Scientists have built a small dot-based microbial plant that produces hydrogen, instead of oxygen, when exposed to sunlight in the air.
The findings of the international research team are based on University of Bristol and the Harbin Institute of Technology in China, published today (November 25, 2020) Natural Communication,
Normally, algae cells fix carbon dioxide and produce oxygen by photosynthesis. Research uses sugar droplets packed with living algae cells to produce hydrogen, rather than oxygen, by photosynthesis.
Hydrogen has the potential to be a climate-neutral fuel, offering many possible uses as a future energy source. A major drawback is that hydrogen production involves the use of a lot of energy, so green alternatives are sought and these inventions can provide important steps.
The team, consisting of Professor Stephen Mann and Dr. Mei Li of Bristol’s School of Chemistry along with Professor Xin Huang and colleagues at the Harbin Institute of Technology in China, traps ten thousand or more algae cells in each droplet, which is then formed by osmotic compression by burying the cells inside the droplet, the oxygen level falls. to the level of a special enzyme called hydrogenase that hijacks the normal photosynthetic pathway to produce hydrogen. In this way, about a quarter of a million microbial plants, usually only a tenth of a millimeter, can be prepared in one milliliter of water.
To increase the rate of hydrogen evolution, the team coated the living micro-reactors with a thin bacterial shell, which can produce oxygen thus increasing the number of algae cells maintained for hydrogenase activity.
Although still in its infancy, the work provided a step towards the development of photobiological green energy under natural aerobic conditions.
Professor Stephen Mann, Co-Director of the Max Planck Bristol Center for Minimal Biology in Bristol, said: “Using simple droplets as vectors to control the organization of algae cells and photosynthesis in synthetic microchips offers a potentially seeded approach to hydrogen production that we hope to develop the future. “
Professor Xin Huang at the Harbin Institute of Technology adds: “Our methodology is simple and should be able to scale-up without compromising the viability of living cells. “
References: “Production of photosynthetic hydrogen by micro-reactants micro-reactors under aerobic conditions” by Xu Z, Wang S, Li S, Liu X, Wang L, Li M, Huang X and Mann S, November 25, 2020, Natural Communication,
DOI: 10.1038 / s41467-020-19823-5