| Summary: | 碩士 === 大同大學 === 生物工程學系(所) === 98 === In this study, we selected thermotolerant yeasts to produce ethanol from cellulose in the presence of cellulase. This study falled into two sections. The first section was try to find the thermotolerant yeast, which can grow at 40 – 45 ℃. The other section was using the thermotolerant yeast to produce ethanol from cellulose and orange peel waste by simultaneous saccharification and fermention.
Among the fifty strains of thermotolerant yeast that we screened, the most thermotolerant were the Kluyveromyces marxianus genus yeasts. From those Kluyveromyces marxianus genus yeasts, we selected a yeast strain and called it “K21”. Ethanol production was carried out using 7.5 % (w/v) alpha-cellulose as substrate in the percent of AccelleraseTM 1000 and K21 yeast cells by simultaneous saccharification and fermentation (SSF) at 42, and 45 ℃, respectively.
The results indicate that the viability at 42 ℃ was higher than at 45 ℃, and the maximum ethanol concentration were 30 g/L and 45g/L, at 42 ℃ and 45 ℃, respectively.
The orange peel was dried in the 70 ℃ oven and then was ground into powders. Ethanol production was carried out in jar fermenter using orange peel as raw material in the presence of AccelleraseTM 1000, pectinase and K21 yeast cells by SSF. The results indicate that 10 % (w/v) orange peel resulted an ethanol concentration of 17 g/L, and the 20 % (w/v) orange peel led to an ethanol concentration of 33 g/L, respectively.
|
|---|
