Enzyme Production by Wood-Rot and Soft-Rot Fungi Cultivated on Corn Fiber Followed by Simultaneous Saccharification and Fermentation

Shrestha, Prachand
Khanal, Samir
van Leeuwen, Johannes
Pometto, Anthony
van Leeuwen, Johannes
Journal Title
Journal ISSN
Volume Title
Research Projects
Organizational Units
Journal Issue

This research aims at developing a biorefinery platform to convert lignocellulosic corn fiber into fermentable sugars at a moderate temperature (37 °C) with minimal use of chemicals. White-rot (Phanerochaete chrysosporium), brown-rot (Gloeophyllum trabeum), and soft-rot (Trichoderma reesei) fungi were used for in situ enzyme production to hydrolyze cellulosic and hemicellulosic components of corn fiber into fermentable sugars. Solid-substrate fermentation of corn fiber by either white- or brown-rot fungi followed by simultaneous saccharification and fermentation (SSF) with coculture of Saccharomyces cerevisiae has shown a possibility of enhancing wood rot saccharification of corn fiber for ethanol fermentation. The laboratory-scale fungal saccharification and fermentation process incorporated in situ cellulolytic enzyme induction, which enhanced overall enzymatic hydrolysis of hemi/cellulose components of corn fiber into simple sugars (mono-, di-, and trisaccharides). The yeast fermentation of the hydrolyzate yielded 7.8, 8.6, and 4.9 g ethanol per 100 g corn fiber when saccharified with the white-, brown-, and soft-rot fungi, respectively. The highest ethanol yield (8.6 g ethanol per 100 g initial corn fiber) is equivalent to 35% of the theoretical ethanol yield from starch and cellulose in corn fiber. This research has significant commercial potential to increase net ethanol production per bushel of corn through the utilization of corn fiber. There is also a great research opportunity to evaluate the remaining biomass residue (enriched with fungal protein) as animal feed.

<p>Posted with permission from <em>Journal of Agricultural and Food Chemistry</em> 57 (2009): 4156–4161, doi:<a href="http://dx.doi.org/10.1021/jf900345n" target="_blank">10.1021/jf900345n</a>. Copyright 2009 American Chemical Society.</p>
Biorenewable Resources and Technology, Food Science and Human Nutrition, Agricultural and Biological Engineering, Lignocellulosic biomass, corn fiber, solid-substrate fermentation, simultaneous saccharification and fermentation, enzymatic hydrolysis, ethanol, fungi, Phanerochaete chrysosporium, Gloeophyllum trabeum, Trichoderma reesei, Saccharomyces cerevisiae