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Rene H Wijffels - One of the best experts on this subject based on the ideXlab platform.
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Effect of cooling in the night on the productivity and biochemical composition of Tetraselmis Suecica
Algal Research-Biomass Biofuels and Bioproducts, 2014Co-Authors: Michiel H A Michels, M H Vermue, J. Camacho-rodríguez, Rene H WijffelsAbstract:The effect of cooling at night on the 24 hour productivity and biochemical composition of Tetraselmis Suecica cultivated in a tubular photobioreactor was determined. The hypothesis that cooling at night would decrease the night respiration rate and therefore enhance the net productivity was rejected. The productivity over a 24 hour period and biochemical composition were only influenced by the daily light input. Higher carbohydrate and lower protein content were observed in periods with more light. Carbohydrates produced during daylight were used for the protein synthesis at night, while the fatty acid content stayed constant during the day. The rate of carbohydrate loss at night was linearly related to the specific growth rate and therefore to the light history of the microalgae.
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Growth of Tetraselmis Suecica in a tubular photobioreactor on wastewater from a fish farm
Water Research, 2014Co-Authors: Michiel H A Michels, M H Vermue, Mitra Vaskoska, Rene H WijffelsAbstract:Wastewater from a fish farm was remediated in a continuously operated tubular photobioreactor in which Tetraselmis Suecica was cultured. The N and P removal efficiencies and the productivity of T. Suecica growing on the wastewater were determined. Possibilities to optimize the productivity by adding extra orthophosphate were investigated. At a biomass concentration of 0.5 g L(-1) on only wastewater, the N and P removal efficiencies were 49.4% and 99.0%, respectively. When extra phosphate was dosed to the wastewater, a 95.7% N removal efficiency and a 99.7% P removal efficiency could be reached at a biomass concentration of 1.0 g L(-1). This also resulted in significantly higher average net volumetric productivity ranging from 0.35 g L(-1) d(-1) at a biomass concentration of 0.5 g L(-1) to 0.46 and 0.52 g L(-1) d(-1) at biomass concentrations of 0.75 and 1.0 g L(-1), respectively. This study shows the feasibility of an integrated multi-trophic aquaculture approach where wastewater from the fish farms is used to produce feed for juvenile shellfish at high productivity and constant quality.
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effect of biomass concentration on the productivity of Tetraselmis Suecica in a pilot scale tubular photobioreactor using natural sunlight
Algal Research-Biomass Biofuels and Bioproducts, 2014Co-Authors: Michiel H A Michels, P M Slegers, M H Vermue, Rene H WijffelsAbstract:Abstract The effect of biomass concentration on the net volumetric productivity, yield on light and nightly biomass loss rate of Tetraselmis Suecica was studied using a pilot-scale tubular photobioreactor (PBR) under outdoor light conditions. The net average productivity and yield on light of Tetraselmis Suecica were optimal at a biomass concentration of 0.7 g L − 1 . Cultures grown at higher biomass concentrations showed a prolonged respiration period at low light periods, while light was wasted in more dilute cultures at high light intensities. At optimal biomass concentration of 0.7 g L − 1 the highest average net productivity and yield on light were 0.35 ± 0.03 g L − 1 d − 1 and 1.19 ± 0.15 g mol − 1 , respectively. The highest nightly biomass loss rate was measured for Tetraselmis Suecica grown at an optimal biomass concentration, which can be explained by higher maintenance costs of the microalgae with a higher growth rate. This study shows that the productivity and yield on light can be enhanced by optimizing the biomass concentration.
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Vitamin E (alpha-tocopherol) production by the marine microalgae Dunaliella tertiolecta and Tetraselmis Suecica in batch cultivation.
Biomolecular engineering, 2003Co-Authors: Eira C Carballo-cárdenas, Pham Minh Tuan, Marcel Janssen, Rene H WijffelsAbstract:Batch experiments with Dunaliella tertiolecta and Tetraselmis Suecica were performed to investigate alpha-tocopherol (alpha-T) production in time, in order to assess the effect of light availability per cell on the production of this antioxidant. In D. tertiolecta alpha-T content increased during growth, in other words, as the cell density increased and the light availability per cell decreased. In T. Suecica the pattern was different: alpha-T content was highest during the exponential phase, decreased significantly during the linear phase and increased again towards the end of the cultivation. Chlorophyll (chl-a) content of T. Suecica cells decreased after the exponential phase, instead of the expected increase typically observed in shade-adapted cells, suggesting that the culture was nutrient limited. An experiment with extra nutrients showed that chl-a and alpha-T content increased significantly during both the linear and the stationary phase when compared with values in nutrient-deficient conditions. No correlation between alpha-T and chl-a was observed. Our results indicate that diminished light availability does not limit alpha-T production in D. tertiolecta and T. Suecica, opening up the possibility of using high cell density, light-limited cultures for the production of this commercially interesting compound.
