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A process for industrial production of fructooligosaccharides (FOS’s) based on the conversion of sucrose by immobilized fructosyltransferase (FTase) from the cells of Aureobasidium pullulans CCY 27-1-94 was developed. Particular process operations and conditions were designed employing results of laboratory and semi-pilot scale experiments. The process flowsheet comprised three sections: FTase production, which included fermentation, isolation and purification of the enzyme, FTase immobilization and FOS’s production where a product with a high content of FOS’s was prepared by the removal of glucose, fructose and unreacted sucrose from the reaction mixture using simulated moving-bed chromatography. Two alternative process flowsheets were proposed for the annual production of 10 000 t of FOS’s: one for a powdery product and the second one for syrup. The economic analysis provided the costs for the production of immobilized FTase and FOS’s using two different price estimates for sucrose.

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The adsorption equilibria relevant to the production of fructooligosaccharides were measured on Dowex Monosphere 99CA/320, Amberlite CR1320Ca, Lewatit S 2568, and Diaion UBK 530. The single-component isotherms of glucose, fructose, and sucrose and multicomponent isotherms of fructooligosaccharides (kestose, nystose, and fructofuranosylnystose) were obtained at a temperature of 60 °C and saccharide concentrations up to about 450 g·L-1. All but sucrose equilibrium data were described with a linear isotherm. The adsorption data of sucrose were successfully fitted using a concave isotherm. The capacities and selectivities of the adsorbents were compared. They showed that their separation effect was based on the size exclusion mechanism accompanied by complexation, which depended significantly on the resin's ionic form.

Viable microbial cells are important biocatalysts in the production of fine chemicals and biofuels, in environmental applications and also in emerging applications such as biosensors or medicine. Their increasing significance is driven mainly by the intensive development of high performance recombinant strains supplying multienzyme cascade reaction pathways, and by advances in preservation of the native state and stability of whole-cell biocatalysts throughout their application. In many cases, the stability and performance of whole-cell biocatalysts can be highly improved by controlled immobilization techniques. This review summarizes the current progress in the development of immobilized whole-cell biocatalysts, the immobilization methods as well as in the bioreaction engineering aspects and economical aspects of their biocatalytic applications.