HEMICELLULOSE CONVERSION BY ANAEROBIC-DIGESTION

This research was undertaken to study the digestibility of the hemicellulose fractions of an aquatic biomass, a land-based biomass and a biomass-waste blend under various fermentation conditions. The conversion of hemicellulose was higher than those of cellulose and protein under the mesophilic condition. Hemicellulose was converted at a much lower efficiency than cellulose during thermophillic digestion. In contrast, cellulose conversion was about the same under mesophilic and thermophilic conditions. Cellulose was utilized in preference to hemicellulose during mesophilic fermentation of nitrogen-supplemented Bermuda grass. It was speculated that Bermuda grass cellulose was converted at a higher efficiency than hemicellulose in the pressure of external nitrogen because the metabolism of the breakdown product (glucose) of celluloe requires the least investment of enzymes and energy.