現今紙的使用已是遍佈人類生活中以及整個社會,且隨著科學的進步,紙的利用越來越廣,紙的需求也是越來越多。工業上製造紙張的纖維原料,即是高等植物細胞壁,主要成份是纖維素(cellulose)、及少量半纖維素(hemicellulose)和木質素(lignin),因此我們希望能將廢紙回收利用,以纖維酵素將多醣類的纖維素分解成為有經濟價值的葡萄糖。 實驗是將纖維酵素使用褐藻酸鈉及氯化鈣將纖維酵素固定在褐藻酸鈣凝膠內,使纖維酵素不會因反應而流失,且可增加其穩定性,以及回收再利用。其製作過程是將含纖維酵素之藻酸鈉溶液滴入氯化鈣水溶液使其形成直徑平均大小為4.190±0.291 mm褐藻酸鈣膠囊,纖維酵素即固定在此褐藻酸鈣膠囊裡。此固定化纖維酵素再經與5 M硫酸處理後之廢紙纖維素反應,先以錐形瓶恆溫振盪方式找出pH 4.0及溫度45℃之最適水解條件,再以此條件進行放大水解反應,並將反應發酵槽設計為懸掛式固定化纖維酵素進行反應。反應產物的分析使用高效液相色層分析(High Performance Liquid Chromatography 簡稱HPLC),以陽離子交換層析(cation- exchange chromatography)管柱進行層析,發現有葡萄糖、木糖和纖維雙糖等主要產物。經此特別的反應器設計,反應結果相較於未固定化纖維酵素反應或懸浮式固定化纖維酵素反應有更好的結果,且反應結果易於將固定化纖維酵素回收,以水清洗後可回復部份之酵素活性。
Today, the use of paper is popular in our life and all over the whole society. Accompanied with the progress of science, the need of paper is getting more and more and the usage of paper is more and more wider. The raw material of paper comes form the cell wall of the higher plant. The main component is the cellulose and hemicellulose and lignin are the minor parts. Therefore, we want to recycle the waste paper and use again. In out laboratory, we used free cellulase to hydrolyze the waste paper cellulose to produce the more useful and valuable glucose. In this research, the waste paper collected in the laboratory was pretreated with 5 M H2SO4 solution. The pretreated waste paper cellulose was then reacted with the immobilized cellulase. The immobilization of cellulase was through the calcium alginate gel that can form a capsule of average diameter 4.190±0.291 mm to entrap the cellulase. The optimum conditions found for the waste paper cellulose hydrolysis with immobilized cellulase were a pH 4.0 and a temperature at 45℃ by a shaketr-flask type reaction. The scale-up reaction was performed by a special designed reactor that the immobilized cellulase pellets were filled in a net and hung under a rack to form a fixed-bed-like reactor. The hydrolysis products were analyzed by high-perfromance liquid chromatography (HPLC) and with a cation-exchange column. The major products are glucose, xylose, and cellobiose. The production of glucose was better by the use of this special designed reactor than the hydrolysis results with free cellulase or the suspended immobilized cellulase. Another advantage of the hanging type immobilized cellulase reactor is the easy recycle of the immobilized cellulase. We found that the activity of the recycled immobilized cellulase can be recovered in a small extent by washing with distilled waster.