Identification of glucosyl transferase inhibitors from Psidium guajava against Streptococcus mutans in dental caries.

Dental caries is a multi factorial disease that starts with microbiological shifts affected by salivary flow, composition, exposure to fluoride, consumption of dietary sugars, and preventive behaviours. The Streptococcus mutans (S. mutans) is an initiator of caries because there is a variety of a virulence factor unique to the bacterium that has been isolated and plays an important role in caries formation. The aim of the present study is to identify the beneficial effect of bioactive compounds in Psidium guajava (P. guajava) and its inhibitory role against S. mutans in dental caries. The methanolic extract was used for analysis of GC-MS for the identification of bioactive compounds. The results confirm the existence of 7 different compounds. The identified bioactive compounds were corynan-17-ol, 18,19-didehydro-10-methyoxy-acetate, Copaene, 3Bicyclo(5.2.0)nonane, 2-methylene-4,8,8-trimethyl-4-vinyl,Azulene,1,2,3a,4,5,6,7-octahydro-1,4-dimethyl-7-methylethenyl) [1R- (1a,3aa',4a',7a')], α-Caryophyllene, Alloaromadendrene oxide-(1) and Androstan-17-one, 3-ethyl-3-hydroxy-, (5a). The saliva of dental caries during and after treatment of aqueous leaf extract was used for the analysis of bacterial load and determining the activity of Glucosyl transferase (GTF). The result obtained at different time intervals, showed significant decrease (P < 0.01) in the bacterial load of saliva on P. guajava treatment. The molecular docking studies identified the interaction between GTF and the bioactive compounds of P. guajava. The anticariogenic active compounds interacted through active sites of sucrose and inhibit the formation of glucan. The study suggested that it could be maximized the anticariogenic effect of the selected medicinal plant, and further focus is needed to identify the combined plant extract to explore the additional protection against dental caries.