title: Phosphorus limitation and starvation effects on cell growth and lipid accumulation in Isochrysis galbana U4 for biodiesel production.
abstract: The effect of varying levels of phosphorus (P) on Isochrysis galbana U4 growth, pigmentation and lipid accumulation were investigated. A reduction in the P content to 25% of the recommended level for f/2 medium did not lead to declines in cell growth rates or lipid accumulation levels relative to the cultures maintained on medium supplemented with the normal P dose. Evidence suggesting that the recommended P supply in f/2 exceeds the requirements for maximal algal growth has obvious economic implications for the mass production of I. galbana for biodiesel production. When P supply was in excess this species was also found to accumulate intracellular levels of P that exceeded by up to 6 times its P requirements for growth and cell division. The reduction in P concentration to levels below 25% resulted in P starvation stimulated chlorophyll reductions and carotenoid and lipid accumulation in this species.
authors.affiliation: School of Molecular and Cell Biology, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa. Electronic address: Ashira.Roopnarain@students.wits.ac.za.
authors.forename: A
authors.initials: A
authors.lastname: Roopnarain
authors.affiliation: School of Molecular and Cell Biology, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa.
authors.forename: V M
authors.initials: VM
authors.lastname: Gray
authors.affiliation: School of Animal, Plant and Environmental Science, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa.
authors.forename: S D
authors.initials: SD
authors.lastname: Sym
mesh_terms: D056804:Biofuels; D058087:Haptophyta / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism*; D050356:Lipid Metabolism / Q000187:drug effects*; D009566:Nitrates / Q000378:metabolism; D010758:Phosphorus / Q000172:deficiency* / Q000494:pharmacology; D010858:Pigmentation / Q000187:drug effects
chemical_list: D056804:Biofuels; D009566:Nitrates; D010758:Phosphorus
keywords: Isochrysis galbana U4 growth; Isochrysis galbana U4 lipid accumulation; Isochrysis galbana U4 pigmentation; Phosphorus accumulation in Isochrysis galbana U4