title: Photosynthetic efficiency and rate of CO2 assimilation by Arthrospira (Spirulina) platensis continuously cultivated in a tubular photobioreactor.
abstract: Similar to other photosynthetic microorganisms, the cyanobacterium Arthrospira platensis can be used to produce pigments, single cell proteins, fatty acids (which can be used for bioenergy), food and feed supplements, and biofixation of CO(2) . Cultivation in a specifically designed tubular photobioreactor is suitable for photosynthetic biomass production, because the cultivation area can be reduced by distributing the microbial cells vertically, thus avoiding loss of ammonia and CO(2) . The aim of this study was to investigate the influence of light intensity and dilution rate on the photosynthetic efficiency and CO(2)  assimilation efficiency of A. platensis cultured in a tubular photobioreactor in a continuous process. Urea was used as a nitrogen source and CO(2)  as carbon source and for pH control. Steady-state conditions were achieved in most of the runs, indicating that continuous cultivation of this cyanobacterium in a tubular photobioreactor could be an interesting alternative for the large-scale fixation of CO(2)  to mitigate the greenhouse effect while producing high protein content biomass.
authors.affiliation: Department of Biochemical and Pharmaceutical Technology, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil.
authors.forename: Marcelo Chuei
authors.initials: MC
authors.lastname: Matsudo
authors.forename: Raquel Pedrosa
authors.initials: RP
authors.lastname: Bezerra
authors.forename: Sunao
authors.initials: S
authors.lastname: Sato
authors.forename: Attilio
authors.initials: A
authors.lastname: Converti
authors.forename: João Carlos Monteiro
authors.initials: JC
authors.lastname: de Carvalho
mesh_terms: D000704:Analysis of Variance; D018533:Biomass; D002245:Carbon Dioxide / Q000378:metabolism*; D058433:Photobioreactors / Q000382:microbiology*; D017785:Photons; D010788:Photosynthesis / Q000502:physiology; D011506:Proteins / Q000032:analysis / Q000378:metabolism; D053545:Spirulina / Q000254:growth & development* / Q000378:metabolism*; D014508:Urea / Q000378:metabolism
chemical_list: D011506:Proteins; D002245:Carbon Dioxide; D014508:Urea