Michiel H A Michels - One of the best experts on this subject based on the ideXlab platform.
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Effect of cooling in the night on the productivity and biochemical composition of Tetraselmis Suecica
Algal Research-Biomass Biofuels and Bioproducts, 2014Co-Authors: Michiel H A Michels, M H Vermue, J. Camacho-rodríguez, Rene H WijffelsAbstract:The effect of cooling at night on the 24 hour productivity and biochemical composition of Tetraselmis Suecica cultivated in a tubular photobioreactor was determined. The hypothesis that cooling at night would decrease the night respiration rate and therefore enhance the net productivity was rejected. The productivity over a 24 hour period and biochemical composition were only influenced by the daily light input. Higher carbohydrate and lower protein content were observed in periods with more light. Carbohydrates produced during daylight were used for the protein synthesis at night, while the fatty acid content stayed constant during the day. The rate of carbohydrate loss at night was linearly related to the specific growth rate and therefore to the light history of the microalgae.
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Growth of Tetraselmis Suecica in a tubular photobioreactor on wastewater from a fish farm
Water Research, 2014Co-Authors: Michiel H A Michels, M H Vermue, Mitra Vaskoska, Rene H WijffelsAbstract:Wastewater from a fish farm was remediated in a continuously operated tubular photobioreactor in which Tetraselmis Suecica was cultured. The N and P removal efficiencies and the productivity of T. Suecica growing on the wastewater were determined. Possibilities to optimize the productivity by adding extra orthophosphate were investigated. At a biomass concentration of 0.5 g L(-1) on only wastewater, the N and P removal efficiencies were 49.4% and 99.0%, respectively. When extra phosphate was dosed to the wastewater, a 95.7% N removal efficiency and a 99.7% P removal efficiency could be reached at a biomass concentration of 1.0 g L(-1). This also resulted in significantly higher average net volumetric productivity ranging from 0.35 g L(-1) d(-1) at a biomass concentration of 0.5 g L(-1) to 0.46 and 0.52 g L(-1) d(-1) at biomass concentrations of 0.75 and 1.0 g L(-1), respectively. This study shows the feasibility of an integrated multi-trophic aquaculture approach where wastewater from the fish farms is used to produce feed for juvenile shellfish at high productivity and constant quality.
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effect of biomass concentration on the productivity of Tetraselmis Suecica in a pilot scale tubular photobioreactor using natural sunlight
Algal Research-Biomass Biofuels and Bioproducts, 2014Co-Authors: Michiel H A Michels, P M Slegers, M H Vermue, Rene H WijffelsAbstract:Abstract The effect of biomass concentration on the net volumetric productivity, yield on light and nightly biomass loss rate of Tetraselmis Suecica was studied using a pilot-scale tubular photobioreactor (PBR) under outdoor light conditions. The net average productivity and yield on light of Tetraselmis Suecica were optimal at a biomass concentration of 0.7 g L − 1 . Cultures grown at higher biomass concentrations showed a prolonged respiration period at low light periods, while light was wasted in more dilute cultures at high light intensities. At optimal biomass concentration of 0.7 g L − 1 the highest average net productivity and yield on light were 0.35 ± 0.03 g L − 1 d − 1 and 1.19 ± 0.15 g mol − 1 , respectively. The highest nightly biomass loss rate was measured for Tetraselmis Suecica grown at an optimal biomass concentration, which can be explained by higher maintenance costs of the microalgae with a higher growth rate. This study shows that the productivity and yield on light can be enhanced by optimizing the biomass concentration.
Mario R. Tredici - One of the best experts on this subject based on the ideXlab platform.
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Tetraselmis Suecica F&M-M33 growth is influenced by its associated bacteria.
