Bioethanol Production from Seaweed Kappaphycus alvarezii by Simultaneous Saccharification and Fermentation

摘要

Thermal acid hydrolysis pretreatment of Kappaphycus alvarezii was carried out with 12% (w/v) seaweed slurry and 180 mM H2SO4 at 140°C for 5 min. Utility of the thermotolerant yeast Kluyveromyces marxianus KCTC7150 was evaluated with respect to cell growth and ethanol fermentation at 40°C was close to optimal for enzymatic hydrolysis. This could lead to the integration of both the saccharification and fermentation processes. The levels of ethanol production by simultaneous saccharification and fermentation (SSF) with non-adapted and adapted K. marxianus KCTC7150 were 9.1 g/1 with an ethanol yield (Yeioh) of 0.24 and 10.2 g/1 with an ethanol yield (Yeioh) of 0.27 at 156 h, respectively. The two-phase SSF process was employed in this study to improvethe efficiency of ethanol fermentation. Adapted K. marxianus KCTC7150 using the two-phase SSF process produced 13.5 g/1 with an ethanol yield (YEtoH) of 0.35 at 96 h. Development of the two-phase SSF process could enhance the overall ethanol fermentation yields of the seaweed K. alvarezii.