For the purpose of utilizing agricultural waste products for animal feeds, chemical analysis of some important agricultural wastes in Korea and enzymatic hydrolysis of rice hull were undertaken and summarized as follows:
1) Rice hull and straws of rice, barley and wheat were analyzed for their proximate principles and carbohydrate composition.
2) A strain of Aspergillus niger was selected as having the highest productivity of rice hull decomposing activity among many species of molds. The optimum conditions for the culture on washed wheat bran were. 3 days of culture period, 55% moisture content and neutral pH and one hour was proper for the extraction of enzymes.
3) The extent of hydrolysis of xylan and rice hull by a crude enzyme preparation from this strain was 63% and 7%, respectively, and the optimun pH for its activity was 4.0 and 4.5, respectively.
4) Enzymatic hydrolysis of rice hull was generally suppressed by gamma-ray irradiation (0.5∼5 Mrad, in dry state), but the effect was less by irradiation in wet state.
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