Application Studies on Product-Immobilization Phenomenon Newly Discovered

最近我们在淀粉颗粒的酶消化中发现了“产物固定化”，即产物与颗粒一起沉淀。该现象对于i）在较少能量下容易回收产物和ii）将有效化合物包含到多糖中具有重要意义。本项目针对这一现象进行了基础研究，并尝试建立未利用或低利用率的多糖在食品工业中的应用。所得结果如下：(1)纤维素。 i) 在纤维素酶降解纤维素的过程中也发现了产物固定化。 ii)沉淀物纤维素中的产物是短链的水溶性低聚糖。 iii)通过向反应混合物中添加乙醇来增加内部产物。纤维素中的糖类在低浓度乙醇下很容易回收。 iv) 使用乙醇生产低聚糖。酶反应后弃去上清液，然后向沉淀中加入水，释放出不同大小的寡糖。通过凝胶过滤和HPLC进行分离。(2)几丁质和木聚糖。 i) 在酶降解中，还发现了产物固定化。然而，与淀粉颗粒和纤维素相比，其含量较小。 ii)添加乙醇增加了两种多糖中的产物。 (3)以多孔淀粉颗粒为包合物。 i)通过酶处理制备各种植物来源的多孔淀粉颗粒。颗粒表面有孔的淀粉和无孔的淀粉有两种。 ii)孔径可以通过酶的量和处理时间来控制。 iii) 小孔颗粒能够掺入短链低聚糖，长链低聚糖进入大孔淀粉中。 iv)抗坏血酸也被掺入到多孔淀粉颗粒中。将包含抗坏血酸的颗粒转移到水中后，该化合物逐渐释放到水中。较少的

Recently we have found the "immobilization of product" in the enzyme-digestion of starch granule, in which the product precipitates with granule. The phenomenon is of importance in i) the easy recovery of product under the less energy and ii) the inclusion of effective compounds into the polysaccharide. In this project, the fundamental study was done to learn the phenomenon, and the application of unutilized or low-utilized polysaccharides to the food industry was tried to be established. The results obtained were as follows.(1) Cellulose. i) The product-immobilization was also found in the degradation of cellulose by cellulase. ii) Products in the cellulose of precipitate were water-soluble oligosaccharides of short-chain. iii) The inside product increased by addition of ethanol to reaction mixture. Saccharides in the cellulose was easily recovered under the low concentration of ethanol. iv) Production of oligosaccharides was done using ethanol. After enzyme reaction the supernatant w … More as discarded, and then water was added to the precipitate, releasing oligosaccharides of different size. Isolation was done by gel-filtration and HPLC.(2) Chitin and xylan. i) In the enzymatic degradation, the product-immobilization was also found. However, the included amount was small as compared with starch granule and cellulose. ii) The addition of ethanol increased products in the two polysaccharides. (3) Porous starch granule as inclusion material. i) Porous starch granules of various plant origins were prepared by enzyme treatment. There were two types of starches which formed pores or no pore on the surface of granule. ii) The pore size could be controlled by amount and treatment time of enzyme. iii) The smallporous granule was able to incorporate the short-chain oligosaccharides, and the long-chain one entered the starch of large pore. iv) Ascorbic acid was also incorporated into the porous starch granule. After the granule including ascorbic acid was transferred into water, the compound gradually released into water. Less