Bioenergetic changes in the microalgal photosynthetic apparatus by extremely high CO2 concentrations induce an intense biomass production

TitleBioenergetic changes in the microalgal photosynthetic apparatus by extremely high CO2 concentrations induce an intense biomass production
Publication TypeJournal Article
Year of Publication2008
AuthorsPapazi, A, Makridis P, Divanach P, Kotzabasis K
JournalPhysiologia Plantarum
Volume132
Issue3
Pages338 - 349
Abstract

Unicellular green alga Chlorella minutissima, grown under extreme carbon dioxide concentrations (0.036-100%), natural temperature and light intensities (Mediterranean conditions), strongly increase the microalgal biomass through photochemical and non-photochemical changes in the photosynthetic apparatus. Especially, CO2 concentrations up to 10% enhance the density of active reaction centers (RC/CSo), decrease the antenna size per active reaction center (ABS/RC), decrease the dissipation energy (DI o/RC) and enhance the quantum yield of primary photochemistry (F v/Fm). Higher CO2 concentrations (20-25%) combine the above-mentioned photochemical changes with enhanced non-photochemical quenching of surplus energy, which leads to an enhanced steady-state fraction of 'open' (oxidized) PSII reaction centers (q p), and minimize the excitation pressure of PSII (1 - qp) under very high light intensities (approximately 1700 μmol m-2 s-1 maximal value), avoiding the photoinhibition and leading to an enormous biomass production (approximately 2500%). In conclusion, these extreme CO2 concentrations - about 1000 times higher than the ambient one - can be easily metabolized from the unicellular green alga to biomass and can be used, on a local scale at least, for the future development of microalgal photobioreactors for the mitigation of the factory-produced carbon dioxide. © Physiologia Plantarum 2007.

URLhttp://www.scopus.com/inward/record.url?eid=2-s2.0-38949180996&partnerID=40&md5=67ebe674e3a912ac5f7df3e8c78aa654

User login