Relatively higher quantity of fermentable sugars of galactose and glucose can be obtained by acid-hydrolisis of red algae [30.4% of dry matter on average (10)], and both of the sugars can be further metabolized to ethanol by yeast with a conversion efficiency at 51% (w/w) according to the following reaction: C6H12O6→2C2H5OH + 2CO2. Park et al. (11) and Yanagisawa et al.