Optimization of Medium Using Response Surface Methodology for Lipid Production by Scenedesmus sp.

Abstract

Lipid production is an important indicator for assessing microalgal species for biodiesel production. In this work, the effects of medium composition on lipid production by Scenedesmus sp. were investigated using the response surface methodology. The results of a Plackett–Burman design experiment revealed that NaHCO3, NaH2PO4·2H2O and NaNO3 were three factors significantly influencing lipid production, which were further optimized by a Box–Behnken design. The optimal medium was found to contain 3.07 g L−1 NaHCO3, 15.49 mg L−1 NaH2PO4·2H2O and 803.21 mg L−1 NaNO3. Using the optimal conditions previously determined, the lipid production (304.02 mg·L−1) increased 54.64% more than that using the initial medium, which agreed well with the predicted value 309.50 mg L−1. Additionally, lipid analysis found that palmitic acid (C16:0) and oleic acid (C18:1) dominantly constituted the algal fatty acids (about 60% of the total fatty acids) and a much higher content of neutral lipid accounted for 82.32% of total lipids, which strongly proved that Scenedesmus sp. is a very promising feedstock for biodiesel production.

The influence of cultivation period on growth and biodiesel properties of microalga Nannochloropsis gaditana 1049

“…To investigate the induction of lipid, carbohydrates and protein synthesis characteristics changing with the cultivation period, the microalgal cells cultivated in the tubes were designed to harvest since day 7. At the same time, dry cell weight (DCW) was measured in the harvested columns to estimate the influence of cultivation period on biomass accumulation (Yang et al, 2014;Ma et al, 2014). Each designed harvesting experiment was performed in three replicates, and then harvested by centrifugation (5000g  5 min) and freeze-dried the wet algal pellet immediately, the dry biomass was analyzed immediately or stored at À20°C for up to 10-days prior to analysis.…”

“…The analysis parameters and programs of GC-MS previously reported by Yang et al (2014) were adopted. The content of each FAs component was determined by the area normalization method, and peak areas were quantified with Chrom-card for Windows software.…”

A comparative analysis of fatty acid composition and fucoxanthin content in six Phaeodactylum tricornutum strains from diff erent origins

“…Intracellular total lipid was extracted and determined as previously described (Yang et al, 2014a). Total lipid content (% of dried cell wt) was calculated according to lipid weight and biomass.…”

Environmental Factors Influencing Algal Biodiesel Production

“…Nitrogen is a key constituent of all structural and functional proteins within the algal cells and accounts for 7% to 20% of cell DW (Richmond, 2008). Foremost effects of nitrogen deficiency in algal culture consist of the enhanced biosynthesis and accumulation of lipids (Muradyan et al, 2004;Demirbas, 2010;Surendhiran and Vijay, 2014) and triglycerides (Takagi et al, 2000;Stephenson et al, 2010;Yang et al, 2014) with a concurrent decrease in protein content. Biomass concentration and lipid productivity was reached at highest level with a nitrogen concentration; it was raised ten times that of the standard medium in D. tertiolecta (Mata et al, 2013).…”