利用纖維素分解?的吸附以水解處理過之稻草

Abstract

由TrichodermareeseiQM9414培養所得酵素液研究水解處理過之稻草吸附的情形，測酵素活性時發現(Cx、C1、FPcellulase及β-glucosidase均會瞬時吸附於稻草上，在反應一段時間後(Cx、FPcellulase會釋回反應液並穩定存於反應液中。Xylanase除在稀釋酵素液有瞬時吸附外，其餘均無瞬時吸附及釋回反應液的現象發生。 連續添加酵素，改變稻草顆粒大小、濃度，粗酵素液濃度，酸鹼值均會影響吸附百分比，添加化學物質及反應溫度在5-50℃之間對吸附沒有影響，但溫度因數對酵素活性則影響顯著。 以5%稻草為基質進行糖化，反應24小時糖化率可達72-82%，而以7.5%的稻草進行可達64-67%,分析水解濾液還原糖成分，其中葡萄糖佔49.47%，木糖則佔38.27%。利用酵素的穩定性於反應液中不斷的添加稻草以增加還原糖量，在反應第九天後總稻草添加量為19%時可得175.85mg/ml的還原糖量。糖化所得還原糖含高量的葡萄糖及木糖對進一步利用稻草非常有利

The adsorption of ceilulase and xylanase from Trichodorma reesei QM 9414 was studied during the hydrolysis of NaOH-treated rice straw. By measuring individual activities, it was found Cx, C1 FP celiulases and β-g1ucosidase were adsorbed almost instantaneously on the rice straw, afterward Cx cellulase and FP ceilulase would release black to the reaction mixture and exist in the solution stably for a long time. Xylanase did not show instantaneously adsorption except at low concentration and did not release at all. Consecutive addition of enzyme and changes in the particle size of rice straw, the concentration of the rice straw, the concentration of the crude enzyme solution and the initial pH would affect the percentage of adsorption. Addition of chemicals and change in the reaction temperature from 5 to 50℃will not affect the adsorption, but temperature factor has a significant effect to the activity of enzyme. Saccharification could reach to 72-82% after 24 hours incubation with 5％ rice straw as substrate, and 64-67％ with 7.5％ rice straw. To analyze the composition of reducing sugar in the hydrolysate, it contained 49.47％ glucose and 38.27％ xylose. Since most of the enzymes existed stably in the hydrolysate and on the substrate, therefore rice straw would be added consecutively to increase the amount of sugar production. After adding a total amount of 19％ rice straw at the 9th day, 175.85mg/ml of reducing sugar was obtained. These high yield of reducing sugar mainly containing glucose and xylose would make the rice straw more ultilizable.