Cu, and Zn, suggesting that the hatching end point for A. franciscana is the most sensitive tested to date for Cd and Zn in saline environments and comparable in sensitivity with the most sensitive tested to date for Cu. Furthermore, these data suggest that brine shrimp are at significant risk from Cu and Zn in Great Salt Lake (GSL), UT, where ambient concentrations as high as 10 and 14 microg l-1, respectively, have been measured. Given that brine shrimp appear to be successfully reproducing in GSL, we hypothesized that these toxicity values were either biased low as a result of an artifact of the test method used or that site-specific water-quality conditions in the lake had decreased metal bioavailability such that brine shrimp could successfully reproduce. To test these hypotheses, we initiated a step-wise series of experiments. First we investigated the effects of pretreatment of brine shrimp cysts with antibiotics on brine shrimp sensitivity to metals because previous investigators as part of their test methods have used antibiotics. Next we considered the effect of ionic composition of the artificial test media on sensitivity. Finally, we evaluated the effects of the site-specific water quality of the GSL on metal bioavailability and toxicity. Results indicate that pretreatment of cysts with antibiotics had no effect on sensitivity. However, we were unable to repeat the previous values for Cd and Zn, obtaining EC50s of 11,859 and 289 microg l-1 for Cd and Zn, respectively. For Cu, however, we estimated an EC50 of 12 microg l-1, so we conducted further testing on the artificial media, adjusting the media composition to better reflect the Ca2+ and HCO3- concentration of normal seawater. This increased the EC50

  20. Quiescence in Artemia franciscana embryos: reversible arrest of metabolism and gene expression at low oxygen levels.

    PubMed

    Hand, S C

    1998-04-01

    Depression of the production and consumption of cellular energy appears to be a prerequisite for the survival of prolonged bouts of anoxia. A correlation exists between the degree of metabolic depression under anoxia and the duration of anoxia tolerance. In the case of brine shrimp (Artemia franciscana) embryos, oxygen deprivation induces a reversible quiescent state that can be tolerated for several years with substantial survivorship. A global arrest of cytoplasmic translation accompanies the transition into anoxia, and rates of protein synthesis in mitochondria from these embryos appears to be markedly reduced in response to anoxia. Previous evidence suggests that the acute acidification of intracellular pH (pHi) by over 1.0 unit during the transition into anoxia contributes to the depression of biosynthesis, but message limitation does not appear to play a role in the down-regulation in either cellular compartment. The ontogenetic increase in mRNA levels for a mitochondrial-encoded subunit of cytochrome c oxidase (COX I) and for nuclear-encoded actin is blocked by anoxia and aerobic acidosis (artificial quiescence imposed by intracellular acidification under aerobic conditions). Further, the levels of COX I and actin mRNA do not decline appreciably during 6 h bouts of quiescence, even though protein synthesis is acutely arrested across this same period. Thus, the constancy of mRNA levels during quiescence indicates that reduced protein synthesis is not caused by message limitation but, instead, is probably controlled at the translational level. This apparent stabilization of mRNA under anoxia is mirrored in an extension of protein half-life. The ubiquitin-dependent pathway for protein degradation is depressed under anoxia and aerobic acidosis, as judged by the acute drop in levels of ubiquitin-conjugated proteins. Mitochondrial protein synthesis is responsive to both acidification of pHi and removal of oxygen per se. Matrix pH declines in parallel with pHi, and

  1. Transcriptional initiation under conditions of anoxia-induced quiescence in mitochondria from Artemia franciscana embryos.

    PubMed

    Eads, Brian D; Hand, Steven C

    2003-02-01

    In response to anoxia, embryos of the brine shrimp Artemia franciscana are able coordinately to downregulate metabolism to levels low enough to permit survival for several years at room temperature. In addition to dramatic decreases in free ATP levels and heat production, intracellular pH drops from 7.8 to 6.3 overnight. Use of isolated mitochondria to study transcriptional responses to anoxia offers several advantages: (1). the localized nature of transcript initiation, processing and degradation, all of which may be followed in organello; (2). the relatively simple cis- and trans-machinery involved and (3). the ability to provide relevant physiological treatments in vitro. In response to anoxic incubation of embryos in vivo for 4 h followed by anoxic mitochondrial isolation and anoxic transcription assay at pH 6.4, a significant decrease in overall UTP incorporation (77%) was seen after 30 min relative to normoxic, pH 7.9 controls. A less severe inhibition of transcription under anoxia (52%) was observed compared with controls when pH was raised to 7.9. Similarly, under normoxia, the incubation at low pH (6.4) reduced transcription by 59%. Ribonuclease protection assays showed that the contribution of in vitro initiation during the assay fell from 78% at pH 7.9 to approximately 32% at pH 6.4 under either normoxic or anoxic conditions. DNA footprinting of putative transcriptional promoters revealed proteins at regular intervals upstream of the 12S rRNA in the control region, which previously had been indirectly inferred to contain promoters for H-strand transcription. The area between 1230 and 12065 contains a sequence in the tRNA(leu) gene believed to bind the transcription termination factor mTERF or TERM, and we provide the first evidence that this sequence is protein-bound in A. franciscana. However, our hypothesis that initiation is reduced at low pH because of a change in DNA binding by mitochondrial transcription factors was not confirmed. We propose that

  2. Development of direct conversion method for microalgal biodiesel production using wet biomass of Nannochloropsis salina.

    PubMed

    Kim, Tae-Hyoung; Suh, William I; Yoo, Gursong; Mishra, Sanjiv K; Farooq, Wasif; Moon, Myounghoon; Shrivastav, Anupama; Park, Min S; Yang, Ji-Won

    2015-09-01

    In this work, the effects of several factors, such as temperature, reaction time, and solvent and acid quantity on in situ transesterification yield of wet Nannochloropsis salina were investigated. Under equivalent total solvent volume to biomass ratio, pure alcohol showed higher yield compared to alcohol-chloroform solvent. For esterifying 200 mg of wet cells, 2 ml of methanol and 1 ml of ethanol was sufficient to complete in situ transesterification. Under temperatures of 105 °C or higher, 2.5% and 5% concentrations of sulfuric acid was able to successfully convert more than 90% of lipid within 30 min when methanol and ethanol was used as solvents respectively. Also, it was verified that the optimal condition found in small-scale experiments is applicable to larger scale using 2 L scale reactor as well. PMID:25827362

  3. Altered lipid accumulation in Nannochloropsis salina CCAP849/3 following EMS and UV induced mutagenesis

    PubMed Central

    Beacham, T.A.; Macia, V. Mora; Rooks, P.; White, D.A.; Ali, S.T.

    2015-01-01

    Microalgae have potential as a chemical feed stock in a range of industrial applications. Nannochloropsis salina was subject to EMS mutagenesis and the highest lipid containing cells selected using fluorescence-activated cell sorting. Assessment of growth, lipid content and fatty acid composition identified mutant strains displaying a range of altered traits including changes in the PUFA content and a total FAME increase of up to 156% that of the wild type strain. Combined with a reduction in growth this demonstrated a productivity increase of up to 76%. Following UV mutagenesis, lipid accumulation of the mutant cultures was elevated to more than 3 fold that of the wild type strain, however reduced growth rates resulted in a reduction in overall productivity. Changes observed are indicative of alterations to the regulation of the omega 6 Kennedy pathway. The importance of these variations in physiology for industrial applications such as biofuel production is discussed. PMID:26753128

  4. Assessment of benthic changes during 20 years of monitoring the Mexican Salina Cruz Bay.

    PubMed

    González-Macías, C; Schifter, I; Lluch-Cota, D B; Méndez-Rodríguez, L; Hernández-Vázquez, S

    2009-02-01

    In this work a non-parametric multivariate analysis was used to assess the impact of metals and organic compounds in the macro infaunal component of the mollusks benthic community using surface sediment data from several monitoring programs collected over 20 years in Salina Cruz Bay, Mexico. The data for benthic mollusks community characteristics (richness, abundance and diversity) were linked to multivariate environmental patterns, using the Alternating Conditional Expectations method to correlate the biological measurements of the mollusk community with the physicochemical properties of water and sediments. Mollusks community variation is related to environmental characteristics as well as lead content. Surface deposit feeders are increasing their relative density, while subsurface deposit feeders are decreasing with respect to time, these last are expected to be more related with sediment and more affected then by its quality. However gastropods with predatory carnivore as well as chemosymbiotic deposit feeder bivalves have maintained their relative densities along time.

  5. Assessment of carotenoid production by Dunaliella salina in different culture systems and operation regimes.

    PubMed

    Prieto, Ana; Pedro Cañavate, J; García-González, Mercedes

    2011-01-20

    The effect of operation regime and culture system on carotenoid productivity by the halotolerant alga Dunaliella salina has been analyzed. Operation strategies tested included batch and semi continuous regime, as well as a two-stage approach run simultaneously in both, open tanks and closed reactor. The best results were obtained with the closed tubular photobioreactor. The highest carotenoid production (328.8 mg carotenoid l⁻¹ culture per month) was achieved with this culture system operated following the two-stage strategy. Also, closed tubular photobioreactor provided the highest carotenoid contents (10% of dry weight) in Dunaliella biomass and β-carotene abundance (90% of total carotenoids) as well as the highest 9-cis to all-trans β-carotene isomer ratio (1.5 at sunrise).

  6. Lethal infection thresholds of Paenibacillus larvae for honeybee drone and worker larvae (Apis mellifera).

    PubMed

    Behrens, Dieter; Forsgren, Eva; Fries, Ingemar; Moritz, Robin F A

    2010-10-01

    We compared the mortality of honeybee (Apis mellifera) drone and worker larvae from a single queen under controlled in vitro conditions following infection with Paenibacillus larvae, a bacterium causing the brood disease American Foulbrood (AFB). We also determined absolute P. larvae cell numbers and lethal titres in deceased individuals of both sexes up to 8 days post infection using quantitative real-time PCR (qPCR). Our results show that in drones the onset of infection induced mortality is delayed by 1 day, the cumulative mortality is reduced by 10% and P. larvae cell numbers are higher than in worker larvae. Since differences in bacterial cell titres between sexes can be explained by differences in body size, larval size appears to be a key parameter for a lethal threshold in AFB tolerance. Both means and variances for lethal thresholds are similar for drone and worker larvae suggesting that drone resistance phenotypes resemble those of related workers.

  7. Lethal infection thresholds of Paenibacillus larvae for honeybee drone and worker larvae (Apis mellifera).

    PubMed

    Behrens, Dieter; Forsgren, Eva; Fries, Ingemar; Moritz, Robin F A

    2010-10-01

    We compared the mortality of honeybee (Apis mellifera) drone and worker larvae from a single queen under controlled in vitro conditions following infection with Paenibacillus larvae, a bacterium causing the brood disease American Foulbrood (AFB). We also determined absolute P. larvae cell numbers and lethal titres in deceased individuals of both sexes up to 8 days post infection using quantitative real-time PCR (qPCR). Our results show that in drones the onset of infection induced mortality is delayed by 1 day, the cumulative mortality is reduced by 10% and P. larvae cell numbers are higher than in worker larvae. Since differences in bacterial cell titres between sexes can be explained by differences in body size, larval size appears to be a key parameter for a lethal threshold in AFB tolerance. Both means and variances for lethal thresholds are similar for drone and worker larvae suggesting that drone resistance phenotypes resemble those of related workers. PMID:20545737

  8. TIME management by medicinal larvae.

    PubMed

    Pritchard, David I; Čeřovský, Václav; Nigam, Yamni; Pickles, Samantha F; Cazander, Gwendolyn; Nibbering, Peter H; Bültemann, Anke; Jung, Wilhelm

    2016-08-01

    Wound bed preparation (WBP) is an integral part of the care programme for chronic wounds. The acronym TIME is used in the context of WBP and describes four barriers to healing in chronic wounds; namely, dead Tissue, Infection and inflammation, Moisture imbalance and a non-migrating Edge. Larval debridement therapy (LDT) stems from observations that larvae of the blowfly Lucilia sericata clean wounds of debris. Subsequent clinical studies have proven debriding efficacy, which is likely to occur as a result of enzymatically active alimentary products released by the insect. The antimicrobial, anti-inflammatory and wound healing activities of LDT have also been investigated, predominantly in a pre-clinical context. This review summarises the findings of investigations into the molecular mechanisms of LDT and places these in context with the clinical concept of WBP and TIME. It is clear from these findings that biotherapy with L. sericata conforms with TIME, through the enzymatic removal of dead tissue and its associated biofilm, coupled with the secretion of defined antimicrobial peptides. This biotherapeutic impact on the wound serves to reduce inflammation, with an associated capacity for an indirect effect on moisture imbalance. Furthermore, larval serine proteinases have the capacity to alter fibroblast behaviour in a manner conducive to the formation of granulation tissue.

  9. Analysis of the Physiological and Molecular Responses of Dunaliella salina to Macronutrient Deprivation.

    PubMed

    Lv, Hexin; Cui, Xianggan; Wahid, Fazli; Xia, Feng; Zhong, Cheng; Jia, Shiru

    2016-01-01

    The halotolerant chlorophyte Dunaliella salina can accumulate up to 10% of its dry weight as β-carotene in chloroplasts when subjected to adverse conditions, including nutrient deprivation. However, the mechanisms of carotenoid biosynthesis are poorly understood. Here, the physiological and molecular responses to the deprivation of nitrogen (-N), sulfur (-S), phosphorus (-P) and different combinations of those nutrients (-N-P, -N-S, -P-S and -N-P-S) were compared to gain insights into the underlying regulatory mechanisms of carotenoid biosynthesis. The results showed that both the growth and photosynthetic rates of cells were decreased during nutrient deprivation, accompanied by lipid globule accumulation and reduced chlorophyll levels. The SOD and CAT activities of the cells were altered during nutrient deprivation, but their responses were different. The total carotenoid contents of cells subjected to multiple nutrient deprivation were higher than those of cells subjected to single nutrient deprivation and non-stressed cells. The β-carotene contents of cells subjected to -N-P, -N-S and -N-P-S were higher than those of cells subjected to single nutrient deprivation. Cells subjected to sulfur deprivation accumulated more lutein than cells subjected to nitrogen and phosphorous deprivation. In contrast, no cumulative effects of nutrient deprivation on the transcription of genes in the carotenogenic pathway were observed because MEP and carotenogenic pathway genes were up-regulated during single nutrient deprivation but were downregulated during multiple nutrient deprivation. Therefore, we proposed that the carotenoid biosynthesis pathway of D. salina is regulated at both the transcriptional and posttranscriptional levels and that a complex crosstalk occurs at the physiological and molecular levels in response to the deprivation of different nutrients. PMID:27023397

  10. Analysis of the Physiological and Molecular Responses of Dunaliella salina to Macronutrient Deprivation.

    PubMed

    Lv, Hexin; Cui, Xianggan; Wahid, Fazli; Xia, Feng; Zhong, Cheng; Jia, Shiru

    2016-01-01

    The halotolerant chlorophyte Dunaliella salina can accumulate up to 10% of its dry weight as β-carotene in chloroplasts when subjected to adverse conditions, including nutrient deprivation. However, the mechanisms of carotenoid biosynthesis are poorly understood. Here, the physiological and molecular responses to the deprivation of nitrogen (-N), sulfur (-S), phosphorus (-P) and different combinations of those nutrients (-N-P, -N-S, -P-S and -N-P-S) were compared to gain insights into the underlying regulatory mechanisms of carotenoid biosynthesis. The results showed that both the growth and photosynthetic rates of cells were decreased during nutrient deprivation, accompanied by lipid globule accumulation and reduced chlorophyll levels. The SOD and CAT activities of the cells were altered during nutrient deprivation, but their responses were different. The total carotenoid contents of cells subjected to multiple nutrient deprivation were higher than those of cells subjected to single nutrient deprivation and non-stressed cells. The β-carotene contents of cells subjected to -N-P, -N-S and -N-P-S were higher than those of cells subjected to single nutrient deprivation. Cells subjected to sulfur deprivation accumulated more lutein than cells subjected to nitrogen and phosphorous deprivation. In contrast, no cumulative effects of nutrient deprivation on the transcription of genes in the carotenogenic pathway were observed because MEP and carotenogenic pathway genes were up-regulated during single nutrient deprivation but were downregulated during multiple nutrient deprivation. Therefore, we proposed that the carotenoid biosynthesis pathway of D. salina is regulated at both the transcriptional and posttranscriptional levels and that a complex crosstalk occurs at the physiological and molecular levels in response to the deprivation of different nutrients.

  11. Analysis of the Physiological and Molecular Responses of Dunaliella salina to Macronutrient Deprivation

    PubMed Central

    Lv, Hexin; Cui, Xianggan; Wahid, Fazli; Xia, Feng; Zhong, Cheng; Jia, Shiru

    2016-01-01

    The halotolerant chlorophyte Dunaliella salina can accumulate up to 10% of its dry weight as β-carotene in chloroplasts when subjected to adverse conditions, including nutrient deprivation. However, the mechanisms of carotenoid biosynthesis are poorly understood. Here, the physiological and molecular responses to the deprivation of nitrogen (-N), sulfur (-S), phosphorus (-P) and different combinations of those nutrients (-N-P, -N-S, -P-S and -N-P-S) were compared to gain insights into the underlying regulatory mechanisms of carotenoid biosynthesis. The results showed that both the growth and photosynthetic rates of cells were decreased during nutrient deprivation, accompanied by lipid globule accumulation and reduced chlorophyll levels. The SOD and CAT activities of the cells were altered during nutrient deprivation, but their responses were different. The total carotenoid contents of cells subjected to multiple nutrient deprivation were higher than those of cells subjected to single nutrient deprivation and non-stressed cells. The β-carotene contents of cells subjected to -N-P, -N-S and -N-P-S were higher than those of cells subjected to single nutrient deprivation. Cells subjected to sulfur deprivation accumulated more lutein than cells subjected to nitrogen and phosphorous deprivation. In contrast, no cumulative effects of nutrient deprivation on the transcription of genes in the carotenogenic pathway were observed because MEP and carotenogenic pathway genes were up-regulated during single nutrient deprivation but were downregulated during multiple nutrient deprivation. Therefore, we proposed that the carotenoid biosynthesis pathway of D. salina is regulated at both the transcriptional and posttranscriptional levels and that a complex crosstalk occurs at the physiological and molecular levels in response to the deprivation of different nutrients. PMID:27023397

  12. Zebrafish fed on recombinant Artemia expressing epinecidin-1 exhibit increased survival and altered expression of immunomodulatory genes upon Vibrio vulnificus infection.

    PubMed

    Jheng, Yu-Hsuan; Lee, Lin-Han; Ting, Chen-Hung; Pan, Chieh-Yu; Hui, Cho-Fat; Chen, Jyh-Yih

    2015-01-01

    Artemia has been used extensively in aquaculture as fodder for larval fish, shrimp, and shellfish. Epinecidin-1, an antimicrobial peptide, was isolated from grouper (Epinephelus coioides) in 2005. Epinecidin-1 has been previously reported to possess antimicrobial activity against several Gram-positive and Gram-negative bacterial species, including Staphylococcus coagulase, Pseudomonas aeruginosa, Streptococcus pyogenes, and Vibrio vulnificus. In this study, we used electroporation to introduce plasmid DNA encoding a green fluorescent protein (EGFP)-epinecidin-1 fusion protein under the control of the cytomegalovirus (CMV) promoter into decapsulated Artemia cysts. Optimization of various properties (including cyst weight (0.2 g), plasmid concentration (50 μg/100 μl), and pulse voltage (150 V), length (10 ms), and number (2)) resulted in a hatching rate of 41.15%, a transfection efficiency of 49.81%, and a fluorescence intensity (A.U.) of 47.46. The expression of EGFP-epinecidin-1 was first detected by quantitative RT-PCR at 120 h post-electroporation, and protein was identified by Western blot at the same time. Furthermore, the EGFP-epinecidin-1 protein inhibited V. vulnificus (204) growth, as demonstrated by zone of inhibition studies. Zebrafish fed on transgenic Artemia expressing CMV-gfp-epi combined with commercial fodder were more resistant to infection by V. vulnificus (204): survival rate was enhanced by over 70% at 7, 14, and 21 days post-infection, and bacterial numbers in the liver and intestine were reduced. In addition, feeding of transgenic Artemia to zebrafish affected the immunomodulatory response to V. vulnificus (204) infection; expression of immune-responsive genes, including hepcidin and defbl2, was altered, as shown by qPCR. These findings suggest that feeding transgenic Artemia expressing CMV-gfp-epi to larval fish has antimicrobial effects, without the drawbacks of introducing drug residues or inducing bacterial drug resistance.

  13. Comparison of pH-dependent allostery and dissociation for phosphofructokinases from Artemia embryos and rabbit muscle: nature of the enzymes acylated with diethylpyrocarbonate.

    PubMed

    Carpenter, J F; Hand, S C

    1986-07-01

    Purified Artemia phosphofructokinase (PFK), unlike the rabbit skeletal muscle enzyme, displays allosteric kinetics at pH 8, a feature that is functionally significant since the intracellular pH of the developing brine shrimp embryo is greater than or equal to 7.9. Catalytic activity of the Artemia enzyme is severely suppressed by acidic pH even when assayed at the adenylate nucleotide concentrations existing in anaerobic embryos, which is consistent with the lack of a Pasteur effect in these organisms. For both PFK homologs, carbethoxylation reduces the sensitivity to ATP and citrate inhibition, the cooperativity as a function of fructose 6-phosphate concentration and the degree of activation in the presence ADP, AMP, and fructose 2,6-bisphosphate. Considering the role of histidine protonation in PFK allosteric control, the capacity for regulatory kinetics seen at pH 8 in the Artemia enzyme could be explained in part by upward shifts in pKa values of ionizable residues. pH-induced dissociation of tetrameric Artemia PFK into inactive subunits does not occur during catalytic inhibition at acidic pH (pH 6.5, 6 degrees C), as judged by 90 degree light scattering. This observation contrasts markedly with the dimerization and inactivation of rabbit PFK, but is shown not to be unique when compared to other selected PFK homologs. Neither the acute pH sensitivity of Artemia PFK nor the pH-induced hysteretic inactivation displayed by the rabbit enzyme are altered by carbethoxylation, suggesting that ionizable residues involved in these two processes are not the same ones involved in allosteric kinetics. PMID:2942107

  14. First evidence of fish larvae producing sounds

    PubMed Central

    Staaterman, Erica; Paris, Claire B.; Kough, Andrew S.

    2014-01-01

    The acoustic ecology of marine fishes has traditionally focused on adults, while overlooking the early life-history stages. Here, we document the first acoustic recordings of pre-settlement stage grey snapper larvae (Lutjanus griseus). Through a combination of in situ and unprovoked laboratory recordings, we found that L. griseus larvae are acoustically active during the night, producing ‘knock’ and ‘growl’ sounds that are spectrally and temporally similar to those of adults. While the exact function and physiological mechanisms of sound production in fish larvae are unknown, we suggest that these sounds may enable snapper larvae to maintain group cohesion at night when visual cues are reduced. PMID:25274018

  15. What's eating you? Cutaneous larva migrans.

    PubMed

    Prickett, Kyle A; Ferringer, Tammie C

    2015-03-01

    This article provides a focused update and clinical review on cutaneous larva migrans (CLM), including atypical clinical presentations and newer management recommendations. The results and recommendations are subject to modification based on future studies.

  16. Activity of R(+) Limonene Against Anisakis Larvae

    PubMed Central

    Muscolino, Daniele; Panebianco, Felice; Patania, Andrea; Benianti, Chiara; Ziino, Graziella; Giuffrida, Alessandro

    2015-01-01

    The aim of this work is to evaluate the activity of R(+) limonene of against Anisakidae larvae. Its effectiveness was tested in vitro. The results obtained showed a significant activity of the compound against Anisakis larvae, suggesting further investigation on its potential use in the industrial marinating process. In this regard, the use of R(+) limonene in seafood products could be interesting, also due the sensory attributes resulting from its use and its relatively safe status. PMID:27800423

  17. Bioflocculation of the oceanic microalga Dunaliella salina by the bloom-forming dinoflagellate Heterocapsa circularisquama, and its effect on biodiesel properties of the biomass.

    PubMed

    Cho, Kichul; Hur, Sung-Pyo; Lee, Chi-Heon; Ko, Kyungjun; Lee, Yeon-Ji; Kim, Kil-Nam; Kim, Moo-Sang; Chung, Young-Ho; Kim, Daekyung; Oda, Tatsuya

    2016-02-01

    The aim of this work was to evaluate the flocculation by the dinoflagellate Heterocapsa circularisquama as a means for harvesting three Chlorophyta species, Chlorella vulgaris, Nannochloropsis granulata, and Dunaliella salina. Relative fluorescence of D. salina culture significantly decreased along with 9.3-fold increased flocculation activity within 24 h when mixed with H. circularisquama. Lipid content of bioflocculated D. salina increased about 40%, while fatty acid methyl ester (FAME) profiles exhibited higher levels of C16:0, C18:0, and C18:1, compared to harvest by centrifugation, suggesting higher energy content. Furthermore, bioflocculated D. salina biomass had more suitable biodiesel properties relative to both EN14214 and ASTMD6751, with a cetane number of 49.0 and an iodine value of 95.9. These results suggest that H. circularisquama-induced bioflocculation is applicable for the sustainable and qualitative production of algal biodiesel.

  18. Bioflocculation of the oceanic microalga Dunaliella salina by the bloom-forming dinoflagellate Heterocapsa circularisquama, and its effect on biodiesel properties of the biomass.

    PubMed

    Cho, Kichul; Hur, Sung-Pyo; Lee, Chi-Heon; Ko, Kyungjun; Lee, Yeon-Ji; Kim, Kil-Nam; Kim, Moo-Sang; Chung, Young-Ho; Kim, Daekyung; Oda, Tatsuya

    2016-02-01

    The aim of this work was to evaluate the flocculation by the dinoflagellate Heterocapsa circularisquama as a means for harvesting three Chlorophyta species, Chlorella vulgaris, Nannochloropsis granulata, and Dunaliella salina. Relative fluorescence of D. salina culture significantly decreased along with 9.3-fold increased flocculation activity within 24 h when mixed with H. circularisquama. Lipid content of bioflocculated D. salina increased about 40%, while fatty acid methyl ester (FAME) profiles exhibited higher levels of C16:0, C18:0, and C18:1, compared to harvest by centrifugation, suggesting higher energy content. Furthermore, bioflocculated D. salina biomass had more suitable biodiesel properties relative to both EN14214 and ASTMD6751, with a cetane number of 49.0 and an iodine value of 95.9. These results suggest that H. circularisquama-induced bioflocculation is applicable for the sustainable and qualitative production of algal biodiesel. PMID:26733439

  19. Coral Larvae Move toward Reef Sounds

    PubMed Central

    Vermeij, Mark J. A.; Marhaver, Kristen L.; Huijbers, Chantal M.; Nagelkerken, Ivan; Simpson, Stephen D.

