High temperature pre-digestion of corn stover biomass for improved product yields

Biotechnology for Biofuels

Roman Brunecky²  Sarah E Hobdey²  Larry E Taylor²  Ling Tao¹  Melvin P Tucker¹  Michael E Himmel²  Stephen R Decker² 

[1] National Bioenergy Center, National Renewable Energy Laboratory, 15013, Denver, West Parkway, Golden 80401, CO, USA

[2] Chemical Biosciences Center, National Renewable Energy Laboratory, 15013, Denver, West Parkway, Golden 80401, CO, USA

关键词: Thermotoga maritima;    Acidothermus cellulolyticus;    Caldicellulosiruptor bescii;    E1;    CelA;    Enzymatic hydrolysis;    Pretreatment;    Biomass;   

Others  :  1084222
DOI  :  10.1186/s13068-014-0170-2

 received in 2014-08-26, accepted in 2014-11-14,  发布年份 2014

【 摘 要 】

Introduction

The efficient conversion of lignocellulosic feedstocks remains a key step in the commercialization of biofuels. One of the barriers to cost-effective conversion of lignocellulosic biomass to sugars remains the enzymatic saccharification process step. Here, we describe a novel hybrid processing approach comprising enzymatic pre-digestion with newly characterized hyperthermophilic enzyme cocktails followed by conventional saccharification with commercial enzyme preparations. Dilute acid pretreated corn stover was subjected to this new procedure to test its efficacy. Thermal tolerant enzymes from Acidothermus cellulolyticus and Caldicellulosiruptor bescii were used to pre-digest pretreated biomass at elevated temperatures prior to saccharification by the commercial cellulase formulation.

Results

We report that pre-digestion of biomass with these enzymes at elevated temperatures prior to addition of the commercial cellulase formulation increased conversion rates and yields when compared to commercial cellulase formulation alone under low solids conditions.

Conclusion

Our results demonstrating improvements in rates and yields of conversion point the way forward for hybrid biomass conversion schemes utilizing catalytic amounts of hyperthermophilic enzymes.

【 授权许可】

   
2014 Brunecky et al.; licensee BioMed Central Ltd.

【 图 表 】

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