Bioabatement to Remove Inhibitors from Biomass-Derived Sugar Hydrolysates

Abstract

Bioabatement is a potential method to remove inhibitory compounds from lignocellulose hydrolysates that could be incorporated into a scheme for fermentation of ethanol from cellulose. Coniochaeta ligniaria NRRL30616, an Ascomycete that metabolizes furfural and 5-hydroxymethylfurfural, is a unique strain that may be useful for detoxifying biomass sugars. NRRL30616 and 23 related fungal strains were screened for the ability to metabolize furans and grow in dilute-acid hydrolysate of corn stover. NRRL30616 was the best strain for removal of inhibitors from hydrolysate, and abatement of hydrolysate by inoculation with the strain allowed subsequent yeast fermentation of cellulose to ethanol.

Biological detoxification of furfural and 5-hydroxyl methyl furfural in hydrolysate of oil palm empty fruit bunch by Enterobacter sp. FDS8

“…The isolated bacterial strain FDS8 showed the highest furfural degradation rate with its 16S rDNA being sequenced ( [2,4,6,[9][10][11]14]. However, bacteria of the genus Enterobacter had not yet been reported to degrade furfural and HMF in lignocellulose hydrolysate.…”

“…However, the efficiency of biological detoxification is usually low. The highest degradation rates of furfural and HMF were reported to be 0.1 and 0.02 g L −1 h −1 , respectively, with detoxification processes taking 1-4 days to complete [2,6,[9][10][11][12][13][14]. The low efficiency of biological degradation severely limits its practical applications.…”

Hydrothermal pretreatment of sugarcane bagasse using response surface methodology improves digestibility and ethanol production by SSF

“…Our laboratory has had success at conditioning hydrolysates by using biological abatement to metabolize the inhibitory furans and phenolics [13][14][15]. The hydrolysates are abated using a specific isolate of C. ligniaria that mineralizes a wide spectrum of inhibitor-associated organic compounds, including phenolics and furans, and does so preferentially to sugars.…”

“…The hydrolysates are abated using a specific isolate of C. ligniaria that mineralizes a wide spectrum of inhibitor-associated organic compounds, including phenolics and furans, and does so preferentially to sugars. Furthermore, treatment with C. ligniaria has been shown to improve fermentations of a wide variety of dilute acid-treated feedstocks hydrolysates [13][14][15]. In this study, bioabatement with C. ligniaria was evaluated on hydrothermally pretreated sugarcane bagasse (Fig.…”

Role of pretreatment and conditioning processes on toxicity of lignocellulosic biomass hydrolysates

“…Furfural was removed first followed by HMF, but furfural degradation only took place in the presence of HMF. Follow up work evaluated additional fungal strains for the ability to metabolize furans and grow in dilute acid hydrolysate of corn stover (Nichols et al 2005). Seven of 23 could grow with furfural as sole C source.…”