    2010-01-01

    Free-swimming larvae of tropical corals go through a critical life-phase when they return from the open ocean to select a suitable settlement substrate. During the planktonic phase of their life cycle, the behaviours of small coral larvae (<1 mm) that influence settlement success are difficult to observe in situ and are therefore largely unknown. Here, we show that coral larvae respond to acoustic cues that may facilitate detection of habitat from large distances and from upcurrent of preferred settlement locations. Using in situ choice chambers, we found that settling coral larvae were attracted to reef sounds, produced mainly by fish and crustaceans, which we broadcast underwater using loudspeakers. Our discovery that coral larvae can detect and respond to sound is the first description of an auditory response in the invertebrate phylum Cnidaria, which includes jellyfish, anemones, and hydroids as well as corals. If, like settlement-stage reef fish and crustaceans, coral larvae use reef noise as a cue for orientation, the alleviation of noise pollution in the marine environment may gain further urgency. PMID:20498831

  20. Coral larvae move toward reef sounds.

    PubMed

    Vermeij, Mark J A; Marhaver, Kristen L; Huijbers, Chantal M; Nagelkerken, Ivan; Simpson, Stephen D

    2010-01-01

    Free-swimming larvae of tropical corals go through a critical life-phase when they return from the open ocean to select a suitable settlement substrate. During the planktonic phase of their life cycle, the behaviours of small coral larvae (<1 mm) that influence settlement success are difficult to observe in situ and are therefore largely unknown. Here, we show that coral larvae respond to acoustic cues that may facilitate detection of habitat from large distances and from upcurrent of preferred settlement locations. Using in situ choice chambers, we found that settling coral larvae were attracted to reef sounds, produced mainly by fish and crustaceans, which we broadcast underwater using loudspeakers. Our discovery that coral larvae can detect and respond to sound is the first description of an auditory response in the invertebrate phylum Cnidaria, which includes jellyfish, anemones, and hydroids as well as corals. If, like settlement-stage reef fish and crustaceans, coral larvae use reef noise as a cue for orientation, the alleviation of noise pollution in the marine environment may gain further urgency. PMID:20498831

  1. The carotenogenesis pathway via the isoprenoid-beta-carotene interference approach in a new strain of Dunaliella salina isolated from Baja California Mexico.

    PubMed

    Paniagua-Michel, J; Capa-Robles, Willian; Olmos-Soto, Jorge; Gutierrez-Millan, Luis Enrique

    2009-01-01

    D. salina is one of the recognized natural sources to produce beta-carotene, and an useful model for studying the role of inhibitors and enhancers of carotenogenesis. However there is little information in D. salina regarding whether the isoprenoid substrate can be influenced by stress factors (carotenogenic) or selective inhibitors which in turn may further contribute to elucidate the early steps of carotenogenesis and biosynthesis of beta-carotene. In this study, Dunaliella salina (BC02) isolated from La Salina BC Mexico, was subjected to the method of isoprenoids-beta-carotene interference in order to promote the interruption or accumulation of the programmed biosynthesis of carotenoids. When Carotenogenic and non-carotenogenic cells of D. salina BC02 were grown under photoautotrophic growth conditions in the presence of 200 microM fosmidomycin, carotenogenesis and the synthesis of beta-carotene were interrupted after two days in cultured D. salina cells. This result is an indirect consequence of the inhibition of the synthesis of isoprenoids and activity of the recombinant DXR enzyme thereby preventing the conversion of 1-deoxy-D-xylulose 5-phosphate (DXP) to 2-C-methyl-D-erythritol (MEP) and consequently interrupts the early steps of carotenogenesis in D. salina. The effect at the level of proteins and RNA was not evident. Mevinolin treated D. salina cells exhibited carotenogenesis and beta-carotene levels very similar to those of control cell cultures indicating that mevinolin not pursued any indirect action in the biosynthesis of isoprenoids and had no effect at the level of the HMG-CoA reductase, the key enzyme of the Ac/MVA pathway.

  2. Lethal and sublethal endpoints observed for Artemia exposed to two reference toxicants and an ecotoxicological concern organic compound.

    PubMed

    Manfra, Loredana; Canepa, Sara; Piazza, Veronica; Faimali, Marco

    2016-01-01

    Swimming speed alteration and mortality assays with the marine crustacean Artemia franciscana were carried out. EC50 and LC50 values after 24-48h exposures were calculated for two reference toxicants, copper sulphate pentahydrate (CuSO4·5H2O) and Sodium Dodecyl Sulphate (SDS), and an ecotoxicological concern organic compound, Diethylene Glycol (DEG). Different end-points have been evaluated, in order to point out their sensitivity levels. The swimming speed alteration (SSA) was compared to mortality values and also to the hatching rate inhibition (literature data). SSA resulted to be more sensitive than the mortality and with a sensitivity comparable to (or even higher than) the hatching rate endpoint. PMID:26344887

  3. Effect of specific light supply rate on photosynthetic efficiency of Nannochloropsis salina in a continuous flat plate photobioreactor.

    PubMed

    Sforza, Eleonora; Calvaruso, Claudio; Meneghesso, Andrea; Morosinotto, Tomas; Bertucco, Alberto

    2015-10-01

    In this work, Nannochloropsis salina was cultivated in a continuous-flow flat-plate photobioreactor, working at different residence times and irradiations to study the effect of the specific light supply rate on biomass productivity and photosynthetic efficiency. Changes in residence times lead to different steady-state cell concentrations and specific growth rates. We observed that cultures at steady concentration were exposed to different values of light intensity per cell. This specific light supply rate was shown to affect the photosynthetic status of the cells, monitored by fluorescence measurements. High specific light supply rate can lead to saturation and photoinhibition phenomena if the biomass concentration is not optimized for the selected operating conditions. Energy balances were applied to quantify the biomass growth yield and maintenance requirements in N. salina cells. PMID:26257264

  4. Effect of specific light supply rate on photosynthetic efficiency of Nannochloropsis salina in a continuous flat plate photobioreactor.

    PubMed

    Sforza, Eleonora; Calvaruso, Claudio; Meneghesso, Andrea; Morosinotto, Tomas; Bertucco, Alberto

    2015-10-01

    In this work, Nannochloropsis salina was cultivated in a continuous-flow flat-plate photobioreactor, working at different residence times and irradiations to study the effect of the specific light supply rate on biomass productivity and photosynthetic efficiency. Changes in residence times lead to different steady-state cell concentrations and specific growth rates. We observed that cultures at steady concentration were exposed to different values of light intensity per cell. This specific light supply rate was shown to affect the photosynthetic status of the cells, monitored by fluorescence measurements. High specific light supply rate can lead to saturation and photoinhibition phenomena if the biomass concentration is not optimized for the selected operating conditions. Energy balances were applied to quantify the biomass growth yield and maintenance requirements in N. salina cells.

  5. Screening of a protein that interacts with the matrix attachment region-binding protein from Dunaliella salina.

    PubMed

    Yang, Rui; Li, Zhaoxi; Lin, Yan; Yang, Baosheng; Wang, Tianyun

    2013-01-01

    We isolated the matrix attachment region-binding protein (MBP) DMBP-1 from Dunaliella salina in our previous studies. MBPs are part of the cis-acting protein family cluster. The regulatory function possibly works through the interaction of the MBPs with each other. In the present study, DMBP-1 was used as the bait in screening the D. salina cDNA library for DMBP-1 interactors that could potentially mediate the DMBP-1-regulated functions. A novel MBP, namely, DMBP-2, was identified as a DMBP-1 binding partner. The cDNA of DMBP-1 was 823 bp long and contained a 573 bp open reading frame, which encoded a polypeptide of 191 amino acids. The interaction between DMBP-2 and DMBP-1 was further confirmed through glutathione S-transferase pull-down assays.

  6. Transcriptional response of honey bee larvae infected with the bacterial pathogen Paenibacillus larvae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    American foulbrood disease of honey bees is caused by the bacterium Paenibacillus larvae. Infection occurs per os in larvae and systemic infection requires a breaching of the host peritrophic matrix and midgut epithelium. Genetic variation exists for both bacterial virulence and host resistance, and...

  7. Centrifugal partition extraction of β-carotene from Dunaliella salina for efficient and biocompatible recovery of metabolites.

    PubMed

    Marchal, Luc; Mojaat-Guemir, Mariem; Foucault, Alain; Pruvost, Jérémy

    2013-04-01

    A biocompatible extraction method for β-carotene recovery from the microalga Dunaliella salina was studied. The centrifugal partition extraction was used for liquid-liquid mass transfer intensification during continuous extraction. Different solvents and process parameters were compared. Ethyl oleate extraction with 5% dichloromethane achieved a 65% β-carotene recovery with the least amount of cell damage as more than 65% of the cells remained viable as demonstrated by photosynthesis activity measurements.

  8. Colorimetric Evaluation of the Viability of the Microalga Dunaliella Salina as a Test Tool for Nanomaterial Toxicity.

    PubMed

    Golubev, Alexander A; Prilepskii, Artur Y; Dykman, Lev A; Khlebtsov, Nikolai G; Bogatyrev, Vladimir A

    2016-05-01

    A diagnostic test system was developed to determine the toxicity of nanomaterials to the saltwater microalga Dunaliella salina through evaluation of cell death and changes in the culture growth rate at various toxicant concentrations, providing LC50 and other toxicological metrics. The viability of cells was shown to decrease with decreasing chlorophyll absorption of red light by damaged cells. This correlation was confirmed by independent fluorescence microscopic measurements of live and dead cells in the population. Two standard colorless pollutants, hydrogen peroxide and formaldehyde, were used to validate the colorimetric method. The method's performance is exemplified with three Ag-containing preparations (Ag nitrate, Ag proteinate, and 20-nm Ag nanoparticles) and with cetyltrimethylammonium bromide (CTAB) mixed with colloidal 15-nm Au and 20-nm Ag nanoparticles. The toxicity of the Ag-containing preparations to D. salina decreased in the order Ag nitrate ≥ Ag proteinate ≫ colloidal Ag. The toxicity of colloidal Au-CTAB mixtures was found to depend mostly on the content of free CTAB. The toxicity of colloidal Ag increased substantially in the presence of CTAB. The results suggest that our D. salina-based colorimetric test system can be used for simple and rapid preliminary screening of the toxicity of different nanomaterials.

  9. Effect of Ca2+ channel block on glycerol metabolism in Dunaliella salina under hypoosmotic and hyperosmotic stresses.

    PubMed

    Chen, Hui; Chen, Shan-Li; Jiang, Jian-Guo

    2011-01-01

    The effect of Ca(2+) channel blockers on cytosolic Ca(2+) levels and the role of Ca(2+) in glycerol metabolism of Dunaliella salina under hypoosmotic or hyperosmotic stress were investigated using the confocal laser scanning microscope (CLSM). Results showed that intracellular Ca(2+) concentration increased rapidly when extracellular salinity suddenly decreased or increased, but the increase could be inhibited by pretreatment of Ca(2+) channel blockers LaCl(3), verapamil or ruthenium red. The changes of glycerol content and G3pdh activity in D. salina to respect to hypoosmotic or hyperosmotic stress were also inhibited in different degrees by pretreatment of Ca(2+) channel blockers, indicating that the influx of Ca(2+) via Ca(2+) channels are required for the transduction of osmotic signal to regulate osmotic responses of D. salina to the changes of salinity. Differences of the three blockers in block effect suggested that they may act on different channels or had different action sites, including influx of Ca(2+) from the extracellular space via Ca(2+) channels localized in the plasma membrane or from intracellular calcium store via the mitochondrial. Other Ca(2+)-mediated or non-Ca(2+)-mediated osmotic signal pathway may exist in Dunaliella in response to hypoosmotic and hyperosmotic stresses.

  10. Construction of rice site-specific chloroplast transformation vector and transient expression of EGFP gene in Dunaliella salina.

    PubMed

    Li, Ding; Han, Xiaoxia; Zuo, Jia; Xie, Lingling; He, Ronghua; Gao, Jing; Chang, Lan; Yuan, Longping; Cao, Mengliang

    2011-12-01

    Chloroplast is a new hotspot in the field of plant transformation system of plant genetic engineering. Plastid transformation has several advantages: high expression, multiple expressed genes in a single transformation event, absence of gene silencing, et al. A series of elements for construction of dicistronic site-specific integration expression vector of rice chloroplast have been cloned, including trnl-trnA (rice chloroplast homologous recombination fragments), Prrn (16S rRNA operon promotor), PpsbA (the 3' untranslated region of the chloroplastpsbA gene), hptll gene (encoding hygromycin phosphotransferase) and EGFP (encoding enhanced green fluorescence protein). All the elements were constructed into a rice chloroplast dicistronic expression vector pCTE04 (-trnl-Prrn-RBS-hptlI-RBS-EGFP-PpsbA- trnA-). Then pCTE04 was introduced into chloroplasts of Dunaliella salina through particle bombardment. Strong green fluorescence was observed in chloroplasts of some bombarded Dunaliella salina cells under a stereo fluorescence microscope, indicating that pCTE04 could be expressed in Dunaliella salina chloroplasts transiently. It provides a solid foundation for further genetic engineering in rice chloroplast transformation.

  11. Thermal maturation and petroleum source rocks in Forest City and Salina basins, mid-continent, U. S. A

    SciTech Connect

    Newell, K.D.; Watney, W.L.; Hatch, J.R.; Xiaozhong, G.

    1986-05-01

    Shales in the Middle Ordovician Simpson Group are probably the source rocks for a geochemically distinct group of lower pristane and low phytane oils produced along the axis of the Forest City basin, a shallow cratonic Paleozoic basin. These oils, termed Ordovician-type oils, occur in some fields in the southern portion of the adjacent Salina basin. Maturation modeling by time-temperature index (TTI) calculations indicate that maturation of both basins was minimal during the early Paleozoic. The rate of maturation significantly increased during the Pennsylvanian because of rapid regional subsidence in response to the downwarping of the nearby Anadarko basin. When estimated thicknesses of eroded Pennsylvanian, Permian, and Cretaceous strata are considered, both basins remain relatively shallow, with maximum basement burial probably not exceeding 2 km. According to maturation modeling and regional structure mapping, the axes of both basins should contain Simpson rocks in the early stages of oil generation. The probability of finding commercial accumulations of Ordovician-type oil along the northwest-southeast trending axis of the Salina basin will decrease in a northwestward direction because of (1) westward thinning of the Simpson Group, and (2) lesser maturation due to lower geothermal gradients and shallower paleoburial depths. The optimum localities for finding fields of Ordovician-type oil in the southern Salina basin will be in down-plunge closures on anticlines that have drainage areas near the basin axis.

  12. Quantifying and predicting Drosophila larvae crawling phenotypes.

    PubMed

    Günther, Maximilian N; Nettesheim, Guilherme; Shubeita, George T

    2016-01-01

    The fruit fly Drosophila melanogaster is a widely used model for cell biology, development, disease, and neuroscience. The fly's power as a genetic model for disease and neuroscience can be augmented by a quantitative description of its behavior. Here we show that we can accurately account for the complex and unique crawling patterns exhibited by individual Drosophila larvae using a small set of four parameters obtained from the trajectories of a few crawling larvae. The values of these parameters change for larvae from different genetic mutants, as we demonstrate for fly models of Alzheimer's disease and the Fragile X syndrome, allowing applications such as genetic or drug screens. Using the quantitative model of larval crawling developed here we use the mutant-specific parameters to robustly simulate larval crawling, which allows estimating the feasibility of laborious experimental assays and aids in their design. PMID:27323901

  13. Quantifying and predicting Drosophila larvae crawling phenotypes

    PubMed Central

    Günther, Maximilian N.; Nettesheim, Guilherme; Shubeita, George T.

    2016-01-01

    The fruit fly Drosophila melanogaster is a widely used model for cell biology, development, disease, and neuroscience. The fly’s power as a genetic model for disease and neuroscience can be augmented by a quantitative description of its behavior. Here we show that we can accurately account for the complex and unique crawling patterns exhibited by individual Drosophila larvae using a small set of four parameters obtained from the trajectories of a few crawling larvae. The values of these parameters change for larvae from different genetic mutants, as we demonstrate for fly models of Alzheimer’s disease and the Fragile X syndrome, allowing applications such as genetic or drug screens. Using the quantitative model of larval crawling developed here we use the mutant-specific parameters to robustly simulate larval crawling, which allows estimating the feasibility of laborious experimental assays and aids in their design. PMID:27323901

  14. Sensorimotor structure of Drosophila larva phototaxis

    PubMed Central

    Kane, Elizabeth A.; Gershow, Marc; Afonso, Bruno; Larderet, Ivan; Klein, Mason; Carter, Ashley R.; de Bivort, Benjamin L.; Sprecher, Simon G.; Samuel, Aravinthan D. T.

    2013-01-01

    The avoidance of light by fly larvae is a classic paradigm for sensorimotor behavior. Here, we use behavioral assays and video microscopy to quantify the sensorimotor structure of phototaxis using the Drosophila larva. Larval locomotion is composed of sequences of runs (periods of forward movement) that are interrupted by abrupt turns, during which the larva pauses and sweeps its head back and forth, probing local light information to determine the direction of the successive run. All phototactic responses are mediated by the same set of sensorimotor transformations that require temporal processing of sensory inputs. Through functional imaging and genetic inactivation of specific neurons downstream of the sensory periphery, we have begun to map these sensorimotor circuits into the larval central brain. We find that specific sensorimotor pathways that govern distinct light-evoked responses begin to segregate at the first relay after the photosensory neurons. PMID:24043822

  15. Expressed sequence tag (EST) profiling in hyper saline shocked Dunaliella salina reveals high expression of protein synthetic apparatus components.

    PubMed

    Alkayal, Fadi; Albion, Rebecca L; Tillett, Richard L; Hathwaik, Leyla T; Lemos, Mark S; Cushman, John C

    2010-11-01

    The unicellular, halotolerant, green alga, Dunaliella salina (Chlorophyceae) has the unique ability to adapt and grow in a wide range of salt conditions from about 0.05 to 5.5M. To better understand the molecular basis of its salinity tolerance, a complementary DNA (cDNA) library was constructed from D. salina cells adapted to 2.5M NaCl, salt-shocked at 3.4M NaCl for 5h, and used to generate an expressed sequence tag (EST) database. ESTs were obtained for 2831 clones representing 1401 unique transcripts. Putative functions were assigned to 1901 (67.2%) ESTs after comparison with protein databases. An additional 154 (5.4%) ESTs had significant similarity to known sequences whose functions are unclear and 776 (27.4%) had no similarity to known sequences. For those D. salina ESTs for which functional assignments could be made, the largest functional categories included protein synthesis (35.7%), energy (photosynthesis) (21.4%), primary metabolism (13.8%) and protein fate (6.8%). Within the protein synthesis category, the vast majority of ESTs (80.3%) encoded ribosomal proteins representing about 95% of the approximately 82 subunits of the cytosolic ribosome indicating that D. salina invests substantial resources in the production and maintenance of protein synthesis. The increased mRNA expression upon salinity shock was verified for a small set of selected genes by real-time, quantitative reverse-transcription-polymerase chain reaction (qRT-PCR). This EST collection also provided important new insights into the genetic underpinnings for the biosynthesis and utilization of glycerol and other osmoprotectants, the carotenoid biosynthetic pathway, reactive oxygen-scavenging enzymes, and molecular chaperones (heat shock proteins) not described previously for D. salina. EST discovery also revealed the existence of RNA interference and signaling pathways associated with osmotic stress adaptation. The unknown ESTs described here provide a rich resource for the identification

  16. Physiological characteristics and stress resistance of great sturgeon (Huso huso) juveniles fed with vitamins C, E, and HUFA-enriched Artemia urmiana nauplii.

    PubMed

    Jalali, Mohammad Ali; Hosseini, Seyed Abbas; Imanpour, Mohammad Reza

    2010-09-01

    This study was carried out to examine the effect of Artemia urmiana nauplii enriched with HUFA, and vitamins C and E on stress tolerance, hematocrit, and biochemical parameters of great sturgeon, Huso huso juveniles. Cod liver oil (EPA 18% and DHA 12%), ascorbyl-6-palmitate and alpha-tocopherol acetate were used as lipid, and vitamin C and E sources, respectively. Beluga juveniles at the stage of first feeding (69.7 +/- 5.9 mg body weight) were randomly divided into five treatments and three tanks were assigned to each diet. All fish groups were fed non-enriched Artemia for the initial 5 days and then fed enriched Artemia for 7 days. Juveniles were fed with Artemia enriched with HUFA + 20% vitamin C (C group); HUFA + 20% vitamin E-enriched Artemia nauplii (E group); HUFA + 20% vitamin C + 20% vitamin E (C and E group); HUFA without vitamins (HUFA) and non-enriched Artemia (control). After the period of enrichment, Juveniles were fed with Daphnia sp. from the 13th to the 40th day. At day 40, the fish were transferred directly from fresh water (0.5 ppt) to brackish water (6 ppt for 4 days and 12 ppt for 2 days) and warm water (from 27 to 33 degrees C) to evaluate juvenile resistance to salinity and thermal shocks. Moreover, all treatments were separately exposed to freshwater in tanks with the same capacity as used for osmotic and thermal tests (as fresh water control). The addition of vitamins C, E, and C + E to HUFA significantly increased fish resistance to 12 ppt salinity and temperature stress tests, whereas survival was not significantly different among challenges at 6 ppt. There was no significant difference in the hematocrit index under stress conditions. Enrichment had significant influence on plasma Na(+) level in the C group on the 4th day at 6 ppt. Na(+) and Ca(2+) concentrations in C, E, and C and E groups on the 1st day at 12 ppt, and Ca(2+) level in E group on the 2nd day at 12 ppt were lower than the other groups. The glucose level in the C and C and

  17. Physiological characteristics and stress resistance of great sturgeon (Huso huso) juveniles fed with vitamins C, E, and HUFA-enriched Artemia urmiana nauplii.

    PubMed

    Jalali, Mohammad Ali; Hosseini, Seyed Abbas; Imanpour, Mohammad Reza

    2010-09-01

    This study was carried out to examine the effect of Artemia urmiana nauplii enriched with HUFA, and vitamins C and E on stress tolerance, hematocrit, and biochemical parameters of great sturgeon, Huso huso juveniles. Cod liver oil (EPA 18% and DHA 12%), ascorbyl-6-palmitate and alpha-tocopherol acetate were used as lipid, and vitamin C and E sources, respectively. Beluga juveniles at the stage of first feeding (69.7 +/- 5.9 mg body weight) were randomly divided into five treatments and three tanks were assigned to each diet. All fish groups were fed non-enriched Artemia for the initial 5 days and then fed enriched Artemia for 7 days. Juveniles were fed with Artemia enriched with HUFA + 20% vitamin C (C group); HUFA + 20% vitamin E-enriched Artemia nauplii (E group); HUFA + 20% vitamin C + 20% vitamin E (C and E group); HUFA without vitamins (HUFA) and non-enriched Artemia (control). After the period of enrichment, Juveniles were fed with Daphnia sp. from the 13th to the 40th day. At day 40, the fish were transferred directly from fresh water (0.5 ppt) to brackish water (6 ppt for 4 days and 12 ppt for 2 days) and warm water (from 27 to 33 degrees C) to evaluate juvenile resistance to salinity and thermal shocks. Moreover, all treatments were separately exposed to freshwater in tanks with the same capacity as used for osmotic and thermal tests (as fresh water control). The addition of vitamins C, E, and C + E to HUFA significantly increased fish resistance to 12 ppt salinity and temperature stress tests, whereas survival was not significantly different among challenges at 6 ppt. There was no significant difference in the hematocrit index under stress conditions. Enrichment had significant influence on plasma Na(+) level in the C group on the 4th day at 6 ppt. Na(+) and Ca(2+) concentrations in C, E, and C and E groups on the 1st day at 12 ppt, and Ca(2+) level in E group on the 2nd day at 12 ppt were lower than the other groups. The glucose level in the C and C and

  18. Predators induce cloning in echinoderm larvae.

    PubMed

    Vaughn, Dawn; Strathmann, Richard R

    2008-03-14

    Asexual propagation (cloning) is a widespread reproductive strategy of plants and animals. Although larval cloning is well documented in echinoderms, identified stimuli for cloning are limited to those associated with conditions favorable for growth and reproduction. Our research shows that larvae of the sand dollar Dendraster excentricus also clone in response to cues from predators. Predator-induced clones were smaller than uncloned larvae, suggesting an advantage against visual predators. Our results offer another ecological context for asexual reproduction: rapid size reduction as a defense.

  19. A case study to optimise and validate the brine shrimp Artemia franciscana immobilisation assay with silver nanoparticles: The role of harmonisation.

    PubMed

    Kos, Monika; Kahru, Anne; Drobne, Damjana; Singh, Shashi; Kalčíková, Gabriela; Kühnel, Dana; Rohit, Rekulapelly; Gotvajn, Andreja Žgajnar; Jemec, Anita

    2016-06-01

    Brine shrimp Artemia sp. has been recognised as an important ecotoxicity and nanotoxicity test model organism for salt-rich aquatic environments, but currently there is still no harmonised testing protocol which would ensure the comparable results for hazard identification. In this paper we aimed to design the harmonised protocol for nanomaterial toxicity testing using Artemia franciscana and present a case study to validate the protocol with silver nanoparticles (AgNPs). We (i) revised the existing nanotoxicity test protocols with Artemia sp. (ii) optimised certain methodological steps based on the experiments with AgNPs and potassium dichromate (K2Cr2O7) as a soluble reference chemical and (iii) tested the optimised protocol in an international inter-laboratory exercise conducted within the EU FP7 NanoValid project. The intra- and inter-laboratory reproducibility of the proposed protocol with a soluble reference chemical K2Cr2O7 was good, which confirms the suitability of this assay for conventional chemicals. However, the variability of AgNPs toxicity results was very high showing again that nanomaterials are inherently challenging for toxicity studies, especially those which toxic effect is linked to shed metal ions. Among the identified sources for this variability were: the hatching conditions, the type of test plate incubation and the illumination regime. The latter induced variations assumingly due to the changes in bioavailable silver species concentrations. Up to our knowledge this is the first inter-laboratory comparison of the Artemia sp. toxicity study involving nanomaterials. Although the inter-laboratory exercise revealed poor repeatability of AgNPs toxicity results, this study provides valuable information regarding the importance of harmonisation of all steps in the test procedure. Also, the presented AgNPs toxicity case study may serve as a platform for further validation steps with other types of NMs. PMID:26895539

  20. The Small Heat Shock Protein p26 Aids Development of Encysting Artemia Embryos, Prevents Spontaneous Diapause Termination and Protects against Stress

    PubMed Central

    King, Allison M.; MacRae, Thomas H.

