The microalga Nannochloropsis sp. was used in this study, in a biorefinery context, as biomass feedstock for the production of fatty acids for biodiesel, biohydrogen and high added-value compounds. The microalgal biomass, which has a high lipid and pigment content (mainly carotenoids), was submitted to supercritical CO2 extraction. The temperature, pressure and solvent flow-rate were evaluated to check their effect on the extraction yield. The best operational conditions to extract 33 g lipids/100 g dry biomass were found to be at 40 °C, 300 bar and a CO2 flow-rate of 0.62 g/min. The effect of adding a co-solvent (ethanol) was also studied. When supercritical CO2 doped with 20% (w/w) ethanol was used, it was possible to extract 45 g lipids/100 g dry biomass of lipids and recover 70% of the pigments. Furthermore, the remaining biomass after extraction was effectively used as feedstock to produce biohydrogen through dark fermentation by Enterobacter aerogenes resulting in a hydrogen production yield of 60.6 mL/g dry biomass.

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The present text describes a method for the isolation by solid phase extraction of the purple pigment present in D. congesti¯ora heartwood. It also presents the procedure applied to obtain maximum pigment extraction. Purple pigment quanti®cation was carried out by densitometry, showing that its concentration in the heartwood of D. congesti¯ora amounted to approximately 4.85% of dry matter. Bestimmung des Purpur-Farbstoffs im Kernholz von Dalbergia congestiflora PittierEs wird eine Methode beschrieben, den Purpur-Farbstoff im Kernholz von Dalbergia congesti¯ora in maximaler Ausbeute zu gewinnen. Die Isolierung erfolgte mittels einer Festphasenextraktion auf einer Si-2OH Sa Èule. Die densitrometrische Bestimmung wurde mittels HPTLC auf Kieselgel-beschichteten Platten durchgefu Èhrt. Die Ergebnisse zeigten, daû der reine Farbstoff in einer Konzentration von 4,85%. im Kernholz vorliegt. ResultsThe maximum portion of alcoholic extract that can be obtained was determined to amount 24.25% in relation to dry wood.

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