Study of the hydrodynamic effect in column PBR on cellular growth, nitrogen removal, lipid productivity and fatty acid profile in Chlorella vulgaris.

Abstract

In this work we analyzed different biochemical parameters such as cell growth, nitrogen removal, lipid productivity and fatty acid profile in Chlorella vulgaris by hydrodynamic effect varying the aeration to (0.75, 1.25, 1.75, 2.25) vvm and white light conditions continuous in column photobioreactor; hydrodynamic calculations of the FBR were carried out to determine the shear rate and possible existence of hydrodynamic stress at the proposed aeration conditions; the values reached in the shear rate were reduced (0.0025 to 0.0220) s-1, observing flow of homogeneous type in all the experiments; however, the maximum values of cell growth and specific growth rate (μ) were (5.90x106 cells mL-1 and 0.0229 d-1) respectively, as well as the highest N consumption (60%) and the highest productivity of lipids (8.98 mgL-1d-1) were reached during the experiment at 0.75 vvm. In relation to the analysis of the fatty acid profile greater presence of polyunsaturated fatty acids (PUFA) was observed in the experiments at 0.75 vvm, 1.75 vvm and 2.25 vvm, however, at 1.25 vvm, higher productivity of saturated fatty acids (SFA) was obtained; with respect to monounsaturated fatty acids (MUFA) the highest concentration was reflected at 0.75 vvm. The components with the highest presence in the fatty acid profile analysis were C12: 0; C20: 5N3; C24: 1; C 22: 0; C22: 2.