Neochloris oleabundans UTEX #1185: a suitable renewable lipid source for biofuel production

Abstract

Energy crises, global warming, and climatic changes call for technological and commercial advances in manufacturing high-quality transportation fuels from unconventional feedstocks. Microalgae is one of the most promising sources of biofuels due to the high yields attained per unit area and because it does not displace food crops. Neochloris oleabundans (Neo) microalga is an important promising microbial source of single-cell oil (SCO). Different experimental growth and lipid production conditions were evaluated and compared by using optical density (540 nm), dry-weight determination, and flow cytometry (FC). Best Neo average biomass productivity was obtained at 30 degrees C under conditions of nitrogen-sufficiency and CO(2) supplementation (N+/30 degrees C/CO(2)), with an average doubling time of 1.4 days. The second and third highest productivities occurred with N-sufficient cultures without CO(2) supplementation at 26 degrees C (N+/26 degrees C) and at 30 degrees C (N+/30 degrees C), with doubling times of 1.7 and 2.2 days, respectively. Microbial lipid production was monitored by flow cytometry using Nile red (NR), a lipophilic fluorochrome that possesses several advantageous characteristics for in situ screening near real time (at line). Results showed maximum lipid content (56%) after 6 days of nitrogen depletion under nitrogen starvation without CO(2) supplementation (N-/30 degrees C), followed by N-/30 degrees C/CO(2) and N-/26 degrees C conditions with 52% lipid content, after 5 and 6 days of N starvation, respectively. The adequate fatty acid profile and iodine value of Neo lipids reinforced this microalga as a good source of SCO, in particular for use as biodiesel.

Evaluation of Diverse Microalgal Species as Potential Biofuel Feedstocks Grown Using Municipal Wastewater

“…The N. conjuncta grown in Bristol medium was found to have a lipid content (1.07 +/− 0.4 g lipid/g dry biomass) significantly (p = 0.0004) higher than any other species/medium combination, which ranged from 0.5 to 50 g lipid/g dry biomass. These values agree with the 0.27 (Sun et al, 2014), 0.50 (Griffiths et al, 2012), and 0.52 (Gouveia et al, 2009) g lipid/g dry biomass reported for N. oleoabundans.…”

Selection of microalgae for biodiesel production in a scalable outdoor photobioreactor in north China

“…The accuracy of these empirical equations in estimating the quality of biodiesel has been previously shown (Ramos et al, 2009;Hoekman et al, 2012). Moreover, measured values and calculated values by these equations in green algae C. protothecoides (Xu et al, 2006), Neochloris oleabundans (Gouveia et al, 2009) and S. obliquus (Abd El Baky et al, 2012) were compared prior to this study, and results indicated that the values from equations of Song et al (2014) were very close to the measured values. Thus, the biodiesel property in this study, the degree of unsaturation (DU), kinematic viscosity (KS), specific gravity (SG), cloud point (CP), iodine value (IV), cetane number (CN) and higher heating value (HHV) were determined by empirical equations from FA composition as described by Song et al (2014), while cold filter plugging point (CFPP) by Nascimento et al (2013).…”

Effect of salinity on the biochemical composition of the alga Botryococcus braunii Kütz IPPAS H-252

“…Moreover, lipid content, fatty acid profile, and acid value are also important parameters of biofuel (Gouveia et al 2009). It is known that lipid production by microalgae is regulated by environmental factors (Harwood and Jones 1989).…”