36B-1

K. Y. YOON¹, E. E. Woodams², and Y. D. Hang². (1) Food Science and Technology, Cornell Univ., New York State Agricultural Experiment Station, 630 W. North St., Geneva, NY 14456-1371, (2) Food Science & Technology, Cornell Univ., New York State Agricultural Experiment Station, 630 W. North St., Geneva, NY 14456-1371

Corn residues are the large volume solid wastes that result from the sweet corn processing industry. They are currently either used as animal feed or are returned to the harvested field for land application. The hemicellulose fraction represents over 40% of the dry matter in corn residues and thus has value as a substrate for production of pentoses (xylose, xylitol, arabinose, xylobiose, and xylooligosaccharides). The hemicellulose can be degraded either by acid or enzymic hydrolysis. Acid hydrolysis liberates pentoses and other products that act as fermentation inhibitor.There is thus a need for a better process for saccharification of hemicellulose. The objective of the present study was to determine the efficacy of three commercial xylanase preparations as a sole enzyme source for the production of pentoses and xylooligosaccharides from the hemicellulose fraction of corn residues. Experiments were conducted in Erlenmeyer flasks each containing the hemicellulose fraction extracted from corn husks or corn cobs and commercial xylanase preparations. Effects of substrate concentration, temperature, pH and reaction time on enzymatic production of pentoses were studied. Monosaccharides, disaccharides and xylooligosaccharides were analyzed by HPLC with a Bio-Rad Aminex HPX-87H column and a RI detector. Rapidase Pomaliq (Gist-brocades) was found to yield significantly more pentoses from corn husks and corn conb than Clarex ML (Genenor) or Validase X (Valley Research). Rapidase Pomaliq was capable of increasing the concentraion of pentoses from an initial value of 106.5 to 210.6 g/kg dry matter of corn husks or 8.6 to 141.6 g/dry matter of corn cobs, respectively. Products of the enzymatic reaction were identified as arabinose, xylose, xylobiose, and xylotriose. The results of this study indicate that Rapidase Pomaliq, an enzyme preparation derived from Aspergillus niger and Trichoderma reesei, could serve as a sole enzyme source for the production of pentoses and xylooligosaccharides from corn residues.

Session 36B, Biotechnology: General
8:30 AM - 12:00 PM, Monday AM Room Hall I-2

2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana