Enhancement of fermentable sugar yield by competitive adsorption of non-enzymatic substances from yeast and cellulase on lignin

BMC Biotechnology

Yong Tang¹  Fuhou Lei¹  Carrasco Cristhian²  Zuguang Liu¹  Hailong Yu³  Jianxin Jiang³ 

[1] GuangXi Key Laboratory of Chemistry and Engineering of Forest Products, Nanning 530006, China

[2] Department of Chemical Engineering, Lund University, Lund, Sweden

[3] Department of Chemistry and Chemical Engineering, Beijing Forestry University, Beijing, China

关键词: Competitive adsorption;    Yeast hydrolysate;    Enzymatic hydrolysis;    Cellulases;   

Others  :  834888
DOI  :  10.1186/1472-6750-14-21

 received in 2013-09-06, accepted in 2014-03-12,  发布年份 2014

【 摘 要 】

Background

Enhancement of enzymatic digestibility by some supplementations could reduce enzyme loading and cost, which is still too high to realize economical production of lignocellulosic biofuels. A recent study indicates that yeast hydrolysates (YH) have improved the efficiency of cellulases on digestibility of furfural residues (FR). In the current work, the components of YH were separated by centrifugation and size exclusion chromatography and finally characterized in order to better understand this positive effect.

Results

A 60.8% of nitrogen of yeast cells was remained in the slurry (YHS) after hydrothermal treatment. In the supernatant of YH (YHL), substances of high molecular weight were identified as proteins and other UV-absorbing compounds, which showed close molecular weight to components of cellulases. Those substances attributed to a synergetic positive effect on enzymatic hydrolysis of FR. The fraction of YHL ranged from 1.19 to 2.19 mL (elution volume) contained over 50% of proteins in YHL and had the best performance in stimulating the release of glucose. Experiment results proved the adsorption of proteins in YHL on lignin.

Conclusions

Supplementation of cellulases with YH enhances enzymatic digestibility of FR mainly by a competitive adsorption of non-enzymatic substances on lignin. The molecular weight of these substances has a significant impact on their performance. Different strategies can be used for a good utilization of yeast cells in terms of biorefinery concept.

【 授权许可】

   
2014 Tang et al.; licensee BioMed Central Ltd.

【 图 表 】

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