THE EFFECT OF FRUCTOSE ON THE METABOLISM OF SUCROSE BY STREPTOCOCCUS MUTANS

Statement of problem: Streptococcus produces energy and forms extracellular polysaccharides by metabolizing sucrose. Insoluble glucan, a kind of extracellular polysaccharide, is the important material of dental plaque. Fructose affects the metabolism of sucrose. Purpose: The purpose of this study was to evaluate the effect of fructose on the metabolism of sucrose in Streptococcus mutans. Materials and methods: To determine the effect of fructose on the formation of artificial plaque by Streptococcus mutans Ingbritt, S. mutans and fructose were placed in beakers containing M17 broth and sucrose. The wires were hung on frameworks inserted into cork stoppers, and then immersed in each of the beakers. After the incubation with gentle shaking, each wire was weighed. To analyze the effect of fructose on the sucrose metabolism by S. mutans or glucosyltransferase, S. mutans and fructose were placed in M17 broth containing sucrose. After the incubation. the remaining sucrose and polymers were analysed by thin layer chromatography. Results: The following results were obtained; 1. When Streptococcus mutans was cultured in the media containing 3% sucrose for 8 hours, the mean weight of formed artificial plaque on the wires was , whereas being reduced to in the media added with 3% sucrose and 4% fructose(p