    2012-01-01

    Artemia franciscana embryos enter diapause as encysted gastrulae, a physiological state of metabolic dormancy and enhanced stress resistance. The objective of this study was to use RNAi to investigate the function of p26, an abundant, diapause-specific small heat shock protein, in the development and behavior of encysted Artemia embryos (cysts). RNAi methodology was developed where injection of Artemia females with dsRNA specifically eliminated p26 from cysts. p26 mRNA and protein knock down were, respectively, confirmed by RT-PCR and immuno-probing of western blots. ArHsp21 and ArHsp22, diapause-related small heat shock proteins in Artemia cysts sharing a conserved α-crystallin domain with p26, were unaffected by injection of females with dsRNA for p26, demonstrating the specificity of protein knock down. Elimination of p26 delayed cyst release from females demonstrating that this molecular chaperone influences the development of diapause-destined embryos. Although development was slowed the metabolic activities of cysts either containing or lacking p26 were similar. p26 inhibited diapause termination after prolonged incubation of cysts in sea water perhaps by a direct effect on termination or indirectly because p26 is necessary for the preservation of diapause maintenance. Cyst diapause was however, terminated by desiccation and freezing, a procedure leading to high mortality within cyst populations lacking p26 and indicating the protein is required for stress tolerance. Cysts lacking p26 were also less resistant to heat shock. This is the first in vivo study to show that knock down of a small heat shock protein slows the development of diapause-destined embryos, suggesting a role for p26 in the developmental process. The same small heat shock protein prevents spontaneous termination of diapause and provides stress protection to encysted embryos. PMID:22952748

  1. PCR-identification of Dunaliella salina (Volvocales, Chlorophyta) and its growth characteristics.

    PubMed

    Raja, Rathinam; Hema Iswarya, Shanmugam; Balasubramanyam, Dakshanamoorthy; Rengasamy, Ramasamy

    2007-01-01

    The saline pond microalga, Dunaliella salina (Dunal) Teod. maintained in De Walne's (basal) medium under laboratory conditions was confirmed by amplifying the chromosomal DNA of the microalga by PCR with specific primers MA1 and MA2. Seaweed extracts obtained from Sargassum wightii and Ulva lactuca were amended separately at 1.0%, 1.5%, 2.0% and 2.5% levels to the basal medium in order to assess their potential on the growth and concentration of pigments, viz. Chl a, Chl b and beta-carotene of the alga. beta-Carotene was isolated and visible absorption spectrum was taken at 443 and 475 nm confirmed the presence of 9-cis-beta-carotene and all-trans-beta-carotene isomers. Maximum yield, highest division rate (mu) and highest pigment concentrations were observed in the cells grown in 1.5% S. wightii and 2.0% U. lactuca amended medium and these cells were subjected to DAPI staining. The results of epifluorescence microscopy and image analysis revealed a significant enhancement of the cell and nuclear area of the microalgae. PMID:16697630

  2. The Rhodomonas salina mitochondrial genome: bacteria-like operons, compact gene arrangement and complex repeat region.

    PubMed

    Hauth, Amy M; Maier, Uwe G; Lang, B Franz; Burger, Gertraud

    2005-01-01

    To gain insight into the mitochondrial genome structure and gene content of a putatively ancestral group of eukaryotes, the cryptophytes, we sequenced the complete mitochondrial DNA of Rhodomonas salina. The 48 063 bp circular-mapping molecule codes for 2 rRNAs, 27 tRNAs and 40 proteins including 23 components of oxidative phosphorylation, 15 ribosomal proteins and two subunits of tat translocase. One potential protein (ORF161) is without assigned function. Only two introns occur in the genome; both are present within cox1 belong to group II and contain RT open reading frames. Primitive genome features include bacteria-like rRNAs and tRNAs, ribosomal protein genes organized in large clusters resembling bacterial operons and the presence of the otherwise rare genes such as rps1 and tatA. The highly compact gene organization contrasts with the presence of a 4.7 kb long, repeat-containing intergenic region. Repeat motifs approximately 40-700 bp long occur up to 31 times, forming a complex repeat structure. Tandem repeats are the major arrangement but the region also includes a large, approximately 3 kb, inverted repeat and several potentially stable approximately 40-80 bp long hairpin structures. We provide evidence that the large repeat region is involved in replication and transcription initiation, predict a promoter motif that occurs in three locations and discuss two likely scenarios of how this highly structured repeat region might have evolved.

  3. Death of a carbonate basin: The Niagara-Salina transition in the Michigan basin

    SciTech Connect

    Leibold, A.W.; Howell, P.D. )

    1991-03-01

    The A-O Carbonate in the Michigan basin comprises a sequence of laminated calcite/anhydrite layers intercalated with bedded halite at the transition between normal marine Niagaran carbonates and lower Salina Group evaporites. The carbonate/anhydrite interbeds represent freshing events during initial evaporative concentration of the Michigan basin. Recent drilling in the Michigan basin delineates two distinct regions of A-O Carbonate development: a 5 to 10 m thick sequence of six 'laminites' found throughout most of the western and northern basin and a 10 to 25 m thick sequence in the southeastern basin containing both thicker 'laminates' and thicker salt interbeds. Additionally, potash deposits of the overlying A-1 evaporite unit are restricted to the northern and western basin regions. The distribution of evaporite facies in these two regions is adequately explained by a source of basin recharge in the southeast-perhaps the 'Clinton Inlet' of earlier workers. This situation suggest either that: (1) the source of basin recharge is alternately supplying preconcentrated brine and more normal marine water, or (2) that the basin received at least two distinct sources of water during A-O deposition.

  4. Effects of Light and Temperature on Fatty Acid Production in Nannochloropsis Salina

    SciTech Connect

    Van Wagenen, Jonathan M.; Miller, Tyler W.; Hobbs, Samuel J.; Hook, Paul W.; Crowe, Braden J.; Huesemann, Michael H.

    2012-03-12

    Accurate prediction of algal biofuel yield will require empirical determination of physiological responses to the climate, particularly light and temperature. One strain of interest, Nannochloropsis salina, was subjected to ranges of light intensity (5-850 {mu}mol m{sup -2} s{sup -1}) and temperature (13-40 C); exponential growth rate, total fatty acids (TFA) and fatty acid composition were measured. The maximum acclimated growth rate was 1.3 day{sup -1} at 23 C and 250 {mu}mol m{sup -2} s{sup -1}. Fatty acids were detected by gas chromatography with flame ionization detection (GC-FID) after transesterification to corresponding fatty acid methyl esters (FAME). A sharp increase in TFA containing elevated palmitic acid (C16:0) and palmitoleic acid (C16:1) during exponential growth at high light was observed, indicating likely triacylglycerol accumulation due to photo-oxidative stress. Lower light resulted in increases in the relative abundance of unsaturated fatty acids; in thin cultures, increases were observed in palmitoleic and eicosapentaenoeic acids (C20:5{omega}3). As cultures aged and the effective light intensity per cell converged to very low levels, fatty acid profiles became more similar and there was a notable increase of oleic acid (C18:1{omega}9). The amount of unsaturated fatty acids was inversely proportional to temperature, demonstrating physiological adaptations to increase membrane fluidity. This data will improve prediction of fatty acid characteristics and yields relevant to biofuel production.

  5. Determination of Ion Content and Ion Fluxes in the Halotolerant Alga Dunaliella salina

    PubMed Central

    Pick, Uri; Karni, Leah; Avron, Mordhay

    1986-01-01

    A method to determine intracellular cation contents in Dunaliella by separation on cation-exchange minicolumns is described. The separation efficiency of cells from extracellular cations is over 99.9%; the procedure causes no apparent perturbation to the cells and can be applied to measure both fluxes and internal content of any desired cation. Using this technique it is demonstrated that the intracellular averaged Na+, K+, and Ca2+ concentrations in Dunaliella salina cultured at 1 to 4 molar NaCl, 5 millimolar K+, and 0.3 millimolar Ca2+ are 20 to 100 millimolar, 150 to 250 millimolar, and 1 to 3 millimolar, respectively. The intracellular K+ concentration is maintained constant over a wide range of media K+ concentrations (0.5-10 millimolar), leading to a ratio of K+ in the cells to K+ in the medium of 10 to 1,000. Severe limitation of external K+, induces loss of K+ and increase in Na+ inside the cells. The results suggest that Dunaliella cells possess efficient mechanisms to eliminate Na+ and accumulate K+ and that intracellular Na+ and K+ concentrations are carefully regulated. The contribution of the intracellular Na+ and K+ salts to the total osmotic pressure of cells grown at 1 to 4 molar NaCl, is 5 to 20%. PMID:16664814

  6. Probing the protective mechanism of poly-ß-hydroxybutyrate against vibriosis by using gnotobiotic Artemia franciscana and Vibrio campbellii as host-pathogen model.

    PubMed

    Baruah, Kartik; Huy, Tran T; Norouzitallab, Parisa; Niu, Yufeng; Gupta, Sanjay K; De Schryver, Peter; Bossier, Peter

    2015-01-01

    The compound poly-ß-hydroxybutyrate (PHB), a polymer of the short chain fatty acid ß-hydroxybutyrate, was shown to protect experimental animals against a variety of bacterial diseases, (including vibriosis in farmed aquatic animals), albeit through undefined mechanisms. Here we aimed at unraveling the underlying mechanism behind the protective effect of PHB against bacterial disease using gnotobiotically-cultured brine shrimp Artemia franciscana and pathogenic Vibrio campbellii as host-pathogen model. The gnotobiotic model system is crucial for such studies because it eliminates any possible microbial interference (naturally present in any type of aquatic environment) in these mechanistic studies and furthermore facilitates the interpretation of the results in terms of a cause effect relationship. We showed clear evidences indicating that PHB conferred protection to Artemia host against V. campbellii by a mechanism of inducing heat shock protein (Hsp) 70. Additionally, our results also showed that this salutary effect of PHB was associated with the generation of protective innate immune responses, especially the prophenoloxidase and transglutaminase immune systems - phenomena possibly mediated by PHB-induced Hsp70. From overall results, we conclude that PHB induces Hsp70 and this induced Hsp70 might contribute in part to the protection of Artemia against pathogenic V. campbellii. PMID:25822312

  7. Comparison of Artemia-bacteria associations in brines, laboratory cultures and the gut environment: a study based on Chilean hypersaline environments.

    PubMed

    Quiroz, Mauricio; Triadó-Margarit, Xavier; Casamayor, Emilio O; Gajardo, Gonzalo

    2015-01-01

    The brine shrimp Artemia (Crustacea) and a diversity of halophilic microorganisms coexist in natural brines, salterns and laboratory cultures; part of such environmental microbial diversity is represented in the gut of Artemia individuals. Bacterial diversity in these environments was assessed by 16S rRNA gene denaturing gradient gel electrophoresis (DGGE) fingerprinting. Eight natural locations in Chile, where A. franciscana or A. persimilis occur, were sampled for analysis of free-living and gut-associated bacteria in water from nature and laboratory cultures. The highest ecological diversity (Shannon's index, H') was found in brines, it decreased in the gut of wild and laboratory animals, and in laboratory water. Significant differences in H' existed between brines and laboratory water, and between brines and gut of wild animals. The greatest similarity of bacterial community composition was between brines and the gut of field animals, suggesting a transient state of the gut microbiota. Sequences retrieved from DGGE patterns (n = 83) exhibited an average of 97.8% identity with 41 bacterial genera from the phyla Proteobacteria (55.4% of sequences match), Bacteroidetes (22.9%), Actinobacteria (16.9%) and Firmicutes (4.8%). Environment-exclusive genera distribution was seen in Sphingomonas and Paenibacillus (gut of field animals), Amaricoccus and Ornithinimicrobium (gut of laboratory animals), and Hydrogenophaga (water of laboratory cultures). The reported ecological and physiological capabilities of such bacteria can help to understand Artemia adaptation to natural and laboratory conditions. PMID:25239570

  8. Effects of genotoxicity and its consequences at the population level in sexual and asexual Artemia assessed by analysis of inter-simple sequence repeats (ISSR).

    PubMed

    Sukumaran, Sandhya; Grant, Alastair

    2013-09-18

    There is considerable evidence that genetic damage in organisms occurs in the environment as a result of exposure to genotoxins and ionising radiation, but we have limited understanding of the extent to which this results in adverse consequences at a population level. We used inter-simple sequence repeat (ISSR) markers to quantify genotoxic effects of the mutagen ethylmethane sulfonate (EMS) on a sexual (Artemia franciscana) and an asexual (Artemia parthenogenetica) species of brine shrimp. The method provides information similar to that obtained with assessment of RAPD (random amplification of polymorphic DNA) but is more robust. Genetic damage was transmitted to the F1 generation in both Artemia species, but the sexual species showed a greater degree of recovery, as shown by higher values of genomic template stability. There was a strong correlation between DNA damage and effects on individual fitness parameters: size, survival, reproduction and population growth. These effects persisted into the F2 generation in A. parthenogenetica, but in the sexual A. franciscana only effects on fecundity continued beyond the exposed generation, even though there were substantial alterations in ISSR patterns in the F1 generation. Genetic biomarkers can thus be indicative of effects at the population level, but sexually reproducing species have a considerable assimilative capacity for the effects of genotoxins. PMID:23872504

  9. Comparison of Artemia-bacteria associations in brines, laboratory cultures and the gut environment: a study based on Chilean hypersaline environments.

    PubMed

    Quiroz, Mauricio; Triadó-Margarit, Xavier; Casamayor, Emilio O; Gajardo, Gonzalo

    2015-01-01

    The brine shrimp Artemia (Crustacea) and a diversity of halophilic microorganisms coexist in natural brines, salterns and laboratory cultures; part of such environmental microbial diversity is represented in the gut of Artemia individuals. Bacterial diversity in these environments was assessed by 16S rRNA gene denaturing gradient gel electrophoresis (DGGE) fingerprinting. Eight natural locations in Chile, where A. franciscana or A. persimilis occur, were sampled for analysis of free-living and gut-associated bacteria in water from nature and laboratory cultures. The highest ecological diversity (Shannon's index, H') was found in brines, it decreased in the gut of wild and laboratory animals, and in laboratory water. Significant differences in H' existed between brines and laboratory water, and between brines and gut of wild animals. The greatest similarity of bacterial community composition was between brines and the gut of field animals, suggesting a transient state of the gut microbiota. Sequences retrieved from DGGE patterns (n = 83) exhibited an average of 97.8% identity with 41 bacterial genera from the phyla Proteobacteria (55.4% of sequences match), Bacteroidetes (22.9%), Actinobacteria (16.9%) and Firmicutes (4.8%). Environment-exclusive genera distribution was seen in Sphingomonas and Paenibacillus (gut of field animals), Amaricoccus and Ornithinimicrobium (gut of laboratory animals), and Hydrogenophaga (water of laboratory cultures). The reported ecological and physiological capabilities of such bacteria can help to understand Artemia adaptation to natural and laboratory conditions.

  10. Liquid chromatographic determination of efficacy of incorporation of trimethoprim and sulfamethoxazole in brine shrimp (Artemia spp.) used for prophylactic chemotherapy of fish.

    PubMed Central

    Nelis, H J; Léger, F; Sorgeloos, P; De leenheer, A P

    1991-01-01

    The brine shrimp Artemia, an excellent live food source in aquaculture, has been studied as a carrier to deliver selected chemotherapeutic agents to fish for prophylactic treatment of infectious diseases. To monitor the efficiency of incorporation of trimethoprim and sulfamethoxazole in Artemia franciscana, a sensitive and specific analytical method was developed. It is based on homogenization of Artemia nauplii in methanol, extraction of lipids with hexane, solid-phase cleanup on C18 cartridges, and reversed-phase liquid chromatography with detection at 210 nm. The method is sensitive (detection limit, on the order of 3 micrograms/g with a sample quantity of 30 mg [dry weight]) and reproducible (coefficients of variation, 2.2 and 1.8% for trimethoprim and sulfamethoxazole at levels of 79.6 and 257 micrograms/g of body weight, respectively). Preliminary quantitative data indicated excellent uptake and persistence of both therapeutic agents in A. franciscana, with levels of 115 micrograms/g for trimethoprim and 277 micrograms/g for sulfamethoxazole. PMID:1810182

  11. Effects of genotoxicity and its consequences at the population level in sexual and asexual Artemia assessed by analysis of inter-simple sequence repeats (ISSR).

    PubMed

    Sukumaran, Sandhya; Grant, Alastair

    2013-09-18

    There is considerable evidence that genetic damage in organisms occurs in the environment as a result of exposure to genotoxins and ionising radiation, but we have limited understanding of the extent to which this results in adverse consequences at a population level. We used inter-simple sequence repeat (ISSR) markers to quantify genotoxic effects of the mutagen ethylmethane sulfonate (EMS) on a sexual (Artemia franciscana) and an asexual (Artemia parthenogenetica) species of brine shrimp. The method provides information similar to that obtained with assessment of RAPD (random amplification of polymorphic DNA) but is more robust. Genetic damage was transmitted to the F1 generation in both Artemia species, but the sexual species showed a greater degree of recovery, as shown by higher values of genomic template stability. There was a strong correlation between DNA damage and effects on individual fitness parameters: size, survival, reproduction and population growth. These effects persisted into the F2 generation in A. parthenogenetica, but in the sexual A. franciscana only effects on fecundity continued beyond the exposed generation, even though there were substantial alterations in ISSR patterns in the F1 generation. Genetic biomarkers can thus be indicative of effects at the population level, but sexually reproducing species have a considerable assimilative capacity for the effects of genotoxins.

  12. Dietary β-glucan (MacroGard®) enhances survival of first feeding turbot (Scophthalmus maximus) larvae by altering immunity, metabolism and microbiota.

    PubMed

    Miest, Joanna J; Arndt, Carmen; Adamek, Mikolaj; Steinhagen, Dieter; Reusch, Thorsten B H

    2016-01-01

    Reflecting the natural biology of mass spawning fish aquaculture production of fish larvae is often hampered by high and unpredictable mortality rates. The present study aimed to enhance larval performance and immunity via the oral administration of an immunomodulator, β-glucan (MacroGard(®)) in turbot (Scophthalmus maximus). Rotifers (Brachionus plicatilis) were incubated with or without yeast β-1,3/1,6-glucan in form of MacroGard(®) at a concentration of 0.5 g/L. Rotifers were fed to first feeding turbot larvae once a day. From day 13 dph onwards all tanks were additionally fed untreated Artemia sp. nauplii (1 nauplius ml/L). Daily mortality was monitored and larvae were sampled at 11 and 24 dph for expression of 30 genes, microbiota analysis, trypsin activity and size measurements. Along with the feeding of β-glucan daily mortality was significantly reduced by ca. 15% and an alteration of the larval microbiota was observed. At 11 dph gene expression of trypsin and chymotrypsin was elevated in the MacroGard(®) fed fish, which resulted in heightened tryptic enzyme activity. No effect on genes encoding antioxidative proteins was observed, whilst the immune response was clearly modulated by β-glucan. At 11 dph complement component c3 was elevated whilst cytokines, antimicrobial peptides, toll like receptor 3 and heat shock protein 70 were not affected. At the later time point (24 dph) an anti-inflammatory effect in form of a down-regulation of hsp 70, tnf-α and il-1β was observed. We conclude that the administration of MacroGard(®) induced an immunomodulatory response and could be used as an effective measure to increase survival in rearing of turbot.

  13. Dietary β-glucan (MacroGard®) enhances survival of first feeding turbot (Scophthalmus maximus) larvae by altering immunity, metabolism and microbiota.

    PubMed

    Miest, Joanna J; Arndt, Carmen; Adamek, Mikolaj; Steinhagen, Dieter; Reusch, Thorsten B H

    2016-01-01

    Reflecting the natural biology of mass spawning fish aquaculture production of fish larvae is often hampered by high and unpredictable mortality rates. The present study aimed to enhance larval performance and immunity via the oral administration of an immunomodulator, β-glucan (MacroGard(®)) in turbot (Scophthalmus maximus). Rotifers (Brachionus plicatilis) were incubated with or without yeast β-1,3/1,6-glucan in form of MacroGard(®) at a concentration of 0.5 g/L. Rotifers were fed to first feeding turbot larvae once a day. From day 13 dph onwards all tanks were additionally fed untreated Artemia sp. nauplii (1 nauplius ml/L). Daily mortality was monitored and larvae were sampled at 11 and 24 dph for expression of 30 genes, microbiota analysis, trypsin activity and size measurements. Along with the feeding of β-glucan daily mortality was significantly reduced by ca. 15% and an alteration of the larval microbiota was observed. At 11 dph gene expression of trypsin and chymotrypsin was elevated in the MacroGard(®) fed fish, which resulted in heightened tryptic enzyme activity. No effect on genes encoding antioxidative proteins was observed, whilst the immune response was clearly modulated by β-glucan. At 11 dph complement component c3 was elevated whilst cytokines, antimicrobial peptides, toll like receptor 3 and heat shock protein 70 were not affected. At the later time point (24 dph) an anti-inflammatory effect in form of a down-regulation of hsp 70, tnf-α and il-1β was observed. We conclude that the administration of MacroGard(®) induced an immunomodulatory response and could be used as an effective measure to increase survival in rearing of turbot. PMID:26564474

  14. Evolution of foraging behavior in Drosophilid larvae

    NASA Astrophysics Data System (ADS)

    Rivera-Alba, Marta; Kabra, Mayank; Branson, Kristin; Mirth, Christen

    2015-03-01

    Drosophilids, like other insects, go through a larval phase before metamorphosing into adults. Larvae increase their body weight by several orders of magnitude in a few days. We therefore hypothesized that foraging behavior is under strong evolutionary pressure to best fit the larval environment. To test our hypothesis we used a multidisciplinary approach to analyze foraging behavior across species and larval stages. First, we recorded several videos of larvae foraging for each of 47 Drosophilid species. Then, using a supervised machine learning approach, we automatically annotated the video collection for the foraging sub-behaviors, including crawling, turning, head casting or burrowing. We also computed over 100 features to describe the posture and dynamics of each animal in each video frame. From these data, we fit models to the behavior of each species. The models each had the same parametric form, but differed in the exact parameters. By simulating larva behavior in virtual arenas we can infer which properties of the environments are better for each species. Comparisons between these inferred environments and the actual environments where these animals live will give us a deeper understanding about the evolution of foraging behavior in Drosophilid larvae.

  15. Suppressing bullfrog larvae with carbon dioxide

    USGS Publications Warehouse

    Gross, Jackson A.; Ray, Andrew; Sepulveda, Adam J.; Watten, Barnaby J.; Densmore, Christine L.; Layhee, Megan J.; Mark Abbey-Lambert,; ,

    2014-01-01

    Current management strategies for the control and suppression of the American Bullfrog (Lithobates catesbeianus = Rana catesbeiana Shaw) and other invasive amphibians have had minimal effect on their abundance and distribution. This study evaluates the effects of carbon dioxide (CO2) on pre- and prometamorphic Bullfrog larvae. Bullfrogs are a model organism for evaluating potential suppression agents because they are a successful invader worldwide. From experimental trials we estimated that the 24-h 50% and 99% lethal concentration (LC50 and LC99) values for Bullfrog larvae were 371 and 549 mg CO2/L, respectively. Overall, larvae that succumbed to experimental conditions had a lower body condition index than those that survived. We also documented sublethal changes in blood chemistry during prolonged exposure to elevated CO2. Specifically, blood pH decreased by more than 0.5 pH units after 9 h of exposure and both blood partial pressure of CO2 (pCO2) and blood glucose increased. These findings suggest that CO2 treatments can be lethal to Bullfrog larvae under controlled laboratory conditions. We believe this work represents the necessary foundation for further consideration of CO2 as a potential suppression agent for one of the most harmful invaders to freshwater ecosystems.

  16. Quantitative proteomic analysis of thylakoid from two microalgae (Haematococcus pluvialis and Dunaliella salina) reveals two different high light-responsive strategies

    PubMed Central

    Gu, Wenhui; Li, Huan; Zhao, Peipei; Yu, Ruixue; Pan, Guanghua; Gao, Shan; Xie, Xiujun; Huang, Aiyou; He, Linwen; Wang, Guangce

    2014-01-01

    Under high light (HL) stress, astaxanthin-accumulating Haematococcus pluvialis and β-carotene-accumulating Dunaliella salina showed different responsive patterns. To elucidate cellular-regulating strategies photosynthetically and metabolically, thylakoid membrane proteins in H. pluvialis and D. salina were extracted and relatively quantified after 0 h, 24 h and 48 h of HL stress. Proteomic analysis showed that three subunits of the cytochrome b6/f complex were greatly reduced under HL stress in H. pluvialis, while they were increased in D. salina. Additionally, the major subunits of both photosystem (PS) II and PSI reaction center proteins were first reduced and subsequently recovered in H. pluvialis, while they were gradually reduced in D. salina. D. salina also showed a greater ability to function using the xanthophyll-cycle and the cyclic photosynthetic electron transfer pathway compared to H. pluvialis. We propose a reoriented and effective HL-responsive strategy in H. pluvialis, enabling it to acclimate under HL. The promising metabolic pathway described here contains a reorganized pentose phosphate pathway, Calvin cycle and glycolysis pathway participating in carbon sink formation under HL in H. pluvialis. Additionally, the efficient carbon reorientation strategy in H. pluvialis was verified by elevated extracellular carbon assimilation and rapid conversion into astaxanthin. PMID:25335577

  17. Quantitative proteomic analysis of thylakoid from two microalgae (Haematococcus pluvialis and Dunaliella salina) reveals two different high light-responsive strategies.

