N. Rossignol et al., Production of exocellular pigment by the marine diatom Haslea ostrearia Simonsen in a photobioreactor equipped with immersed ultrafiltration membranes, BIORES TECH, 73(2), 2000, pp. 197-200
A new photobioreactor coupled with an ultrafiltration system (immersed memb
ranes) was investigated for the continuous culture of the microalga Haslea
ostrearia in order to improve pigment (marennine) production and recovery.
The system presents a commercial interest, because energetic costs were min
imized, and the cells were not submitted to any shear stress due to pumping
or circulation. To obtain this, since the photobioreactor was of cylindric
al type, a membrane module was placed at the bottom of the reactor and the
hydrostatic pressure (the height of the water column) used as driving force
both for the permeation and periodical backflushing steps. The production
of biomass and marennine was stable for a three-week period, with marennine
specific productivity approximate to 30-35 mg 10(-9) cell day(-1), marenni
ne concentration approximate to 3 times higher than in a conventional batch
photobioreactor. The permeation Aux obtained was acceptable (3-10 l h(-1)
m(-2), 3 kPa, 15 degrees C), but for such applications, this type of integr
ated process needs further improvements. Owing to its simple design, the co
ncept "photobioreactor - ultrafiltration with immersed membranes" has good
possibilities in biotechnology and aquaculture for continuous extraction of
exocellular metabolites. (C) 2000 Elsevier Science Ltd. All rights reserve
d.