The most abundant sugars in brown algae are alginate, mannitol and laminarin.
Mannitol and glucose from laminarin (a form of glucan in brown algae) are normal sugars that are efficiently used for bioethanol fermentation.
Laminarin and mannitol from Laminaria hyperborea extracts were fermented to bioethanol under oxygen-limiting conditions using Zymobacter palmae.
Bioethanol with a yield of 0.4 g ethanol/g of sugars was produced with ethanogenic Escherichia coli KO11 from Laminaria japonica hydrolysates mainly containing mannitol after chemo-enzymatic saccharification.
Ethanol of 7.7 g/L was produced from S. japonica biomass using the simultaneous saccharification and fermentation (SSF) method with a theoretical yield of 33.3%.