title: Influence of ammonium chloride feeding time and light intensity on the cultivation of Spirulina (Arthrospira) platensis.
abstract: This study dealt with the influence of both the feeding time and light intensity on the fed-batch culture of the cyanobacterium Spirulina (Arthrospira) platensis using ammonium chloride as a nitrogen source. For this purpose, a 2(2) plus star central composite experimental design combined with response surface methodology was employed, and the maximum cell concentration (X(m)), the cell productivity (P(X)), and the yield of biomass on nitrogen (Y(X/N)) were selected as the response variables. The optimum values of X(m) (1,833 mg L(-1)) and Y(X/N) (5.9 g g(-1)) estimated by the model at light intensity of 13 klux and feeding time of 17.2 days were very close to those obtained experimentally under these conditions (X(m) = 1,771 +/- 41 mg L(-1); Y(X/N) = 5.7 +/- 0.17 g g(-1)). The cell productivity was a decreasing function of the ammonium chloride feeding time and a quadratic function of the light intensity. The protein and lipid contents of dry biomass collected at the end of cultivations were shown to decrease with increasing light intensity.
authors: Department of Biochemical and Pharmaceutical Technology, Faculty of Pharmaceutical Sciences, University of São Paulo, Av. Prof. Lineu Prestes, 580, B-16, São Paulo 05508-900, Brazil.
authors: Raquel Pedrosa
authors: RP
authors: Bezerra
authors: Marcelo Chuei
authors: MC
authors: Matsudo
authors: Attilio
authors: A
authors: Converti
authors: Sunao
authors: S
authors: Sato
authors: João Carlos Monteiro
authors: JC
authors: de Carvalho
mesh_terms: D000643:Ammonium Chloride / Q000378:metabolism*; D019149:Bioreactors / Q000382:microbiology*; D018929:Cell Culture Techniques / Q000379:methods*; D049109:Cell Proliferation / Q000528:radiation effects; D002470:Cell Survival / Q000187:drug effects; D003198:Computer Simulation; D004307:Dose-Response Relationship, Radiation; D008954:Models, Biological; D011829:Radiation Dosage; D053545:Spirulina / Q000166:cytology / Q000502:physiology* / Q000528:radiation effects*; D013997:Time Factors
chemical_list: D000643:Ammonium Chloride