title: Influence of the N:P supply ratio on biomass productivity and time-resolved changes in elemental and bulk biochemical composition of Nannochloropsis sp.
abstract: This work reports for the first time the detailed impacts of dual nitrogen (N) and phosphorus (P) stress on growth dynamics and biochemical composition in the Eustigmatophyte Nannochloropsis sp. P-stress concurrent with N-stress had subtle effects on culture bulk biochemical composition, but negatively influenced biomass productivity. However, the N:P supply ratio can be raised to at least 32:1 without compromising productivity (yielding a maximum lipid content of 52% of dry weight and volumetric lipid concentration of 233 mg L(-1)). The maximum biomass and lipid yields per unit of cell-P were 1.2 kg DW (gP)(-1) and 0.54 kg lipid (gP)(-1). The P concentration of many common media is thus in surplus for optimal Nannochloropsis sp. biomass and lipid production, offering potential for significant savings in P usage and improving the sustainability of algal cultivation.
authors.affiliation: Centre for Sustainable Aquatic Research, Swansea University, Swansea SA2 8PP, UK.
authors.forename: Joshua J
authors.initials: JJ
authors.lastname: Mayers
authors.affiliation: Centre for Sustainable Aquatic Research, Swansea University, Swansea SA2 8PP, UK. Electronic address: K.J.Flynn@swansea.ac.uk.
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Flynn
authors.affiliation: Centre for Sustainable Aquatic Research, Swansea University, Swansea SA2 8PP, UK.
authors.forename: Robin J
authors.initials: RJ
authors.lastname: Shields
mesh_terms: D061249:Batch Cell Culture Techniques; D018533:Biomass; D002452:Cell Count; D048429:Cell Size / Q000187:drug effects; D008055:Lipids / Q000096:biosynthesis; D009584:Nitrogen / Q000494:pharmacology*; D010758:Phosphorus / Q000494:pharmacology*; D058009:Stramenopiles / Q000166:cytology / Q000187:drug effects* / Q000254:growth & development* / Q000378:metabolism; D013997:Time Factors
chemical_list: D008055:Lipids; D010758:Phosphorus; D009584:Nitrogen
keywords: Lipid accumulation; Microalgae; Nannochloropsis sp.; Nitrogen deficiency; Phosphorus usage