Modeling and Theoretical Analysis of Isomaltooligosaccharide (IMO) Production Using Fed-Batch Process

Abstract

Isomaltooligosaccharide (IMO), a potential prebiotic, has been successfully produced in an enzymatic reaction using α-glucosidase obtained from Aspergillus niger PFS 08 and maltose as a substrate in a batch system (Basu et al. in Catal Sci Technol 5:2945–2958, 2015). The reaction mechanism was modeled using a set of experimental data and later validated against a different experimental data in the same study. In the present study, thus obtained model has been extended to a fed-batch system where in theoretical analysis has been carried out. The model simulations were carried for constant feeding, and linear feeding. Some of the simulations have resulted in higher yields in comparison to the batch experiments. It has been observed that in case of constant feeding, i.e., feeding at a constant flowrate throughout the fed-batch, with flow rate of 0.005 L/h and above value has improved the yield of IMO significantly. The yield of IMO (g IMO/g maltose) for batch experiment was 0.38 at the end of 60 h (Basu et al. in Catal Sci Technol 5:2945–2958, 2015), whereas at flow-rates ≥0.005 L/h the yield of IMO ranged between 0.50 and 0.53 at the end of 60 h. Similarly, in case of linear feeding, where in the feed was a linear function of time, the yields in IMO increased significantly. Here in linear feeding, different incremental slopes, ranging 2 × 10−5 to 2 × 10−1 L/h2 were selected to dose the maltose in separate simulations, and it was observed that the yields of IMO ranged between 0.42 and 0.58 in case of 60 h of fed-batch reaction. Using both constant and linear feeding profiles, simulations were again carried for a time period of 24 h as the yield of IMO in the batch reaction was maximum at the end of 24 h. From these simulation results, the yields observed were greater than 0.6. Finally from this theoretical study it could be concluded that higher yields and productivity can be achieved in the fed-batch process of IMO production in comparison to batch setup.