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Efecto de metales pesados en el crecimiento de la microalga tropical Tetraselmis chuii (Prasinophyceae)
Cordero,Jiudith; Guevara,Miguel; Morales,Ever; Lodeiros,César;
Revista de Biología Tropical , 2005,
Abstract: efect of heavy metals on the growth of the tropical microalga tetrasermis chuii (prasinophyceae). we determined the toxic effect of four metals, cadmium (cd), copper (cu), mercury (hg) and lead (pb), on the tropical microalga tetraselmis chuii (butcher, 1959). we exposed 50 ml of cultivated microalgae (f/2 guillard) in the exponential growth phase, with three replicates, to concentrations of 0 (control), 0.1, 1.0, 5.0, 10.0 and 20.0 mg· l-1 with each metal for 96 hr. we evaluated the lethal effect daily, through the cellular count. in the control treatment (not exposed to any metal) we observed an increase in cellular density. in all treatments exposed to metals, we observed a decrease in cellular density, which accelerated in 48 h, after which it became less pronounced. there were exceptions with low concentrations of cd and cu at 24 h, as there was no significant decrease, probably due to their use as micronutrients at these low concentrations. the metal that caused the most lethal effect was pb, which killed 50% of the microalgal population at a concentration of 0.40 mg· l-1. this concentration was 3 times lower than that of mercury and 13 times lower than those of cadmium and copper. the microalga tetraselmis chuii is recommended as a model species to estimate the toxic effects of xenobiotics on tropical seawater environments. rev. biol. trop. 53(3-4): 325-330. epub 2005 oct 3.
Efecto de metales pesados en el crecimiento de la microalga tropical Tetraselmis chuii (Prasinophyceae)  [cached]
Jiudith Cordero,Miguel Guevara,Ever Morales,César Lodeiros
Revista de Biología Tropical , 2005,
Abstract: El presente trabajo determina el efecto tóxico de los metales cadmio (Cd), cobre (Cu), mercurio (Hg) y plomo (Pb) en la microalga tropical Tetraselmis chuii (Butcher, 1959). Se expuso, por triplicado, 50 ml de cultivo (f/2 Guillard) de la microalga en fase de crecimiento logarítmica ante las concentraciones de 0 (control); 0.1; 1.0; 5.0; 10.0 y 20.0 mg· l-1 durante 96 hr. La evaluación del efecto letal se realizó diariamente, mediante recuento celular con una cámara de Neubauer. En el tratamiento control, sin exposición al metal, se observó un incremento de la densidad celular, en contraste con un decrecimiento en los tratamientos con exposición a los metales, los cuales fueron acelerados hasta las 48 hr, a partir de cuando el decrecimiento se hizo menos pronunciado. Una excepción se produjo con el Cd y el Cu a las 24 h, donde no se determinó decrecimiento significativo, probablemente debido a su capacidad de actuar como micronutriente a bajas concentraciones. El metal que produjo mayor efecto fue el Pb, produciendo una letalidad al 50% de la población microalgal a 0.40 mg· l-1, la cual fue casi tres veces menor que la establecida para el Hg y más de 13 veces menor que la del Cd y Cu. Se recomienda la microalga Tetraselmis chuii como especie modelo para la utilización en pruebas en función estimar efectos tóxicos por xenobióticos en el ambiente acuático marino tropical. Efect of heavy metals on the growth of the tropical microalga Tetrasermis chuii (Prasinophyceae). We determined the toxic effect of four metals, cadmium (Cd), copper (Cu), mercury (Hg) and lead (Pb), on the tropical microalga Tetraselmis Chuii (Butcher, 1959). We exposed 50 ml of cultivated microalgae (f/2 Guillard) in the exponential growth phase, with three replicates, to concentrations of 0 (control), 0.1, 1.0, 5.0, 10.0 and 20.0 mg· l-1 with each metal for 96 hr. We evaluated the lethal effect daily, through the cellular count. In the control treatment (not exposed to any metal) we observed an increase in cellular density. In all treatments exposed to metals, we observed a decrease in cellular density, which accelerated in 48 h, after which it became less pronounced. There were exceptions with low concentrations of Cd and Cu at 24 h, as there was no significant decrease, probably due to their use as micronutrients at these low concentrations. The metal that caused the most lethal effect was Pb, which killed 50% of the microalgal population at a concentration of 0.40 mg· l-1. This concentration was 3 times lower than that of mercury and 13 times lower than those of cadmium and copper.
Biochemical Effects of Different Salinities and Luminance on Green Microalgae Tetraselmis chuii
F. Ghezelbash,T. Farboodnia,R. Heidari,N. Agh
Research Journal of Biological Sciences , 2012,
Abstract: In this study the effects of (20, 30, 40, 50 ppt) salinities and (2500, 4500, 6500 Lux) luminances on the changes of chlorophylls, carbohydrates, proline and proteins of unicellular microalga Tetraselmis chuii have been studied in the controlled conditions. The results indicated that the amounts of all of these parameters have been influenced by the salinity and light intensities. The amount of proteins have not been changed significantly in all cases. Carbohydrats and proline contents as osmoregulators have been increased in stress conditions. But the amount of chlorophylls have been reduced while carotenoids contents have been increased. So we conclude that as like as higher plants high and low (in halophytes) salinities and light intensities cause some biochemical changes in unicellular green microalgea. In many cases adaptation mechanisms to stress conditions are the same in them, such as increased accumulation of proline and carbohydrates and some changes in pigments and protein contents of the cells of organism. Due to these results and other similarities, perhaps higher plants have been originated from these green unicellular algae.