    PubMed

    Gu, Wenhui; Li, Huan; Zhao, Peipei; Yu, Ruixue; Pan, Guanghua; Gao, Shan; Xie, Xiujun; Huang, Aiyou; He, Linwen; Wang, Guangce

    2014-01-01

    Under high light (HL) stress, astaxanthin-accumulating Haematococcus pluvialis and β-carotene-accumulating Dunaliella salina showed different responsive patterns. To elucidate cellular-regulating strategies photosynthetically and metabolically, thylakoid membrane proteins in H. pluvialis and D. salina were extracted and relatively quantified after 0 h, 24 h and 48 h of HL stress. Proteomic analysis showed that three subunits of the cytochrome b6/f complex were greatly reduced under HL stress in H. pluvialis, while they were increased in D. salina. Additionally, the major subunits of both photosystem (PS) II and PSI reaction center proteins were first reduced and subsequently recovered in H. pluvialis, while they were gradually reduced in D. salina. D. salina also showed a greater ability to function using the xanthophyll-cycle and the cyclic photosynthetic electron transfer pathway compared to H. pluvialis. We propose a reoriented and effective HL-responsive strategy in H. pluvialis, enabling it to acclimate under HL. The promising metabolic pathway described here contains a reorganized pentose phosphate pathway, Calvin cycle and glycolysis pathway participating in carbon sink formation under HL in H. pluvialis. Additionally, the efficient carbon reorientation strategy in H. pluvialis was verified by elevated extracellular carbon assimilation and rapid conversion into astaxanthin.

  18. Neural regulation of pupariation in tsetse larvae.

    PubMed

    Zdárek, J; Denlinger, D L

    1992-12-01

    A neural mechanism coordinates pupariation behavior and tanning in the tsetse larva. At parturition, the mature larva has already received sufficient ecdysteroid to commit the epidermal cells to metamorphosis but, before sclerotization and tanning of the cuticle can begin, the larva must first select a pupariation site and then proceed through a stereotypic sequence of pupariation behavior that culminates in the formation of a smooth, ovoid puparium. Both pupariation behavior and tanning are inhibited by the central nervous system (CNS) during the wandering phase. This central inhibition is maintained by sensory input originating in the extreme posterior region of the body. At the transition from wandering to pupariation, the posterior signal that induces inhibition of pupariation behavior is removed and the larva begins the contractions associated with pupariation, but the CNS inhibition of tanning persists. At this point, separation of the body into two halves by ligation or nerve transection prevents tanning of the anterior half (containing the CNS), whereas the denervated integument of the posterior half tans completely. Transection of nerves to the midline of the body produces larvae with a tanning pattern that ends abruptly along a sagittal plane, implying that the central control of this process is uncoupled between the left and right regions of the CNS. A few minutes later, when the final shape of the puparium is completed, the CNS inhibition is lifted and the tanning process begins. At this time, separation of the body into two halves by ligation or nerve transection has no inhibitory effects on either part. Exogenous ecdysteroids fail to release the CNS inhibition, and hemolymph containing the pupariation factors from Sarcophaga bullata have no accelerating effects on tsetse pupariation. These results imply that regulation of metamorphosis in the insect integument is not the exclusive domain of blood-borne hormones.

  19. Appetitive associative olfactory learning in Drosophila larvae.

    PubMed

    Apostolopoulou, Anthi A; Widmann, Annekathrin; Rohwedder, Astrid; Pfitzenmaier, Johanna E; Thum, Andreas S

    2013-02-18

    In the following we describe the methodological details of appetitive associative olfactory learning in Drosophila larvae. The setup, in combination with genetic interference, provides a handle to analyze the neuronal and molecular fundamentals of specifically associative learning in a simple larval brain. Organisms can use past experience to adjust present behavior. Such acquisition of behavioral potential can be defined as learning, and the physical bases of these potentials as memory traces. Neuroscientists try to understand how these processes are organized in terms of molecular and neuronal changes in the brain by using a variety of methods in model organisms ranging from insects to vertebrates. For such endeavors it is helpful to use model systems that are simple and experimentally accessible. The Drosophila larva has turned out to satisfy these demands based on the availability of robust behavioral assays, the existence of a variety of transgenic techniques and the elementary organization of the nervous system comprising only about 10,000 neurons (albeit with some concessions: cognitive limitations, few behavioral options, and richness of experience questionable). Drosophila larvae can form associations between odors and appetitive gustatory reinforcement like sugar. In a standard assay, established in the lab of B. Gerber, animals receive a two-odor reciprocal training: A first group of larvae is exposed to an odor A together with a gustatory reinforcer (sugar reward) and is subsequently exposed to an odor B without reinforcement. Meanwhile a second group of larvae receives reciprocal training while experiencing odor A without reinforcement and subsequently being exposed to odor B with reinforcement (sugar reward). In the following both groups are tested for their preference between the two odors. Relatively higher preferences for the rewarded odor reflect associative learning--presented as a performance index (PI). The conclusion regarding the associative

  20. Carabid larvae as predators of weed seeds: granivory in larvae of Amara eurynota (Coleoptera: Carabidae).

    PubMed

    Saska, Pavel

    2004-01-01

    Up to date we do not have much information about predation on seeds by larvae of ground beetles. One of the reasons why such knowledge is important is that granivorous larvae contribute to predation of weed seeds. In this study, the food requirements of larvae of autumn breeding carabid species Amara eurynota (Panzer) were investigated in the laboratory and a hypothesis, that they are granivorous was tested. Insect diet (Tenebrio molitor larvae), three seed diets (seeds of Artemisia vulgaris, Tripleurospermum inodorum or Urtica dioica or a mixed diet (T. molitor + A. uulgaris) were used as food. For larvae of A. eurynota, seeds are essential for successful completion of development, because all those fed pure insect diet died before pupation. However, differences in suitability were observed between pure seed diets. Larvae fed seeds of A. vulgaris had the lowest mortality and fastest development of the seed diets. Those fed seeds of T. inodorum had also low mortality, but the development was prolonged in the third instar. In contrast, development of larvae reared on seeds of U. dioica was slowest of the tested diets and could not be completed, as all individuals died before pupation. When insects were included to seed diet of A. vulgaris (mixed diet), the duration of development shortened, but mortality remained the same when compared to seed diet of A. vulgaris. According to the results it was concluded that larvae of A. eurynota are granivorous. A mixed diet and seed diets of A. uulgaris and T. inodorum were suitable and insect diet and seeds of U. dioica were unsuitable diets in this experiment.

  1. [Larvae of barnacles (Cirripedia: Thoracica) in the White sea plankton].

    PubMed

    Poltarukha, O P

    2003-01-01

    The barnacle fauna in the White Sea is briefly described. The morphology of barnacle larvae in this water body is comparatively analyzed. The characters important for the larvae identification are given particular attention. A classification key was developed for the nauplius and cyprid larvae of barnacles in the White Sea.

  2. Workbook on the Identification of Anopheles Larvae. Preliminary Issue.

    ERIC Educational Resources Information Center

    Pratt, Harry D.; Stojanovich, Chester J.

    This self-instructional booklet is designed to enable malarial control workers to identify the larvae of "Anopheles" species that are important malaria vectors. The morphological features of the larvae are illustrated in a programed booklet, which also contains an illustrated taxonomic key to 25 species of anopheline larvae. A glossary and a short…

  3. An Introduction to the Identification of Chironomid Larvae.

    ERIC Educational Resources Information Center

    Mason, William T., Jr.

    This publication is an introductory guide to the identification of Chironomid (Midge) larvae. The larvae of these small flies are an important link in the food chain between algae and microinvertebrates. As a family, the larvae exhibit a wide range of tolerance to environmental factors such as amounts and types of pollutants. Much of this…

  4. Sedimentation in Michigan basin during earliest Salina: evidence for an excursion from eustacy

    SciTech Connect

    Cercone, K.R.

    1986-08-01

    A basal A-1 evaporite member of the Upper Silurian Salina Group, a marine evaporite sequence, appears to record a time of lowered sea level in the Michigan basin. Indicators of shallow sabkha deposition, such as nodular anhydrite and nonplanar stromatolites, occur in parts of the A-1 evaporite. This unit also contains scattered nodules of borate, a nonmarine evaporite, and the bittern salt sylvite. The petrologic evidence for lowered sea level is supported by studies showing that Middle Silurian reefal buildups within the Michigan basin were subaerially exposed during or immediately prior to A-1 evaporite deposition. However, other studies concluded that carbonate platforms in Indiana and Illinois continued to host flourishing Silurian reef communities throughout A-1 evaporite deposition, under conditions of high global sea levels. The conflicting evidence can be resolved only by postulating that the Michigan basin became isolated from surrounding epeiric seas during A-1 evaporite deposition. Tidal and peritidal carbonates - the Greenfield, Limberlost, Sugar Run, and Engadine dolomites - were deposited at the edge of the Michigan basin during this time. These units could have served both as sills and as shorelines that separated open epeiric seas from a partly desiccated basin. Evaporating brines, pooled below sea level in the basin, could have been replenished by seawater and meteoric water flowing through shallow inlets or seeping into the basin through the subsurface. Basin isolation may have been enhanced by minor eustatic fluctuations in sea level and by the constraints on shallow-water circulation in epeiric seas. Therefore, in analogy to the Miocene desiccation of the Mediterranean, the large apparent drop in sea level recorded by the A-1 evaporite would have been a local rather than a eustatic change.

  5. Oxidative stress is a mediator for increased lipid accumulation in a newly isolated Dunaliella salina strain.

    PubMed

    Yilancioglu, Kaan; Cokol, Murat; Pastirmaci, Inanc; Erman, Batu; Cetiner, Selim

    2014-01-01

    Green algae offer sustainable, clean and eco-friendly energy resource. However, production efficiency needs to be improved. Increasing cellular lipid levels by nitrogen depletion is one of the most studied strategies. Despite this, the underlying physiological and biochemical mechanisms of this response have not been well defined. Algae species adapted to hypersaline conditions can be cultivated in salty waters which are not useful for agriculture or consumption. Due to their inherent extreme cultivation conditions, use of hypersaline algae species is better suited for avoiding culture contamination issues. In this study, we identified a new halophilic Dunaliella salina strain by using 18S ribosomal RNA gene sequencing. We found that growth and biomass productivities of this strain were directly related to nitrogen levels, as the highest biomass concentration under 0.05 mM or 5 mM nitrogen regimes were 495 mg/l and 1409 mg/l, respectively. We also confirmed that nitrogen limitation increased cellular lipid content up to 35% under 0.05 mM nitrogen concentration. In order to gain insight into the mechanisms of this phenomenon, we applied fluorometric, flow cytometric and spectrophotometric methods to measure oxidative stress and enzymatic defence mechanisms. Under nitrogen depleted cultivation conditions, we observed increased lipid peroxidation by measuring an important oxidative stress marker, malondialdehyde and enhanced activation of catalase, ascorbate peroxidase and superoxide dismutase antioxidant enzymes. These observations indicated that oxidative stress is accompanied by increased lipid content in the green alga. In addition, we also showed that at optimum cultivation conditions, inducing oxidative stress by application of exogenous H2O2 leads to increased cellular lipid content up to 44% when compared with non-treated control groups. Our results support that oxidative stress and lipid overproduction are linked. Importantly, these results also suggest that

  6. Halomonas socia sp. nov., isolated from high salt culture of Dunaliella salina.

    PubMed

    Cao, Jiao; Ma, Huai-Yuan; Li, Hai-Yu; Wang, Kui-Rong; Ruan, Kun; Bai, Lin-Han

    2013-07-01

    A moderately halophilic bacteria designed strain NY-011(T) was isolated from the high salt culture of Dunaliella salina in Chengdu of Sichuan Province, China. The isolate was Gram-negative, nonmotile, rod-shaped and 12.5-21.6 μm in length. Colonies on solid media are circular, wet, smooth and cream. The strain grew optimally at 37 °C, pH 7.0 and in the presence of 8 % NaCl. Acid was produced from glycerol, D-arabinose, glucose, trehalose, inositol, mannose, mannitol, sucrose, maltose and sorbitol. Catalase is produced but not oxidase. The major fatty acids are C18: 1ω7c (37.59 %), C19: 0 cyclo ω8c (18.29 %), C16: 0 (16.05 %) and C6: 0 (12.43 %). The predominant respiratory lipoquinone found in strain NY-011(T) is ubiquinone with nine isoprene units (Q-9). The genomic DNA G + C content of strain NY-011(T) was 62.7 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain NY-011(T) belonged to the genus Halomonas. The highest levels of 16S rRNA gene sequence similarity were found between the strain NY-011(T) and H. pantelleriensis (sequence similarity 98.43 %). However, the levels of DNA-DNA relatedness between them were only 23.1 %. In addition, the strain NY-011(T) had a phenotypic profile that readily distinguished it from H. pantelleriensis. The strain NY-011(T) therefore represents a new species of the genus Halomonas, for which the name Halomonas socia sp. nov. is proposed, with NY-011(T) (=CCTCC AB 2011033(T) = KCTC 23671(T)) as the type strain.

  7. Low Temperature-Induced Alterations in the Chloroplast and Microsomal Membranes of Dunaliella salina1

    PubMed Central

    Lynch, Daniel V.; Thompson, Guy A.

    1982-01-01

    The metabolic regulation of membrane lipid composition has been examined using the cell wall-less, unicellular green alga Dunaliella salina (UTEX 1644) as a model system. Low temperature stress was employed to initiate and study the regulatory response. When cultures growing logarithmically at 30°C were chilled to 12°C, cell division ceased for approximately 100 hours, and then the cells resumed logarithmic growth at a slower rate. The phospholipid, glycolipid and protein content, on a per cell basis, was, in each case, approximately 20% higher in cells grown at 12°C. The volume of the 12°C-acclimated cells was 2.8 times that of 30°C-grown cells. The quantity of chloroplast membrane, as determined by morphometric analysis, was 20% greater, whereas the content of microsomal membrane material was more elevated, being approximately 2.8 times that of 30°C-grown cells. Lipid compositional analyses were carried out on purified chloroplasts and microsomes isolated from Dunaliella grown at 30 and 12°C and also from cells 12 and 60 hours following a shift from 30 to 12°C. In both chloroplast and microsomal phospholipids fatty acid unsaturation increased during acclimation to low temperature. Generally, microsomal phospholipids responded more quickly and to a greater extent than did chloroplast phospholipids. Despite these alterations, little change in the relative proportions of phospholipid classes was observed in either cell fraction. In sharp contrast to the pattern of phospholipid change, chloroplast glycolipids responded to low temperature by significantly increasing the proportion of one specific class, digalactosyl diglycerides, relative to monogalactosyl diglycerides, while showing minimal change in fatty acid distribution within any given glycolipid class. The ease and rapidity with which Dunaliella cells can be manipulated with respect to environmental stress and isolation of intact cell organelles makes it particularly well suited for research on

  8. Effects of iron deficiency on iron binding and internalization into acidic vacuoles in Dunaliella salina.

    PubMed

    Paz, Yakov; Shimoni, Eyal; Weiss, Meira; Pick, Uri

    2007-07-01

    Uptake of iron in the halotolerant alga Dunaliella salina is mediated by a transferrin-like protein (TTf), which binds and internalizes Fe(3+) ions. Recently, we found that iron deficiency induces a large enhancement of iron binding, which is associated with accumulation of three other plasma membrane proteins that associate with TTf. In this study, we characterized the kinetic properties of iron binding and internalization and identified the site of iron internalization. Iron deficiency induces a 4-fold increase in Fe binding, but only 50% enhancement in the rate of iron uptake and also increases the affinity for iron and bicarbonate, a coligand for iron binding. These results indicate that iron deprivation leads to accumulation and modification of iron-binding sites. Iron uptake in iron-sufficient cells is preceded by an apparent time lag, resulting from prebound iron, which can be eliminated by unloading iron-binding sites. Iron is tightly bound to surface-exposed sites and hardly exchanges with medium iron. All bound iron is subsequently internalized. Accumulation of iron inhibits further iron binding and internalization. The vacuolar inhibitor bafilomycin inhibits iron uptake and internalization. Internalized iron was localized by electron microscopy within vacuolar structures that were identified as acidic vacuoles. Iron internalization is accompanied by endocytosis of surface proteins into these acidic vacuoles. A novel kinetic mechanism for iron uptake is proposed, which includes two pools of bound/compartmentalized iron separated by a rate-limiting internalization stage. The major parameter that is modulated by iron deficiency is the iron-binding capacity. We propose that excessive iron binding in iron-deficient cells serves as a temporary reservoir for iron that is subsequently internalized. This mechanism is particularly suitable for organisms that are exposed to large fluctuations in iron availability. PMID:17513481

  9. Oxidative Stress Is a Mediator for Increased Lipid Accumulation in a Newly Isolated Dunaliella salina Strain

    PubMed Central

    Yilancioglu, Kaan; Cokol, Murat; Pastirmaci, Inanc; Erman, Batu; Cetiner, Selim

    2014-01-01

    Green algae offer sustainable, clean and eco-friendly energy resource. However, production efficiency needs to be improved. Increasing cellular lipid levels by nitrogen depletion is one of the most studied strategies. Despite this, the underlying physiological and biochemical mechanisms of this response have not been well defined. Algae species adapted to hypersaline conditions can be cultivated in salty waters which are not useful for agriculture or consumption. Due to their inherent extreme cultivation conditions, use of hypersaline algae species is better suited for avoiding culture contamination issues. In this study, we identified a new halophilic Dunaliella salina strain by using 18S ribosomal RNA gene sequencing. We found that growth and biomass productivities of this strain were directly related to nitrogen levels, as the highest biomass concentration under 0.05 mM or 5 mM nitrogen regimes were 495 mg/l and 1409 mg/l, respectively. We also confirmed that nitrogen limitation increased cellular lipid content up to 35% under 0.05 mM nitrogen concentration. In order to gain insight into the mechanisms of this phenomenon, we applied fluorometric, flow cytometric and spectrophotometric methods to measure oxidative stress and enzymatic defence mechanisms. Under nitrogen depleted cultivation conditions, we observed increased lipid peroxidation by measuring an important oxidative stress marker, malondialdehyde and enhanced activation of catalase, ascorbate peroxidase and superoxide dismutase antioxidant enzymes. These observations indicated that oxidative stress is accompanied by increased lipid content in the green alga. In addition, we also showed that at optimum cultivation conditions, inducing oxidative stress by application of exogenous H2O2 leads to increased cellular lipid content up to 44% when compared with non-treated control groups. Our results support that oxidative stress and lipid overproduction are linked. Importantly, these results also suggest that

  10. Oxidative stress is a mediator for increased lipid accumulation in a newly isolated Dunaliella salina strain.

    PubMed

    Yilancioglu, Kaan; Cokol, Murat; Pastirmaci, Inanc; Erman, Batu; Cetiner, Selim

    2014-01-01

    Green algae offer sustainable, clean and eco-friendly energy resource. However, production efficiency needs to be improved. Increasing cellular lipid levels by nitrogen depletion is one of the most studied strategies. Despite this, the underlying physiological and biochemical mechanisms of this response have not been well defined. Algae species adapted to hypersaline conditions can be cultivated in salty waters which are not useful for agriculture or consumption. Due to their inherent extreme cultivation conditions, use of hypersaline algae species is better suited for avoiding culture contamination issues. In this study, we identified a new halophilic Dunaliella salina strain by using 18S ribosomal RNA gene sequencing. We found that growth and biomass productivities of this strain were directly related to nitrogen levels, as the highest biomass concentration under 0.05 mM or 5 mM nitrogen regimes were 495 mg/l and 1409 mg/l, respectively. We also confirmed that nitrogen limitation increased cellular lipid content up to 35% under 0.05 mM nitrogen concentration. In order to gain insight into the mechanisms of this phenomenon, we applied fluorometric, flow cytometric and spectrophotometric methods to measure oxidative stress and enzymatic defence mechanisms. Under nitrogen depleted cultivation conditions, we observed increased lipid peroxidation by measuring an important oxidative stress marker, malondialdehyde and enhanced activation of catalase, ascorbate peroxidase and superoxide dismutase antioxidant enzymes. These observations indicated that oxidative stress is accompanied by increased lipid content in the green alga. In addition, we also showed that at optimum cultivation conditions, inducing oxidative stress by application of exogenous H2O2 leads to increased cellular lipid content up to 44% when compared with non-treated control groups. Our results support that oxidative stress and lipid overproduction are linked. Importantly, these results also suggest that

  11. Habitat of oil in the Lindsborg field, Salina basin, north-central Kansas

    SciTech Connect

    Newell, K.D. )

    1991-03-01

    The Lindsborg field was discovered in 1938, and is now 14 mi in length and 1-2 mi in width. It has a projected ultimate recovery of 16 MMBO. Three pay zones (5-20 ft thick) produce in the field. The Simpson pay zone (Middle Ordovician) is a well-rounded, quartzitic sandstone that is interpreted to be a paralic, high-energy shelf deposit. The Viola pay (Middle Ordovician) appears to be a dolomitic, lime grainstone but no cores are available to confirm this. The uppermost pay zone, the Upper Ordovician Maquoketa, is a finely laminated, vuggy, cherry dolomite interpreted to have been deposited as a subtidal lime mudstone in a restricted lagoon. The Simpson and Viola pays are structurally trapped in culminations along the crest of the Lindsborg anticline. Although the Maquoketa pay is structurally trapped with the other pay zones in the southern half of the field, its locus of production in the north half of the fields extends 100 ft vertically down the western flank of the anticline. The trapping mechanism is unclear due to lack of core control and modern logging suites, but it may be subtle updip diagenetic change from vuggy to nonvuggy dolomite. The Simpson and Maquoketa oils are geochemically distinct. Both may reflect efficient local source-to-reservoir migration from originally rich but marginally mature Ordovician and Devonian shales that contact each pay zone. If oil in the Lindsborg field is locally generated, the prospectivity of the relatively unproductive and underexplored Salina basin may be enhanced.

  12. Complete Genome Sequence of Paenibacillus larvae MEX14, Isolated from Honey Bee Larvae from the Xochimilco Quarter in Mexico City.

    PubMed

    Peréz de la Rosa, D; Pérez de la Rosa, J J; Cossio-Bayugar, R; Miranda-Miranda, E; Lozano, L; Bravo-Díaz, M A; Rocha-Martínez, M K; Sachman-Ruiz, B

    2015-08-27

    Paenibacillus larvae strain MEX14 is a facultative anaerobic endospore-forming bacterium that infects Apis mellifera larvae. Strain MEX14 was isolated from domestic bee larvae collected in a backyard in Mexico City. The estimated genome size was determined to be 4.18 Mb, and it harbors 4,806 protein coding genes (CDSs).

  13. Complete Genome Sequence of Paenibacillus larvae MEX14, Isolated from Honey Bee Larvae from the Xochimilco Quarter in Mexico City

    PubMed Central

    Peréz de la Rosa, D.; Pérez de la Rosa, J. J.; Cossio-Bayugar, R.; Miranda-Miranda, E.; Lozano, L.; Bravo-Díaz, M. A.; Rocha-Martínez, M. K.

    2015-01-01

    Paenibacillus larvae strain MEX14 is a facultative anaerobic endospore-forming bacterium that infects Apis mellifera larvae. Strain MEX14 was isolated from domestic bee larvae collected in a backyard in Mexico City. The estimated genome size was determined to be 4.18 Mb, and it harbors 4,806 protein coding genes (CDSs). PMID:26316636

  14. Reporting a new siderophore based Ca(2+) selective chemosensor that works as a staining agent in the live organism Artemia.

    PubMed

    Raju, M; Nair, Ratish R; Raval, Ishan H; Haldar, Soumya; Chatterjee, Pabitra B

    2015-11-21

    A Ca(2+)-specific chemosensor involving acyclic non-ether and non-carboxylato-type metal chelating ligands is rare. The tetradentate OONO artificial receptor, HL, possessing a sulfur-containing intermediate siderophore aeruginic acid, tethered to a rhodamine 6G based signalling unit in a single molecule has been synthesized. The fluoroionophore required excitation in the visible wavelength (510 nm) and showed highly selective and sensitive detection of Ca(2+) ions in 100% water solution in HEPES buffer at physiological pH (7.4). The probe HL, with LOD as low as 70 nM, behaves reversibly and showed nearly 17-fold enhanced selectivity for Ca(2+) over other cell abundant alkali and alkaline metal ions such as Na(+), K(+), Li(+), and Mg(2+) without any intervention. Job's plot, (1)H NMR titration and ESI-MS data provided corroborative evidence in support of 1 : 1 association between HL and Ca(2+). From a wide range of transition and heavy metal ions series, HL also binds Cu(2+). However, the use of l-cysteine removes the interference from Cu(2+) and results in highly selective detection specificity of HL for Ca(2+). As a reversible "off-on-off" fluorescent chemosensor, it is possible to detect Ca(2+) at as low as 5 μM in the midgut region of the gastrointestinal tract of the live animal Artemia, a brine shrimp. PMID:26460620

  15. Probing the phenomenon of trained immunity in invertebrates during a transgenerational study, using brine shrimp Artemia as a model system

    PubMed Central

    Norouzitallab, Parisa; Baruah, Kartik; Biswas, Priyanka; Vanrompay, Daisy; Bossier, Peter

    2016-01-01

    The invertebrate’s innate immune system was reported to show some form of adaptive features, termed trained immunity. However, the memory characteristics of innate immune system and the mechanisms behind such phenomena remain unclear. Using the invertebrate model Artemia, we verified the possibility or impossibility of trained immunity, examining the presence or absence of enduring memory against homologous and heterologous antigens (Vibrio spp.) during a transgenerational study. We also determined the mechanisms behind such phenomenon. Our results showed the occurrence of memory and partial discrimination in Artemia’s immune system, as manifested by increased resistance, for three successive generations, of the progenies of Vibrio-exposed ancestors towards a homologous bacterial strain, rather than to a heterologous strain. This increased resistance phenotype was associated with elevated levels of hsp70 and hmgb1 signaling molecules and alteration in the expression of key innate immunity-related genes. Our results also showed stochastic pattern in the acetylation and methylation levels of H4 and H3K4me3 histones, respectively, in the progenies whose ancestors were challenged. Overall results suggest that innate immune responses in invertebrates have the capacity to be trained, and epigenetic reprogramming of (selected) innate immune effectors is likely to have central place in the mechanisms leading to trained immunity. PMID:26876951

  16. Depression of nuclear transcription and extension of mRNA half-life under anoxia in Artemia franciscana embryos.

    PubMed

    van Breukelen, F; Maier, R; Hand, S C

    2000-04-01

    Transcriptional activity, as assessed by nuclear run-on assays, was constant during 10 h of normoxic development for embryos of the brine shrimp Artemia franciscana. Exposure of embryos to only 4 h of anoxia resulted in a 79.3+/-1 % decrease in levels of in-vivo-initiated transcripts, and transcription was depressed by 88. 2+/-0.7 % compared with normoxic controls after 24 h of anoxia (means +/- s.e.m., N=3). Initiation of transcription was fully restored after 1 h of normoxic recovery. Artificially lowering the intracellular pH of aerobic embryos to the value reflective of anoxia (pH 6.7) showed that acidification alone explained over half the transcriptional arrest. Initiation of transcription was not rescued by application of 80 % carbon monoxide under anoxia, which suggests that heme-based oxygen sensing is not involved in this global arrest. When these transcriptional data are combined with the finding that mRNA levels are unchanged for at least 6 h of anoxia, it is clear that the half-life of mRNA is extended at least 8.5-fold compared with that in aerobic embryos. In contrast to the activation of compensatory mechanisms to cope with anoxia that occurs in mammalian cells, A. franciscana embryos enter a metabolically depressed state in which gene expression and mRNA turnover are cellular costs apparently not compatible with survival and in which extended tolerance supercedes the requirement for continued metabolic function. PMID:10708633

  17. Estimate of the effects of ultraviolet radiation on the mortality of Artemia franciscana in naupliar and adult stages

    NASA Astrophysics Data System (ADS)

    Dattilo, Arduino M.; Bracchini, Luca; Carlini, Laura; Loiselle, Steven; Rossi, Claudio

    2005-07-01

    The impact of different doses of artificial ultraviolet (UV) radiation on the growth stages of a marine zooplankton was investigated using laboratory microcosms. Mortality percentages of naupliar and adult samples of Artemia franciscana were recorded in relation to different UV doses (single exposure: 75, 150, 300, 600, 1,200, 2,400, 3,900, 7,800 J m-2) at specific observation times after exposure (24, 48, 72, 96 and 120 h). The relationship between mortality percentage and UV dose showed significant differences in relation to the zooplankton growth stage. The elevated susceptibility of the naupliar samples to UV radiation is described through a mortality model based on a logistic equation. The data analysis shows that the slope of mortality versus dose remains the same for the two growth stages while the lethal dose in the naupliar stage was 3.3 smaller than that determined for the adult stage. The slope of the UV mortality rate versus post-incubation time was found to be significantly different (P<0.05) at low UV doses for the two life stages examined, i.e. naupliar and adult. The lower value of LD50 in naupliar stages compared to that for adults confirms that in the early growth stage this marine zooplankton is more susceptible to UV radiation.

