This study was undertaken to determine if extracts from some sorts of chewing gum containing mutastein, a potent glucosyltransferase (GTase) inhibitor, have an inhibitory effect on insoluble glucan synthesis by Streptococcus mutans (S. mutans) and cellular adherence to glass. Six extracts from sucrose chewing gum and two sorts of palatinose chewing gum with or without mutastein were prepared and two S. mutans strains were cultivated in the BHI medium containing each extract. Similar experiments were also carried out using crude GTase of S. mutans 6715. Then adhesive and nonadhesive glucan products and growing cells adhering to glass in the six test mediums were determined.
It was found that insoluble glucan product, especially in adhesive glucan, and adhesive growing cells were fewer in the three mediums containing mutastein than in those without mutastein, although no obvious difference between S. mutans 6715 and B 13 was seen in the measured value. Similar results for insoluble glucan product were obtained in the experiment using crude GTase. In the experiment of in vitro plaque formation, fewer adhesive glucan and cells covered a glass rod in the medium with mutastein than in the medium without mutastein.
These results indicated that mutastein in chewing gum has a distinctly inhibitory effect on insoluble glucan synthesis and growing cells. It can be concluded from these in vitro studies that chewing of sucrose gum containing mutastein could lower dental caries due to sugar in the gum and also that palatinose gum with mutastein could prevent dental caries due to concomitant sugared foods by decreasing dental plaque formation in vivo.
