udy Siegel-Itzkovich writes in the Jerusalem Post that Dr. Iftach Yacoby and his research team at Tel Aviv University, in Israel, have genetically altered microalgae to increase its efficiency of producing hydrogen to five times its natural ability.
“Hydrogen is an energy source with huge advantages,” says Dr. Yacoby. “First, it has a tremendous energy content. The travel range of a hydrogen-powered car is more than 500 kilometers per five kilos of hydrogen, and an electric bicycle over 100 kilometers per 30 grams of the bicycle fuel. Secondly, hydrogen does not pollute at all. The process of using an electric fuel cell generates only water vapor, and exhaust emitted by a hydrogen-powered car contains only clean water that can even be suitable for drinking.”
“Hydrogen is produced by algae with the help of an enzyme called hydrogenase that breaks down in the presence of oxygen,” he says. “At night, no oxygen is produced, and when the amount of oxygen decreases, the cell creates a large amount of hydrogenase. The assumption so far has been that for a few moments around sunrise, with exposure to sunlight, the algae produce both hydrogen and oxygen. But very quickly, the oxygen accumulates and paralyzes the hydrogenase, and hydrogen production stops. We decided to test this assumption.”
To their surprise, the researchers found that even in the daylight, when the photosynthesis process occurs, the algae produce large amounts of oxygen and also emit a tiny amount of hydrogen. From this, they concluded that in the algae are areas with no oxygen that make it possible for hydrogenase to function.
“Later we found in the algae three effective mechanisms that work tirelessly to remove the oxygen from the cell, allowing hydrogenase to produce hydrogen continuously throughout the daylight hours,” Dr. Yacoby said. “This makes it clear that algae have a huge underutilized potential for the production of hydrogen fuel.”
In the next stage, the researchers used genetic engineering to intervene in the photosynthesis of microalgae. Their aim was to cause the cell to produce a greater amount of hydrogenase at the expense of other processes, such as production of sugar, thereby increasing the production of hydrogen. In this way, they were able to engineer laboratory microalgae to produce 400% more than the original microalgae.