An investigation into the ecophysiology of Haematococcus pluvialis and Chlorella sorokiniana grown in continuous photobioreactors

• Grant number: 11/09694-0
• Support type: Regular Research Grants
• Duration: October 01, 2011 - September 30, 2013
• Field of knowledge: Biological Sciences - Botany - Applied Botany
• Principal researcher: Ana Teresa Lombardi
• Grantee: Ana Teresa Lombardi
• Home Institution: Centro de Ciências Biológicas e da Saúde (CCBS). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Assoc. researchers: Maria da Graça Gama Melão ; Maria Teresa Maldonado Pareja ; Patricia Franklin Mayrink Nogueira ; Paula Cristina Garcia Manoel Crnkovic ; Sergio Rodrigues Fontes

Abstract

Microalgae are promising resources for new products with applications in the food, cosmetic, pharmacy and biofuel industries. Nevertheless, just few species are grown in large scale and, among these, the culture options that prevail are open raceway tanks. This is because open tanks are cheaper and of easier operation and maintainance when compared with closed photobioreactors. However, due to the high contamination potential and low physiological control of the microalgae in open tanks, its use for the production of pure compounds for the pharmacy and/or food industries is not recommended. In such cases, closed continuous photobioreactors are prefered because they offer physiological control of the algae cells and cultures are less prone to contamination. The biochemical manipulation of microalgae requires stable and controlable ecophysiological conditions that continuous cultures offer, in contrast to batch systems operated in the open tanks. In the present proposal we aim the construction of 3 photobioreactors to be operated in continuous systems, two of which with 3 L capacity and one with 30 L capacity to grow phytoplankton cells with high ecophysiological control. This will lead to precise manipulation of the biochemical composition of the algae. Our research will be supported by algae physiology through the determination of photosynthetic efficiency (modulated fluorescence, PhytoPAM) associated with the application of environmental stresses (different phosphate and copper concentrations) for oriented biomolecules synthesis. The biochemical composition of the cells include the determination of total carbohydrates and proteins concentrations, and lipid class analysis (TLC/FID, Iatroscan). Thermal analysis (calorimetry, thermogravimetry and differential thermal analysis) will also be performed in the biomass. Two freshwater green algae known to have comercial interest, Haematococcus pluvialis (astaxantin producer) and Chlorella sorokiniana (protein source in aquaculture) will be investigated in this study. The microalgae will be used as food source for zooplankton, which have high nutritional value for fish larvae in aquaculture. This research inovates in two important aspects, first it associates the photosynthetic monitoring with variables that can induce the synthesis of biochemical compounds of interest and, secondly, the use of culture systems that offer highly controlled physiological conditions aiming higher yield and microalgae production. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

CHIA, MATHIAS AHII; LOMBARDI, ANA TERESA; GAMA MELAO, MARIA DA GRACA; PARRISH, CHRISTOPHER C. Effects of cadmium and nitrogen on lipid composition of Chlorella vulgaris (Trebouxiophyceae, Chlorophyta). European Journal of Phycology, v. 48, n. 1, p. 1-11, FEB 1 2013. Web of Science Citations: 27.