11–16%. As shown in Fig. 2, an ethanol volume percentage of 5.8%
(v/v), corresponding to ethanol weight percentage of 4.58% (w/v),
was obtained from 12.3% reducing sugars in G. corneum hydrolysates
after 96 h of fermentation. Finally, over 20% (w/w) ethanol
from the dissolved carbohydrates in the extracts was obtained. Enzyme
saccharification of galactan, the main components of the extracts,
may help reduce the formation of fermentation inhibitors
such as furans and HMF, and may help increase ethanol yield
and simplify the saccharification process. Further study in this area
is necessary.
In this process, red algae pulp was produced simultaneously at
10–11% yield by algal dry weight with superior physical properties
over the wood chemical pulp (Seo et al., 2010). Market price of
wood chemical pulp is usually much higher than that of ethanol,
and it is expected that the price of red algae pulp would be higher
than that of wood chemical pulp, if commercialized. Simultaneous
production of pulp and ethanol from red algae instead of ethanol
alone (Park et al., 2012) may improve the economics of the process
and preserve forests.