Title: Utilization of corn residues for production of the polysaccharide schizophyllan Authors
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: June 6, 2012
Publication Date: June 6, 2012
Citation: Sutivisedsak, N., Leathers, T.D., Nunnally, M.S., Price, N.P. 2012. Utilization of corn residues for production of the polysaccharide schizophyllan [abstract]. Corn Utilization and Technology Conference. Poster 14. Technical Abstract: Abundant corn residues include fiber from wet milling operations and distillers' dried grains from dry grind ethanol plants. Biorefineries of the future will utilize such residues for the production of valuable bioproducts, particularly those traditionally produced from fossil fuels. Schizophyllan is a homoglucan with a ß-1,3-linked backbone and ß-1,6-linked side chains of single glucose units at every other residue. It is produced by the ubiquitous mushroom, Schizophyllum commune. Schizophyllan acts as a biological response modifier and a non-specific stimulator of the immune system. It is currently used primarily in vaccines, anti-cancer therapies, and as a bioactive cosmetics ingredient. However, the unique physical properties of the biopolymer (water solubility, thermal stability, high viscosity, etc.) suggest additional applications as a biomaterial. Schizophyllan is conventionally produced by submerged culture fermentation using glucose as a carbon source. In this study, a variety of renewable cellulosic materials were tested as alternative substrates. Corn residues were identified as promising feedstocks for schizophyllan production. Fermentation conditions were optimized, and the recovered polysaccharide was found to be primarily composed of glucose. NMR and permethylation analyses confirmed the presence of ß-1,3 and ß-1,6 glycosidic linkages characteristic of schizophyllan. Schizophyllan produced from agricultural residues was of a high molecular weight, and exhibited solution viscosity properties similar to those of commercially produced material. We conclude that corn residues are potential substrates for production of the polysaccharide schizophyllan as a value-added bioproduct consistent with the biorefinery concept. Corn-based schizophyllan may have bulk applications as a biobased replacement for certain petroleum-based materials.