Clostridium species strain BOH3 tolerates and transforms inhibitors from horticulture waste hydrolysates

Abstract

Conversion of lignocellulosic hydrolysate to biofuels is impeded by the toxic effects of inhibitors that are generated during pretreatment and hydrolysis processes. Here we describe a wild-type Clostridium sp. strain BOH3 with high tolerance to the lignocellulose-derived inhibitors and its capability to transform these inhibitors. Strain BOH3 is capable of tolerating over 60 mM furfural, 60 mM hydroxymethylfurfural, and 6.6 mM vanillin, respectively, and is able to convert 53.74 ± 0.37 mM furfural into furfuryl alcohol within 90 h. The high furfural tolerance and its biotransformation by strain BOH3, which is correlated to the high transcription levels of two short-chain dehydrogenase/reductases, enable strain BOH3 to produce 5.15 ± 0.52 g/L butanol from dilute sulfuric acid pretreated horticultural waste hydrolysate (HWH) that bypassed the detoxification step. The capability of strain BOH3 to produce butanol from un-detoxified HWH lays the foundation of cost-effective biofuel production from lignocellulosic materials.

Establishment of Kluyveromyces marxianus as a Microbial Cell Factory for Lignocellulosic Processes: Production of High Value Furan Derivatives

“…Furfuryl alcohol production from furfural has also been previously described. To the extent of our knowledge, the furfuryl alcohol productivities presented in our work using glucose as a co-substrate (2.89 g/L/h from 33.5 mM of furfural, and 5.74 g/L/h from 66 mM of furfural) were the highest among the reported for yeast [50][51][52] and bacteria [53][54][55][56][57] in a batch using a synthetic medium. Moreover, the productivities obtained in our work using xylose as co-substrate (3.18 g/L/h from 33.5 mM of furfural, and 6.46 g/L/h from 66 mM of furfural) were also the highest among the reported for yeast [58,59] in a batch using a synthetic medium.…”

Butanol–isopropanol fermentation with oxygen-tolerant Clostridium beijerinckii XH29

“…Lignocellulosic biomass is an abundant and sustainable resource with great potential as a feedstock for microbial fermentation. Since the beginning of the twenty-first century, many investigations have studied on the use of lignocellulosic hydrolysate as substrate for butanol production (Ezeji et al 2007 ; Lee et al 2016 ; Li et al 2018 ; Qureshi et al 2010 ; Yan and He 2017 ; Zhang et al 2020 ). However, compared with glucose fermentation, this substrate presents a series of challenges for microbial growth (Li et al 2018 ).…”

“…However, compared with glucose fermentation, this substrate presents a series of challenges for microbial growth (Li et al 2018 ). Lignocellulose must be pretreated to generate soluble sugars for butanol fermentation, a process that also forms inhibitors (Jonsson and Martin 2016 ; Yan and He 2017 ). To release the inhibition of ABE fermentation, several detoxification methods have been developed.…”