Claudio Fuentes-Grünewald

Evaluation of batch and semi-continuous culture of Porphyridium purpureum in a photobioreactor in high latitudes using Fourier Transform Infrared spectroscopy for monitoring biomass composition and metabolites production.

The culture strategy (batch or semi-continuous) was evaluated for biomass and metabolite formation in Porphyridium purpureum cultures in higher latitudes (>50° N). FTIR was used technology to characterise macromolecule biomass composition and the quality of the metabolites produced. Semi-continuous culture was found to be the most feasible strategy to develop microalgal biomass production facilities in higher latitudes, due to their average results in terms of growth rate (0.27 day(-1)), duplication time (2.5-4 days), maximum cell density achieved (1.43*10(7) cells m L(-1)), biomass productivity of 47.04 mg L(-1) day(-1) and an exopolysaccharides production of 2.1 g L(-1). FTIR technology applied to microalgal production is a valuable and reliable tool to determine on a daily basis not just the evolution of macromolecules composition (lipids, carbohydrates and proteins) but also for the characterisation of the metabolites produced such as phycoerythrin or exopolysaccharides in P. purpureum cultures.

Utilising light-emitting diodes of specific narrow wavelengths for the optimization and co-production of multiple high-value compounds in Porphyridium purpureum

The effect of specific narrow light-emitting diode (LED) wavelengths (red, green, blue) and a combination of LED wavelengths (red, green and blue - RGB) on biomass composition produced by Porphyridium purpureum is studied. Phycobiliprotein, fatty acids, exopolysaccharides, pigment content, and the main macromolecules composition were analysed to determine the effect of wavelength on multiple compounds of commercial interest. The results demonstrate that green light plays a significant role in the growth of rhodophyta, due to phycobiliproteins being able to harvest green wavelengths where chlorophyll pigments absorb poorly. However, under multi-chromatic LED wavelengths, P. purpureum biomass accumulated the highest yield of valuable products such as eicosapentaenoic acid (∼2.9% DW), zeaxanthin (∼586μgg-1DW), β-carotene (397μgg-1DW), exopolysaccharides (2.05g/L-1), and phycobiliproteins (∼4.8% DW). This increased accumulation is likely to be the combination of both photo-adaption and photo-protection, under the combined specific wavelengths employed.

Long-term dinoflagellate culture performance in a commercial photobioreactor: Amphidinium carterae case.

The aim of this work was to study the culture performance of a dinoflagellate in a commercial photobioreactor. The results obtained during this long-term experiment allow to confirm that Amphidinium carterae is a promising dinoflagellate that can be exploited successfully in closed systems, in semi-continuous mode in indoor and outdoor environments. The average results in an indoor 5cm light-path 320L photobioreactor were, in terms of specific growth rate (0.29d(-1)), duplication time (3.1d(-1)) and dry biomass productivity (78mgL(-1)d(-1)). Specific compounds production was found including ω3 and ω6 fatty acids and, pigments (Peridinin, β-carotene). These promising results, besides unique characteristics found during the exploitation period such as resistance to mechanical stress, self-control of contaminant organisms, and quick cells aggregation when the culture is not in turbulence conditions, makes A. carterae one of the new target species suitable for commercially exploitation on an industrial scale.

Comparing Nutrient Removal from Membrane Filtered and Unfiltered Domestic Wastewater Using Chlorella vulgaris

The nutrient removal efficiency of Chlorella vulgaris cultivated in domestic wastewater was investigated, along with the potential to use membrane filtration as a pre-treatment tool during the wastewater treatment process. Chlorella vulgaris was batch cultivated for 12 days in a bubble column system with two different wastewater treatments. Maximum uptake of 94.18% ammonium (NH4-N) and 97.69% ortho-phosphate (PO4-P) occurred in 0.2 μm membrane filtered primary wastewater. Membrane filtration enhanced the nutrient uptake performance of C. vulgaris by removing bacteria, protozoa, colloidal particles and suspended solids, thereby improving light availability for photosynthesis. The results of this study suggest that growing C. vulgaris in nutrient rich membrane filtered wastewater provides an option for domestic wastewater treatment to improve the quality of the final effluent.

Long-term dinoflagellate culture performance in a commercial photobioreactor

The aim of this work was to study the culture performance of a dinoflagellate in a commercial photobioreactor. The results obtained during this long-term experiment allow to confirm that Amphidinium carterae is a promising dinoflagellate that can be exploited successfully in closed systems, in semi-continuous mode in indoor and outdoor environments. The average results in an indoor 5cm light-path 320L photobioreactor were, in terms of specific growth rate (0.29d(-1)), duplication time (3.1d(-1)) and dry biomass productivity (78mgL(-1)d(-1)). Specific compounds production was found including ω3 and ω6 fatty acids and, pigments (Peridinin, β-carotene). These promising results, besides unique characteristics found during the exploitation period such as resistance to mechanical stress, self-control of contaminant organisms, and quick cells aggregation when the culture is not in turbulence conditions, makes A. carterae one of the new target species suitable for commercially exploitation on an industrial scale.