Biological treatment of eucalypt spent sulphite liquors: A way to boost the production of second generation bioethanol

authors	Pereira, SR; Ivanusa, S; Evtuguin, DV; Serafim, LS; Xavier, AMRB
nationality	International
journal	BIORESOURCE TECHNOLOGY
author keywords	Biological treatment; Detoxification; Hardwood (eucalypt) spent sulphite liquor; Second generation bioethanol
keywords	FUNGUS PAECILOMYCES-VARIOTII; PICHIA-STIPITIS; SYRINGIC ACID; ETHANOL; DEGRADATION; INHIBITION; SELECTION; XYLOSE
abstract	The fermentation of reducing sugars from hardwood (eucalypt) spent sulphite liquor (HSSL) into ethanol by Pichia (Scheffersomyces) stipitis is hindered by concomitant inhibitors of microbial metabolism. The conditions for the HSSL biological treatment step by Paecilomyces variotii were evaluated and optimised. Two different strategies of reactor operation were compared using single batch (B) and sequential batch reactor (SBR). Biological treatment of HSSL in the SBR revealed the best results with respect to the removal of microbial inhibitors. Also, most of inhibitory compounds, acetic acid, gallic acid, pyrogallol, amongst others, were removed from HSSL by P. variotii before the ethanol fermentation. The bio-detoxified HSSL was subjected to a successful fermentation by P. stipitis, attaining a maximum ethanol concentration of 2.4 g L(-1) with a yield of 0.24 g ethanol g sugars(-1). (C) 2011 Elsevier Ltd. All rights reserved.
publisher	ELSEVIER SCI LTD
issn	0960-8524
year published	2012
volume	103
issue	1
beginning page	131
ending page	135
digital object identifier (doi)	10.1016/j.biortech.2011.09.095
web of science category	Agricultural Engineering; Biotechnology & Applied Microbiology; Energy & Fuels
subject category	Agriculture; Biotechnology & Applied Microbiology; Energy & Fuels
unique article identifier	WOS:000298273600019