Bioactive compounds through anaerobic digestion of heterotrophic microalgae residues

Several important biomolecules are available into anaerobically digested effluents that were obtained from the biodiesel production process using heterotrophically grown microalga Chlorella protothecoides. Defatted microalgae residues and crude glycerol may undergo anaerobic digestion, separately and in admixture, providing methane/hydrogen and a digestate exploitable for agriculture applications. Furthermore, industrial interesting bioactive compounds such as polyphenols provided with antioxidant activity can be obtained. Anaerobic process offers a promising chance and can be advantageously combined with algae lipid-extraction techniques in order to make it more sustainable.

Anaerobic digestion process for biogas and biomolecules production: microflora identification and characterization

The anaerobic process was efficient in organic matter removal. During the process, an interesting compound as quercetin was produced inside of reactor. Phylogenetic analysis showed the presence of phylotypes affiliated with gamma-Proteobacteria, Choroflexi, and Bacteroidetes. Archaea were represented by phylotypes belonging to the genus Methanosarcina and Methanosaeta.

An electrochemical process for the production of synthetic fuels at low temperatures [Resumo]

Following work exploring the low temperature electrolysis in alkaline media, using graphite consumable anodes, from which syngas was obtained1, laboratory studies have been conducted in acid media pursuing higher efficiency in the production of hydrogen and synthetic fuels. Experiments were conducted in an own designed undivided planar cell with 25 cm2 geometrical area electrodes using a 0.5 M H2SO4 solution with and without Fe(II) additions. Fe2+ oxidizes to Fe3+ at the anode surface. The redox couple Fe3+/ Fe2+ acts as an oxidation mediator not only oxidizing the bulk and detached graphite but also the surface functional groups. The practical experimental potential for graphite oxidation is within the range for the electroxidation of the Fe redox couple giving as a result a 4-fold increase in the amount of produced CO2 at near room temperature, when using 0.025 M FeSO4.