METHOD FOR INCREASING THE POTENTIAL FOR BIOFUEL PRODUCTION FROM MICROALGAE BY USING BIO-MODULATORS

摘要

The present invention proposes a method for cultivating and processing microalgae isolated from marine and extremophilic environments for optimal biofuel production. The species of microalgae selected can be species of the genus Dunaliella (D. bardawil, D. salina, D. acidophilo, D. biolecta, D. lateralis, D. maritima, D. minuta, D. parva, D. peircei, D. polymorpha, D. primolecta, D. pseudosalina, D. quartolecta, D. tertiolecta, D. viridis and others). For the purpose of cultivating microalgae for the production of biofuel, the optimal conditions for the production of biomass and lipids are different. This invention proposes a method which makes it possible to simultaneously stimulate the accumulation of biomass and intracellular lipids (more than 60% by dry weight), essentially the neutral lipids sought for the production of biodiesel, by reinforcing the action of natural bio-modulators or chemical analogues (auxins, cytoquinines, gibberellins, NaCI) in hypersaline and alkaline conditions. Another aspect of the invention is the application of ad hoc changes to the pH of the cultivation media causing the spontaneous precipitation of cells loaded with lipids once the cycle of growth and storage of lipids intended for the production of biodiesel is complete. This method makes it possible to recover microalgal biomass quickly and passively, requiring little energy and without the step of centrifugation or filtration, in order to extract the intracellular lipids and transform same into biodiesel. This method ensures very selective cultivation conditions which only a predetermined number of species has a similar response to and/or is able to tolerate, which limits the risks of contamination by other microalgae, bacteria or fungi, this frequently being a problem in open cultivation systems such as ponds. This offers a system for cultivating microalgae that is advantageous and applicable on a large scale for the biofuel application and others.