Pullulanase is a debranching enzyme that cleaves explicitly α-1,6 glycosidic bonds, which is widely used in starch saccharification, production of glucose, maltose, and bioethanol. The thermal-resistant pullulanase is isolated from a variety of microorganisms; however, the lack of industrial production of pullulanase has hindered the transformation of the laboratory to industry. In this study, the expensive maltose syrup and soybean meal powder were replaced with cheap corn starch and corn steep liquor, exhibiting 440 U/mL of pullulanase in shake flasks by changing the C/N value and the total energy of the medium. Subsequently, the cultivation conditions were explored in a 50-L and 50-m³ bioreactor. In batch culture, the pullulanase activity reached 896 U/mL, while it increased to 1743 U/mL in fed-batch culture by controlling the dissolved oxygen, pH, reducing sugar content, and temperature. Remarkably, the cultivation volume was enlarged to 50 m³ based on the technical parameters of fed-batch culture. The industrial production of pullulanase was successful, and the activity achieved 1546 U/mL. When the product was stored at room temperature (25 °C) for 6 months, the pullulanase activity was over 90%. The half-lives at 60 and 80 °C were 119.45 h and 51.18 h, respectively, which satisfied the industrial application requirements of pullulanase.

支链淀粉酶是一种能明确切割α-1,6糖苷键的脱支酶，广泛用于淀粉糖化，葡萄糖，麦芽糖和生物乙醇的生产。耐热支链淀粉酶是从多种微生物中分离得到的。但是，缺乏支链淀粉酶的工业化生产阻碍了实验室向工业的转化。在这项研究中，用便宜的玉米淀粉和玉米浆代替了昂贵的麦芽糖浆和豆粕粉，通过改变C / N值和培养基的总能量，摇瓶中展示了440 U / mL的支链淀粉酶。随后，在50-L和50-m ^3的条件下探索培养条件生物反应器。在分批培养中，支链淀粉酶活性达到896 U / mL，而在分批补料培养中通过控制溶解氧，pH，降低糖含量和温度来提高至1743 U / mL。显着地，基于分批补料培养的技术参数，将培养体积扩大至50 m ³。支链淀粉酶的工业化生产成功，活性达到1546 U / mL。当产品在室温（25°C）下保存6个月时，支链淀粉酶活性超过90％。60和80°C的半衰期分别为119.45 h和51.18 h，满足了支链淀粉酶的工业应用要求。