Microbial Biotechnology, 2017Co-Authors: Natascia Biondi, Liliana Rodolfi, Giulia Cheloni, Luciana Giovannetti, Carlo Viti, Mario R. TrediciAbstract:Summary Algal cultures are usually co-cultures of algae and bacteria, especially when considering outdoor mass cultivation. The influence of associated bacteria on algal culture performance has been poorly investigated, although bacteria may strongly affect biomass (or derived product) yield and quality. In this work, the influence on growth and productivity of Tetraselmis Suecica F&M-M33 of bacterial communities and single bacterial isolates from the algal phycosphere was investigated. Xenic laboratory and outdoor cultures were compared with an axenic culture in batch. The presence of the bacterial community significantly promoted culture growth. Single bacterial isolates previously found to be strictly associated with T. Suecica F&M-M33 also increased growth compared with the axenic culture, whereas loosely associated and common seawater bacteria induced variable growth responses, from positive to detrimental. The increased growth was mainly evidenced as increased algal biomass production and cell size, and occurred after exhaustion of nutrients. This finding is of interest for biofuel production from microalgae, often attained through nutrient starvation processes leading to oil or carbohydrate accumulation. As axenic T. Suecica F&M-M33 showed a similar growth with or without vitamins, the most probable mechanism behind bacterial positive influence on algal growth seems nutrient recycling.
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The bacterial community associated with Tetraselmis Suecica outdoor mass cultures
Journal of Applied Phycology, 2017Co-Authors: Natascia Biondi, Liliana Rodolfi, Giulia Cheloni, Enrico Tatti, Francesca Decorosi, Luciana Giovannetti, Carlo Viti, Mario R. TrediciAbstract:Interactions between algae and associated bacterial communities in the phycosphere depend on many factors such as culture age, nutrient availability, and antibiotic production and greatly influence algal survival and growth. The microbial community associated with the marine microalga Tetraselmis Suecica F&M-M33 in a laboratory culture and an outdoor mass culture, set up from the laboratory one, run during a whole year was investigated in different seasons through isolation in pure culture of bacteria, amplified ribosomal DNA restriction analysis (ARDRA) of all the isolates, and terminal restriction fragment length polymorphism (T-RFLP) analysis. The total number of bacterial isolates was 152, which clustered in thirty-six 16S rDNA groups by ARDRA. Sequencing of a representative of each ARDRA group permitted identification of bacterial genera never reported before in association with microalgae in outdoor mass cultures, although most of them were previously found to be associated with the marine environment (e.g., seawater, sea sediments). T-RFLP analysis revealed that spring and autumn bacterial community profiles were closely related, while the bacterial laboratory community was considerably different (less than 50 % similarity) from that associated with the outdoor culture in different seasons. T-RFLP results suggest the presence of a core of bacteria that are closely associated with the alga and of a part of the community which varies seasonally.
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Growth, photosynthetic efficiency, and biochemical composition of Tetraselmis Suecica F&M-M33 grown with LEDs of different colors.
Biotechnology and Bioengineering, 2013Co-Authors: Fabian Abiusi, Liliana Rodolfi, Natascia Biondi, Giacomo Sampietro, Giovanni Marturano, Massimo D'ottavio, Mario R. TrediciAbstract:The effect of light quality on cell size and cell cycle, growth rate, productivity, photosynthetic efficiency and biomass composition of the marine prasinophyte Tetraselmis Suecica F&M-M33 grown in 2-L flat panel photobioreactors illuminated with light emitting diodes (LEDs) of different colors was investigated. Biomass productivity and photosynthetic efficiency were comparable between white and red light, while under blue and green light productivity decreased to less than half and photosynthetic efficiency to about one third. Differences in cell size and number correlated with the cell cycle phase. Under red light cells were smaller and more motile. Chlorophyll content was strongly reduced with red and enhanced with blue light, while carotenoids and gross biomass composition were not affected by light quality. The eicosapentaenoic acid content increased under red light. Red light can substitute white light without affecting productivity of T. Suecica F&M-M33, leading to smaller and more motile cells and increased eicosapentaenoic acid content. Red LEDs can thus be profitably used for the production of this microalga for aquaculture.
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Effect of the Inclusion of Dried Tetraselmis Suecica on Growth, Feed Utilization, and Fillet Composition of European Sea Bass Juveniles Fed Organic Diets
Journal of Aquatic Food Product Technology, 2012Co-Authors: Francesca Tulli, Bianca Maria Poli, G. Chini Zittelli, G. Giorgi, Emilio Tibaldi, Mario R. TrediciAbstract:Dried Tetraselmis Suecica was evaluated as a fish protein substitute when incorporated to replace (protein basis) 10% (TETRA10) and 20% (TETRA20) of the control diet. The diets were offered to nine groups of European sea bass (72 g) over 63 days. Test diets did not affect zootechnical performances nor carcass or fillet yields and proximate analysis of edible portion. Feeding TETRA20 resulted in lower apparent digestibility coefficients of protein, lipid, and organic matter, and hepatosomatic index compared to the control diet. T. Suecica was able to replace up to 20% of fish protein without hampering growth performance and major quality traits of sea bass.
