Antimicrobial activities of Garcinia kola seeds extracts on dental caries-causing microorganisms
Garcinia kola Heckel seeds (Family Guttiferae) also known as African wonder nut or bitter cola find use in folkloric medicine in Southern Nigeria for the treatment of tooth ache and prevention of dental caries . We have examined the effect of the crude ethanolic extract and chromatographic fractions of this Nigeria edible seed against clinical isolates of dental caries-causing microorganisms-Streptococcus mutans and Streptococcus viridans. The cup plate method using blood agar as well as broth dilution methods was employed in the antimicrobial assay. Of the six pooled vacuum liquid chromatographic (VLC) fractions examined, fraction N (hexane: ethylacetate 70: 30) exhibited the highest activity with MIC's of 1.50mg ml-1 and 0.33mg ml-1 against S.mutans and S.viridans respectively. Corresponding MIC's for gentamicin reference standard was found to be 0.04µg ml-1 and 0.13µg ml-1. Thin-layer chromatographic screening showed that the major constituents of Fraction N are flavonoid related compounds which also showed free radical scavenging activity when sprayed with 2,2 diphenyl-1-picrylhydrazil (DPPH) radical.
The results provide some justifications for the use of G .kola in traditional medicine for dental caries related health problems.
Acknowledgements:This work was supported by University of Ibadan Senate Research Grant SRG/COM/2006/1A
References: 1. Irvine FR (1961) Woody Plants of Ghana. Oxford Press. P. 58.