[Stepwise study procedure of sugar substitutes--preliminary study with enzymes. 4. Glucosyltransferases of Streptococcus mutans AHT].

A continuous procedure for the simultaneous enzymatic measurement of the release of free fructose and glucose was adapted to the kinetic conditions of the synthesis of polysaccharides from sucrose by glucosyltransferases from Streptococcus mutans AHT. Initial velocities, Km of sucrose, and the efficiency of the formation of glucans from sucrose can be determined. Longtime incubations with the isolation of soluble and insoluble glucans as an established method were compared with the new procedure. As examples of the effect of sugar substitutes on glucosyltransferases, data on leucrose, nystose, Palatinit, xylitol, leucritol and polyglucose PL-3 are presented. The results provide a preliminary assessment of sugar substitutes such as non-cariogenic sweeteners.