title: A comparison of the production of ethanol between simultaneous saccharification and fermentation and separate hydrolysis and fermentation using unpretreated cassava pulp and enzyme cocktail.
abstract: The processes of separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) were employed using Saccharomyces cerevisiae for the production of ethanol from cassava pulp without any pretreatment. A combination of amylase, cellulase, cellobiase, and glucoamylase produced the highest levels of ethanol production in both the SHF and the SSF method. A temperature of 37 °C, a pH of 5.0, and an inoculum size of 6% were the optimum conditions for SSF. For the batch process at a pulp concentration of 20%, ethanol production levels from SHF and SSF were the highest, at 23.51 and 34.67 g L(-1) respectively, but in the fed-batch process, the levels of ethanol production from SHF and SSF rose to 29.39 and 43.25 g L(-1) respectively, which were 25% and 24.7% higher than those of the batch process. Thus SSF using the fed-batch provided a more efficient method for the utilization of cassava pulp.
authors.affiliation: School of Bioscience and Bioengineering, South China University of Technology, Guangzhou Higher Education Mega Center, Panyu, Guangzhou, People's Republic of China. mjzhu@scut.edu.cn
authors.forename: Mingjun
authors.initials: M
authors.lastname: Zhu
authors.forename: Ping
authors.initials: P
authors.lastname: Li
authors.forename: Xinfang
authors.initials: X
authors.lastname: Gong
authors.forename: Jufang
authors.initials: J
authors.lastname: Wang
mesh_terms: D000681:Amylases / Q000378:metabolism; D055162:Biocatalysis; D002480:Cellulase / Q000378:metabolism; D002482:Cellulose / Q000378:metabolism; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation; D005087:Glucan 1,4-alpha-Glucosidase / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D002365:Manihot / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D013696:Temperature; D001617:beta-Glucosidase / Q000378:metabolism
chemical_list: D000431:Ethanol; D002482:Cellulose; D000681:Amylases; D001617:beta-Glucosidase; D005087:Glucan 1,4-alpha-Glucosidase; D002480:Cellulase; D005947:Glucose