Fv/Fm, growth rate, diadinoxanthin (DD) and diatoxanthin (DT) content and de-epoxidation state (DES) of the WT and Dde transformants Phaeodactylum tricornutum grown under high light (HL).

Maximum photosynthetic efficiency of PSII (Fv/Fm), growth rate (μ in d−1), diadinoxanthin (DD) and diatoxanthin (DT) content (in mol/100 mol Chl a), and de-epoxidation state (DES) of the WT and the Dde transformants of P. tricornutum cells grown at HL (135 µmol photons⋅m−2⋅s−1). DD, DT and DES were determined before and after a 5 min 450 µmol photons⋅m−2⋅s−1 light treatment (LT). DES (in%) = DT/(DD+DT) ×100. Values are averages, ± SD of three measurements.