Kinetics of sucrose conversion to fructo-oligosaccharides using enzyme (invertase) under free condition.

Abstract

The study reports the synthesis of fructo-oligosaccharide (FOS) from sucrose using invertase derived from Saccharomyces cerevisiae. The reaction was conducted in a batch mode under free enzyme condition. Fructo-oligosaccharide formation was detected at a high sucrose concentration of over 200g/L. The investigation was extended to study the effect of different parameters such as initial sucrose concentration (ISC), pH, and enzyme concentration. A maximum FOS yield of 10% (dry basis) was observed using 525g/L of ISC, with 6U/mL of the enzyme, and pH 5.5 at 40°C. 1-Kestose was the major product of among different forms of FOS. The FOS yield increased with an increase in sucrose concentration up to 525g/L, beyond which it started to decrease. However, the maximum FOS yield was not affected by the increasing concentration of the enzyme beyond a certain level (2U/mL). Furthermore, the activity of enzyme slightly increased with an increase in the pH up to 6, and thereafter it declined. Addition of glucose decreased the FOS yield because of enzyme inhibition. A five-step, ten-parameter model was developed, for which the simulation was performed in COPASI. The results predicted by the model were consistent with the experimental data.