ANTI-CARIOGENIC POTENTIALS OF VITEX NEGUNDO LINN

Abstract

Vitex negundo Linn. (Verbenaceae), is an ethnobotanical important shrub carrying a large array of pharmacologically active phytochemicals with diverse medicinal properties. Present study assessed the antibacterial activities of leaf and twig (without leaf) bioactives against common oral bacterial inhabitants viz., Staphylococcus aureus, Streptococcus oralis, Streptococcus gordonii, Streptococcus mutans, Lactobacillus brevis and Lactobacillus casei. Leaf and twig dried powdered samples of V. negundo were separately fractionated by five solvents in eluotropic series namely petroleum-ether, chloroform, absolute-ethanol, 80%-methanol and distilled-water. Extracts were further analyzed for total phenolic contents (TPC), flavonoids (TFC), tannins, alkaloids and terpenoids. Zone of inhibition, MIC, MBC and IC50 values of the fractionated extracts against oral bacterial pathogens were determined. The results demonstrated significantly higher antibacterial activity in ethanolic extracts (VnLEt) and chloroform (VnLCh) extracts of leaves as evident by their higher ZOI and lower MIC, MBC and IC50 values. VnLEt extracts showed bactericidal effects against all the tested six bacterial pathogens (L. casei>St. gordonii>Staphylococcus aureus>L. brevis>St. oralis=St. mutans). VnLCh showed notable bactericidal effects against five pathogens (L. casei>St. mutans>St. gordonii>Staphylococcus aureus) but remained ineffective against St. oralis and L. brevis. Among twig extracts, ethanolic extracts showed inhibition against Staphylococcus aureus, St. gordonii and St. mutans while chloroform extracts showed antibacterial effect only against Staphylococcus aureus. VnLEt extract showed abundance in TPC, TFC and tannins while VnLCh was rich in alkaloids and terpenoid suggesting their contribution in bactericidal effects against cariogenic bacterial pathogens. Hence, the present study successfully established V. negundo leaf extracts as an excellent natural remedy for oral-dental infections.