Physiological and technological considerations for optimising mass algal cultures
J.U. Grobbelaar-2000
Journal of Applied Phycology, 12 (3-5) : 201-206
(from Current Contents)
Abstract:
The successful coupling between physiology and
technology is central to the success of algal biotechnology. Imperative is a
proper understanding of the variables and their impacts on biomass and/or
biocompound production. The crux lies in photosynthesis and the capturing of
light energy at the optimal rate for eventual maximal photochemistry
(biosynthesis). It is in the hands of algal biotechnologists to understand
the dynamics and regulatory mechanisms of especially PSII (photosystem II)
activity in order to advance this technology further. Biophysical and
technological optimisation and design aimed at maximising photon flux
capture are some of the avenues that needs be pursued. This needs to be
augmented by molecular, biochemical and physiological inputs. Unfortunately
detailed systematic analyses of the variables, their interaction and
possible synergism have rarely been done. The debate regarding the merits
and productivity in closed, either plate or tubular, vertical or horizontal,
and open pond reactors need to be resolved. Exciting developments regarding
online measurements and feedback control for optimal productivities are part
of the solutions and approaches that need to be followed. Multistage systems
that not only utilise autotrophic growth and stress components, but also
combined autotrophic/heterotrophic systems could provide solutions to
specific production requirements. These and other important issues are
addressed in the overview. The challenges facing algal biotechnologists and
future research needs are also discussed.
(Univ Orange Free
State, ZA-9300 Bloemfontein, South Africa, e-mail: grobbelj@plk.nw.uovs.ac.za)