Effects of nitrogen sources on cell growth and lipid accumulation of green alga Neochloris oleoabundans

Abstract

Microalgal lipids are the oils of future for sustainable biodiesel production. However, relatively high production costs due to low lipid productivity have been one of the major obstacles impeding their commercial production. We studied the effects of nitrogen sources and their concentrations on cell growth and lipid accumulation of Neochloris oleoabundans, one of the most promising oil-rich microalgal species. While the highest lipid cell content of 0.40 g/g was obtained at the lowest sodium nitrate concentration (3 mM), a remarkable lipid productivity of 0.133 g l(-1) day(-1) was achieved at 5 mM with a lipid cell content of 0.34 g/g and a biomass productivity of 0.40 g l(-1) day(-1). The highest biomass productivity was obtained at 10 mM sodium nitrate, with a biomass concentration of 3.2 g/l and a biomass productivity of 0.63 g l(-1) day(-1). It was observed that cell growth continued after the exhaustion of external nitrogen pool, hypothetically supported by the consumption of intracellular nitrogen pools such as chlorophyll molecules. The relationship among nitrate depletion, cell growth, lipid cell content, and cell chlorophyll content are discussed.

Optimization of Process Parameters for CO2 Fixation from Bicarbonate Source by a Microalgae

“…Chlorophyll is an essential component of photosynthesis in green microalgae that captures light energy and CO 2 for metabolic activity for cell growth and lipid accumulation (Li et al, 2008). The interaction effect between the variables (pH, ammonium bicarbonate and inoculum size) on chlorophyll content of microalgae has been shown in the Fig.…”

“…The decrease in chlorophyll content could be due to the adaptation of microalgae in the medium. At later stage, chlorophyll starts increasing which may be due to the fact that when large source of nitrogen compound is available, the cells will produce large chlorophyll content (Li et al, 2008).…”

Effects of Sodium Nitrate and Mixotrophic Culture on Biomass and Lipid Production in Hypersaline Microalgae Dunaliella Viridis Teod

“…In the past decade, bioenergy production from microalgae has been the subject of many studies. A few microalgae species including some Chlorella, Dunaliella, Nannochloris, Neochloris and Botryococcus have the capacity for accumulating large quantities of lipids in their cells under favorable conditions (Li et al 2008). Biofuel production from microalgae is dependent on the rate of microalgae biomass production and their lipid content (Chen et al 2011).…”

“…D. salina and D. viridis are the predominant phytoplankton species in lakes with intermediate to high salinity levels (Davis 1990). To reduce the load on freshwater sources, microalgal species that can grow and reproduce in environments with moderate to high salinity seems to be good choice for biofuel production (Li et al 2008). D. viridis, due to its high growth rate and its unique advantage of growth in coastal regions using sea water have been considered for biofuel production.…”

Generation of bioethanol from common date by-products, Teggaza and Lebghel in Southern Algeria

“…The production of bioethanol from lignocellulose raw materials requires generally the incorporation of an efficient pretreatment, followed by a scarification of the carbohydrates to obtain satisfactory effectiveness (Acourene and Ammouche, 2012). Compared to the use of gasoline, bioethanol helps to reduce CO 2 emission to about 80% (Li et al, 2008).…”