Increased lipid synthesis in the culture of Chlorella homosphaera with magnetic fields application

Abstract

This study aimed to investigate the influence of different intensities (15, 30 and 60 mT) and exposure times (1 h d^-1_, 24 h d^-1) of magnetic fields (MF) on the stimulation of lipid synthesis by the microalga Chlorella homosphaera. The growth and biochemical characterization of protein, carbohydrate and lipid content were determined. Biomass concentration increased by 20.6% (30 mT, 1 h d^-1) and 12.4% (60 mT, 1 h d^-1) in the presence of MF. However, biomass decreased by 33.0% (15 mT, 1 h d^-1) in relation to control cultivation (CC). The stress caused by the MF application stimulated lipid synthesis and biomass production. In all evaluated conditions, MF application showed a positive effect on lipid production; the application of 60 mT or 30 mT for 1 h d^-1 increased lipid productivity by 108.4% and 135.1%, respectively. MF application with ferrite magnets was thus efficient to stimulate lipid synthesis.

Keywords: Biodiesel; Chlorophyte; Lipid accumulation; Microalgae.