title: Changes of Photosynthetic Behaviors and Photoprotection during Cell Transformation and Astaxanthin Accumulation in Haematococcus pluvialis Grown Outdoors in Tubular Photobioreactors.
abstract: The cell transformation from green motile cells to non-motile cells and astaxanthin accumulation can be induced in the green algaHaematococcus pluvialiscultured outdoors. In the initial 3 d of incubation (cell transformation phase), light absorption and photosynthetic electron transport became more efficient. After five days of incubation (astaxanthin accumulation phase), the light absorption per active reaction center (ABS/RC) increased, but the efficiency of electron transport (ψo) and the quantum yield of electron transport (φEo) decreased with increased time, indicating that the capacity of photosynthetic energy utilization decreased significantly during astaxanthin accumulation, leading to an imbalance between photosynthetic light absorption and energy utilization. It would inevitably aggravate photoinhibition under high light, e.g., at midday. However, the level of photoinhibition inH. pluvialisdecreased as the incubation time increased, which is reflected by the fact thatFv/Fmdetermined at midday decreased significantly in the initial 3 d of incubation, but was affected very little after seven days of incubation, compared with that determined at predawn. This might be because the non-photochemical quenching, plastid terminal oxidase, photosystem I cyclic electron transport, defensive enzymes and the accumulated astaxanthin can protect cells against photoinhibition.
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China. zhanglitao666@163.com.|National-Local Joint Engineering Research Center for Haematococcus pluvialis and Astaxanthin, Yunnan Alphy Biotech Co., Ltd., Chuxiong 675012, China. zhanglitao666@163.com.|Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China. zhanglitao666@163.com.
authors.forename: Litao
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China. sufang116@126.com.|Institute of Oceanology, University of Chinese Academy of Sciences, Beijing 100049, China. sufang116@126.com.
authors.forename: Fang
authors.initials: F
authors.lastname: Su
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China. zhangchunhui13@mails.ucas.ac.cn.|Institute of Oceanology, University of Chinese Academy of Sciences, Beijing 100049, China. zhangchunhui13@mails.ucas.ac.cn.
authors.forename: Chunhui
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China. 18766216016@163.com.|Institute of Oceanology, University of Chinese Academy of Sciences, Beijing 100049, China. 18766216016@163.com.
authors.forename: Fengying
authors.initials: F
authors.lastname: Gong
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China. jgliu@qdio.ac.cn.|National-Local Joint Engineering Research Center for Haematococcus pluvialis and Astaxanthin, Yunnan Alphy Biotech Co., Ltd., Chuxiong 675012, China. jgliu@qdio.ac.cn.|Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China. jgliu@qdio.ac.cn.
authors.forename: Jianguo
authors.initials: J
authors.lastname: Liu
mesh_terms: D019149:Bioreactors; D002465:Cell Movement; D000460:Chlorophyta / Q000254:growth & development / Q000378:metabolism* / Q000502:physiology; D004579:Electron Transport; D010788:Photosynthesis; D024341:Xanthophylls / Q000096:biosynthesis
chemical_list: D024341:Xanthophylls; C005948:astaxanthine
keywords: Haematococcus pluvialis; astaxanthin; chlorophyll a fluorescence transient; photoinhibtion; photosynthetic behavior