earticle

영어

Maltodextrin in specific length is of great interest because of its wide industrial applications. Previously, we have proven that Pyrococcus furiosus thermostable amylase (PFTA) produces high purity maltoheptaose (G7) from β-cyclodextrin (CD) at early reaction time. However, the production of pure G7 is a cost and time-consuming process. Therefore, this work has designed an optimal continuous process for pure G7 production from β-CD using PFTA with immobilization in a packed-bed reactor (PBR). The optimal conditions determined using the response surface method for the maximized G7-purity of 96.3% were predicted at 4.7 ml/min of flow rate, 1.1% substrate, and 48.7 °C. As a result, the immobilized PFTA in PBR retained 85% of the initial activity after six cycles of 24 h intervals, and the product purity was unchanged. Also, maltohexaose (G6) and maltooctaose (G8) at high purity (92-97%) were produced by continuously supplying CDs to the PFTA-PBR under the same optimized condition of G7. In addition, a new method based on preparative reversed-phase liquid chromatography was developed to purify maltodextrins in specific lengths (DP 3-26) with high purity from the reaction mixture of G6-G8 substrates with Thermotoga maritima maltosyltransferase. On the other hand, novel G7-based sugar esters were also synthesized and investigated for emulsifying properties. As a result, G7-fatty acids (C10–C16) esters were produced with a high conversion yield (90-95%) under the optimal conditions (10% of DMSO, 0.2 of G7/ fatty acids molar ratio, 33.5 U of immobilized Candida antarctica lipase B) for 24 h of incubation at 60 °C. Notable, G7-palmitate (PA) exhibited emulsifying properties better than commercial sucrose-PA ester, especially in acidic conditions. It is feasible that the number of the hydroxyl groups and the size of G7 moiety provide that distinctive property of G7-PA. Therefore, applications of G7-PA in foods, cosmetics, and drug delivery under extreme pH conditions are promising.