  18. Polymorphism and structure of the gene coding for the alpha 1 subunit of the Artemia franciscana Na/K-ATPase.

    PubMed Central

    García-Sáez, A; Perona, R; Sastre, L

    1997-01-01

    Genomic clones coding for one of the two identified Artemia franciscana Na/K-ATPase alpha subunits, the alpha 1 subunit, have been isolated. Several overlapping clones were obtained, although their restriction maps showed a large heterogeneity. Sequencing of their exons showed that they differ in up to 3.46% of their nucleotides in translated regions and 8.18% in untranslated regions. Southern blot analysis of DNA purified from different lots of A. franciscana cysts and from isolated individuals suggests that the variation is due to the existence of multiple Na/K-ATPase alpha 1 subunit alleles in A. franciscana. The Na/K-ATPase alpha 1 subunit gene is divided into 15 exons. Ten of the 14 introns are located in identical positions in this gene as in the human Na/K-ATPase alpha 3 subunit gene. Analysis of the 5' flanking region of the gene has allowed identification of the transcription-initiation sites. The adjacent upstream region has been shown to have functional promoter activity in cultured mammalian cells, suggesting the evolutionary conservation of some of the promoter regulatory sequences. PMID:9020888

  19. Does a Change from Whole to Powdered Food (Artemia franciscana eggs) Increase Oviposition in the Ladybird Coleomegilla maculata?

    PubMed Central

    Riddick, Eric W.; Wu, Zhixin

    2015-01-01

    The limited availability of alternative foods to replace natural prey hinders cost-effective mass production of ladybird beetles for augmentative biological control. We compared the effects of powdered vs. whole Artemia franciscana (A. franciscana) (brine shrimp) eggs with or without a dietary supplement on development and reproduction of Coleomegilla maculata (C. maculata) (Coleoptera: Coccinellidae). We tested the hypotheses that (1) powdered A. franciscana eggs are more suitable than whole eggs; and (2) palmitic acid, a common fatty acid in natural prey, i.e., aphids, is an effective dietary supplement. Development time, pre-imaginal survival, sex ratio, and body weight of adults did not differ significantly amongst individuals fed powdered vs. whole eggs, with or without 5% palmitic acid. Significantly more oviposition occurred when females were fed powdered eggs than whole eggs and powdered eggs with 5% palmitic acid than whole eggs with or without 5% palmitic acid. A weak functional relationship was found between pre-oviposition time and total oviposition by females fed powdered eggs with 5% palmitic acid; pre-oviposition time decreased as oviposition increased. Food treatments had no significant differential effect on progeny (egg) hatch rate. In conclusion, a simple change in A. franciscana egg texture and particle size (i.e., blending whole eggs into a dust-like powder) increases oviposition in C. maculata. Supplementing powdered eggs with 5% palmitic acid might accelerate oogenesis (egg maturation) in some females. PMID:26466902

  20. Does a Change from Whole to Powdered Food (Artemia franciscana eggs) Increase Oviposition in the Ladybird Coleomegilla maculata?

    PubMed

    Riddick, Eric W; Wu, Zhixin

    2015-01-01

    The limited availability of alternative foods to replace natural prey hinders cost-effective mass production of ladybird beetles for augmentative biological control. We compared the effects of powdered vs. whole Artemia franciscana (A. franciscana) (brine shrimp) eggs with or without a dietary supplement on development and reproduction of Coleomegilla maculata (C. maculata) (Coleoptera: Coccinellidae). We tested the hypotheses that (1) powdered A. franciscana eggs are more suitable than whole eggs; and (2) palmitic acid, a common fatty acid in natural prey, i.e., aphids, is an effective dietary supplement. Development time, pre-imaginal survival, sex ratio, and body weight of adults did not differ significantly amongst individuals fed powdered vs. whole eggs, with or without 5% palmitic acid. Significantly more oviposition occurred when females were fed powdered eggs than whole eggs and powdered eggs with 5% palmitic acid than whole eggs with or without 5% palmitic acid. A weak functional relationship was found between pre-oviposition time and total oviposition by females fed powdered eggs with 5% palmitic acid; pre-oviposition time decreased as oviposition increased. Food treatments had no significant differential effect on progeny (egg) hatch rate. In conclusion, a simple change in A. franciscana egg texture and particle size (i.e., blending whole eggs into a dust-like powder) increases oviposition in C. maculata. Supplementing powdered eggs with 5% palmitic acid might accelerate oogenesis (egg maturation) in some females.

  1. Larva of Palaemnema brasiliensis Machado (Odonata: Platystictidae), from Amazonas, Brazil.

    PubMed

    Neiss, Ulisses Gaspar; Hamada, Neusa

    2016-02-09

    The larva of Palaemnema brasiliensis Machado, 2009 is described and illustrated based on last-instar larvae and exuviae of reared larvae collected in a blackwater stream in Barcelos and Presidente Figueiredo municipalities, Amazonas state, Brazil. The larva of P. brasiliensis can be distinguished from the two South American species of the genus with described larvae (P. clementia Selys and P. mutans Calvert), mainly by presence of a single obtuse cusp on the labial palp, the presence and configuration of setae in the caudal lamellae, and the proportional length of terminal filaments of the caudal lamellae. The family is recorded here for the first time in Brazilian state of Amazonas.

  2. Larva of Palaemnema brasiliensis Machado (Odonata: Platystictidae), from Amazonas, Brazil.

    PubMed

    Neiss, Ulisses Gaspar; Hamada, Neusa

    2016-01-01

    The larva of Palaemnema brasiliensis Machado, 2009 is described and illustrated based on last-instar larvae and exuviae of reared larvae collected in a blackwater stream in Barcelos and Presidente Figueiredo municipalities, Amazonas state, Brazil. The larva of P. brasiliensis can be distinguished from the two South American species of the genus with described larvae (P. clementia Selys and P. mutans Calvert), mainly by presence of a single obtuse cusp on the labial palp, the presence and configuration of setae in the caudal lamellae, and the proportional length of terminal filaments of the caudal lamellae. The family is recorded here for the first time in Brazilian state of Amazonas. PMID:27395963

  3. High-EPA Biomass from Nannochloropsis salina Cultivated in a Flat-Panel Photo-Bioreactor on a Process Water-Enriched Growth Medium.

    PubMed

    Safafar, Hamed; Hass, Michael Z; Møller, Per; Holdt, Susan L; Jacobsen, Charlotte

    2016-01-01

    Nannochloropsis salina was grown on a mixture of standard growth media and pre-gasified industrial process water representing effluent from a local biogas plant. The study aimed to investigate the effects of enriched growth media and cultivation time on nutritional composition of Nannochloropsis salina biomass, with a focus on eicosapentaenoic acid (EPA). Variations in fatty acid composition, lipids, protein, amino acids, tocopherols and pigments were studied and results compared to algae cultivated on F/2 media as reference. Mixed growth media and process water enhanced the nutritional quality of Nannochloropsis salina in laboratory scale when compared to algae cultivated in standard F/2 medium. Data from laboratory scale translated to the large scale using a 4000 L flat panel photo-bioreactor system. The algae growth rate in winter conditions in Denmark was slow, but results revealed that large-scale cultivation of Nannochloropsis salina at these conditions could improve the nutritional properties such as EPA, tocopherol, protein and carotenoids compared to laboratory-scale cultivated microalgae. EPA reached 44.2% ± 2.30% of total fatty acids, and α-tocopherol reached 431 ± 28 µg/g of biomass dry weight after 21 days of cultivation. Variations in chemical compositions of Nannochloropsis salina were studied during the course of cultivation. Nannochloropsis salina can be presented as a good candidate for winter time cultivation in Denmark. The resulting biomass is a rich source of EPA and also a good source of protein (amino acids), tocopherols and carotenoids for potential use in aquaculture feed industry. PMID:27483291

  4. High-EPA Biomass from Nannochloropsis salina Cultivated in a Flat-Panel Photo-Bioreactor on a Process Water-Enriched Growth Medium

    PubMed Central

    Safafar, Hamed; Hass, Michael Z.; Møller, Per; Holdt, Susan L.; Jacobsen, Charlotte

    2016-01-01

    Nannochloropsis salina was grown on a mixture of standard growth media and pre-gasified industrial process water representing effluent from a local biogas plant. The study aimed to investigate the effects of enriched growth media and cultivation time on nutritional composition of Nannochloropsis salina biomass, with a focus on eicosapentaenoic acid (EPA). Variations in fatty acid composition, lipids, protein, amino acids, tocopherols and pigments were studied and results compared to algae cultivated on F/2 media as reference. Mixed growth media and process water enhanced the nutritional quality of Nannochloropsis salina in laboratory scale when compared to algae cultivated in standard F/2 medium. Data from laboratory scale translated to the large scale using a 4000 L flat panel photo-bioreactor system. The algae growth rate in winter conditions in Denmark was slow, but results revealed that large-scale cultivation of Nannochloropsis salina at these conditions could improve the nutritional properties such as EPA, tocopherol, protein and carotenoids compared to laboratory-scale cultivated microalgae. EPA reached 44.2% ± 2.30% of total fatty acids, and α-tocopherol reached 431 ± 28 µg/g of biomass dry weight after 21 days of cultivation. Variations in chemical compositions of Nannochloropsis salina were studied during the course of cultivation. Nannochloropsis salina can be presented as a good candidate for winter time cultivation in Denmark. The resulting biomass is a rich source of EPA and also a good source of protein (amino acids), tocopherols and carotenoids for potential use in aquaculture feed industry. PMID:27483291

  5. Distribution of metals during digestion by cutthroat trout fed benthic invertebrates contaminated in the Clark Fork River, Montana and the Coeur d'Alene River, Idaho, U.S.A., and fed artificially contaminated Artemia

    USGS Publications Warehouse

    Farag, A.M.; Suedkamp, M.J.; Meyer, J.S.; Barrows, R.; Woodward, D.F.

    2000-01-01

    The concentrations of essential amino acids in three, undigested invertebrate diets collected from the Clark Fork River (CFR) for cutthroat trout were similar to each other, but were c. 25-75% less than Artemia that were exposed to a mixture of arsenic, copper, cadmium, lead and zinc in the laboratory. The Artemia diet appeared less palatable and the texture, quantity and appearance of the intestinal contents differed between fish fed the Artemia and CFR diets. The Pb% in the fluid fraction of the intestinal contents was greater for the Artemia (29%) than for the CFR diets (10-17%), and the Cu% in the amino acid plus metal fraction of the intestinal contents was greater for the Artemia (78%) than for two of the three CFR diets (67% and 70%). Intestinal contents of fish fed invertebrate diets collected from various sites on the Coeur d'Alene River (CDA), Idaho, were similar in texture, quantity, and appearance. For fish fed the CDA diets, differences in the distribution of metals among fractions of the digestive fluids appeared to be related to concentrations of metals in the invertebrate diets. Pb% was lowest of all metals in the fluid portion of the intestinal contents. However, >80% of all metals in the hind gut were associated with the particulate fraction where they may still be available for uptake through pinocytosis. (C) 2000 The Fisheries Society of the British Isles.

  6. In vivo toxicity study of Lantana camara

    PubMed Central

    Pour, Badakhshan Mahdi; Sasidharan, Sreenivasan

    2011-01-01

    Objective To investigate the toxicity of methanol extract of various parts (Root, Stem, Leaf, Flower and Fruit) of Lantana camara (L. Camara) in Artemia salina. Methods The methanol extracts of L. camara were tested for in vivo brine shrimp lethality assay. Results All the tested extract exhibited very low toxicity on brine shrimp larva. The results showed that the root extract was the most toxic part of L. camara and may have potential as anticancer agent. Conclusions Methanolic extract of L. camara is relatively safe on short-term exposure. PMID:23569765

  7. Sannastatin, a novel toxic macrolactam polyketide glycoside produced by actinomycete Streptomyces sannanensis.

    PubMed

    Yang, Sheng-Xiang; Gao, Jin-Ming; Zhang, An-Ling; Laatsch, Hartmut

    2011-07-01

    A new rare 20-membered macrocyclic lactam incorporating a diene conjugated olefin, designated sannastatin (1), together with the known structurally related vicenistatin (2), has been isolated from the cultures of Streptomyces sannanensis, a bacteria found in the feces of Ailuropoda melanoleuca. The structure of the new compound was established on the basis of extensive spectroscopic analyses including 1D- and 2D-NMR ((1)H-(1)H COSY, TOCSY, HSQC, HMBC, and NOESY) experiments. Compounds 1 and 2 displayed significant growth inhibitory activity against the brine shrimp (Artemia salina) larvae. PMID:21640585

  8. Spawning and rearing Atlantic menhaden

    SciTech Connect

    Hettler, W.F.

    1981-04-01

    Two-year-old Atlantic menhaden (Brevoortia tyrannus) held in the laboratory at ambient temperatures and salinities for more than 1 year, were induced to spawn by injecting first human chorionic gonadotropin and then carp pituitary powder. Spawning took place at temperatures of 16 to 20/sup 0/C in a 2100-L indoor tank modified to recover the buoyant fertilized eggs. Larvae were reared to the juvenile stage on a diet of cultured rotifers (Brachionus plicatilus), sieved wild zooplankton (64 to 500 ..mu..m), brine shrimp (Artemia salina) nauplii, and powdered trout food.

  9. Brominated aliphatic hydrocarbons and sterols from the sponge Xestospongia testudinaria with their bioactivities.

    PubMed

    Zhou, Xuefeng; Lu, Yanan; Lin, Xiuping; Yang, Bin; Yang, Xianwen; Liu, Yonghong

    2011-10-01

    Four brominated aliphatic hydrocarbons (1-4), including a novel brominated ene-tetrahydrofuran named as mutafuran H (1), and five sterols (5-9) were isolated from the South China Sea sponge Xestospongia testudinaria. The structure of 1 was determined on the basis of NMR ((1)H, (13)C NMR, HSQC, HMBC, (1)H-(1)H COSY, and NOESY), MS, and optical rotation analysis. Known compounds were identified by comparison of their NMR data with those reported in the literature. Compounds 1-4, and 6-9 were evaluated for their toxicity against Artemia salina larvae, and anti-acetylcholinesterase activity.

  10. Analysis of feeding behavior of Drosophila larvae on liquid food.

    PubMed

    Shen, Ping

    2012-05-01

    The food responses of Drosophila larvae offer an excellent opportunity to study the genetic and neural regulation of feeding behavior. Compared with fed larvae, hungry larvae are more likely to display aggressive foraging, rapid food intake, compensatory feeding, and stress-resistant food procurement. Behavioral assays have been developed to quantitatively assess particular aspects of the hunger-driven food response. In combination, these assays help define the specific role of signaling molecules or neurons in the regulation of feeding behavior in foraging larvae. This protocol describes the analysis of larvae feeding on liquid food. The test is designed for quantitative assessment of the food ingestion rate of individual larvae under different energy states. It provides a simple and reliable way to measure the graded modification of the baseline feeding rate of larvae as food deprivation is prolonged. The test is applicable to routine functional testing and larger-scale screening of genetic mutations and biologics that might affect food consumption.

  11. Predatory cannibalism in Drosophila melanogaster larvae.

    PubMed

    Vijendravarma, Roshan K; Narasimha, Sunitha; Kawecki, Tadeusz J

    2013-01-01

    Hunting live prey is risky and thought to require specialized adaptations. Therefore, observations of predatory cannibalism in otherwise non-carnivorous animals raise questions about its function, adaptive significance and evolutionary potential. Here we document predatory cannibalism on larger conspecifics in Drosophila melanogaster larvae and address its evolutionary significance. We found that under crowded laboratory conditions younger larvae regularly attack and consume 'wandering-stage' conspecifics, forming aggregations mediated by chemical cues from the attacked victim. Nutrition gained this way can be significant: an exclusively cannibalistic diet was sufficient for normal development from eggs to fertile adults. Cannibalistic diet also induced plasticity of larval mouth parts. Finally, during 118 generations of experimental evolution, replicated populations maintained under larval malnutrition evolved enhanced propensity towards cannibalism. These results suggest that, at least under laboratory conditions, predation on conspecifics in Drosophila is a functional, adaptive behaviour, which can rapidly evolve in response to nutritional conditions.

  12. Visceral larva migrans (toxocariasis) in Toronto.

    PubMed Central

    Fanning, M; Hill, A; Langer, H M; Keystone, J S

    1981-01-01

    A 7-year-old child was admitted to Toronto's Hospital for Sick Children in 1976 with symptoms and laboratory findings compatible with visceral larva migrans, a disease usually caused by Toxocara canis. This prompted a search for other cases seen at the hospital during the period 1952 through 1978. Only 18 cases were discovered that met at least three of six criteria and thus were considered possible or probably cases of the disease. Three possible cases of ocular toxocariasis during the same period were also uncovered. Fever was the commonest presenting symptom. Eosinophilia, leukocytosis and hyperglobulinemia were the most frequent laboratory findings. In view of the small number of cases found in 27 years at this large pediatric hospital with a broad referral base, it is concluded that visceral larva migrans poses little risk to the health of children in the Toronto area. PMID:7459767

  13. Baculovirus Insecticide Production in Insect Larvae.

    PubMed

    van Beek, Nikolai; Davis, David C

    2016-01-01

    Baculovirus-based insecticides are currently being used worldwide, and new products are in development in many countries. The most dramatic examples of successful baculovirus insecticides are found in soybean in Brazil and cotton in China. Production of baculoviruses is generally done in larvae of a convenient host species, and the level of sophistication varies tremendously between field-collection of infected insects at the one extreme and automated mass manufacturing at the other. Currently, only products with wild type baculoviruses as active ingredients are commercially available. Baculoviruses encoding insecticidal proteins are considered attractive, especially for crops with little tolerance to feeding damage, where speed-of-kill is an important characteristic. Successful field tests with such recombinant baculoviruses have been done in the past, and more tests are ongoing. However, low-cost production of recombinant baculovirus in larvae poses specific problems, due to the short survival time of the production host.In this chapter, benchtop-scale production of two typical baculoviruses is described. First, we describe the production of wild type Helicoverpa zea nucleopolyhedrovirus in bollworm (H. zea) larvae. H. zea larvae are very aggressive and need to be reared in isolation from each other. Second, we describe the production of a recombinant Autographa californica multiple nucleopolyhedrovirus in the non-cannibalistic cabbage looper, Trichoplusia ni. The recombinant baculovirus encodes the insect-specific scorpion toxin LqhIT2. The tetracycline transactivator system enables the production of wild-type quantity and quality product while toxin expression is repressed since normal toxin production would result in premature death of the production host that would limit progeny virus production.

  14. Rickettsia amblyommii infecting Amblyomma americanum larvae.

    PubMed

    Stromdahl, Ellen Y; Vince, Mary A; Billingsley, Peggy M; Dobbs, Nicole A; Williamson, Phillip C

    2008-01-01

    Polymerase chain reaction analysis of Amblyomma americanum adults, nymphs, and larvae from Aberdeen Proving Ground, MD (APG), revealed a very high prevalence of a spotted fever group (SFG) rickettsia. Restriction fragment length polymorphism (RFLP) and sequence analysis identified "Rickettsia amblyommii." This organism is not yet described or well studied, and its pathogenicity is unknown; however, investigations of the organism are warranted because of its high prevalence in A. americanum. This tick is extremely abundant at military training facilities in the south, central, and Mid-Atlantic United States, and many soldiers experience multiple concurrent tick bites. Bites by R. amblyommii-infected A. americanum may account for rates of SFG rickettsia seropositivity that are higher than reported rates of Rocky Mountain spotted fever (RMSF) cases from the same location. Seroconversion to SFG rickettsia following bites of A. americanum may suggest that R. amblyommii is infectious in humans. Subclinical infection in the numerous A. americanum tick bite victims could contaminate donated blood and compromise immunodeficient recipients. Detection of R. amblyommii in questing A. americanum larvae suggests transovarial transmission. The absence of R. rickettsii, the agent of RMSF, in A. americanum may be due to transovarial interference by R. amblyommii. The likelihood of pathogen transmission by larvae is magnified by their habit of mass attack. The very small size of the larvae is also a risk factor for pathogen transmission. High R. amblyommii prevalence in populations of A. americanum presage co-infection with other A. americanum-borne pathogens. A. americanum nymphs and adults from APG were found to be co-infected with R. amblyommii and Borrelia lonestari, Ehrlichia chaffeensis and Ehrlichia ewingii, respectively, and larval pools were infected with both R. amblyommii and B. lonestari. Co-infections can compound effects and complicate diagnosis of tick-borne disease.

  15. Caffeine Taste Signaling in Drosophila Larvae

    PubMed Central

    Apostolopoulou, Anthi A.; Köhn, Saskia; Stehle, Bernhard; Lutz, Michael; Wüst, Alexander; Mazija, Lorena; Rist, Anna; Galizia, C. Giovanni; Lüdke, Alja; Thum, Andreas S.

    2016-01-01

    The Drosophila larva has a simple peripheral nervous system with a comparably small number of sensory neurons located externally at the head or internally along the pharynx to assess its chemical environment. It is assumed that larval taste coding occurs mainly via external organs (the dorsal, terminal, and ventral organ). However, the contribution of the internal pharyngeal sensory organs has not been explored. Here we find that larvae require a single pharyngeal gustatory receptor neuron pair called D1, which is located in the dorsal pharyngeal sensilla, in order to avoid caffeine and to associate an odor with caffeine punishment. In contrast, caffeine-driven reduction in feeding in non-choice situations does not require D1. Hence, this work provides data on taste coding via different receptor neurons, depending on the behavioral context. Furthermore, we show that the larval pharyngeal system is involved in bitter tasting. Using ectopic expressions, we show that the caffeine receptor in neuron D1 requires the function of at least four receptor genes: the putative co-receptors Gr33a, Gr66a, the putative caffeine-specific receptor Gr93a, and yet unknown additional molecular component(s). This suggests that larval taste perception is more complex than previously assumed already at the sensory level. Taste information from different sensory organs located outside at the head or inside along the pharynx of the larva is assembled to trigger taste guided behaviors. PMID:27555807

  16. Caffeine Taste Signaling in Drosophila Larvae.

    PubMed

    Apostolopoulou, Anthi A; Köhn, Saskia; Stehle, Bernhard; Lutz, Michael; Wüst, Alexander; Mazija, Lorena; Rist, Anna; Galizia, C Giovanni; Lüdke, Alja; Thum, Andreas S

    2016-01-01

    The Drosophila larva has a simple peripheral nervous system with a comparably small number of sensory neurons located externally at the head or internally along the pharynx to assess its chemical environment. It is assumed that larval taste coding occurs mainly via external organs (the dorsal, terminal, and ventral organ). However, the contribution of the internal pharyngeal sensory organs has not been explored. Here we find that larvae require a single pharyngeal gustatory receptor neuron pair called D1, which is located in the dorsal pharyngeal sensilla, in order to avoid caffeine and to associate an odor with caffeine punishment. In contrast, caffeine-driven reduction in feeding in non-choice situations does not require D1. Hence, this work provides data on taste coding via different receptor neurons, depending on the behavioral context. Furthermore, we show that the larval pharyngeal system is involved in bitter tasting. Using ectopic expressions, we show that the caffeine receptor in neuron D1 requires the function of at least four receptor genes: the putative co-receptors Gr33a, Gr66a, the putative caffeine-specific receptor Gr93a, and yet unknown additional molecular component(s). This suggests that larval taste perception is more complex than previously assumed already at the sensory level. Taste information from different sensory organs located outside at the head or inside along the pharynx of the larva is assembled to trigger taste guided behaviors.