Biochemical Effects of Different Salinities and Luminance on Green Microalgae Tetraselmis chuii
F. Ghezelbash,T. Farboodnia,R. Heidari,N. Agh
Research Journal of Biological Sciences , 2008,
Abstract: In this study the effects of (20, 30, 40, 50 ppt) salinities and (2500, 4500, 6500 Lux) luminances on the changes of chlorophylls, carbohydrates, proline and proteins of unicellular microalga Tetraselmis chuii have been studied in the controlled conditions. The results indicated that the amounts of all of these parameters have been influenced by the salinity and light intensities. The amount of proteins have not been changed significantly in all cases. Carbohydrats and proline contents as osmoregulators have been increased in stress conditions. But the amount of chlorophylls have been reduced while carotenoids contents have been increased. So we conclude that as like as higher plants high and low (in halophytes) salinities and light intensities cause some biochemical changes in unicellular green microalgea. In many cases adaptation mechanisms to stress conditions are the same in them, such as increased accumulation of proline and carbohydrates and some changes in pigments and protein contents of the cells of organism. Due to these results and other similarities, perhaps higher plants have been originated from these green unicellular algae.
Growth, Proximate Composition and Pigment Production of Tetraselmis chuii Cultured with Aquaculture Wastewater Growth, Proximate Composition and Pigment Production of Tetraselmis chuii Cultured with Aquaculture Wastewater  [PDF]
KHATOON Helena,HARIS Haris,RAHMAN Norazira Abdu,ZAKARIA Mimi Nadzirah,BEGUM Hasina,MIAN Sohel
- , 2018,
Abstract: Microalgae are cultured commercially as healthy food, cosmetic products, food preservatives, and a source of valuable compounds. However, the high cost of commercial culture medium is one of the challenges to microalgal production. Therefore, it is essential to find an alternative cost-effective culture medium. Aquaculture wastewater is considered as a highly potential candidate due to its high nutrient content and large quantity generated from the rapid growth of aquaculture sector. In this study, Tetraselmis chuii cultured in different media with or without wastewater was evaluated for its growth, proximate composition and carotenoid production. The results showed that significantly(P < 0.05) higher growth(4.3 × 105 cells mL~(-1)) and protein(56.4% dry weight), lipid(44% dry weight) and carbohydrate(20% of dry weight) contents were found in T. chuii when they were cultured in the combination of both wastewater and Conway(wastewater + Conway) medium. However, carotenoid production of T. chuii was significantly increased(P < 0.05) when it was cultured in wastewater only, followed by Conway + wastewater and Conway medium only. Therefore, the incorporation of wastewater with commercial medium Convey is recommended for a cost-effective microalgae culture, as well as for the enhancement of growth and nutritional content of microalgae
Effects of Different Salinities and Luminance on Growth Rate of the Green Microalgae Tetraselmis chuii
F. Ghezelbash,T. Farboodnia,R. Heidari,N. Agh
Research Journal of Biological Sciences , 2012,
Abstract: In this study, the effects of (20, 30, 40 and 50 ppt) salinities and (500, 2500, 4500 and 6500 lux) luminance on the changes of the amount of biomass and the growth rate of the microalgae Tetraselmis chuii. have been studied in the controlled conditions. The growth rate, has been expressed as the number of cells mL 1. The results have indicated that the growth rate of this microalgae has varied and influenced by the salinity and light intensities. In this research, growth rate has been decreased by the salinity and light intensity and the highest biomass was observed in 40 ppt salinity 4500 lux and the lowest was in 20 ppt salinity 500 lux. We conclude that as like as higher plants high and low (in halophytes) salinities and light intensities cause some changes in different phases of growth rate and other biochemical aspects in unicellular green microalgea. So to maintain such these researches help us to find out the best condition that suits for the growth and culture of microalgea specially those that more important economically and are used by other organisms in food chain.
Urban secondary sewage: an alternative medium for the culture of Tetraselmis chuii (Prasinophyceae) and Dunaliella viridis (Chlorophyceae)
Costa, Rauquírio André Albuquerque Marinho da;Koening, Maria Luise;Macedo, Sílvio José de;
Brazilian Archives of Biology and Technology , 2004, DOI: 10.1590/S1516-89132004000300016
Abstract: the effect of different concentrations (10, 20, 30 and 40%) of urban secondary sewage on the growth of tetraselmis chuii (prasinophyceae) and dunaliella viridis (chlorophyceae) was examined to verify the possibility of its use as an alternative culture medium for these species. stocks and 700ml duplicate batch cultures were maintained under controlled laboratory conditions. 30% and 40% additions were the most efficient for the growth of both species. statistical analysis of the adjusted growth (cell.ml-1) and biomass (μg chlorophyll-a.ml-1) curves performed using the chi-square test (p<0.05) demonstrated significant differences between the nutritive medium f/2 and the 40% addition used for these two species. the results suggested that some of the concentrations tested here yielded satisfactory cell densities and growth rates when compared with other culture media (macroalgae, bovine and chicken manure extracts). thus it could be used by semi intensive aquaculture systems.
