Optimization of Enzymatic Synthesis of Isomalto-Oligosaccharides Production

Abstract

Glucosyltransferases can be applied in the synthesis of prebiotic oligosaccharides. Enzymatic synthesis using acceptors can be used to obtain these carbohydrates. When maltose is the acceptor, oligosaccharides containing one maltose moiety and up to eight glucose units linked by a-1,6glycosidic bonds are obtained as the product of dextransucrase acceptor reaction. In this work, the enzymatic synthesis of isomalto-oligosaccharides using dextransucrase from Leuconostoc mesenteroides NRRL B-512F was optimized by response surface methodology. The effect of maltose and sucrose concentrations on the acceptor reaction was evaluated in a batch reactor system. Partially purified enzyme was used to reduce the enzyme purification cost. The results showed that high sucrose concentrations in conjunction with high maltose levels enhanced the isomalto-oligosaccharide synthesis. A productivity of 42.95 mmol/L.h of isomalto-oligosaccharides was obtained at the optimal operating condition (100 mmol/L of sucrose and 200 mmol/L of maltose).j fbc_222 342..354 CorrespondingOligosaccharides as prebiotic have a large application in food formulations, and their beneficial role in human health have been extensively studied. Although the acceptor mechanism of dextransucrase has already been extensively studied, an industrial process has not been developed yet for enzyme synthesis of isomalto-oligosaccharide. The process studied in this work allows the large-scale preparation of isomalto-oligosaccharide using partially purified enzyme. ENZYMATIC SYNTHESIS OF ISOMALTO-OLIGOSACCHARIDES 344M.C. RABELO ET AL.

Development of low caloric prebiotic fruit juices by dexransucrase acceptor reaction

“…The linear effects of sucrose and reducing sugars were positive and significant for oligosaccharide synthesis. A similar result was obtained by Rabelo et al (2009b) for prebiotic cashew apple juice obtained by fermentation with L. mesenteroides B-512 F. The positive and significant linear effect means that increasing the substrate concentration the oligosaccharide formation is increased. On the other hand, the quadratic effects and the interaction between sucrose and reducing sugar were not significant on the oligosaccharide formation.…”

“…Although the enzyme synthesis was target to oligosaccharides formation, the acceptor reactor is a side reaction of dextran formation and the strategy applied in the present study was enough to shift the enzyme pathway from dextran synthesis to the acceptor reaction because the dextran formed was low compared to the oligosaccharide formation. Rabelo et al(2009b) observed that dextran formation was favored when high concentrations of sucrose and low concentration of reducing sugars was applied. In fact, a low amount of dextran might be beneficial for the final product because dextran is a polysaccharide applied as food thickener that can increase the beverage viscosity (Kassai 2012).…”

Structural features underlying prebiotic activity of conventional and potential prebiotic oligosaccharides in food and health

“…The high selectivity and specificity of glucansucrases compared to chemical approaches make them useful synthetic tools for the production of high‐value carbohydrate‐based prebiotics. Optimization studies are underway to economically utilize microbes to maximize enzyme output (Purama & Goyal, ), as well as the enzymes to maximize the generation of OSs (Rabelo, Honorato, Gonçalves, Pinto, & Rodrigues, ). Gluco‐oligosaccharides (GOS) are prepared with the help of glucosyl‐transferases (Dextransucrase (EC 2.4.1.5) and alternansucrase (EC 2.4.1.140) derived from Leuconostoc mesenteroides NRRL B‐512F, which transfer glucose moieties from sucrose to other acceptors (Côté, ; Sanz, Côté, Gibson, & Rastall, ).…”

“…The high selectivity and specificity of glucansucrases compared to chemical approaches make them useful synthetic tools for the production of high-value carbohydrate-based prebiotics. Optimization studies are underway to economically utilize microbes to maximize enzyme output (Purama & Goyal, 2009), as well as the enzymes to maximize the generation of OSs (Rabelo, Honorato, Gonçalves, Pinto, & Rodrigues, 2009 . However, no significant levels of growth was observed in lactic acid bacteria, Bacteroides, Atopobium cluster, and…”

Microbial Glycosidases for Nondigestible Oligosaccharides Production

“…immobilized on epoxy produced IMOs (DPs 8-10) from dextran T40 in an enzymatic reactor [68]. A productivity of 42.95 mmol/L.h was obtained using 100 mmol/L of sucrose and 200 mmol/L of maltose, using dextransucrase (1 U/mL) from Leuconostoc mesenteroides NRRL B-512F [69]. A productivity of 7.26 mmol/L.h of IMOs was obtained a using an immobilized mixture of dextransucrase and dextranase [70], while a purified dextransucrase yielded 35 mmol/L.h of panose [71].…”