Strain selection and outdoor cultivation of halophilic microalgae with potential for large-scale biodiesel production

摘要: The focus of this study was to identify microalgae isolates suitable for long-term outdoor cultivation at high salinities biodiesel production. Screening and selection locally collected halophilic were based on the comparison phenotypic traits such as growth rate, photosynthetic response biomass productivity over a range salinities, temperatures, light intensities dissolved oxygen levels. Strain also carried out in open raceway ponds. The prasinophyte Tetraselmis benthic diatoms most abundant microalgal species isolated. Indoor comparative studies between 6 strains- MUR 167, 219, 230, 231, 232 233- diatom Amphora coffeaeformis 158 showed that more suited ponds. Disadvantages associated with A. lower salinity tolerance (up 5% NaCl only, compared 9% Tetraselmis), slower above all, inability outcompete cultures. Appreciable differences observed strains, 233 being promising strains cultivation. Based indoor determination Pmax values, Ik rates, lipid content oxygen, dominant strain, followed by 167. Out doors, 167 productive strain when cultivated However, 230 characterised consistent stable growth. Regardless variation, ponds significantly influenced water quality highest cell densities below 40 x 104 cells.mL-1, 12% temperature 20-25 °C. The appropriate choice solvent system, sample ratio laboratory techniques extraction highlighted study. modified Bligh Dyer method efficient extracting lipids from exponentially-grown cells Folch et al. method, whereas no difference both methods stationary phase. Final values employed gravimetric measurements content. In summary, is candidate large-scale better performance higher productivities can be achieved through careful optimum culture management regime. This underlined need critical assessment reported literature since many factors influence final content.