  17. Caffeine Taste Signaling in Drosophila Larvae.

    PubMed

    Apostolopoulou, Anthi A; Köhn, Saskia; Stehle, Bernhard; Lutz, Michael; Wüst, Alexander; Mazija, Lorena; Rist, Anna; Galizia, C Giovanni; Lüdke, Alja; Thum, Andreas S

    2016-01-01

    The Drosophila larva has a simple peripheral nervous system with a comparably small number of sensory neurons located externally at the head or internally along the pharynx to assess its chemical environment. It is assumed that larval taste coding occurs mainly via external organs (the dorsal, terminal, and ventral organ). However, the contribution of the internal pharyngeal sensory organs has not been explored. Here we find that larvae require a single pharyngeal gustatory receptor neuron pair called D1, which is located in the dorsal pharyngeal sensilla, in order to avoid caffeine and to associate an odor with caffeine punishment. In contrast, caffeine-driven reduction in feeding in non-choice situations does not require D1. Hence, this work provides data on taste coding via different receptor neurons, depending on the behavioral context. Furthermore, we show that the larval pharyngeal system is involved in bitter tasting. Using ectopic expressions, we show that the caffeine receptor in neuron D1 requires the function of at least four receptor genes: the putative co-receptors Gr33a, Gr66a, the putative caffeine-specific receptor Gr93a, and yet unknown additional molecular component(s). This suggests that larval taste perception is more complex than previously assumed already at the sensory level. Taste information from different sensory organs located outside at the head or inside along the pharynx of the larva is assembled to trigger taste guided behaviors. PMID:27555807

  18. Drosophila larvae: Thermal ecology in changing environments

    NASA Astrophysics Data System (ADS)

    Wang, George

    Temperature affects almost all aspects of life. Although much work has been done to assess the impact of temperature on organismal performance, relatively little is known about how organisms behaviorally regulate temperature, how these behaviors effect population fitness, or how changing climate may interact with these behaviors. I explore these questions with the model system Drosophila larvae. Larvae are small, with a low thermal mass and limited capacity for physiological thermoregulation. Mortality is generally high in larvae, with large potential impacts on population growth rate. Thus behavioral thermoregulation in larvae should be of critical selective importance. I present a review of the current knowledge of Drosophila thermal preference. I describe quantifiable thermoregulatory behaviors ( TMV and TW) unique to larvae. I show interspecific variation of these behaviors in Drosophila melanogaster and several close relatives, and intraspecific variation between populations collected from different environments. I also investigate these behaviors in two mutant lines, ssa and biz, to investigate the genetic basis of these behaviors. I show that larval thermoregulatory systems are independent of those of adults. Further these thermoregulatory behaviors differ between two sister species, D. yakuba and D. santomea. Although these two species readily hybridize in laboratory conditions, very few hybrids are observed in the field. The surprising result that hybrids of D. yakuba and D. santomea seem to inherit TMV from D. yakuba suggests a novel extrinsic isolation mechanism between the two species. I explore how fitness is the result of the interaction between genetics and the environment. I utilize Monte Carlo simulation to show how non-linear norms of reaction generate variation in populations even in the absence of behavior or epigenetic evolutionary mechanisms. Finally I investigate the global distribution of temperatures in which these organisms exist using

  19. Exposure to Low Irradiances Favors the Synthesis of 9-cis β,β-Carotene in Dunaliella salina (Teod.)1

    PubMed Central

    Orset, Sandra Charlotte; Young, Andrew John

    2000-01-01

    We examined the effect of irradiance on the synthesis of β-carotene and its isomers by Dunaliella salina. Growth irradiance had a marked effect both on growth of the alga (which was suppressed at both low and high irradiances) and on the accumulation of β-carotene. The accumulation of β-carotene but not α-carotene was closely linked to an increase in irradiance. Growth at low irradiances (20–50 μmol m−2 s−1) promoted a high ratio of 9-cis to all-trans β-carotene (>2:1), while exposure to high irradiances (200–1,250 μmol m−2 s−1) resulted in a large reduction in this ratio (to <0.45:1). A similar pattern was seen for the geometric isomers of α-carotene, with exposure to low irradiance favoring the accumulation of the 9-cis form. The carotenoid biosynthesis inhibitors 4-chloro-5(methylamino)-2-(α-α-α-trifluoro-m-tolyl)-3-(sH)-pyridazinone and 2-(4-chlorophenylthio)triethylamine caused the accumulation of the precursors phytoene and lycopene, respectively, in D. salina. High-performance liquid chromatography and infrared analysis showed that phytoene adopted the 15-cis and all-trans forms (as in higher plants), and that lycopene primarily adopted the all-trans form. This indicates that isomerization of β-carotene takes place during or after cyclization. PMID:10677453

  20. Evaluation of Culture Conditions to Obtain Fatty Acids from Saline Microalgae Species: Dunaliella salina, Sinecosyfis sp., and Chroomonas sp.

    PubMed

    Castilla Casadiego, D A; Albis Arrieta, A R; Angulo Mercado, E R; Cervera Cahuana, S J; Baquero Noriega, K S; Suárez Escobar, A F; Morales Avendaño, E D

    2016-01-01

    The use of the saline microalgae, Dunaliella salina, Sinecosyfis sp., and Chroomonas sp., was explored as an alternative source for the production of fatty acids using fertilizer and glycerol as culture media. The nutrient medium used contained "Nutrifoliar," a commercial fertilizer, and/or glycerol, in natural sea water. The microalgae were placed in cultures with different conditions. The parameters that favored the largest production of fatty acids were 24 hours of agitation and illumination, 1620 L/day of air supply, 2.25 L of air/min, and a temperature of 32°C using "Nutrifoliar" as the culture media. Results indicated that, from 3 g of microalgae in wet base of Chroomonas sp., 54.43 mg of oil was produced. The chromatographic characterization of oil obtained revealed the presence of essential fatty acids such as 9,12,15-octadecatrienoic acid (omega-3) and 4,7,10-hexadecatrienoic acid (omega-6) from the species Dunaliella salina. On the other hand, 9,12-octadecadienoic acid (omega-6) and cis-11-eicosenoic acid (omega-9) were identified from the species Chroomonas sp. The temperature variations played an important role in the velocity of growth or the production of the algae biomass, the amount of oil, and the ability to produce fatty acids.

  1. Evaluation of Culture Conditions to Obtain Fatty Acids from Saline Microalgae Species: Dunaliella salina, Sinecosyfis sp., and Chroomonas sp.

    PubMed

    Castilla Casadiego, D A; Albis Arrieta, A R; Angulo Mercado, E R; Cervera Cahuana, S J; Baquero Noriega, K S; Suárez Escobar, A F; Morales Avendaño, E D

    2016-01-01

    The use of the saline microalgae, Dunaliella salina, Sinecosyfis sp., and Chroomonas sp., was explored as an alternative source for the production of fatty acids using fertilizer and glycerol as culture media. The nutrient medium used contained "Nutrifoliar," a commercial fertilizer, and/or glycerol, in natural sea water. The microalgae were placed in cultures with different conditions. The parameters that favored the largest production of fatty acids were 24 hours of agitation and illumination, 1620 L/day of air supply, 2.25 L of air/min, and a temperature of 32°C using "Nutrifoliar" as the culture media. Results indicated that, from 3 g of microalgae in wet base of Chroomonas sp., 54.43 mg of oil was produced. The chromatographic characterization of oil obtained revealed the presence of essential fatty acids such as 9,12,15-octadecatrienoic acid (omega-3) and 4,7,10-hexadecatrienoic acid (omega-6) from the species Dunaliella salina. On the other hand, 9,12-octadecadienoic acid (omega-6) and cis-11-eicosenoic acid (omega-9) were identified from the species Chroomonas sp. The temperature variations played an important role in the velocity of growth or the production of the algae biomass, the amount of oil, and the ability to produce fatty acids. PMID:27376085

  2. Evaluation of Culture Conditions to Obtain Fatty Acids from Saline Microalgae Species: Dunaliella salina, Sinecosyfis sp., and Chroomonas sp.

    PubMed Central

    Castilla Casadiego, D. A.; Albis Arrieta, A. R.; Angulo Mercado, E. R.; Cervera Cahuana, S. J.; Baquero Noriega, K. S.; Suárez Escobar, A. F.; Morales Avendaño, E. D.

    2016-01-01

    The use of the saline microalgae, Dunaliella salina, Sinecosyfis sp., and Chroomonas sp., was explored as an alternative source for the production of fatty acids using fertilizer and glycerol as culture media. The nutrient medium used contained “Nutrifoliar,” a commercial fertilizer, and/or glycerol, in natural sea water. The microalgae were placed in cultures with different conditions. The parameters that favored the largest production of fatty acids were 24 hours of agitation and illumination, 1620 L/day of air supply, 2.25 L of air/min, and a temperature of 32°C using “Nutrifoliar” as the culture media. Results indicated that, from 3 g of microalgae in wet base of Chroomonas sp., 54.43 mg of oil was produced. The chromatographic characterization of oil obtained revealed the presence of essential fatty acids such as 9,12,15-octadecatrienoic acid (omega-3) and 4,7,10-hexadecatrienoic acid (omega-6) from the species Dunaliella salina. On the other hand, 9,12-octadecadienoic acid (omega-6) and cis-11-eicosenoic acid (omega-9) were identified from the species Chroomonas sp. The temperature variations played an important role in the velocity of growth or the production of the algae biomass, the amount of oil, and the ability to produce fatty acids. PMID:27376085

  3. Non-photochemical quenching in cryptophyte alga Rhodomonas salina is located in chlorophyll a/c antennae.

    PubMed

    Kaňa, Radek; Kotabová, Eva; Sobotka, Roman; Prášil, Ondřej

    2012-01-01

    Photosynthesis uses light as a source of energy but its excess can result in production of harmful oxygen radicals. To avoid any resulting damage, phototrophic organisms can employ a process known as non-photochemical quenching (NPQ), where excess light energy is safely dissipated as heat. The mechanism(s) of NPQ vary among different phototrophs. Here, we describe a new type of NPQ in the organism Rhodomonas salina, an alga belonging to the cryptophytes, part of the chromalveolate supergroup. Cryptophytes are exceptional among photosynthetic chromalveolates as they use both chlorophyll a/c proteins and phycobiliproteins for light harvesting. All our data demonstrates that NPQ in cryptophytes differs significantly from other chromalveolates - e.g. diatoms and it is also unique in comparison to NPQ in green algae and in higher plants: (1) there is no light induced xanthophyll cycle; (2) NPQ resembles the fast and flexible energetic quenching (qE) of higher plants, including its fast recovery; (3) a direct antennae protonation is involved in NPQ, similar to that found in higher plants. Further, fluorescence spectroscopy and biochemical characterization of isolated photosynthetic complexes suggest that NPQ in R. salina occurs in the chlorophyll a/c antennae but not in phycobiliproteins. All these results demonstrate that NPQ in cryptophytes represents a novel class of effective and flexible non-photochemical quenching.

  4. Induced carotenoid accumulation in Dunaliella salina and Tetraselmis suecica by plant hormones and UV-C radiation.

    PubMed

    Ahmed, Faruq; Fanning, Kent; Netzel, Michael; Schenk, Peer M

    2015-11-01

    Carotenoids prevent different degenerative diseases and improve human health. Microalgae are commercially exploited for carotenoids, including astaxanthin and β-carotene. Two commercially important microalgae, Dunaliella salina and Tetraselmis suecica, were treated with plant hormones salicylic acid (SA) and methyl jasmonate (MJ), or by UV-C radiation (T. suecica only) and a combination thereof. Significant increases in total carotenoids were found for D. salina and T. suecica after treatment with MJ (10 μmol/L) and SA (70-250 μmol/L), respectively. T. suecica also had significant increases in total carotenoids following UV-C radiation compared to control cultures. Among the carotenoids, lutein was the highest induced carotenoid. A combination of these two treatments also showed a significant increase in total carotenoids and lutein for T. suecica, when compared to controls. Plant hormones and UV-C radiation may be useful tools for increasing carotenoid accumulation in green microalgae although the responses are species- and dose-specific and should be trialed in medium to large scale to explore commercial production. PMID:26201492

  5. Induced carotenoid accumulation in Dunaliella salina and Tetraselmis suecica by plant hormones and UV-C radiation.

    PubMed

    Ahmed, Faruq; Fanning, Kent; Netzel, Michael; Schenk, Peer M

    2015-11-01

    Carotenoids prevent different degenerative diseases and improve human health. Microalgae are commercially exploited for carotenoids, including astaxanthin and β-carotene. Two commercially important microalgae, Dunaliella salina and Tetraselmis suecica, were treated with plant hormones salicylic acid (SA) and methyl jasmonate (MJ), or by UV-C radiation (T. suecica only) and a combination thereof. Significant increases in total carotenoids were found for D. salina and T. suecica after treatment with MJ (10 μmol/L) and SA (70-250 μmol/L), respectively. T. suecica also had significant increases in total carotenoids following UV-C radiation compared to control cultures. Among the carotenoids, lutein was the highest induced carotenoid. A combination of these two treatments also showed a significant increase in total carotenoids and lutein for T. suecica, when compared to controls. Plant hormones and UV-C radiation may be useful tools for increasing carotenoid accumulation in green microalgae although the responses are species- and dose-specific and should be trialed in medium to large scale to explore commercial production.

  6. Interactions among Drosophila larvae before and during collision

    PubMed Central

    Otto, Nils; Risse, Benjamin; Berh, Dimitri; Bittern, Jonas; Jiang, Xiaoyi; Klämbt, Christian

    2016-01-01

    In populations of Drosophila larvae, both, an aggregation and a dispersal behavior can be observed. However, the mechanisms coordinating larval locomotion in respect to other animals, especially in close proximity and during/after physical contacts are currently only little understood. Here we test whether relevant information is perceived before or during larva-larva contacts, analyze its influence on behavior and ask whether larvae avoid or pursue collisions. Employing frustrated total internal reflection-based imaging (FIM) we first found that larvae visually detect other moving larvae in a narrow perceptive field and respond with characteristic escape reactions. To decipher larval locomotion not only before but also during the collision we utilized a two color FIM approach (FIM2c), which allowed to faithfully extract the posture and motion of colliding animals. We show that during collision, larval locomotion freezes and sensory information is sampled during a KISS phase (german: Kollisions Induziertes Stopp Syndrom or english: collision induced stop syndrome). Interestingly, larvae react differently to living, dead or artificial larvae, discriminate other Drosophila species and have an increased bending probability for a short period after the collision terminates. Thus, Drosophila larvae evolved means to specify behaviors in response to other larvae. PMID:27511760

  7. Requirements for In Vitro Germination of Paenibacillus larvae Spores

    PubMed Central

    Alvarado, Israel; Phui, Andy; Elekonich, Michelle M.

    2013-01-01

    Paenibacillus larvae is the causative agent of American foulbrood (AFB), a disease affecting honey bee larvae. First- and second-instar larvae become infected when they ingest food contaminated with P. larvae spores. The spores then germinate into vegetative cells that proliferate in the midgut of the honey bee. Although AFB affects honey bees only in the larval stage, P. larvae spores can be distributed throughout the hive. Because spore germination is critical for AFB establishment, we analyzed the requirements for P. larvae spore germination in vitro. We found that P. larvae spores germinated only in response to l-tyrosine plus uric acid under physiologic pH and temperature conditions. This suggests that the simultaneous presence of these signals is necessary for spore germination in vivo. Furthermore, the germination profiles of environmentally derived spores were identical to those of spores from a biochemically typed strain. Because l-tyrosine and uric acid are the only required germinants in vitro, we screened amino acid and purine analogs for their ability to act as antagonists of P. larvae spore germination. Indole and phenol, the side chains of tyrosine and tryptophan, strongly inhibited P. larvae spore germination. Methylation of the N-1 (but not the C-3) position of indole eliminated its ability to inhibit germination. Identification of the activators and inhibitors of P. larvae spore germination provides a basis for developing new tools to control AFB. PMID:23264573

  8. Interactions among Drosophila larvae before and during collision.

    PubMed

    Otto, Nils; Risse, Benjamin; Berh, Dimitri; Bittern, Jonas; Jiang, Xiaoyi; Klämbt, Christian

    2016-01-01

    In populations of Drosophila larvae, both, an aggregation and a dispersal behavior can be observed. However, the mechanisms coordinating larval locomotion in respect to other animals, especially in close proximity and during/after physical contacts are currently only little understood. Here we test whether relevant information is perceived before or during larva-larva contacts, analyze its influence on behavior and ask whether larvae avoid or pursue collisions. Employing frustrated total internal reflection-based imaging (FIM) we first found that larvae visually detect other moving larvae in a narrow perceptive field and respond with characteristic escape reactions. To decipher larval locomotion not only before but also during the collision we utilized a two color FIM approach (FIM(2c)), which allowed to faithfully extract the posture and motion of colliding animals. We show that during collision, larval locomotion freezes and sensory information is sampled during a KISS phase (german: Kollisions Induziertes Stopp Syndrom or english: collision induced stop syndrome). Interestingly, larvae react differently to living, dead or artificial larvae, discriminate other Drosophila species and have an increased bending probability for a short period after the collision terminates. Thus, Drosophila larvae evolved means to specify behaviors in response to other larvae.

  9. The Identification of Congeners and Aliens by Drosophila Larvae

    PubMed Central

    Del Pino, Francisco; Jara, Claudia; Pino, Luis; Medina-Muñoz, María Cristina; Alvarez, Eduardo; Godoy-Herrera, Raúl

    2015-01-01

    We investigated the role of Drosophila larva olfactory system in identification of congeners and aliens. We discuss the importance of these activities in larva navigation across substrates, and the implications for allocation of space and food among species of similar ecologies. Wild type larvae of cosmopolitan D. melanogaster and endemic D. pavani, which cohabit the same breeding sites, used species-specific volatiles to identify conspecifics and aliens moving toward larvae of their species. D. gaucha larvae, a sibling species of D. pavani that is ecologically isolated from D. melanogaster, did not respond to melanogaster odor cues. Similar to D. pavani larvae, the navigation of pavani female x gaucha male hybrids was influenced by conspecific and alien odors, whereas gaucha female x pavani male hybrid larvae exhibited behavior similar to the D. gaucha parent. The two sibling species exhibited substantial evolutionary divergence in processing the odor inputs necessary to identify conspecifics. Orco (Or83b) mutant larvae of D. melanogaster, which exhibit a loss of sense of smell, did not distinguish conspecific from alien larvae, instead moving across the substrate. Syn97CS and rut larvae of D. melanogaster, which are unable to learn but can smell, moved across the substrate as well. The Orco (Or83b), Syn97CS and rut loci are necessary to orient navigation by D. melanogaster larvae. Individuals of the Trana strain of D. melanogaster did not respond to conspecific and alien larval volatiles and therefore navigated randomly across the substrate. By contrast, larvae of the Til-Til strain used larval volatiles to orient their movement. Natural populations of D. melanogaster may exhibit differences in identification of conspecific and alien larvae. Larval locomotion was not affected by the volatiles. PMID:26313007

  10. The Identification of Congeners and Aliens by Drosophila Larvae.

    PubMed

    Del Pino, Francisco; Jara, Claudia; Pino, Luis; Medina-Muñoz, María Cristina; Alvarez, Eduardo; Godoy-Herrera, Raúl

    2015-01-01

    We investigated the role of Drosophila larva olfactory system in identification of congeners and aliens. We discuss the importance of these activities in larva navigation across substrates, and the implications for allocation of space and food among species of similar ecologies. Wild type larvae of cosmopolitan D. melanogaster and endemic D. pavani, which cohabit the same breeding sites, used species-specific volatiles to identify conspecifics and aliens moving toward larvae of their species. D. gaucha larvae, a sibling species of D. pavani that is ecologically isolated from D. melanogaster, did not respond to melanogaster odor cues. Similar to D. pavani larvae, the navigation of pavani female x gaucha male hybrids was influenced by conspecific and alien odors, whereas gaucha female x pavani male hybrid larvae exhibited behavior similar to the D. gaucha parent. The two sibling species exhibited substantial evolutionary divergence in processing the odor inputs necessary to identify conspecifics. Orco (Or83b) mutant larvae of D. melanogaster, which exhibit a loss of sense of smell, did not distinguish conspecific from alien larvae, instead moving across the substrate. Syn97CS and rut larvae of D. melanogaster, which are unable to learn but can smell, moved across the substrate as well. The Orco (Or83b), Syn97CS and rut loci are necessary to orient navigation by D. melanogaster larvae. Individuals of the Trana strain of D. melanogaster did not respond to conspecific and alien larval volatiles and therefore navigated randomly across the substrate. By contrast, larvae of the Til-Til strain used larval volatiles to orient their movement. Natural populations of D. melanogaster may exhibit differences in identification of conspecific and alien larvae. Larval locomotion was not affected by the volatiles.

  11. The Identification of Congeners and Aliens by Drosophila Larvae.

    PubMed

    Del Pino, Francisco; Jara, Claudia; Pino, Luis; Medina-Muñoz, María Cristina; Alvarez, Eduardo; Godoy-Herrera, Raúl

    2015-01-01

    We investigated the role of Drosophila larva olfactory system in identification of congeners and aliens. We discuss the importance of these activities in larva navigation across substrates, and the implications for allocation of space and food among species of similar ecologies. Wild type larvae of cosmopolitan D. melanogaster and endemic D. pavani, which cohabit the same breeding sites, used species-specific volatiles to identify conspecifics and aliens moving toward larvae of their species. D. gaucha larvae, a sibling species of D. pavani that is ecologically isolated from D. melanogaster, did not respond to melanogaster odor cues. Similar to D. pavani larvae, the navigation of pavani female x gaucha male hybrids was influenced by conspecific and alien odors, whereas gaucha female x pavani male hybrid larvae exhibited behavior similar to the D. gaucha parent. The two sibling species exhibited substantial evolutionary divergence in processing the odor inputs necessary to identify conspecifics. Orco (Or83b) mutant larvae of D. melanogaster, which exhibit a loss of sense of smell, did not distinguish conspecific from alien larvae, instead moving across the substrate. Syn97CS and rut larvae of D. melanogaster, which are unable to learn but can smell, moved across the substrate as well. The Orco (Or83b), Syn97CS and rut loci are necessary to orient navigation by D. melanogaster larvae. Individuals of the Trana strain of D. melanogaster did not respond to conspecific and alien larval volatiles and therefore navigated randomly across the substrate. By contrast, larvae of the Til-Til strain used larval volatiles to orient their movement. Natural populations of D. melanogaster may exhibit differences in identification of conspecific and alien larvae. Larval locomotion was not affected by the volatiles. PMID:26313007

  12. Differential responses of sexual and asexual Artemia to genotoxicity by a reference mutagen: Is the comet assay a reliable predictor of population level responses?

    PubMed

    Sukumaran, Sandhya; Grant, Alastair

    2013-05-01

    The impact of chronic genotoxicity to natural populations is always questioned due to their reproductive surplus. We used a comet assay to quantify primary DNA damage after exposure to a reference mutagen ethyl methane sulfonate in two species of crustacean with different reproductive strategies (sexual Artemia franciscana and asexual Artemia parthenogenetica). We then assessed whether this predicted individual performance and population growth rate over three generations. Artemia were exposed to different chronic concentrations (0.78mM, 1.01mM, 1.24mM and 1.48mM) of ethyl methane sulfonate from instar 1 onwards for 3 h, 24 h, 7 days, 14 days and 21 days and percentage tail DNA values were used for comparisons between species. The percentage tail DNA values showed consistently elevated values up to 7 days and showed a reduction from 14 days onwards in A. franciscana. Whilst in A. parthenogenetica such a reduction was evident on 21 days assessment. The values of percentage tail DNA after 21 days were compared with population level fitness parameters, growth, survival, fecundity and population growth rate to know whether primary DNA damage as measured by comet assay is a reliable biomarker. Substantial increase in tail DNA values was associated with substantial reductions in all the fitness parameters in the parental generation of A. franciscana and parental, F1 and F2 generations of A. parthenogenetica. So comet results were more predictive in asexual species over generations. These results pointed to the importance of predicting biomarker responses from multigenerational consequences considering life history traits and reproductive strategies in ecological risk assessments.

  13. Group 3 late embryogenesis abundant proteins from embryos of Artemia franciscana: structural properties and protective abilities during desiccation.

    PubMed

    Boswell, Leaf C; Menze, Michael A; Hand, Steven C

    2014-01-01

    Group 3 late embryogenesis abundant (LEA) proteins are highly hydrophilic, and their expression is associated with desiccation tolerance in both plants and animals. Here we show that two LEA proteins from embryos of Artemia franciscana, AfrLEA2 and AfrLEA3m, are intrinsically disordered in solution but upon desiccation gain secondary structure, as measured by circular dichroism. Trifluoroethanol and sodium dodecyl sulfate are both shown to induce α-helical structure in AfrLEA2 and AfrLEA3m. Bioinformatic predictions of secondary-structure content for both proteins correspond most closely to conformations measured in the dry state. Because some LEA proteins afford protection to desiccation-sensitive proteins during drying and subsequent rehydration, we tested for this capacity in AfrLEA2 and AfrLEA3m. The protective capacities vary, depending on the target enzyme. For the cytoplasmic enzyme lactate dehydrogenase, neither AfrLEA2 nor AfrLEA3m, with or without trehalose present, was able to afford protection better than that provided by bovine serum albumin (BSA) under the same conditions. However, for another cytoplasmic enzyme, phosphofructokinase, both AfrLEA2 and AfrLEA3m in the presence of trehalose were able to afford protection far greater than that provided by BSA with trehalose. Finally, for the mitochondrial enzyme citrate synthase, 400-μg/mL AfrLEA3m without trehalose provided significantly more protection than the same concentration of either AfrLEA2 or BSA. PMID:25244376

  14. Heat dissipation during long-term anoxia in Artemia franciscana embryos: identification and fate of metabolic fuels.

    PubMed

    Hand, S C

    1990-01-01

    Microcalorimetric measurements of brine shrimp embryos during 6 days of anoxia indicated that heat dissipation was rapidly suppressed to 2.7% of control (aerobic) values over the first 9 h. Energy flow continued to decline slowly to 31 microW.g dry mass-1 (0.4% of control) during the subsequent 5.5 days. Within 2 h after returning anoxic embryos to aerobic conditions, heat dissipation rose to 77% of control rates. The calorimetric/respirometric (CR) ratio across this 2-h recovery period increased steadily from -226 to -346 kJ.mol O2-1). Prior to the anoxic exposures, hydrated embryos were incubated aerobically for 10 h to insure full initiation of carbohydrate metabolism (CR ratio = -484 kJ.mol O2-1). During the 6-day asymptotic approach to a nearly ametabolic state, trehalose and glycogen levels declined 18% and 13%, respectively. The majority of this utilization occurred within the first three days. Thermochemical calculations showed that carbohydrate catabolism accounted for 84% of the total heat dissipation measured over the 6-day anoxic bout; only 3% of the heat could be explained by the catabolism of diguanosine tetraphosphate (Gp4G). Analyses of embryo extracts by high performance liquid chromatography indicated that multiple acid end products were accumulated. Lactate and propionate reached 4.5 mM and 1.0 mM, respectively, but these compounds did not account quantitatively for the amount of carbohydrate utilized. However, the largest chromatographic peak that accumulated under anoxia has not been successfully identified. Fumarate and pyruvate levels decreased as anoxia proceeded. Thus, a perceptible energy flow in Artemia franciscana embryos still remained after 6 days of anoxia.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2292613

  15. Profiles of nuclear and mitochondrial encoded mRNAs in developing and quiescent embryos of Artemia franciscana.

    PubMed

    Hardewig, I; Anchordoguy, T J; Crawford, D L; Hand, S C

    1996-05-24

    Embryos of the brine shrimp Artemia franciscana are able to withstand long bouts of environmental anoxia by entering a quiescent state during which metabolism is greatly depressed. Recent evidence supports a global arrest of protein synthesis during quiescence. In this study we measured the amounts of mRNA for a mitochondrial-encoded subunit of cytochrome c oxidase (COX I) and for nuclear-encoded actin during aerobic development, anaerobiosis, and aerobic acidosis (artificial quiescence imposed by intracellular acidification under aerobic conditions). The levels of both COX I and actin transcripts increased significantly during aerobic development. COX I mRNA levels were tightly correlated with previous measures of COX catalytic activity, which suggests that COX synthesis could be regulated by message concentration during aerobic development. The ontogenetic increase for these mRNAs was blocked by anoxia and aerobic acidosis. Importantly, the levels of COX I and actin mRNA did not decline appreciably during the 6 h bouts of quiescence, even though protein synthesis is acutely arrested by these same treatments. Thus, the constancy of mRNA levels during quiescence indicate that reduced protein synthesis is not caused by message limitation, but rather, is likely controlled at the translational level. One advantage of this regulatory mechanism is the conservation of mRNA molecules during quiescence, which would potentially favor a quick resumption of translation as soon as oxygen is returned to the embryos. Finally, because anoxia and aerobic acidosis are both characterized by acidic intracellular pH, the reduction in pH may serve, directly or indirectly, as one signal regulating levels of mRNA in this embryo during quiescence. PMID:8817476

  16. Mitochondrial mRNA stability and polyadenylation during anoxia-induced quiescence in the brine shrimp Artemia franciscana.

