## 2 Materials and Methods
### Biochemical Composition  
The biochemical composition was performed with biomass grown until the latest exponential phase, which was freeze dried prior to analysis. Elemental analysis of C, H and N were performed using a Vario EL III (Vario EL, Elementar Analyser System, GmbH, Hanau, Germany) according to the manufacturer's procedure. Total proteins were calculated by multiplying the \(N\) content given by elemental analysis with the standard conversion factor of 6.25 [24].  
Total lipid content was determined following the Bligh & Dyer [25] method with some modifications [15]. Briefly, biomass was extracted with a mixture of chloroform, methanol, and water (1:2:0.8, v:v:v) and homogenized with an IKA Ultra-Turrax disperser (IKA-Werke GmbH, Staufen, Germany) on ice for 60 s. Centrifugation allowed phase separation and the organic phase was transferred to new vessels. Afterwards, a known volume (0.7 mL) was pipetted to pre-weighed tubesand evaporated at 60 \({}^{\circ}\)C. The resulting dried residue was weighed and compared with the DW to provide an accurate determination of the lipid fraction.  
The ash content was determined by the weight difference before and after the combustion of the biomass. Biomass was heated at 550 \({}^{\circ}\)C during 8 h using a furnace ([PERSON], Sell horn R9-L, Barcelona, Spain).  
Carbohydrates were calculated by the difference of the other macronutrients analyzed.  
Fatty acids were converted into the corresponding fatty acid methyl esters (FAME) according to [PERSON] & Roy [26] protocol, modified by [PERSON] et al. [15]. FAME were analyzed in a gas chromatography-mass spectrometry (GC-MS) analyzer (Bruker SCION 456/GC, SCION TQ MS) equipped with a ZB-5 MS capillary column (30 m \(\times\) 0.25 mm of internal diameter, 0.25 \(\upmu\)m of film thickens, Phenomenex), using helium as the carrier gas. The temperature program was 60 \({}^{\circ}\)C for 1 min, 30 \({}^{\circ}\)C-min\({}^{-1}\) to 120 \({}^{\circ}\)C, 5 \({}^{\circ}\)C-min\({}^{-1}\) to 250 \({}^{\circ}\)C and final increase of 20 \({}^{\circ}\)C-min\({}^{-1}\) to 300 \({}^{\circ}\)C. Injection temperature was 300 \({}^{\circ}\)C. For identification and quantification of FAME, five different concentrations of the standards Supelco(r) 37 component FAME Mix 41 (Sigma-Aldrich, Sintra, Portugal) were analyzed in order to establish calibration curves for each of the standard.  
For pigments extraction, 10 mg of fresh biomass was extracted with glass beads in 6 mL of acetone for 10 min. The sample was centrifuged (HERMLE Z300, New York, NY, USA) at 3500 rpm for 10 min until complete loss of the pellet color. The supernatant was analyzed using a spectrophotometer (Genesys 10S UV-VIS, MA, USA) in the scanning spectrum (380 to 700 nm) and the data were analyzed by the Excel Add-In Solver on Windows 2013.  
Carotenoid profiles were determined according to [PERSON] et al. [27]. Briefly, the extract was completely dried under nitrogen flow, resuspended in high-performance liquid chromatography (HPLC)-grade methanol and filtered (0.22 \(\upmu\)m) into an amber HPLC vial. The separation and chromatographic analysis of pigments were performed by Merck Hitachi LaCrom Elite HPLC (Darmstadt, Germany) equipped with a diode-array detector, using a LiChroCART RP-18 (5 \(\upmu\)m, 250 \(\times\) 4 mm, LiChrospher) column and a flow rate of 1 mL-min\({}^{-1}\). The mobile phase consisted of ethyl acetate as solvent A and 9:1 (v:v) acetonitrile:water as solvent B. The gradient program applied was: 0-16 min, 0%-60% A; 16-30 min, 60% A; 30-32 min, 100% A and 30-35 min 100% B. The injection volume was 100 \(\upmu\)L. Quantification of pigments was carried out at 450 nm using calibration curves of the pigment standards neoxanthin, violaxanthin, lutein and \(\beta\)-carotene. The HPLC chromatogram with carotenoids retention times (Figure S1) and respective calibration curves of pigment standards (Figures S2-S5) is given in Supplementary Materials.