Enzymatic hydrolysis of sodium dodecyl sulphate (SDS)-pretreated newspaper for cellulosic ethanol production by Saccharomyces cerevisiae and Pichia stipitis.
Fermentation of enzymatic hydrolysate of waste newspaper was investigated for cellulosic ethanol production in this study. Various nonionic and ionic surfactants were applied for waste newspaper pretreatment to increase the enzymatic digestibility. The surfactant-pretreated newspaper was enzymatically digested in 0.05 M sodium citrate buffer (pH 4.8) with varying solid content, filter paper unit loading (FPU/g newspaper), and ratio of filter paper unit/beta-glucosidase unit (FPU/CBU). Newspaper pretreated with the anionic surfactant sodium dodecyl sulphate (SDS) demonstrated the highest sugar yield. The addition of Tween-80 in the enzymatic hydrolysis process enhanced the enzymatic digestibility of newspaper pretreated with all of the surfactants. Enzymatic hydrolysis of SDS-pretreated newspaper with 15% solid content, 15 FPU/g newspaper, and FPU/CBU of 1:4 resulted in a newspaper hydrolysate conditioning 29.07 g/L glucose and 4.08 g/L xylose after 72 h of incubation at 50 degrees C. The fermentation of the enzymatic hydrolysate with Saccharomyces cerevisiae, Pichia stipitis, and their co-culture produced 14.29, 13.45, and 14.03 g/L of ethanol, respectively. Their corresponding ethanol yields were 0.43, 0.41, and 0.42 g/g.
Xin
Fengxue
F
School of Life Sciences and Chemical Technology, Ngee Ann Polytechnic, 535 Clementi Road, Singapore 599489, Singapore.
Geng
Anli
A
Chen
Ming Li
ML
Gum
Ming Jun Marcus
MJ
D002482:Cellulose / Q000737:chemistry / Q000378:metabolism*; D000431:Ethanol / Q000378:metabolism; D005285:Fermentation; D005656:Fungal Proteins / Q000378:metabolism*; D006868:Hydrolysis; D010209:Paper; D010843:Pichia / Q000201:enzymology / Q000378:metabolism*; D012037:Refuse Disposal / Q000379:methods*; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000378:metabolism*; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry
D005656:Fungal Proteins; D012967:Sodium Dodecyl Sulfate; D000431:Ethanol; D002482:Cellulose