Miao Ming, Jiang Bo, Jin Zhengyu, BeMiller James N
State Key Laboratory of Food Science & Technology, Jiangnan Univ., 1800 Lihu Ave., Wuxi, Jiangsu, 214122, P. R. China.
Dept. of Food Science, Whistler Center for Carbohydrate Research, Purdue Univ., 745 Agriculture Mall Drive, West Lafayette, IN, 47907-2009, U.S.A.
Compr Rev Food Sci Food Saf. 2018 Sep;17(5):1238-1260. doi: 10.1111/1541-4337.12381. Epub 2018 Aug 3.
Starch is an abundant, natural, renewable resource, and present as the major storage carbohydrate in the seeds, roots, or tubers of many important food crops, such as maize, wheat, rice, potato, and cassava. Uses of native starches in most industrial applications are limited by their inherent properties. Hence, they are often structurally modified after isolation to enhance desirable attributes, to minimize undesirable attributes, or to create new attributes. Enzymatic, rather than chemical, approaches are used in the production of starch syrups, maltodextrins, and cyclodextrins. However, the desire for starch-active enzymes working optimally at high temperatures and low pH conditions with superior stability and activity is still not satisfied and this stimulates interest in developing novel and improved starch-active enzymes through a variety of strategies. This review provides current information on enzymes belonging to GH13, 57, 70, and 77 that can be used in structural modifications of the starch polysaccharides or to produce starch-derived products from them. The characteristics and catalytic mechanisms of microbial enzymes are discussed (including 4-α-glucanotransferase, branching enzyme, maltogenic amylase, cyclomaltodextrinase, amylosucrase, and glucansucrase). Product diversity after starch-converting reaction and utilization in industrial applications are also dealt with.
淀粉是一种丰富、天然、可再生的资源，是许多重要粮食作物种子、根或块茎中的主要储存碳水化合物，如玉米、小麦、水稻、马铃薯和木薯。天然淀粉在大多数工业应用中的使用受到其固有特性的限制。因此，它们在分离后通常会进行结构改性，以增强所需特性、最小化不良特性或创造新特性。在淀粉糖浆、麦芽糊精和环糊精的生产中使用的是酶法而非化学法。然而，人们对在高温和低pH条件下具有最佳活性且稳定性和活性优异的淀粉活性酶的需求仍未得到满足，这激发了人们通过各种策略开发新型和改良淀粉活性酶的兴趣。本综述提供了有关属于GH13、57、70和77家族的酶的当前信息，这些酶可用于淀粉多糖的结构修饰或从淀粉多糖生产淀粉衍生产品。讨论了微生物酶的特性和催化机制（包括4-α-葡聚糖转移酶、分支酶、产麦芽淀粉酶、环麦芽糊精酶、淀粉蔗糖酶和葡聚糖蔗糖酶）。还探讨了淀粉转化反应后的产物多样性及其在工业应用中的利用。
