Jump to main content
Jump to site search

Issue 102, 2016, Issue in Progress
Previous Article Next Article

Structure dependent toxicity of lignin phenolics and PEG detoxification in VHG ethanol fermentation

Author affiliations

Abstract

The inhibition of lignin phenolics on fermenting microbes has become one of the major barriers in developing an economically viable process for cellulosic ethanol production. In this study, the toxicity to yeast cells and the inhibition to the very high gravity (VHG) fermentation of the phenolic compounds were investigated in the absence or presence of polyethylene glycol (PEG). It was found that the inhibitory effects of phenolic compounds on VHG ethanol fermentation depend on the activity of their hydroxyl (–OH) hydrogen. 250 g L−1 PEG-1000 detoxified 2.0 g L−1 guaiacol in the fermentation broth, and boosted the ethanol concentration from 131 g L−1 to 173 g L−1. The inhibitory effect of 5.0 g L−1 guaiacol on ethanol fermentation was also alleviated, and the ethanol concentration was increased from 51 g L−1 to 151 g L−1 after detoxification with 250 g L−1 PEG-1000. The 1H-NMR of hydroxyl group (–OH) of phenolic compounds in PEG revealed the role of hydrogen bonding formation on the in situ detoxification mechanism of PEG, and the order in the strength of the intermolecular hydrogen bond between phenolic compounds and PEG. Furthermore, the kinetics of VHG ethanol fermentation in the presence of phenolic compounds were determined. The obtained kinetic model (phenolic compounds inhibitory effect) fits well the kinetics of ethanol production from lignocellulosic hydrolyzates using batch VHG ethanol fermentation technology.

Graphical abstract: Structure dependent toxicity of lignin phenolics and PEG detoxification in VHG ethanol fermentation

Back to tab navigation

Supplementary files

Publication details

The article was received on 17 Aug 2016, accepted on 13 Oct 2016 and first published on 14 Oct 2016


Article type: Paper
DOI: 10.1039/C6RA20693J
Citation: RSC Adv., 2016,6, 99924-99932
  •   Request permissions

    Structure dependent toxicity of lignin phenolics and PEG detoxification in VHG ethanol fermentation

    X. Liu, P. Yan, W. Xu and Z. C. Zhang, RSC Adv., 2016, 6, 99924
    DOI: 10.1039/C6RA20693J

Search articles by author

Spotlight

Advertisements