Charoenlap Nisanart, Dharmsthiti Saovanee, Sirisansaneeyakul Sarote, Lertsiri Sittiwat
Department of Biotechnology, Faculty of Science, Mahidol University, Rama VI Road, Payathai, Bangkok 10400, Thailand.
Bioresour Technol. 2004 Mar;92(1):49-54. doi: 10.1016/j.biortech.2003.07.007.
Cyclodextrin (CD) is synthesized by bacterial cyclodextrin glycosyltransferase (CGTase) and is widely used in food, pharmaceutical, cosmetic, and agricultural industries. In this study, Bacillus circulans CGTase was partially purified by ammonium sulfate precipitation at 50-70% saturation. The optimum pH and temperature for CD production from sago starch were found to be in the ranges of 4.5-5.0 and 55-60 degrees C, respectively. beta-CD was the predominant product, constituting 65% of all CD products. The beta-CD produced using partially purified and crude CGTase were compared and found to have no significant difference in yield and productivity. The appropriate proportion of CGTase to sago starch for beta-CD production was determined by response surface methodology. The most appropriate enzyme:substrate ratio was 50 U g sago starch(-1) CGTase and 60 g l(-1) sago starch.
环糊精（CD）由细菌环糊精糖基转移酶（CGTase）合成，广泛应用于食品、制药、化妆品和农业行业。在本研究中，通过50 - 70%饱和度的硫酸铵沉淀对环状芽孢杆菌CGTase进行了部分纯化。发现西米淀粉生产CD的最佳pH值和温度分别在4.5 - 5.0和55 - 60摄氏度范围内。β - CD是主要产物，占所有CD产物的65%。对使用部分纯化的CGTase和粗酶生产的β - CD进行了比较，发现其产量和生产率没有显著差异。通过响应面法确定了用于β - CD生产的CGTase与西米淀粉的合适比例。最合适的酶与底物比例为50 U g西米淀粉（-1）CGTase和60 g l（-1）西米淀粉。
