Effect of phosphorus on biodiesel production from Scenedesmus obliquus under nitrogen-deficiency stress

Impacts of nitrogen and phosphorus starvation on the physiology of Chlamydomonas reinhardtii

“…The neutral lipid per cell of all the nutrient-starved groups were higher; this is consistent with most of the nutrient limitation studies carried out to date (Tornabene et al 1983;ElSheek and Rady 1995;Kilham et al 1997;Zhila et al 2005;Li et al 2008;Converti et al 2009;Stephenson et al 2010;Yeh and Chang 2011;Uslu et al 2011;Ördög et al 2011;Praveenkumar et al 2012;Zhang et al 2013;Ito et al 2013;Chu et al 2014). Except for the last day of the study, all the nutrient-limited treatments had similar cellular neutral lipid content.…”

“…Most of the published reports focusing on the manipulation of nutrient limitation to obtain high lipid production have focused on either nitrogen or phosphorus limitation alone, and have not considered the combined effects of applying both N and P limitation together (Terry et al 1985;Kilham et al 1997;Praveenkumar et al 2012;Chu et al 2014). Although Liebig's law of the minimum suggests that only one (the most limiting) nutrient will be growth-limiting at any one time (Browne 1942), recent work suggests that co-limitation by two or more nutrients occurs naturally, especially between nitrogen and phosphorus (Elser et al 2007;Harpole et al 2011).…”

Enhancement of FAME productivity of Scenedesmus obliquus by combining nitrogen deficiency with sufficient phosphorus supply in heterotrophic cultivation

“…In particular, the lack of phosphorus caused an obvious decline of biomass growth and FAME content under nitrogen starvation stress. These results indicate that phosphorus plays a positive role in heterotrophic oil production of S. obliquus, especially under N deprivation condition, which is consistent with our previous study in autotrophic cultures [21]. At present, the functional mechanism of P in lipid metabolism is mostly discussed under autotrophic conditions and the Table 4 Variations of fatty acid yield (COD Fatty Acid /COD Acetate ) during 6-day cultivation.…”

“…In addition, it was observed that the growth rates of NÀ&P and NÀ&P-lim were very close to N&P and N&P-lim. These data showed that removal of nitrogen did not cause a sharp decrease of the growth rate in heterotrophic cultures with acetate, which was different from the autotrophic system [14,15,21]. Fig.…”

“…The highest biodiesel productivity (24.2 mg L À1 d À1 ) was achieved by combing nitrogen deficiency and sufficient phosphorus supply. It showed that nitrogen starvation associated with sufficient phosphorus could greatly enhance lipid productivity in S. obliquus [21]. However, it is uncertain whether the effects of nitrogen and phosphorus on S. obliquus in heterotrophic culture are similar to those in autotrophic culture.…”