Ethanol production by an immobilized thermotolerant mutant of Brettanomyces custersii H1-39 from wood hydrolyzate media

Brettanomyces custersii H1-39 mutant was immobilized with various carriers. Immobilized mutant H1-39 produced more ethanol and showed higher productivity, and cell concentration than those of free H1-39 in 3.4% hydrolyzate of wood-chips at different temperatures (37°C. 40°C and 43°C). At 37°C, ethanol concentration produced by mutant H1-39 immobilized in Ca- alginate and ABG(1% Ca-alginate, 1.67% bentonite. 0.33% glutaraldehyde) bead were higher than those produced by the other carders (ACG: 1% Ca-alginate, 1.67% celite R-634, 0.33% glutaraldehyde, ABP; 1% Ca-alginate, 1.67% bentonite, 0.33% pectin, ACP: 1% Ca-alginate, 1.67% celite R-634. 0.33% pectin). The highest value of productivity(1.23 g/l · h) was obtained by using ABG beads. At 40°C, ethanol concentration and productivity obtained by ABG beads were 15.2 g/L and 0.84 g/L.h. respectively, which showed the highest value compared to other carriers. Particularly, productivity of immobilized cell was increased up to 90% as compared to that of free cell. On the other hand, ABP(1% Ca-alginate+1.67% bentonite+0.33% pectin) beads gave the best results at 43°C for production of ethanol and productivity, which were 13.8 g/l and 0.77 g/l · h, respectively.