Challenges in enzymatic hydrolysis and fermentation of pretreated Arundo donax revealed by a comparison between SHF and SSF
Journal article, 2012

The perennial herbaceous crop Arundo donax is a potential feedstock for second-generation bioethanol production. In the present work, two different process options were investigated for the conversion of two differently steam-pretreated batches of A. donax. The pretreated raw material was converted to ethanol with a xylose-consuming Saccharomyces cerevisiae strain, VTT C-10880, by applying either separate hydrolysis and fermentation (SHF) or simultaneous saccharification and fermentation (SSF). The highest overall ethanol yield and final ethanol concentration were achieved using SHF (0.27 g g(-1) and 20.6 g L-1 compared to 0.24 g g(-1) and 19.0 g L-1 when SSF was used). The performance of both SHF and SSF was improved by complementing the cellulolytic enzymes with hemicellulases. The higher amount of acetic acid in one of the batches was shown to strongly affect xylose consumption in the fermentation. Only half of the xylose was consumed when batch 1 (high acetic acid) was fermented, compared to that 94% of the xylose was consumed in fermentation of batch 2 (lower acetic acid). Furthermore, the high amount of xylooligomers present in the pretreated materials considerably inhibited the enzymatic hydrolysis. Both the formation of xylooligomers and acetic acid thus need to be considered in the pretreatment process in order to achieve efficient conversion of A. donax to ethanol.

fermentation

SHF

Giant reed

Acetic acid stress

simultaneous saccharification

exploded wheat-straw

Arundo donax

acetic-acid

glucose

saccharomyces-cerevisiae tmb3400

genetically-engineered strain

xylose

bioethanol production

SSF

ethanol-production

Xylooligomers

corn stover

Author

Magnus Ask

Chalmers, Chemical and Biological Engineering, Industrial biotechnology

K. Olofsson

Lund University

T. Di Felice

L. Ruohonen

Technical Research Centre of Finland (VTT)

M. Penttila

Technical Research Centre of Finland (VTT)

G. Liden

Lund University

Lisbeth Olsson

Chalmers, Chemical and Biological Engineering, Industrial biotechnology

Process Biochemistry

1359-5113 (ISSN)

Vol. 47 10 1452-1459

Subject Categories

Industrial Biotechnology

Chemical Sciences

DOI

10.1016/j.procbio.2012.05.016

More information

Latest update

4/24/2018