Scientists of Cologne University have developed a more cost-efficient
method to cultivate algae, which could lead to an increase in the use
of microalgae in a wide range of applications - from food production to
medical applications and nutrient recovery. This new technological method, developed by algae specialist
Professor Michael Melkonian and his team, could make the production of
algae easier - and hence reduce the costs of the products based on this
material. Many years of research work on the development of photobioreactors,
which use photosynthesis to turn light energy into biomass, have
preceded this success. The so called "Porous Substrate Bioreactor" (PSBR), also known as the
twin-layer system, uses a new principle to separate the algae from a
nutrient solution by means of a porous reactor surface on which the
microalgae are trapped in biofilms. Special about this new procedure is that it reduces the amount of
liquid needed in comparison to the currently used technology, which
cultivates algae in suspensions, by a factor of up to one hundred. The
PSBR procedure thus allows for a significant reduction in energy and for
an increase in the portfolio of algae that can be cultivated. Current successes in PSBR development and the rise in interest in
this technology in recent years could signal a turn in the conception of
future photobioreactors in microalgae biotechnology. Microalgae have numerous applications: they are traditional sources
of protein and carbohydrates. They can also be used in the sustainable
production of natural pigments and antioxidants such as beta-carotene
and astaxanthin. Polyunsaturated fatty acids, which usually come from
fish oil, can also be synthesized from microalgae. Furthermore, algae can serve as the basis for pharmaceutical agents
such as antiviral and anticancerogenous substances. In environmental
biotechnology, new concepts are currently being developed to employ
microalgae to recover phosphor and nitrogen from sewage and reintroduce
them into the nutrient cycle by means of organic fertilizers.
These findings are published in the journal Trends in Biotechnology.
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