title: Coordinated regulation of nitrogen supply mode and initial cell density for energy storage compounds production with economized nitrogen utilization in a marine microalga Isochrysis zhangjiangensis.
abstract: Lipids and carbohydrates are main energy storage compounds (ESC) of microalgae under stressed conditions and they are potential feedstock for biofuel production. Yet, the sustainable and commercially successful production of ESC in microalgae needs to consider nitrogen utilization efficiency. Here the impact of different initial cell densities (ICDs) on ESC accumulation in Isochrysis zhangjiangensis under two nitrogen supply modes (an initially equal concentration of nitrogen per-cell in the medium (N1) and an equal total concentration of nitrogen in the culture system (N2)) were investigated. The results demonstrated that the highest ESC yield (1.36gL(-1)) at N1, which included a maximal nitrogen supply in the cultivation system, and the highest ESC content (66.5%) and ESC productivity per mass of nitrogen (3.28gg(-1) (N) day(-1)) at N2, were all obtained under a high ICD of 8.0×10(6)cellsmL(-1). Therefore I. zhangjiangensis qualifies for ESC-enriched biomass production with economized nitrogen utilization.
authors.affiliation: Marine Bioengineering Group, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China; University of Chinese Academy of Sciences, Beijing 100039, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Chi
authors.affiliation: Marine Bioengineering Group, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
authors.forename: Changhong
authors.initials: C
authors.lastname: Yao
authors.affiliation: Marine Bioengineering Group, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
authors.forename: Xupeng
authors.initials: X
authors.lastname: Cao
authors.affiliation: Marine Bioengineering Group, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China. Electronic address: xuesong@dicp.ac.cn.
authors.forename: Song
authors.initials: S
authors.lastname: Xue
mesh_terms: D056804:Biofuels; D018533:Biomass; D002241:Carbohydrates / Q000737:chemistry*; D058087:Haptophyta / Q000166:cytology*; D008055:Lipids / Q000096:biosynthesis*; D058086:Microalgae / Q000166:cytology*; D009566:Nitrates / Q000737:chemistry; D009584:Nitrogen / Q000737:chemistry*; D010078:Oxazines / Q000737:chemistry; D045332:Photosystem II Protein Complex
chemical_list: D056804:Biofuels; D002241:Carbohydrates; D008055:Lipids; D009566:Nitrates; D010078:Oxazines; D045332:Photosystem II Protein Complex; D009584:Nitrogen; C044808:nile red
keywords: Energy storage compounds; Initial cell density; Isochrysis zhangjiangensis; Nitrogen; Nitrogen utilization efficiency