title: High cell density culture of Anabaena variabilis with controlled light intensity and nutrient supply.
abstract: Controlling the light energy and major nutrients is important for high cell density culture of cyanobacterial cells. The growth phase of Anabaena variabilis can be divided into an exponential growth phase and a deceleration phase. In this study, the cell growth in the deceleration phase showed a linear growth pattern. Both the period of the exponential growth phase and the average cell growth rate in the deceleration phase increased by controlling the light intensity. To control the light intensity, the specific irradiation rate was maintained above 10 micromol/s/g dry cell by increasing the incident light intensity stepwise. The final cell density increased by controlling the nutrient supply. For the control of the nutrient supply, nitrate, phosphate, and sulfate were intermittently added based on the growth yield, along with the combined control of light intensity and nutrient concentration. Under these control conditions, both final cell concentration and cell productivity increased, to 8.2 g/l and 1.9 g/l/day, respectively.
authors.affiliation: School of Chemical and Biological Engineering, Institute of Bioengineering, Seoul National University, Seoul 151-744, Korea.
authors.forename: Jong Hyun
authors.initials: JH
authors.lastname: Yoon
authors.forename: Jong-Hwan
authors.initials: JH
authors.lastname: Shin
authors.forename: Eun Kyung
authors.initials: EK
authors.lastname: Ahn
authors.forename: Tai Hyun
authors.initials: TH
authors.lastname: Park
mesh_terms: D046870:Anabaena variabilis / Q000254:growth & development* / Q000378:metabolism / Q000528:radiation effects; D018533:Biomass; D019149:Bioreactors / Q000382:microbiology; D018929:Cell Culture Techniques / Q000379:methods*; D003470:Culture Media / Q000737:chemistry; D008027:Light; D009566:Nitrates / Q000378:metabolism*; D010710:Phosphates / Q000378:metabolism*; D013431:Sulfates / Q000378:metabolism*
chemical_list: D003470:Culture Media; D009566:Nitrates; D010710:Phosphates; D013431:Sulfates