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Oil production by the marine microalgae Nannochloropsis sp. F&M-M24 and Tetraselmis Suecica F&M-M33
Bioresource Technology, 2012Co-Authors: Paolo Bondioli, Laura Della Bella, Gabriele Rivolta, Graziella Chini Zittelli, Niccolò Bassi, Liliana Rodolfi, David Casini, Matteo Prussi, David Chiaramonti, Mario R. TrediciAbstract:Nannochloropsis sp. F&M-M24 and Tetraselmis Suecica F&M-M33 were cultivated outdoors in Green Wall Panels under nutrient deficiency to stimulate oil synthesis. Under nitrogen deprivation, Nannochloropsis attained average biomass and lipid productivities of 9.9 and 6.5 g m(-2) day(-1), respectively. Starved Tetraselmis cultures achieved a biomass productivity of about 7.6 g m(-2) day(-1) and a lipid productivity of 1.7 g m(-2) day(-1). Lipids represented 39.1% and 68.5% of non-starved and starved Nannochloropsis biomass, respectively. Starvation did not increase lipid content in Tetraselmis biomass. Important differences in lipid classes and in fatty acid composition were observed under the different cultivation conditions for both microalgae.
Peer M Schenk - One of the best experts on this subject based on the ideXlab platform.
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Induced carotenoid accumulation in Dunaliella salina and Tetraselmis Suecica by plant hormones and UV-C radiation.
Applied Microbiology and Biotechnology, 2015Co-Authors: Faruq Ahmed, Kent Fanning, Michael Netzel, Peer M SchenkAbstract: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.
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Isolation of High-Lipid Tetraselmis Suecica Strains Following Repeated UV-C Mutagenesis, FACS, and High-Throughput Growth Selection
Bioenergy Research, 2015Co-Authors: David K.y. Lim, Holger Schuhmann, Kalpesh Sharma, Peer M SchenkAbstract:Mutagenesis and selection of microalgae can be used for accelerated breeding of elite strains, providing a significant advantage over genetic engineering as prior biochemical and genetic information is not required. Ultraviolet (UV)-C-induced mutagenesis combined with fluorescence-activated cell sorting (FACS) and microtiter plate reader cell density screening was used to produce Tetraselmis Suecica strains with increased lipid contents without compromising on cell growth. After five rounds of mutation-selection, two dosages of UV-C (50 and > 98 % lethality) yielded two improved strains (M5 and M24) that produced significantly more neutral lipids (increases of 114 and 123 %, respectively). This study highlights that repeated UV-C mutagenesis and high-throughput selection for cell growth can be a viable combined approach to improve lipid productivity in microalgae. These maybe used as elite strains for future breeding programs and as potential feedstock for biodiesel production.
David K.y. Lim - One of the best experts on this subject based on the ideXlab platform.
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Isolation of High-Lipid Tetraselmis Suecica Strains Following Repeated UV-C Mutagenesis, FACS, and High-Throughput Growth Selection
Bioenergy Research, 2015Co-Authors: David K.y. Lim, Holger Schuhmann, Kalpesh Sharma, Peer M SchenkAbstract:Mutagenesis and selection of microalgae can be used for accelerated breeding of elite strains, providing a significant advantage over genetic engineering as prior biochemical and genetic information is not required. Ultraviolet (UV)-C-induced mutagenesis combined with fluorescence-activated cell sorting (FACS) and microtiter plate reader cell density screening was used to produce Tetraselmis Suecica strains with increased lipid contents without compromising on cell growth. After five rounds of mutation-selection, two dosages of UV-C (50 and > 98 % lethality) yielded two improved strains (M5 and M24) that produced significantly more neutral lipids (increases of 114 and 123 %, respectively). This study highlights that repeated UV-C mutagenesis and high-throughput selection for cell growth can be a viable combined approach to improve lipid productivity in microalgae. These maybe used as elite strains for future breeding programs and as potential feedstock for biodiesel production.