Ammonium Nutrition Induces Triacylglycerol, ?-carotene, and Lutein Production in Dunaliella tertiolecta Butcher

Abstract

Distinct impacts of ammonium nutrition for simultaneous production of triacylglycerol, lutein, and beta-carotene were evaluated in Dunaliella tertiolecta. A physiologically realistic growth system was employed to compare metabolite production and growth characteristics of nitrogen deprived, ammonium- and nitrate supplied a tertiolecta. The nitrogen dependent changes in D. tertiolecta were reflected as a dramatic decrease in growth related to decreased photosynthetic activity, reduced pigmentation and increased triacylglycerol production as observed in nitrogen deprived microalgae. On the other hand, ammonium nutrition caused a time-dependent increase of neutral lipids, triacylglycerols, chlorophylls and carotenoids, lutein and beta-carotene in particular. Finally, ammonium nutrition improved FAME profile of D. tertiolecta for biodiesel production via an exclusive impact on increased saturation.