Mechanism behind autoflocculation of unicellular green microalgae Ettlia texensis.
The oleaginous Ettlia texensis is an autoflocculating green microalga that can be used for bio-flocculation of other microalgae species to facilitate harvesting. In this study the mechanism behind autoflocculation of E. texensis was revealed by scanning electron microscopy (SEM) analysis and by characterisation of the cell surface properties. SEM analysis and measurement of extracellular polymeric substances (EPS) showed that autoflocculation of E. texensis is due to the EPS containing mainly glycoproteins patched to the cell surface. Despite the presence of charged groups on the cell surface, they do not seem to attribute to autoflocculation of E. texensis. During bio-flocculation of E. texensis with Chlorella vulgaris EPS structures between both microalgal species were observed. EPS thus not only play a predominant role in autoflocculation of E. texensis but also in bio-flocculation when using this microalga to harvest others.
Bioprocess Engineering, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands. Electronic address: sina.salim@gmail.com.
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S
Salim
Bioprocess Engineering, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands.
N R
NR
Kosterink
Bioprocess Engineering, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands.
N D
ND
Tchetkoua Wacka
Bioprocess Engineering, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands.
M H
MH
Vermuë
Bioprocess Engineering, Wageningen University, P.O. Box 8129, 6700 EV Wageningen, The Netherlands.
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RH
Wijffels
D018533:Biomass; D001704:Biopolymers / Q000378:metabolism; D019149:Bioreactors; D000460:Chlorophyta / Q000145:classification / Q000502:physiology* / Q000648:ultrastructure; D005427:Flocculation; D006023:Glycoproteins / Q000378:metabolism*; D058086:Microalgae / Q000502:physiology* / Q000648:ultrastructure; D008855:Microscopy, Electron, Scanning
D001704:Biopolymers; D006023:Glycoproteins
Autoflocculation; Ettlia texensis; Harvesting; Microalgae