Separation Of Fructooligosaccharides Research Articles

English

English

Cycle to cycle adaptive control of simulated moving bed chromatographic separation processes

The simulated moving bed (SMB) technology is increasingly applied in various fields, ranging from the food to the pharmaceutical sectors, for the chromatographic separation of fine (bio)chemicals. In this study, an adaptive controller acting on the fluid flow rates and commutation period is used to regulate the spatial location of the adsorption and desorption waves, and in turn the purity and productivity of the raffinate and extract effluents. This controller is based on a simple discrete-time model of the concentration fronts movement, derived from wave theory. A simple parameter adaptation scheme makes this controller robust to parameter uncertainties and drifts, and allows process start-up with minimum a priori knowledge of the separation parameters. In this study, the performance of the controller is demonstrated for two different applications: the separation of fructo-oligosaccharides (linear isotherms) and cyclopentanone–cycloheptanone (competitive Langmuir isotherms). Different plant/sensor configurations are also examined, indicating the potential of the control strategy even with reduced measurement information.

Evaluation of commercial resins for fructo-oligosaccharide separation

Fructo-oligosaccharides (FOS) produced by fermentative processes are obtained in mixtures containing significant amounts of salts and other non-prebiotic sugars. A demineralisation process using a mixture of a cationic and an anionic resin was proposed. The separation of FOS from a mixture of fructose, glucose and sucrose was evaluated. Experiments were conducted with several commercial cationic exchange resins in calcium, sodium and potassium forms packed in preparative columns (7cm×2.2cm length×diameter). Resins in potassium form obtained the higher retention factor values for sugars when compared to the other ionic forms. However, when compared to calcium and sodium ones, resins in potassium cationic forms were shown to be the less efficient separating sugar mixtures. The resin with best separation performance was the Diaion UBK535Ca. A recovery yield of 92% (w/w) of FOS with 90% (w/w) of purity was obtained from batch experiments conducted in a single column loaded with the Diaion UBK535Ca resin at 25°C. The temperature shown did not influence the separation performance significantly. By increasing the column length, the purity of FOS increased to 92% (w/w), however the recovery yield decreased to 88% (w/w).

Separation of complex fructo-oligosaccharides (FOS) and inulin mixtures by HPTLC-AMD

A first attempt at the separation of fructo-oligosaccharides (FOS) and inulin mixtures is presented. Preliminary results obtained by automated multiple development (AMD) of diol layers with an acetonitrile-acetone-water polarity gradient are reported. The method is very promising and highly suitable for simple, direct analysis of complex mixtures of fructo-oligosaccharides (FOS) and inulin in samples of natural origin.

Separation of fructooligosaccharides on a cation-exchange HPLC column in silver form with refractometric detection

An isocratic HPLC method was developed for the analysis of fructooligosaccharides in mixtures with sucrose, glucose and fructose. Fructooligosaccharides and sucrose were extensively hydrolyzed during the analyses at 80 °C but at 40 °C there was a negligible hydrolysis with a peak resolution over 1.5 for every pair of subsequently eluting saccharides.