New Approach Derives Hydrogen from Algae

by Elizabeth Montalbano (Design News) Researchers at the University of Turku in Finland have discovered a novel way to develop biofuel from green algae. -- ...One of the most promising alternatives has been molecular hydrogen, which provides carbon-free power in one of the cleanest ways possible. Now, researchers at the University of Turku in Finland have found an approach to turning solar energy into bio-hydrogen through the photosynthesis of green algae. In doing so, they may enable the efficient production of biofuel.

Green algae can be a good biocatalyst for producing hydrogen for energy production. It can transform solar energy and carbon dioxide directly into different valuable compounds, such as vitamins, antioxidants, polymers, and carbohydrates, researchers have found.

Now, however, the Turku team believes it has found an answer in a new method for producing hydrogen that does not expose green algae to additional nutritional starvation, researchers said. This, in turn, does not apply significant stress to the cells.

“We showed that the hydrogen photo-production activity could be sustained by simply exposing the anaerobic algal cultures to a train of strong but short light pulses interrupted by longer dark phases,” Allahverdiyeva-Rinne said.“Under such conditions, green algae do not accumulate oxygen and switch photosynthesis toward hydrogen production instead of biomass. The process lasts for at least several days.”

The team’s research also revealed another obstacle to efficient hydrogen production: a strong competition between two metabolic pathways. Specifically, the issues are carbon dioxide fixation leading to the biomass accumulation and the hydrogenase enzyme-catalyzing photo-production of hydrogen, researchers said.

The biofuel produced by the team is molecular hydrogen gas, which is “considered as one of the most promising energy-carrier alternatives to the fossil fuels, due to its highest energy content and the zero-carbon release index,” Allahverdiyeva-Rinne (Yagut Allahverdiyeva-Rinne, associate professor of molecular plant biology at the University of Turku) said. READ MORE