Effects of Different Salinities and Luminance on Growth Rate of the Green Microalgae Tetraselmis chuii
F. Ghezelbash,T. Farboodnia,R. Heidari,N. Agh
Research Journal of Biological Sciences , 2008,
Abstract: In this study, the effects of (20, 30, 40 and 50 ppt) salinities and (500, 2500, 4500 and 6500 lux) luminance on the changes of the amount of biomass and the growth rate of the microalgae Tetraselmis chuii. have been studied in the controlled conditions. The growth rate, has been expressed as the number of cells mL -1. The results have indicated that the growth rate of this microalgae has varied and influenced by the salinity and light intensities. In this research, growth rate has been decreased by the salinity and light intensity and the highest biomass was observed in 40 ppt salinity x 4500 lux and the lowest was in 20 ppt salinity x 500 lux. We conclude that as like as higher plants high and low (in halophytes) salinities and light intensities cause some changes in different phases of growth rate and other biochemical aspects in unicellular green microalgea. So to maintain such these researches help us to find out the best condition that suits for the growth and culture of microalgea specially those that more important economically and are used by other organisms in food chain.
The effect of inoculation time and inoculum concentration on the productive response of Tetraselmis chuii (Butcher, 1958) mass cultured in F/2 and 2-F media
López-Elías José A.,Esquer-Miranda Edgard,Martínez-Porchas Marcel,Garza-Aguirre María C.
Archives of Biological Sciences , 2011, DOI: 10.2298/abs1103557l
Abstract: Diverse protocols have been used in the shrimp industry to produce microalgae. In this work, we evaluated the effect of inoculation time (0600 and 1200) and initial microalgae density (0.4 and 0.8 x105cells mL-1) in static outdoor cultures of Tetraselmis chuii, using F/2 and 2-F media. A significant effect on cell density (> 6.7 x 105 cells mL-1) was found after treatments with a high initial density and in the F/2 medium. The higher productive responses were observed in treatments inoculated at 0600. The better productive response was found in treatments inoculated at 0600 with 0.8 x 105 cells mL-1 in the F/2 medium.
Efeito do meio Erd Schreiber no cultivo das microalgas Dunaliella salina, Tetraselmis chuii e Isochrysis galbana = Erd Schreiber medium effect in culture of microalgae Dunaliella salina, Tetraselmis chuii and Isochrysis galbana  [cached]
Nyamien Yahaut Sebastien,Vera Lucia Mota Klein
Acta Scientiarum : Biological Sciences , 2006,
Abstract: As microalgas s o utilizadas como fonte de alimento em aqüicultura. Neste trabalho cultivaram-se D. salina, T. chuii e I. galbana. O objetivo do trabalho consistiu em determinar o efeito do meio Erd Schreiber sobre o seu crescimento. Iniciou-se o cultivo com a mistura de 200 mg de Na2HPO4,7H2O, 100 mg de NaNO3 e 50 mL de extrato de solo. No monitoramento, manteve-se a temperatura entre 24 - 28 oC, a salinidade a 34 ppt, à ilumina o constante, a densidade celular com uma camara de Neubauer e um microscópio binocular modelo ZEISS. Como resultado, I. galbana, D. salina e T. chuii atingiram 969 104 cel/mL, 457 x 104 cel/mL e 258,66 x 104 cel/mL, respectivamente, e oscoeficientes angulares b foram 3,76 x 104 cel./mL/dia, 6,84 x 104 cel./mL/dia e 2,08 x 104 cel./mL/dia respectivamente, indicando bom desempenho de todas as microalgas no meio Erd Shreiber. The microalgae is used as food source in aqüicultura. In this work they had cultivated D. salina , T. chuii and I. galbana . The objective of the work is to determine the effect of Erd Schreiber′s culture medium on the microalgae growth. The culture initiated mixting 200mg of Na2HPO4,7H2O, 100 mg of NaNO3 and 50 mL of soil extract. During the culture the temperature had varied between 24 and 28oC, the salinity was fixed on 34 %o, and the illumination was maintained constant. The assessment of the culture was made by a chamber of Neubauer and a binocular microscope ZEISS model. As result I. galbana D. salina and T.chuii reached 969 104 cel/mL, 457 x 104cel/mL and 258,66 x 104 cel/mL respectively and as angular coefficient 3,76 x 104 cel/mL/dia, 6,84 x 104 cel/mL/dia and 2,08 104 x cel/mL/dia respectively, showing good answer of the microalgae to the effect of Erd Schreiber′ s medium.
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