title: Action spectra of oxygen production and chlorophyll a fluorescence in the green microalga Nannochloropsis oculata.
abstract: The first complete action spectrum of oxygen evolution and chlorophyll a fluorescence was measured for the biofuel candidate alga Nannochloropsis oculata. A novel analytical procedure was used to generate a representative and reproducible action spectrum for microalgal cultures. The action spectrum was measured at 14 discrete wavelengths across the visible spectrum, at an equivalent photon flux density of 60 μmol photon sm(-2) s(-1). Blue light (∼ 414 nm) was absorbed more efficiently and directed to photosystem II more effectively than red light (∼ 679 nm) at light intensities below the photosaturation limit. Conversion of absorbed photons into photosynthetic oxygen evolution was maximised at 625 nm; however, this maximum is unstable since neighbouring wavelengths (646 nm) resulted in the lowest photosystem II operating efficiency. Identifying the wavelength-dependence of photosynthesis has clear implications to optimising growth efficiency and hence important economic implications to the algal biofuels and bioproducts industries.
authors: Plant Functional Biology and Climate Change Cluster (C3), University of Technology, Sydney, Broadway NSW 2007, Australia. Electronic address: bojan.tamburic@uts.edu.au.
authors: Bojan
authors: B
authors: Tamburic
authors: Plant Functional Biology and Climate Change Cluster (C3), University of Technology, Sydney, Broadway NSW 2007, Australia.
authors: Milán
authors: M
authors: Szabó
authors: School of the Environment, Faculty of Science, University of Technology, Sydney, Broadway NSW 2007, Australia.
authors: Nhan-An T
authors: NT
authors: Tran
authors: Plant Functional Biology and Climate Change Cluster (C3), University of Technology, Sydney, Broadway NSW 2007, Australia.
authors: Anthony W D
authors: AWD
authors: Larkum
authors: Plant Functional Biology and Climate Change Cluster (C3), University of Technology, Sydney, Broadway NSW 2007, Australia.
authors: David J
authors: DJ
authors: Suggett
authors: Plant Functional Biology and Climate Change Cluster (C3), University of Technology, Sydney, Broadway NSW 2007, Australia; School of the Environment, Faculty of Science, University of Technology, Sydney, Broadway NSW 2007, Australia.
authors: Peter J
authors: PJ
authors: Ralph
mesh_terms: D065966:Absorption, Physicochemical; D002734:Chlorophyll / Q000378:metabolism*; D000077194:Chlorophyll A; D005453:Fluorescence; D058086:Microalgae / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*; D017785:Photons; D010788:Photosynthesis; D013050:Spectrometry, Fluorescence; D058009:Stramenopiles / Q000378:metabolism*
chemical_list: D002734:Chlorophyll; D010100:Oxygen; D000077194:Chlorophyll A
keywords: Action spectrum; Algal biofuel; Chlorophyll fluorescence; Nannochloropsis oculata; Oxygen production