    PubMed

    Eads, Brian D; Hand, Steven C

    2003-10-01

    Polyadenylation of messenger RNA is known to be an important mechanism for regulating mRNA stability in a variety of systems, including bacteria, chloroplasts and plant mitochondria. By comparison, little is known about the role played by polyadenylation in animal mitochondrial gene expression. We have used embryos of the brine shrimp Artemia franciscana to test hypotheses regarding message stability and polyadenylation under conditions simulating anoxia-induced quiescence. In response to anoxia, these embryos undergo a profound and acute metabolic downregulation, characterized by a steep drop in intracellular pH (pH(i)) and ATP levels. Using dot blots of total mitochondrial RNA, we show that during in organello incubations both O(2) deprivation and acidic pH (pH 6.4) elicit increases in half-lives of selected mitochondrial transcripts on the order of five- to tenfold or more, relative to normoxic controls at pH 7.8. Polyadenylation of these transcripts was measured under the same incubation conditions using a reverse transcriptase-polymerase chain reaction (RT-PCR)-based assay. The results demonstrate that low pH and anoxia promote significant deadenylation of the stabilized transcripts in several cases, measured either as change over time in the amount of polyadenylation within a given size class of poly(A)(+) tail, or as the total amount of polyadenylation at the endpoint of the incubation. This study is the first direct demonstration that for a metazoan mitochondrion, polyadenylation is associated with destabilized mRNA. This pattern has also been demonstrated in bacteria, chloroplasts and plant mitochondria and may indicate a conserved mechanism for regulating message half-life that differs from the paradigm for eukaryotic cytoplasm, where increased mRNA stability is associated with polyadenylation. PMID:12966060

  17. Bird migratory flyways influence the phylogeography of the invasive brine shrimp Artemia franciscana in its native American range

    PubMed Central

    Muñoz, Joaquín; Amat, Francisco; Green, Andy J.; Figuerola, Jordi

    2013-01-01

    Since Darwin’s time, waterbirds have been considered an important vector for the dispersal of continental aquatic invertebrates. Bird movements have facilitated the worldwide invasion of the American brine shrimp Artemia franciscana, transporting cysts (diapausing eggs), and favouring rapid range expansions from introduction sites. Here we address the impact of bird migratory flyways on the population genetic structure and phylogeography of A. franciscana in its native range in the Americas. We examined sequence variation for two mitochondrial gene fragments (COI and 16S for a subset of the data) in a large set of population samples representing the entire native range of A. franciscana. Furthermore, we performed Mantel tests and redundancy analyses (RDA) to test the role of flyways, geography and human introductions on the phylogeography and population genetic structure at a continental scale. A. franciscana mitochondrial DNA was very diverse, with two main clades, largely corresponding to Pacific and Atlantic populations, mirroring American bird flyways. There was a high degree of regional endemism, with populations subdivided into at least 12 divergent, geographically restricted and largely allopatric mitochondrial lineages, and high levels of population structure (ΦST of 0.92), indicating low ongoing gene flow. We found evidence of human-mediated introductions in nine out of 39 populations analysed. Once these populations were removed, Mantel tests revealed a strong association between genetic variation and geographic distance (i.e., isolation-by-distance pattern). RDA showed that shared bird flyways explained around 20% of the variance in genetic distance between populations and this was highly significant, once geographic distance was controlled for. The variance explained increased to 30% when the factor human introduction was included in the model. Our findings suggest that bird-mediated transport of brine shrimp propagules does not result in substantial

  18. Chromium (VI) induced oxidative stress in halotolerant alga Dunaliella salina and D. tertiolecta isolated from sambhar salt lake of Rajasthan (India).

    PubMed

    Arun, N; Vidyalaxmi; Singh, D P

    2014-01-01

    Chromium (Cr) is one of the most serious pollutants in aquatic systems. This study was performed to understand the effect of Cr (VI) on halophilic algal strains of D. salina and D. tertiolecta. The results revealed good tolerance of D. salina towards chromium (VI) up to 8 ppm concentration, whereas tolerance level in D. tertiolecta was up to 2 ppm concentration. Cr (VI) not only inhibited the growth of D. tertiolecta, but also showed increased inhibition in the level of photosynthetic pigments, protein and carbohydrate. Results have revealed that chromium (VI) induced higher increase in lipid peroxidation and H2O2 production in D. tertiolecta than the D. salina, particularly at higher concentration of chromium (VI). Chromium (VI) induced increase in the rate of RNO bleaching, loss of pigments and thiol (-SH) group was relatively higher in D. tertiolecta than the D. salina, which is indicating that D. tertiolecta was prone to Cr (VI) induced oxidative stress. Results on RNO bleaching in the presence of radical quenchers suggested that OH° radical played an important role in the chromium (VI)-induced general oxidative stress in D. tertiolecta. PMID:25535718

  19. Chromium (VI) induced oxidative stress in halotolerant alga Dunaliella salina and D. tertiolecta isolated from sambhar salt lake of Rajasthan (India).

    PubMed

    Arun, N; Vidyalaxmi; Singh, D P

    2014-01-01

    Chromium (Cr) is one of the most serious pollutants in aquatic systems. This study was performed to understand the effect of Cr (VI) on halophilic algal strains of D. salina and D. tertiolecta. The results revealed good tolerance of D. salina towards chromium (VI) up to 8 ppm concentration, whereas tolerance level in D. tertiolecta was up to 2 ppm concentration. Cr (VI) not only inhibited the growth of D. tertiolecta, but also showed increased inhibition in the level of photosynthetic pigments, protein and carbohydrate. Results have revealed that chromium (VI) induced higher increase in lipid peroxidation and H2O2 production in D. tertiolecta than the D. salina, particularly at higher concentration of chromium (VI). Chromium (VI) induced increase in the rate of RNO bleaching, loss of pigments and thiol (-SH) group was relatively higher in D. tertiolecta than the D. salina, which is indicating that D. tertiolecta was prone to Cr (VI) induced oxidative stress. Results on RNO bleaching in the presence of radical quenchers suggested that OH° radical played an important role in the chromium (VI)-induced general oxidative stress in D. tertiolecta.

  20. Equipment for transporting live black fly larvae (Diptera: Simuliiae)

    USGS Publications Warehouse

    Tarshis, I.B.; Adkins, T.R.

    1971-01-01

    In studies relating to the biology and ecology of black flies, live larvae of at least 70 species of Simuliidae have been collected from their natural breeding sites and transported in containers with nonagitated water for short distances to the laboratory. One of us (Tarshis 1966) found, however, that even small numbers of simuliid larvae cannot survive in containers with nonagitated water for more than 6 hr. Additionally, when massive numbers of larvae are introduced into transport containers in which the water is not agitated, the larvae perish because they become entangled within the masses of silken threads they emit whenever disturbed (Tarshis and Neil 1970). Therefore, when transporting larvae long distances or when transporting large numbers of larvae any distance, it is essential to agitate the water in the transport containers.

  1. Validation of daily increments in otoliths of northern squawfish larvae

    USGS Publications Warehouse

    Wertheimer, R.H.; Barfoot, C.A.

    1998-01-01

    Otoliths from laboratory-reared northern squawfish, Ptychocheilus oregonensis, larvae were examined to determine the periodicity of increment deposition. Increment deposition began in both sagittae and lapilli after hatching. Reader counts indicated that increment formation was daily in sagittae of 1-29-day-old larvae. However, increment counts from lapilli were significantly less than the known ages of northern squawfish larvae, possibly because some increments were not detectable. Otolith readability and age agreement among readers were greatest for young (<11 days) northern squawfish larvae. This was primarily because a transitional zone of low-contrast material began forming in otoliths of 8-11-day-old larvae and persisted until approximately 20 days after hatching. Formation of the transition zone appeared to coincide with the onset of exogenous feeding and continued through yolk sac absorption. Our results indicate that aging wild-caught northern squawfish larvae using daily otolith increment counts is possible.

  2. Fate of pharmaceuticals and pesticides in fly larvae composting.

    PubMed

    Lalander, C; Senecal, J; Gros Calvo, M; Ahrens, L; Josefsson, S; Wiberg, K; Vinnerås, B

    2016-09-15

    A novel and efficient organic waste management strategy currently gaining great attention is fly larvae composting. High resource recovery efficiency can be achieved in this closed-looped system, but pharmaceuticals and pesticides in waste could potentially accumulate in every loop of the treatment system and spread to the environment. This study evaluated the fate of three pharmaceuticals (carbamazepine, roxithromycin, trimethoprim) and two pesticides (azoxystrobin, propiconazole) in a fly larvae composting system and in a control treatment with no larvae. It was found that the half-life of all five substances was shorter in the fly larvae compost (<10% of control) and no bioaccumulation was detected in the larvae. Fly larvae composting could thus impede the spread of pharmaceuticals and pesticides into the environment.

  3. Analysis of feeding behavior of Drosophila larvae on solid food.

    PubMed

    Shen, Ping

    2012-05-01

    The food responses of Drosophila larvae offer an excellent opportunity to study the genetic and neural regulation of feeding behavior. Compared with fed larvae, hungry larvae are more likely to display aggressive foraging, rapid food intake, compensatory feeding, and stress-resistant food procurement. Behavioral assays have been developed to quantitatively assess particular aspects of the hunger-driven food response. In combination, these assays help define the specific role of signaling molecules or neurons in the regulation of feeding behavior in foraging larvae. This protocol is designed for quantitative assessment of the willingness of individual larvae to procure solid food under different energy states. It provides a simple and reliable way to measure the graded modification of the baseline feeding rate of larvae as the period of food deprivation is increased. The test is applicable to routine functional testing and larger-scale screening of genetic mutations and biologics that might affect food consumption.

  4. Microsporidium Infecting Anopheles supepictus (Diptera: Culicidae) Larvae

    PubMed Central

    Omrani, Seyed-Mohammad; Moosavi, Seyedeh-Fatemeh; Manouchehri, Kourosh

    2016-01-01

    Background: Microsporidia are known to infect a wide variety of animals including mosquitoes (Diptera: Culicidae). In a recent study on the mosquito fauna of Chahar Mahal and Bakhtiari Province, at the central western part of Iran, a few larvae of Anopheles superpictus were infected with a microsporidium-resembled microorganism. Current investigation deals with the identification of the responsible microorganism at the genus level. Methods: Fresh infected larvae were collected from the field. After determining the species identity they were dissected to extract their infective contents. Wet preparations were checked for general appearance and the size of the pathogenic microorganism. Fixed preparations were stained with Geimsa and Ryan-Blue modified Trichrome techniques to visualize further morphological characters. The obtained light microscopy data were used in the identification process. Results: The infected larvae were bulged by a whitish material filling the involved segments corresponding to a microsporidium infection. Bottle-shaped semioval spores ranged 4.33±0.19×2.67±0.12 and 4.18±0.43×2.45±0.33 micron in wet and fixed preparations, respectively. They were mostly arranged in globular structures comprised of 8 spores. These data was in favor of a species from the genus Parathelohania in the family Ambliosporidae. Conclusion: This is the first report of a microsporidium infection in An. superpictus. The causative agent is diagnosed as a member of the genus Parathelohania. Further identification down to the species level needs to determine its ultrastructural characteristics and the comparative analysis of ss rRNA sequence data. It is also necessary to understand the detail of the components of the transmission cycle. PMID:27308299

  5. Larvae of hydromanicus (insecta: trichoptera: hydropsychidae) from Thailand.

    PubMed

    Prommi, Taeng On; Permkam, Surakrai

    2015-01-29

    Larvae of only 2 of the 13 species of Hydromanicus known from Thailand have been described previously. In this research, the "metamorphotype method" was used to associate yet-unidentifiable larvae and pupae with their identifiable adults: Pupal identifications were based on genitalic features in common with described adults, and larvae were associated with the pupae. Herein, the final larval instar of Hydromanicus malayanus, H. abiud and H. inferior are described and illustrated. 

  6. Toxicity of phenol on Macrobrachium rosenbergii (de Man) eggs, larvae, and post-larvae

    SciTech Connect

    Law, A.T.; Yeo, M.E.

    1997-03-01

    Literature on the toxicities of phenol on aquatic organisms is very limited. USEPA reported that the acute and chronic toxicities of phenol to freshwater aquatic life occur at concentrations as low as 10.2 mg/L and 2.56 mg/L, respectively. While for the saltwater aquatic life the acute toxicity occurs at concentrations as low as 5.8 mg/L. No data are available for the chronic toxicity of phenol to saltwater aquatic life. Sublethal concentrations of phenol have significant effects on the physiological and histological processes of the aquatic organisms: such as gill necrosis; destruction of erythrocyte cells; inhibition of sexual activities; suppression on growth and reduction of resistance to diseases. Macrobrachium rosenbergii(de Man) is the sole freshwater prawn cultured in Malaysia. Occasionally, the hatcheries are unable to produce the post-larvae because of undefined pollutants present in the water supplies. It has been observed that the use of cracked fiberglass tanks for larvae rearing is correlated with high mortality. This high mortality is probably due to the toxicity of the phenolic compounds which are leached out from the fiber glass tank into the water. This study was undertaken to evaluate the toxicity of phenol on eggs, larvae and post-larvae of M. rosenbergii and to set the water quality criteria of phenol for the said species. 16 refs., 3 tabs.

  7. Structure and occurrence of cyphonautes larvae (bryozoa, ectoprocta).

    PubMed

    Nielsen, Claus; Worsaae, Katrine

    2010-09-01

    We have studied larvae of the freshwater ctenostome Hislopia malayensis with scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), and LM of serial sections. Some additional observations on larvae of M. membranacea using SEM and CLSM are also reported. The overall configuration of muscles, nerves, and cilia of the two larvae are identical. However, the larva of H. malayensis is much smaller than that of M. membranacea, which may explain most of the differences observed. Although all major nerves and muscle strands are present in H. malayensis, they are generally composed of fewer fibers. The H. malayensis larva lacks the anterior and posterior intervalve cilia. Its pyriform organ is unciliated with only a small central depression. The adhesive epithelium is not invaginated as an adhesive sac and lacks the large muscles interpreted as adhesive sac muscles in the M. membranacea larva. The velum carries two rows of ciliated cells, though the lower "row" consists of only one or two cells. Both rows of ciliated cells are innervated by nerves, which have not been detected in the M. membranacea larva. The ciliated ridge of H. malayensis lacks the frontal cilia. The planktotrophic cyphonautes larvae in a number of ctenostome clades and in the "basal" cheilostome clade Malacostega (and probably in the earliest cheilostomes) support the idea that the cyphonautes larva is the ancestral larval type of the Eurystomata. It may even represent the ancestral larval type of the bryozoans (= ectoprocts).

  8. A Madurella mycetomatis Grain Model in Galleria mellonella Larvae

    PubMed Central

    Kloezen, Wendy; van Helvert-van Poppel, Marilyn; Fahal, Ahmed H.; van de Sande, Wendy W. J.

    2015-01-01

    Eumycetoma is a chronic granulomatous subcutaneous infectious disease, endemic in tropical and subtropical regions and most commonly caused by the fungus Madurella mycetomatis. Interestingly, although grain formation is key in mycetoma, its formation process and its susceptibility towards antifungal agents are not well understood. This is because grain formation cannot be induced in vitro; a mammalian host is necessary to induce its formation. Until now, invertebrate hosts were never used to study grain formation in M. mycetomatis. In this study we determined if larvae of the greater wax moth Galleria mellonella could be used to induce grain formation when infected with M. mycetomatis. Three different M. mycetomatis strains were selected and three different inocula for each strain were used to infect G. mellonella larvae, ranging from 0.04 mg/larvae to 4 mg/larvae. Larvae were monitored for 10 days. It appeared that most larvae survived the lowest inoculum, but at the highest inoculum all larvae died within the 10 day observation period. At all inocula tested, grains were formed within 4 hours after infection. The grains produced in the larvae resembled those formed in human and in mammalian hosts. In conclusion, the M. mycetomatis grain model in G. mellonella larvae described here could serve as a useful model to study the grain formation and therapeutic responses towards antifungal agents in the future. PMID:26173126

  9. Foraging by food deprived larvae of Neobellieria bullata (Diptera: Sarcophagidae).

    PubMed

    Christopherson, C; Gibo, D L

    1997-01-01

    Traditional entomological methods of estimating postmortem interval from developmental stages of fly larvae associated with the body are based on the premise that older larvae are not recruited from the surrounding environment. We found that food deprived second and third instar larvae of the fleshfly, Neobellieria bullata Parker, can locate beef liver over a distance of 33 cm, apparently by using chemical cues, and can crawl to the food within 90 min. The implications of these results are discussed with respect to methods of estimating postmortem interval by calculating rates of fly larvae development.

  10. A Model of Drosophila Larva Chemotaxis

    PubMed Central

    Davies, Alex; Louis, Matthieu; Webb, Barbara

    2015-01-01

    Detailed observations of larval Drosophila chemotaxis have characterised the relationship between the odour gradient and the runs, head casts and turns made by the animal. We use a computational model to test whether hypothesised sensorimotor control mechanisms are sufficient to account for larval behaviour. The model combines three mechanisms based on simple transformations of the recent history of odour intensity at the head location. The first is an increased probability of terminating runs in response to gradually decreasing concentration, the second an increased probability of terminating head casts in response to rapidly increasing concentration, and the third a biasing of run directions up concentration gradients through modulation of small head casts. We show that this model can be tuned to produce behavioural statistics comparable to those reported for the larva, and that this tuning results in similar chemotaxis performance to the larva. We demonstrate that each mechanism can enable odour approach but the combination of mechanisms is most effective, and investigate how these low-level control mechanisms relate to behavioural measures such as the preference indices used to investigate larval learning behaviour in group assays. PMID:26600460

  11. Sensitivity of Mytilus galloprovincialis larvae to ammonia

    SciTech Connect

    Gardiner, W.W.; Antrim, L.D.; Word, J.Q.

    1994-12-31

    Free ammonia is a constituent of some marine effluents and sediments. The authors evaluated the sensitivity of the larval stage of the marine bivalve, Mytilus galloprovincialis, to concentrations of ammonium sulfate, as well as to suspended-particulate-phase (SPP) preparations of marine sediments and petroleum-based marine effluents. Mytilus larvae are commonly used test organisms because of their sensitivity to toxicants and their use in evaluation of water-column impacts of dredged material disposal. Ammonia-only EC{sub 50} values were between 3 mg/L NH{sub 3} and 8 mg/L NH{sub 3}; LC{sub 50} values ranged from 66 mg/L NH{sub 3} to 100 mg/L NH{sub 3}. Abnormalities included exogastrulation and arrested development at early gastrulation. The EC{sub 50} values for ammonia in SPP and effluents were within similar ranges, which indicates that ammonia may contribute significantly to toxicity of these materials. Exposure of larvae during different developmental stages and time periods will also be discussed.

  12. Metamorphosis of cinctoblastula larvae (Homoscleromorpha, porifera).

    PubMed

    Ereskovsky, Alexander V; Tokina, Daria B; Bézac, Chantal; Boury-Esnault, Nicole

    2007-06-01

    The metamorphosis of the cinctoblastula of Homoscleromorpha is studied in five species belonging to three genera. The different steps of metamorphosis are similar in all species. The metamorphosis occurs by the invagination and involution of either the anterior epithelium or the posterior epithelium of the larva. During metamorphosis, morphogenetic polymorphism was observed, which has an individual character and does not depend on either external or species specific factors. In the rhagon, the development of the aquiferous system occurs only by epithelial morphogenesis and subsequent differentiation of cells. Mesohylar cells derive from flagellated cells after ingression. The formation of pinacoderm and choanoderm occurs by the differentiation of the larval flagellated epithelium. This is possibly due to the conservation of cell junctions in the external surface of the larval flagellated cells and of the basement membrane in their internal surface. The main difference in homoscleromorph metamorphosis compared with Demospongiae is the persistence of the flagellated epithelium throughout this process and even in the adult since exo- and endopinacoderm remain flagellated. The antero-posterior axis of the larva corresponds to the baso-apical axis of the adult in Homoscleromorpha.

  13. Cloning and expression patterns of the brine shrimp (Artemia sinica) glycogen phosphorylase (GPase) gene during development and in response to temperature stress.

    PubMed

    Zhao, Na; Hou, Ming; Wang, Ting; Chen, Yifei; Lv, Ying; Li, Zengrong; Zhang, Rui; Xin, Wenting; Zou, Xiangyang; Hou, Lin

    2014-01-01

    Glycogen serves as a metabolic reserve and is involved in macromolecular synthesis. Glycogen phosphorylase (GPase) is a key enzyme involved in intracellular glycogen catabolism, catalyzing the first step in glycogen degradation. In the diapause, GPase catalyzes glycogen into the closely related molecule, sorbitol. In this study, the full-length cDNA of the GPase gene (2,790 bp) was isolated from Artemia sinica for the first time by rapid amplification of cDNA ends technology. The GPase gene encoded a protein of 853 amino acids belonging to the Glycosyltransferase GTB type superfamily. The expression pattern and location of GPase were investigated at various stages during the embryonic development of A. sinica using real-time PCR and in situ hybridization. High GPase expression was detected at the 0 and 5 h stages. Subsequently, expression declined and was maintained at a low level during the stages from 10 to 40 h following by a small increase at day 3. Expression was downregulated at temperatures ranging from 25 to 20 °C and was subsequently upregulated in the range 15-5 °C. In situ hybridization assays showed wide distribution of the GPase gene during different developmental stages. From the results of this study, we conclude that the GPase gene expression is stress-related and might play an important role in Artemia development and metabolism. PMID:24323193

  14. Groundwater-quality data in the Monterey–Salinas shallow aquifer study unit, 2013: Results from the California GAMA Program

    USGS Publications Warehouse

    Goldrath, Dara A.; Kulongoski, Justin T.; Davis, Tracy A.

    2016-09-01

    Groundwater quality in the 3,016-square-mile Monterey–Salinas Shallow Aquifer study unit was investigated by the U.S. Geological Survey (USGS) from October 2012 to May 2013 as part of the California State Water Resources Control Board Groundwater Ambient Monitoring and Assessment (GAMA) Program’s Priority Basin Project. The GAMA Monterey–Salinas Shallow Aquifer study was designed to provide a spatially unbiased assessment of untreated-groundwater quality in the shallow-aquifer systems in parts of Monterey and San Luis Obispo Counties and to facilitate statistically consistent comparisons of untreated-groundwater quality throughout California. The shallow-aquifer system in the Monterey–Salinas Shallow Aquifer study unit was defined as those parts of the aquifer system shallower than the perforated depth intervals of public-supply wells, which generally corresponds to the part of the aquifer system used by domestic wells. Groundwater quality in the shallow aquifers can differ from the quality in the deeper water-bearing zones; shallow groundwater can be more vulnerable to surficial contamination.Samples were collected from 170 sites that were selected by using a spatially distributed, randomized grid-based method. The study unit was divided into 4 study areas, each study area was divided into grid cells, and 1 well was sampled in each of the 100 grid cells (grid wells). The grid wells were domestic wells or wells with screen depths similar to those in nearby domestic wells. A greater spatial density of data was achieved in 2 of the study areas by dividing grid cells in those study areas into subcells, and in 70 subcells, samples were collected from exterior faucets at sites where there were domestic wells or wells with screen depths similar to those in nearby domestic wells (shallow-well tap sites).Field water-quality indicators (dissolved oxygen, water temperature, pH, and specific conductance) were measured, and samples for analysis of inorganic

  15. CAH1 and CAH2 as key enzymes required for high bicarbonate tolerance of a novel microalga Dunaliella salina HTBS.

    PubMed

    Hou, Yuyong; Liu, Zhiyong; Zhao, Yue; Chen, Shulin; Zheng, Yubin; Chen, Fangjian

    2016-06-01

    Outdoor microalgal cultivation with high concentration bicarbonate has been considered as a strategy for reducing contamination and improving carbon supply efficiency. The mechanism responsible for algae's strong tolerance to high bicarbonate however, remains not clear. In this study, we isolated and characterized a strain and revealed its high bicarbonate tolerant mechanism by analyzing carbonic anhydrase (CA). The strain was identified as Dunaliella salina HTBS with broad temperature adaptability (7-30°C). The strain grew well under 30% CO2 or 70gL(-1) NaHCO3. In comparison, two periplasm CAs (CAH1 and CAH2) were detected with immunoblotting analysis in HTBS but not in a non-HCO3(-)-tolerant strain. The finding was also verified by an enzyme inhibition assay in which only HTBS showed significant inhibition by extracellular CA inhibitor. Thus, we inferred that the extracellular CAH1 and CAH2 played a multifunctional role in the toleration of high bicarbonate by HTBS.

  16. Changes in the Structure of the Microbial Community Associated with Nannochloropsis salina following Treatments with Antibiotics and Bioactive Compounds.

