[ Objective] This study was to improve the biomass of Navicula tenera, and thus to provide reference for achieving the industrial production of Navicula tenera. [Method] The feasibility of using sewage to cultivate Na...[ Objective] This study was to improve the biomass of Navicula tenera, and thus to provide reference for achieving the industrial production of Navicula tenera. [Method] The feasibility of using sewage to cultivate Navicula tenera was preliminarily investigated based on the consideration of regional characteristics; and a series of culture conditions including the nutrient source of nitrogen（N）, phosphorus（P）, iron（Fe）, silicon（ Si ） and the salinity in medium for culturing Navicula tenera, were optimized by single factor test and orthogonal design.[Result] The optimized conditions for cultivating Navicula tenera using sewage are as follows： the water from Xiaoerlou Artificial Lake of Nanjing University of Technology as basic solvent; 360 mg/L urea; 150 mg/L N2HPO4 · 12H2O; 50 mg/L ferric citrate; 2 000 mg/L Na2SiO3 · 9H2O; 2.0 mol/L salinity. Navicula tenera was strongly adaptive to sewage and could well uptake the nutrient sources in the sewage. Under the optimized conditions, the culture cost decreased, and meanwhile the biomass of Navicula tenera reached 4. 766 g/L which is 3.57 multiples over original medium and 1.9 multiples over optimized medium No. 1.[ Conclusion] This study laid a foundation for the combination of culturing Navicula tenera in large scale and sewage treatment.展开更多
Four species in the genus Navicula were isolated using the serial dilution method. Based on scanning elec-tron microscopy （SEM） and sequence comparisons of two segments of genes （small ribosomal subunit and large s...Four species in the genus Navicula were isolated using the serial dilution method. Based on scanning elec-tron microscopy （SEM） and sequence comparisons of two segments of genes （small ribosomal subunit and large subunit of Rubisco）, the species were identified asNavicula perminuta,N. pseudacceptata,N. vara, andN. rhynchocephala. Based on phylogenetic analysis and culture trials,there was a close relationship betweenN. perminutaandN. vara. Growth of these species was evaluated using measurements of optical density at 680 nm （OD680） under various environmental factors. Results showed that the optimum culture conditions were 25°C, 50-100 μmol photons m-2 s-1, pH 8.0, and salinities from 25 to 30. However, the favor-able salinity forN. perminuta was surprisingly high at 35. Nutrient requirement analysis demonstrated that growth ofNavicula depended on the availability of SiO32-. Their relative growth rates （RGR） peaked at the highest tested level （0.25 mmol/L）. The optimal concentrations of NO3-and PO43- were 3.6 mmol/L and 0.18 mmol/L, respectively. Culture of theseNavicula species for abalone or sea cucumber aquaculture should take these factors into consideration.展开更多
基金Supported by National Basic Research Program of China(973 Pro-gram)(2003CB71600)~~
文摘[ Objective] This study was to improve the biomass of Navicula tenera, and thus to provide reference for achieving the industrial production of Navicula tenera. [Method] The feasibility of using sewage to cultivate Navicula tenera was preliminarily investigated based on the consideration of regional characteristics; and a series of culture conditions including the nutrient source of nitrogen（N）, phosphorus（P）, iron（Fe）, silicon（ Si ） and the salinity in medium for culturing Navicula tenera, were optimized by single factor test and orthogonal design.[Result] The optimized conditions for cultivating Navicula tenera using sewage are as follows： the water from Xiaoerlou Artificial Lake of Nanjing University of Technology as basic solvent; 360 mg/L urea; 150 mg/L N2HPO4 · 12H2O; 50 mg/L ferric citrate; 2 000 mg/L Na2SiO3 · 9H2O; 2.0 mol/L salinity. Navicula tenera was strongly adaptive to sewage and could well uptake the nutrient sources in the sewage. Under the optimized conditions, the culture cost decreased, and meanwhile the biomass of Navicula tenera reached 4. 766 g/L which is 3.57 multiples over original medium and 1.9 multiples over optimized medium No. 1.[ Conclusion] This study laid a foundation for the combination of culturing Navicula tenera in large scale and sewage treatment.
基金The National Natural Science Foundation of China under contract No.41176135
文摘Four species in the genus Navicula were isolated using the serial dilution method. Based on scanning elec-tron microscopy （SEM） and sequence comparisons of two segments of genes （small ribosomal subunit and large subunit of Rubisco）, the species were identified asNavicula perminuta,N. pseudacceptata,N. vara, andN. rhynchocephala. Based on phylogenetic analysis and culture trials,there was a close relationship betweenN. perminutaandN. vara. Growth of these species was evaluated using measurements of optical density at 680 nm （OD680） under various environmental factors. Results showed that the optimum culture conditions were 25°C, 50-100 μmol photons m-2 s-1, pH 8.0, and salinities from 25 to 30. However, the favor-able salinity forN. perminuta was surprisingly high at 35. Nutrient requirement analysis demonstrated that growth ofNavicula depended on the availability of SiO32-. Their relative growth rates （RGR） peaked at the highest tested level （0.25 mmol/L）. The optimal concentrations of NO3-and PO43- were 3.6 mmol/L and 0.18 mmol/L, respectively. Culture of theseNavicula species for abalone or sea cucumber aquaculture should take these factors into consideration.
