title: Effects of cell density, light intensity and mixing on Undaria pinnatifida gametophyte activity in a photobioreactor.
abstract: An on-line controlled 7 l sterilizable photobioreactor was used for the optimisation of a culture of gametophytes of Undaria pinnatifida. The gametophytes, which had been stored for three years in a culture cabinet at 16 degrees C, could rapidly grow in the photobioreactor under controlled conditions. The rate of increase of dissolved oxygen and pH were used to monitor the photosynthetic activity. Optimal gametophytes density changed varying the light intensity. The optimal cell densities were 3.24 and 3.45 g FW l(-1) when the cultures were exposed to 61.7 and 82.3 microE m(-2) s(-1), respectively. The optimal cell density was higher under a high photon flux density (PFD) than under low PFD. On the other hand, the optimal light intensities were different for different cell density cultures. The light saturation point was higher at high cell density cultures than at low cell density cultures. The optimal rotational speed was 150 rpm for high cell density culture in the photobioreactor.
authors.affiliation: Biology Department, Yantai Teachers' College, Yantai, Shandong province 264025, China. ningzou76@hotmail.com
authors.forename: Ning
authors.initials: N
authors.lastname: Zou
authors.forename: Baicheng
authors.initials: B
authors.lastname: Zhou
authors.forename: Bingjun
authors.initials: B
authors.lastname: Li
authors.forename: Donghong
authors.initials: D
authors.lastname: Sun
authors.forename: Chengkui
authors.initials: C
authors.lastname: Zeng
mesh_terms: D019149:Bioreactors / Q000382:microbiology*; D002452:Cell Count; D018929:Cell Culture Techniques / Q000379:methods*; D002498:Centrifugation / Q000379:methods; D004307:Dose-Response Relationship, Radiation; D005854:Germ Cells / Q000502:physiology* / Q000528:radiation effects*; D006863:Hydrogen-Ion Concentration; D008027:Light; D009862:Online Systems; D010100:Oxygen / Q000378:metabolism*; D010788:Photosynthesis / Q000502:physiology; D011786:Quality Control; D011829:Radiation Dosage; D013696:Temperature; D044648:Undaria / Q000502:physiology* / Q000528:radiation effects*
chemical_list: D010100:Oxygen