In:
Holzforschung, Walter de Gruyter GmbH, Vol. 73, No. 1 ( 2018-12-19), p. 55-64
Abstract:
Acetone-butanol-ethanol (ABE) fermentation has a high potential for industrial application in lignocellulose-based biorefinery. Nevertheless, strong end-product inhibition is a severe limitation of this process, which can be partially solved by in situ product recovery techniques, such as extractive fermentation. In this work, the hydrolyzed cellulose from organosolv pre-treated beech wood ( Fagus sylvatica L.) was fermented by Clostridium beijerinckii CECT 508 and compared with synthetic P2 medium in conventional and extractive fermentation processes. The conventional control fermentation yielded 9.12 g l −1 of ABE with C. beijerinckii CECT 508, while ABE overproduction of 40% was observed with cellulose hydrolysate as a substrate. After extractive batch fermentation based on 2-butyl-1-octanol as extractant, the final ABE titer was doubled in the P2 control medium over the conventional batch, with respective increases of 50, 190, and 140% for butanol (B), acetone (A) and ethanol (E). In the case of ABE as a hydrolysate medium, the total production increased by 10% with liquid extraction, while mainly B was responsible for this improvement. The total productivity was nevertheless gradually decreased in extractive fermentation, with a significantly slower production rate and the microbial growth compared to conventional fermentation. Moreover, solvent production and sugar consumption stopped, although the aqueous B concentration was below the inhibition threshold. The mid-term toxicity of the extraction solvent 2-butyl-1-octanol seems responsible for these results and this issue should be considered in future research.
Type of Medium:
Online Resource
ISSN:
1437-434X
,
0018-3830
DOI:
10.1515/hf-2018-0098
Language:
English
Publisher:
Walter de Gruyter GmbH
Publication Date:
2018
detail.hit.zdb_id:
1466072-6
SSG:
23
Bookmarklink