Shen, Fei; Kumar, Linoj; Hu, Jinguang; Saddler, Jack N.
초록
<P><B>Highlights</B></P><P>► Xylanase and delignification were applied for enzymatic hydrolysis and fermentation. ► Delignification markedly improved hydrolysis and ethanol production in SHF and SSF. ► Xylanase supplementation was only positive to SHF while retarded SSF seriously. ► Xylanase improved xylan removal and consequently enhanced ethanol production in SHF. ► Protein stress or bacteriolysis of xylanase was possible reasons for retarding SSF.</P> <P><B>Abstract</B></P><P>Steam-pretreated sweet sorghum bagasse (SSB) and Douglas-fir (DF) were employed for SHF and SSF to evaluate the effects of xylanase supplementation and delignification on ethanol production. Results indicated final ethanol concentration in SHF could reach 28.4g/L (SSB) and 20.4g/L (DF) by xylanase supplementation with the increase of 46% and 61% in comparison with controls. The delignification could significantly enhance final ethanol concentration to 31.2g/L (SSB) and 30.2g/L (DF) with the increase of 61% and 138%. In SSF, final ethanol concentration in the delignified SSB and DF arrived at 27.6g/L and 34.3g/L with the increase of 26% and 157% compared with controls. However, only 2.2g/L (SSB) and 6.9g/L (DF) ethanol were obtained with xylanase supplementation. According to these results, it could be concluded that delignification was beneficial to improve ethanol production of SHF and SSF. The xylanase supplementation (0.12g protein/g glucan) was only positive to SHF while retarded SSF seriously.</P>