title: Polyphosphate during the Regreening of Chlorella vulgaris under Nitrogen Deficiency.
abstract: Polyphosphate (Poly-P) accumulation has been reported in Chlorella vulgaris under nitrogen deficiency conditions with sufficient P supply, and the process has been demonstrated to have great impact on lipid productivity. In this article, the utilization of polyphosphates and the regreening process under N resupplying conditions, especially for lipid production reviving, were investigated. This regreening process was completed within approximately 3-5 days. Polyphosphates were first degraded within 3 days in the regreening process, with and without an external P supply, and the degradation preceded the assimilation of phosphate in the media with an external P offering. Nitrate assimilation was markedly influenced by the starvation of P after polyphosphates were exhausted in the medium without external phosphates, and then the reviving process of biomass and lipid production was strictly impeded. It is, thus, reasonable to assume that simultaneous provision of external N and P is essential for overall biodiesel production revival during the regreening process.
authors.affiliation: Advanced Laboratory for Environmental Research and Technology, USTC-CityU, Suzhou 215123, China. chuffei@mail.ustc.edu.cn.|College of Standardization, China Jiliang University, Hangzhou 310018, China. chuffei@mail.ustc.edu.cn.
authors.forename: Fei-Fei
authors.initials: FF
authors.lastname: Chu
authors.affiliation: Advanced Laboratory for Environmental Research and Technology, USTC-CityU, Suzhou 215123, China. sxf0912@mail.ustc.edu.cn.
authors.forename: Xiao-Fei
authors.initials: XF
authors.lastname: Shen
authors.affiliation: Advanced Laboratory for Environmental Research and Technology, USTC-CityU, Suzhou 215123, China. bhpksl@cityu.edu.hk.|State Key Laboratory in Marine Pollution, Department of Biology and Chemistry, City University of Hong Kong, Kowloon 999077, Hong Kong. bhpksl@cityu.edu.hk.
authors.forename: Paul K S
authors.initials: PK
authors.lastname: Lam
authors.affiliation: Advanced Laboratory for Environmental Research and Technology, USTC-CityU, Suzhou 215123, China. rzeng@ustc.edu.cn.|CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei 230026, China. rzeng@ustc.edu.cn.
authors.forename: Raymond J
authors.initials: RJ
authors.lastname: Zeng
mesh_terms: D018533:Biomass; D048408:Chlorella vulgaris / Q000187:drug effects / Q000378:metabolism*; D002734:Chlorophyll / Q000378:metabolism; D000077194:Chlorophyll A; D004952:Esters / Q000378:metabolism; D066292:Lipid Droplets / Q000187:drug effects / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D009584:Nitrogen / Q000172:deficiency*; D011122:Polyphosphates / Q000494:pharmacology*
chemical_list: D004952:Esters; D011122:Polyphosphates; D002734:Chlorophyll; D009584:Nitrogen; D000077194:Chlorophyll A
keywords: Chlorella vulgaris; biodiesel production; nitrogen deficiency; phosphate supply; polyphosphates; regreening