The Establishment of a Marine Focused Biorefinery for Bioethanol Production Using Seawater and a Novel Marine Yeast Strain
by Abdelrahman Saleh Zaky, Darren Greetham, Gregory A. Tucker & Chenyu Du (Scientific Reports) Current technologies for bioethanol production rely on the use of freshwater for preparing the fermentation media and use yeasts of a terrestrial origin. Life cycle assessment has suggested that between 1,388 to 9,812 litres of freshwater are consumed for every litre of bioethanol produced. Hence, bioethanol is considered a product with a high-water footprint. This paper investigated the use of seawater-based media and a novel marine yeast strain ‘Saccharomyces cerevisiae AZ65’ to reduce the water footprint of bioethanol. Results revealed that S. cerevisiae AZ65 had a significantly higher osmotic tolerance when compared with the terrestrial reference strain. Using 15-L bioreactors, S. cerevisiae AZ65 produced 93.50 g/L ethanol with a yield of 83.33% (of the theoretical yield) and a maximum productivity of 2.49 g/L/h when using seawater-YPD media. This approach was successfully applied using an industrial fermentation substrate (sugarcane molasses). S. cerevisiae AZ65 produced 52.23 g/L ethanol using molasses media prepared in seawater with a yield of 73.80% (of the theoretical yield) and a maximum productivity of 1.43 g/L/h. These results demonstrated that seawater can substitute freshwater for bioethanol production without compromising production efficiency. Results also revealed that marine yeast is a potential candidate for use in the bioethanol industry especially when using seawater or high salt based fermentation media. READ MORE
Seawater could be used to lower freshwater footprint of bioethanol (Biofuels Interntional)
Less drain on freshwater supplies with seawater fuel discovery (University of Nottingham/Phys.Org)
Researchers use seawater to produce ethanol (Ethanol Producer Magazine)
Less drain on freshwater supplies with seawater fuel discovery (University of Nottingham)