Aspergillus oryzae 稱為米麴菌或稱為日本麴黴，由於此菌種的蛋白?作用能力強，長久以來廣泛地使用在傳統食品發酵與釀造工業中。本論文的研究方向在探討利用不同操作策略，在攪拌式發酵槽液態培養Aspergillus oryzae (BCRC30118)生產酸性蛋白?，並提高其酵素產率。接著，將含有酸性蛋白?的發酵液直接添加至黃豆粕中進行水解。在液態培養試驗中，不同的攪拌策略，包括攪拌速率的控制、通氣量和饋料批式，並外接細胞均質機 (polytron) 改變菌體形態，提高酸性蛋白?的生成。首先，在液態培養試驗結果中，攪拌速率 200 rpm、300 rpm其最高酵素活性為 148.76 和187.31 units/ml，而攪拌速率增加為 500 rpm 可提升至 256.52 units/ml。將通氣量提升為 2vvm 時，300 rpm轉速下，酵素活性可提高至 400.87 units/ml，增加了 56 ％。藉著外接式均質機，使菌體形態成菌絲體及更小的菌絲球，在 300 rpm、2 vvm條件下，蛋白?有更佳的酵素活性 536.45 units/ml。饋料批式操作中，經由葡萄糖添加，可將最高酵素活性再提升至 715.71 units/ml，結果為 500 rpm與1 vvm 操作條件所得的二倍多。於黃豆粕水解過程中，其最適溫度和 pH 值分別為 40 ℃、 3.5，而最佳的水解時間為 3 小時，水解率為 26.5 ％。 Aspergillus oryzae has been widely used in traditional fermented foods and fermentation industry due to the capability of high activity of protease. The purpose of this study is to compare different strategies for the production of acid protease by Aspergillus oryzae (BCRC30118). In addition, the enzyme solution produced was added into soybean meal for hydrolyzing. Different operating conditions and strategies were compared in submerged fermentation, which included the control of agitation, aeration and connected with external polytron in order to enhance the production of acid protease. In the beginning, the highest activity at 200rpm and 300rpm were 148.76 units/ml and 187.31 units/ml. By increasing agitation speed to 500rpm, the activity achieved the level of 256.52 units/ml. In contrast, when the aeration rate increased to 2vvm at 300rpm, the protease activity rose to 400.87 units/ml and had the increase of 56％. By connecting an external polytron to destroy the structure of pellet, the highest activity of 536.45 units/ml wasobtained. In the fed-batch operation, the protease activity rose to 715.71 units/ml by feeding glucose solution, which was twice higher than that of the control at 500rpm and 1vvm.The optimum conditions for hydrolyzing soybean meal were determined to be around 40℃,pH=3.5 at the 3th hour and the DH％ obtained was 26.5％.
