PRELIMINARY SCREENING OF GLUCOSYLTRANSFERASES ENZYME FROM STREPTOCOCCUS MUTANS OF CLINICAL DENTAL CARIES SAMPLE AND INHIBITION BY USING PLANT EXTRACTS

Dental caries is a persistent disease characterized by acid damage to tooth enamel, which begins with the formation of biofilms on the tooth surface. Streptococcus mutans secretes glucosyltransferase, which enables the synthesis of extracellular glucan polymers using ingested starch within the oral cavity, ultimately resulting in acid production, a contributing factor to tooth decay. In this study, we conducted a preliminary screening and partial purification of glucosyltransferase enzymes and evaluated their inhibitory activity against selected plant extracts. We screened 36 isolates of Streptococcus mutans for glucosyltransferase enzyme production and identified the SM-18 isolate as having the highest enzyme activity and protein concentration which was selected for further study. Further enzyme optimization studies revealed that the optimal conditions for enzyme activity were pH 6.5, a temperature of 40°C, an incubation time of 18-19 hours, and a substrate concentration of 70 g/L. The extracted enzyme was precipitated at 70% using the ammonium sulphate precipitation method and had a molecular weight of approximately 65 kDa. We also analyzed the inhibitory effects of five different medicinal plant extracts on the activity of the glucosyltransferase enzyme. Our phytochemical screening revealed the presence of various constituents, including alkaloids, saponins, proteins, tannins, flavonoids, and triterpenoids, in the selected medicinal plants. Notably, some of the plant extracts showed a high percentage of inhibition against glucosyltransferase enzyme, suggesting their potential as antibacterial agents against dental caries.