    PubMed

    Geng, Haifeng; Tran-Gyamfi, Mary B; Lane, Todd W; Sale, Kenneth L; Yu, Eizadora T

    2016-01-01

    Open microalgae cultures host a myriad of bacteria, creating a complex system of interacting species that influence algal growth and health. Many algal microbiota studies have been conducted to determine the relative importance of bacterial taxa to algal culture health and physiological states, but these studies have not characterized the interspecies relationships in the microbial communities. We subjected Nanochroloropsis salina cultures to multiple chemical treatments (antibiotics and quorum sensing compounds) and obtained dense time-series data on changes to the microbial community using 16S gene amplicon metagenomic sequencing (21,029,577 reads for 23 samples) to measure microbial taxa-taxa abundance correlations. Short-term treatment with antibiotics resulted in substantially larger shifts in the microbiota structure compared to changes observed following treatment with signaling compounds and glucose. We also calculated operational taxonomic unit (OTU) associations and generated OTU correlation networks to provide an overview of possible bacterial OTU interactions. This analysis identified five major cohesive modules of microbiota with similar co-abundance profiles across different chemical treatments. The Eigengenes of OTU modules were examined for correlation with different external treatment factors. This correlation-based analysis revealed that culture age (time) and treatment types have primary effects on forming network modules and shaping the community structure. Additional network analysis detected Alteromonadeles and Alphaproteobacteria as having the highest centrality, suggesting these species are "keystone" OTUs in the microbial community. Furthermore, we illustrated that the chemical tropodithietic acid, which is secreted by several species in the Alphaproteobacteria taxon, is able to drastically change the structure of the microbiota within 3 h. Taken together, these results provide valuable insights into the structure of the microbiota

  17. On-line stable isotope gas exchange reveals an inducible but leaky carbon concentrating mechanism in Nannochloropsis salina.

    PubMed

    Hanson, David T; Collins, Aaron M; Jones, Howland D T; Roesgen, John; Lopez-Nieves, Samuel; Timlin, Jerilyn A

    2014-09-01

    Carbon concentrating mechanisms (CCMs) are common among microalgae, but their regulation and even existence in some of the most promising biofuel production strains is poorly understood. This is partly because screening for new strains does not commonly include assessment of CCM function or regulation despite its fundamental role in primary carbon metabolism. In addition, the inducible nature of many microalgal CCMs means that environmental conditions should be considered when assessing CCM function and its potential impact on biofuels. In this study, we address the effect of environmental conditions by combining novel, high frequency, on-line (13)CO2 gas exchange screen with microscope-based lipid characterization to assess CCM function in Nannochloropsis salina and its interaction with lipid production. Regulation of CCM function was explored by changing the concentration of CO2 provided to continuous cultures in airlift bioreactors where cell density was kept constant across conditions by controlling the rate of media supply. Our isotopic gas exchange results were consistent with N. salina having an inducible "pump-leak" style CCM similar to that of Nannochloropsis gaditana. Though cells grew faster at high CO2 and had higher rates of net CO2 uptake, we did not observe significant differences in lipid content between conditions. Since the rate of CO2 supply was much higher for the high CO2 conditions, we calculated that growing cells bubbled with low CO2 is about 40 % more efficient for carbon capture than bubbling with high CO2. We attribute this higher efficiency to the activity of a CCM under low CO2 conditions. PMID:24844569

  18. The influence of photoperiod and light intensity on the growth and photosynthesis of Dunaliella salina (chlorophyta) CCAP 19/30.

    PubMed

    Xu, Yanan; Ibrahim, Iskander M; Harvey, Patricia J

    2016-09-01

    The green microalga Dunaliella salina survives in a wide range of salinities via mechanisms involving glycerol synthesis and degradation and is exploited for large amounts of nutraceutical carotenoids produced under stressed conditions. In this study, D. salina CCAP 19/30 was cultured in varying photoperiods and light intensities to study the relationship of light with different growth measurement parameters, with cellular contents of glycerol, starch and carotenoids, and with photosynthesis and respiration. Results show CCAP 19/30 regulated cell volume when growing under light/dark cycles: cell volume increased in the light and decreased in the dark, and these changes corresponded to changes in cellular glycerol content. The decrease in cell volume in the dark was independent of cell division and biological clock and was regulated by the photoperiod of the light/dark cycle. When the light intensity was increased to above 1000 μmol photons m(-2) s(-1), cells displayed evidence of photodamage. However, these cells also maintained the maximum level of photosynthesis efficiency and respiration possible, and the growth rate increased as light intensity increased. Significantly, the intracellular glycerol content also increased, >2-fold compared to the content in light intensity of 500 μmol photons m(-2) s(-1), but there was no commensurate increase in the pool size of carotenoids. These data suggest that in CCAP 19/30 glycerol stabilized the photosynthetic apparatus for maximum performance in high light intensities, a role normally attributed to carotenoids.

  19. Influence of PbS nanoparticle polymer coating on their aggregation behavior and toxicity to the green algae Dunaliella salina.

    PubMed

    Zamani, Hajar; Moradshahi, Ali; Jahromi, Hamed Dehdashti; Sheikhi, Mohammad Hosein

    2014-09-01

    The potential hazards of nanoparticles (NPs) to the environment and to living organisms need to be considered for a safe development of nanotechnology. In the present study, the potential toxic effects of uncoated and gum Arabic-coated lead sulfide nanoparticles (GA-coated PbS NPs) on the growth, lipid peroxidation, reducing capacity and total carotenoid content of the hypersaline unicellular green algae Dunaliella salina were investigated. Coatings of PbS NPs with GA, as confirmed by Fourier transform infrared spectroscopy, reduced the toxicity of PbS NPs. Uncoated PbS NP toxicity to D. salina was attributed to higher algal cell-NP agglomerate formation, higher lipid peroxidation, lower content of total reducing substances and lower total carotenoid content. Low levels of Pb(2+) in the growth culture media indicate that PbS NP dissolution does not occur in the culture. Also, the addition of 100 μM Pb(2+) to the culture media had no significant (P>0.05) effect on algal growth. The shading of light (shading effect) by PbS NPs, when simulated using activated charcoal, did not contribute to the overall toxic effect of PbS NPs which was evident by insignificant (P>0.05) reduction in the growth and antioxidant capacity of the algae. When PbS NP aggregation in culture media (without algal cells) was followed for 60 min, uncoated form aggregated rapidly reaching aggregate sizes with hydrodynamic diameter of over 2500 nm within 60 min. Effective particle-particle interaction was reduced in the GA-coated NPs. Aggregates of about 440 nm hydrodynamic diameter were formed within 35 min. Afterwards the aggregate size remained constant. It is concluded that PbS NPs have a negative effect on aquatic algae and their transformation by GA capping affects NPs aggregation properties and toxicity.

  20. Changes in the Structure of the Microbial Community Associated with Nannochloropsis salina following Treatments with Antibiotics and Bioactive Compounds

    DOE PAGESBeta

    Geng, Haifeng; Tran-Gyamfi, Mary B.; Lane, Todd W.; Sale, Kenneth L.; Yu, Eizadora T.

    2016-07-26

    Open microalgae cultures host a myriad of bacteria, creating a complex system of interacting species that influence algal growth and health. Many algal microbiota studies have been conducted to determine the relative importance of bacterial taxa to algal culture health and physiological states, but these studies have not characterized the interspecies relationships in the microbial communities. Here we subjected Nanochroloropsis salina cultures to multiple chemical treatments (antibiotics and quorum sensing compounds) and obtained dense time-series data on changes to the microbial community using 16S gene amplicon metagenomic sequencing (21,029,577 reads for 23 samples) to measure microbial taxa-taxa abundance correlations. Short-termmore » treatment with antibiotics resulted in substantially larger shifts in the microbiota structure compared to changes observed following treatment with signaling compounds and glucose. We also calculated operational taxonomic unit (OTU) associations and generated OTU correlation networks to provide an overview of possible bacterial OTU interactions. This analysis identified five major cohesive modules of microbiota with similar co-abundance profiles across different chemical treatments. The Eigengenes of OTU modules were examined for correlation with different external treatment factors. This correlation-based analysis revealed that culture age (time) and treatment types have primary effects on forming network modules and shaping the community structure. Additional network analysis detected Alteromonadeles and Alphaproteobacteria as having the highest centrality, suggesting these species are “keystone” OTUs in the microbial community. Furthermore, we illustrated that the chemical tropodithietic acid, which is secreted by several species in the Alphaproteobacteria taxon, is able to drastically change the structure of the microbiota within 3 h. Lastly, taken together, these results provide valuable insights into the structure

  1. Changes in the Structure of the Microbial Community Associated with Nannochloropsis salina following Treatments with Antibiotics and Bioactive Compounds

    PubMed Central

    Geng, Haifeng; Tran-Gyamfi, Mary B.; Lane, Todd W.; Sale, Kenneth L.; Yu, Eizadora T.

    2016-01-01

    Open microalgae cultures host a myriad of bacteria, creating a complex system of interacting species that influence algal growth and health. Many algal microbiota studies have been conducted to determine the relative importance of bacterial taxa to algal culture health and physiological states, but these studies have not characterized the interspecies relationships in the microbial communities. We subjected Nanochroloropsis salina cultures to multiple chemical treatments (antibiotics and quorum sensing compounds) and obtained dense time-series data on changes to the microbial community using 16S gene amplicon metagenomic sequencing (21,029,577 reads for 23 samples) to measure microbial taxa-taxa abundance correlations. Short-term treatment with antibiotics resulted in substantially larger shifts in the microbiota structure compared to changes observed following treatment with signaling compounds and glucose. We also calculated operational taxonomic unit (OTU) associations and generated OTU correlation networks to provide an overview of possible bacterial OTU interactions. This analysis identified five major cohesive modules of microbiota with similar co-abundance profiles across different chemical treatments. The Eigengenes of OTU modules were examined for correlation with different external treatment factors. This correlation-based analysis revealed that culture age (time) and treatment types have primary effects on forming network modules and shaping the community structure. Additional network analysis detected Alteromonadeles and Alphaproteobacteria as having the highest centrality, suggesting these species are “keystone” OTUs in the microbial community. Furthermore, we illustrated that the chemical tropodithietic acid, which is secreted by several species in the Alphaproteobacteria taxon, is able to drastically change the structure of the microbiota within 3 h. Taken together, these results provide valuable insights into the structure of the microbiota

  2. Influence of PbS nanoparticle polymer coating on their aggregation behavior and toxicity to the green algae Dunaliella salina.

    PubMed

    Zamani, Hajar; Moradshahi, Ali; Jahromi, Hamed Dehdashti; Sheikhi, Mohammad Hosein

    2014-09-01

    The potential hazards of nanoparticles (NPs) to the environment and to living organisms need to be considered for a safe development of nanotechnology. In the present study, the potential toxic effects of uncoated and gum Arabic-coated lead sulfide nanoparticles (GA-coated PbS NPs) on the growth, lipid peroxidation, reducing capacity and total carotenoid content of the hypersaline unicellular green algae Dunaliella salina were investigated. Coatings of PbS NPs with GA, as confirmed by Fourier transform infrared spectroscopy, reduced the toxicity of PbS NPs. Uncoated PbS NP toxicity to D. salina was attributed to higher algal cell-NP agglomerate formation, higher lipid peroxidation, lower content of total reducing substances and lower total carotenoid content. Low levels of Pb(2+) in the growth culture media indicate that PbS NP dissolution does not occur in the culture. Also, the addition of 100 μM Pb(2+) to the culture media had no significant (P>0.05) effect on algal growth. The shading of light (shading effect) by PbS NPs, when simulated using activated charcoal, did not contribute to the overall toxic effect of PbS NPs which was evident by insignificant (P>0.05) reduction in the growth and antioxidant capacity of the algae. When PbS NP aggregation in culture media (without algal cells) was followed for 60 min, uncoated form aggregated rapidly reaching aggregate sizes with hydrodynamic diameter of over 2500 nm within 60 min. Effective particle-particle interaction was reduced in the GA-coated NPs. Aggregates of about 440 nm hydrodynamic diameter were formed within 35 min. Afterwards the aggregate size remained constant. It is concluded that PbS NPs have a negative effect on aquatic algae and their transformation by GA capping affects NPs aggregation properties and toxicity. PMID:24907922

  3. The influence of photoperiod and light intensity on the growth and photosynthesis of Dunaliella salina (chlorophyta) CCAP 19/30.

    PubMed

    Xu, Yanan; Ibrahim, Iskander M; Harvey, Patricia J

    2016-09-01

    The green microalga Dunaliella salina survives in a wide range of salinities via mechanisms involving glycerol synthesis and degradation and is exploited for large amounts of nutraceutical carotenoids produced under stressed conditions. In this study, D. salina CCAP 19/30 was cultured in varying photoperiods and light intensities to study the relationship of light with different growth measurement parameters, with cellular contents of glycerol, starch and carotenoids, and with photosynthesis and respiration. Results show CCAP 19/30 regulated cell volume when growing under light/dark cycles: cell volume increased in the light and decreased in the dark, and these changes corresponded to changes in cellular glycerol content. The decrease in cell volume in the dark was independent of cell division and biological clock and was regulated by the photoperiod of the light/dark cycle. When the light intensity was increased to above 1000 μmol photons m(-2) s(-1), cells displayed evidence of photodamage. However, these cells also maintained the maximum level of photosynthesis efficiency and respiration possible, and the growth rate increased as light intensity increased. Significantly, the intracellular glycerol content also increased, >2-fold compared to the content in light intensity of 500 μmol photons m(-2) s(-1), but there was no commensurate increase in the pool size of carotenoids. These data suggest that in CCAP 19/30 glycerol stabilized the photosynthetic apparatus for maximum performance in high light intensities, a role normally attributed to carotenoids. PMID:27231875

  4. Loeffler's Syndrome Following Cutaneous Larva Migrans: An Uncommon Sequel

    PubMed Central

    Podder, Indrashis; Chandra, Somodyuti; Gharami, Ramesh Chandra

    2016-01-01

    Cutaneous larva migrans (CLM) is characterized by the formation of distinctive, tortuous, and serpentine skin lesions occurring as a result of epidermal burrowing by certain helminthic larvae. Although this condition is usually uneventful, rarely it may result in patchy pulmonary infiltration with peripheral eosinophilia, also called Loeffler's syndrome. This association is fairly uncommon and is thus being reported. PMID:27057020

  5. Selenium impacts on razorback sucker, Colorado: Colorado River: III. Larvae

    USGS Publications Warehouse

    Hamilton, S.J.; Holley, K.M.; Buhl, K.J.; Bullard, F.A.

    2005-01-01

    Razorback sucker (Xyrauchen texanus) larvae from adults exposed to selenium at three sites near Grand Junction, Colorado, for 9 months were used in a 30-day waterborne and dietary selenium study. Selenium concentrations in water averaged <1.6 ??g/L from 24-Road, 0.9 ??g/L from Horsethief, 5.5 ??g/L from Adobe Creek, and 10.7 ??g/L from the North Pond. Selenium in dietary items averaged 2.7 ??g/g in brine shrimp, 5.6 ??g/g in zooplankton from Horsethief east wetland, 20 ??g/g in zooplankton from Adobe Creek, and 39 ??g/g in zooplankton from North Pond. The lowest survival occurred in larvae fed zooplankton rather than brine shrimp. Survival of larvae at Adobe Creek and North Pond was lower in site water than in reference water. Survival of brood stock larvae was higher than Horsethief larvae even though they received the same water and dietary treatments. Arsenic concentrations in brine shrimp may have resulted in an antagonistic interaction with selenium and reduced adverse effects in larvae. Deformities in larvae from North Pond were similar to those reported for selenium-induced teratogenic deformities in other fish species. Selenium concentrations of ???4.6 ??g/g in food resulted in rapid mortality of larvae from Horsethief, Adobe Creek, and North Pond, and suggested that selenium toxicity in the Colorado River could limit recovery of this endangered fish.

  6. Selenium impacts on razorback sucker, Colorado: Colorado River III. Larvae.

    PubMed

    Hamilton, Steven J; Holley, Kathy M; Buhl, Kevin J; Bullard, Fern A

    2005-06-01

    Razorback sucker (Xyrauchen texanus) larvae from adults exposed to selenium at three sites near Grand Junction, Colorado, for 9 months were used in a 30-day waterborne and dietary selenium study. Selenium concentrations in water averaged <1.6 microg/L from 24-Road, 0.9 microg/L from Horsethief, 5.5 microg/L from Adobe Creek, and 10.7 microg/L from the North Pond. Selenium in dietary items averaged 2.7 microg/g in brine shrimp, 5.6 microg/g in zooplankton from Horsethief east wetland, 20 microg/g in zooplankton from Adobe Creek, and 39 microg/g in zooplankton from North Pond. The lowest survival occurred in larvae fed zooplankton rather than brine shrimp. Survival of larvae at Adobe Creek and North Pond was lower in site water than in reference water. Survival of brood stock larvae was higher than Horsethief larvae even though they received the same water and dietary treatments. Arsenic concentrations in brine shrimp may have resulted in an antagonistic interaction with selenium and reduced adverse effects in larvae. Deformities in larvae from North Pond were similar to those reported for selenium-induced teratogenic deformities in other fish species. Selenium concentrations of 4.6 microg/g in food resulted in rapid mortality of larvae from Horsethief, Adobe Creek, and North Pond, and suggested that selenium toxicity in the Colorado River could limit recovery of this endangered fish.

  7. Active downward propulsion by oyster larvae in turbulence.

    PubMed

    Fuchs, Heidi L; Hunter, Elias J; Schmitt, Erika L; Guazzo, Regina A

    2013-04-15

    Oyster larvae (Crassostrea virginica) could enhance their settlement success by moving toward the seafloor in the strong turbulence associated with coastal habitats. We characterized the behavior of individual oyster larvae in grid-generated turbulence by measuring larval velocities and flow velocities simultaneously using infrared particle image velocimetry. We estimated larval behavioral velocities and propulsive forces as functions of the kinetic energy dissipation rate ε, strain rate γ, vorticity ξ and acceleration α. In calm water most larvae had near-zero vertical velocities despite propelling themselves upward (swimming). In stronger turbulence all larvae used more propulsive force, but relative to the larval axis, larvae propelled themselves downward (diving) instead of upward more frequently and more forcefully. Vertical velocity magnitudes of both swimmers and divers increased with turbulence, but the swimming velocity leveled off as larvae were rotated away from their stable, velum-up orientation in strong turbulence. Diving speeds rose steadily with turbulence intensity to several times the terminal fall velocity in still water. Rapid dives may require a switch from ciliary swimming to another propulsive mode such as flapping the velum, which would become energetically efficient at the intermediate Reynolds numbers attained by larvae in strong turbulence. We expected larvae to respond to spatial or temporal velocity gradients, but although the diving frequency changed abruptly at a threshold acceleration, the variation in propulsive force and behavioral velocity was best explained by the dissipation rate. Downward propulsion could enhance oyster larval settlement by raising the probability of larval contact with oyster reef patches.

  8. Early detection of non-native fishes using fish larvae

    EPA Science Inventory

    Our objective was to evaluate the use of fish larvae for early detection of non-native fishes, comparing traditional and molecular taxonomy approaches to investigate potential efficiencies. Fish larvae present an interesting opportunity for non-native fish early detection. First,...

  9. Selenium impacts on razorback sucker, Colorado: Colorado River III. Larvae.

    PubMed

    Hamilton, Steven J; Holley, Kathy M; Buhl, Kevin J; Bullard, Fern A

    2005-06-01

    Razorback sucker (Xyrauchen texanus) larvae from adults exposed to selenium at three sites near Grand Junction, Colorado, for 9 months were used in a 30-day waterborne and dietary selenium study. Selenium concentrations in water averaged <1.6 microg/L from 24-Road, 0.9 microg/L from Horsethief, 5.5 microg/L from Adobe Creek, and 10.7 microg/L from the North Pond. Selenium in dietary items averaged 2.7 microg/g in brine shrimp, 5.6 microg/g in zooplankton from Horsethief east wetland, 20 microg/g in zooplankton from Adobe Creek, and 39 microg/g in zooplankton from North Pond. The lowest survival occurred in larvae fed zooplankton rather than brine shrimp. Survival of larvae at Adobe Creek and North Pond was lower in site water than in reference water. Survival of brood stock larvae was higher than Horsethief larvae even though they received the same water and dietary treatments. Arsenic concentrations in brine shrimp may have resulted in an antagonistic interaction with selenium and reduced adverse effects in larvae. Deformities in larvae from North Pond were similar to those reported for selenium-induced teratogenic deformities in other fish species. Selenium concentrations of 4.6 microg/g in food resulted in rapid mortality of larvae from Horsethief, Adobe Creek, and North Pond, and suggested that selenium toxicity in the Colorado River could limit recovery of this endangered fish. PMID:15883090

  10. Larvae of Amphipsyche species (Trichoptera: Hydropsychidae) from Thailand.

    PubMed

    Peumwarunyoo, Pronthip; Prommi, Taeng-on

    2013-01-01

    Morphological characters and scanning electron microscope images of the larvae of Amphipsyche meridiana and A. gratiosa are given. Pupal identifications are based on genitalic features in common with described adults, and larvae were associated with the pupae based on residual larval sclerites captured in the pupal case. Herein, the final larval instar is described, diagnosed, and photographed for each species.

  11. The Larva of Diplectrona magna Mosely, 1930 (Trichoptera: Hydropsychidae)

    PubMed Central

    WARINGER, JOHANN; GRAF, WOLFRAM

    2016-01-01

    The larva of Diplectrona magna Mosely, 1930 is described and compared with the other European Diplectrona larvae described so far. Information for the identification of three species (D. atra, D. felix and D. magna) is given and some zoogeographical and ecological notes are presented. PMID:26973367

  12. Trail marking by larvae of the eastern tent caterpillar.

    PubMed

    Fitzgerald, T D

    1976-11-26

    Eastern tent caterpillars that are successful foragers deposit trails as they return to the tent that are more attractive than the exploratory trails of the unfed larvae. The trails of these fed returning larvae attract unfed tentmates to food finds anre chemical factors account for the attractiveness of these trails.

  13. The effects of dissolved gas supersaturation on white sturgeon larvae

    USGS Publications Warehouse

    Counihan, T.D.; Miller, A.I.; Mesa, M.G.; Parsley, M.J.

    2000-01-01

    Spill at dams has caused supersaturation of atmospheric gas in waters of the Columbia and Snake rivers and raised concerns about the effects of dissolved gas supersaturation (DGS) on white sturgeons Acipenser transmontanus. The timing and location of white sturgeon spawning and the dispersal of white sturgeon larvae from incubation areas makes the larval stage potentially vulnerable to the effects of DGS. To assess the effects of DGS on white sturgeon larvae, we exposed larvae to mean total dissolved gas (TDG) levels of 118% and 131% saturation in laboratory bioassay tests. Gas bubble trauma (GBT) was manifested as a gas bubble in the buccal cavity, nares, or both and it first occurred at developmental stages characterized by the formation of the mouth and gills. Exposure times of 15 min were sufficient to elicit these signs in larvae in various stages of development. No mortality was observed in larvae exposed to 118% TDG for 10 d, but 50% mortality occurred after a 13-d exposure to 131% TDG. The signs of GBT we observed resulted in positive buoyancy and alterations in behavior that may affect the dispersal and predation vulnerability of white sturgeon larvae. The exact depth distribution of dispersing white sturgeon larvae in the Columbia River currently is unknown. Thus, our results may represent a worst-case scenario if white sturgeon larvae are dispersed at depths with insufficient hydrostatic pressure to compensate for high TDG levels.

  14. Discovery of mammalian hosts to Gnathostoma nipponicum larvae and prevalence of the larvae in rodents and insectivores.

    PubMed

    Oyamada, T; Kobayashi, H; Kindou, T; Kudo, N; Yoshikawa, H; Yoshikawa, T

    1996-09-01

    From September 1993 to November 1995, to clarify the natural infection of Gnathostoma nipponicum (G.n.) larvae in small wild mammals, a total of 313 animals consisted of three species of rodents and two species of insectivores, collected from an endemic area of this nematode in Aomori Prefecture, were investigated. Two species, Rattus norvegicus (R.n.) and Chimarrogale himalayica (C.h.) were infected with G.n. larvae, and the infection rate was extremely high with 27.2% and 72.7% in the former and latter. The infected animals harbored the larvae of 2-10 (mean: 6.0) in R.N. and 2-40 (10.6) in C.h., and a total of 273 larvae was recovered. The all larvae (18) from R.n. and the vast majority of the larvae (216/255: 82.4%) from C.h. were recovered from the musculature, and many encapsulated larvae were found in these portions of C.h. Taxonomically, all the larvae were identified as the advance third-stage larvae (AdL3) of G.n. The body length was 1,056-2,110 microns, and was larger than those of the naturally-infected AdL3 reported from cold-blooded animals. No morphological alterations or death of the larva was observed. From these results, it would seem that R.n. and C.h. are highly susceptible to G.n. larvae, and has very suitable characteristics as the hosts. Furthermore, a hypothesis is advanced that these mammals serves as the plausible paratenic hosts in the life cycle of G.n. This report is the first record of R.n. (Rodentia) and C.h. (Insectivora) naturally-infected with AdL3 of G.n.

  15. [Tungiasis and cutaneous larva migrans: unpleasant travel souvenirs].

    PubMed

    Feldmeier, Hermann

    2009-12-01

    Tungiasis (sand flea disease) and cutaneous larva migrans (creeping eruption) are parasitic skin diseases in which the infectious agents only temporarily invade human skin. The parasites die in situ and eventually are eliminated by tissue repair mechanisms. Both diseases are zoonoses. Humans only accidentally become a host for animal hookworm larvae (resulting in cutaneous larva migrans), but get infected with Tunga penetrans as frequent as domestic animals. In travelers to tropical and subtropical regions tungiasis and cutaneous larva migrans are the most common imported skin diseases. The diagnosis is made clinically. In tungiasis the clinical manifestations depend on the stage of the disease. Intense local inflammation and bacterial superinfection are common. Cutaneous larva migrans is treated orally with ivermectin or albendazole. A repellent based on coconut oil effectively prevents penetration of sand fleas.

  16. [Tungiasis and cutaneous larva migrans: unpleasant travel souvenirs].

    PubMed

    Feldmeier, Hermann

    2009-12-01

    Tungiasis (sand flea disease) and cutaneous larva migrans (creeping eruption) are parasitic skin diseases in which the infectious agents only temporarily invade human skin. The parasites die in situ and eventually are eliminated by tissue repair mechanisms. Both diseases are zoonoses. Humans only accidentally become a host for animal hookworm larvae (resulting in cutaneous larva migrans), but get infected with Tunga penetrans as frequent as domestic animals. In travelers to tropical and subtropical regions tungiasis and cutaneous larva migrans are t