ARS | Publication request: Bioconversions of Agricultural Residues to Value-Added Coproducts Using Yeastlike Fungi

Submitted to: Federation Of European Microbiological Societies Yeast Research
Publication Type: Review Article
Publication Acceptance Date: November 22, 2002
Publication Date: January 24, 2003
Citation: Leathers, T.D. 2003. Bioconversions of maize residues to value-added coproducts using yeastlike fungi. Federation of European Microbiological Societies Yeast Research. 3:133-140.

Technical Abstract: Agricultural residues are abundant potential feedstocks for bioconversions to industrial fuels and chemicals. Every bushel of corn (maize) processed for sweeteners, oil, or ethanol generates nearly 7 kg of protein- and fiber-rich residues. Currently, these materials are sold for very low returns as animal feed ingredients. Although corn fiber (pericarp) arabinoxylan is particularly resistant to digestion by commercially available enzymes, a partial saccharification was achieved using a crude mixture of enzymes from the yeastlike fungus Aureobasidium. Xylose derived from corn fiber may be converted to ethanol or xylitol using a variety of naturally occurring or recombinant yeasts. Pichia guilliermondii was employed in a two-stage fermentation scheme for xylitol production from corn fiber hydrolysates. Stillage residues from corn-based fuel ethanol production were converted to the polysaccharide pullulan using Aureobasidium, and the red yeast Phaffia rhodozyma was used for production of the carotenoid astaxanthin.