title: Antimicrobial activity of medicinal plants against oral microorganisms.
abstract: Ethanol extracts of eight plant species used traditionally in South Africa for the treatment of oral diseases were investigated for in vitro antimicrobial activity against oral pathogens namely Actinobacillus actinomycetemcomitans, Actinomyces naeslundii, Actinomyces israelii, Candida albicans, Porphyromonus gingivalis, Privotella intermedia and Streptococcus mutans using the disk diffusion method. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of ethanol extracts were determined against these microorganisms using micro dilution. The cytotoxicity and therapeutic index (TI) of selected active extracts were also determined. Out of eight plants, six (Annona senegalensis, Englerophytum magalismontanum, Dicerocarym senecioides, Euclea divinorum, Euclea natalensis, Solanum panduriforme and Parinari curatellifolia) exhibited MIC values ranging from 25.0 mg/ml to 0.8 mg/ml. Gram negative bacteria were found to be more resistant to the plant extracts than Gram positive bacteria, except for Euclea natalensis which inhibited all three Gram negative bacteria tested in this study. All plant extracts showed moderate cytotoxicity on the Vero cell line. The fifty percent inhibitory concentration (IC(50)) of all plants tested range from 92.3 to 285.1 microg/ml.
authors.affiliation: Department of Plant Science, University of Pretoria, Pretoria 0002, South Africa.
authors.forename: G
authors.initials: G
authors.lastname: More
authors.forename: T E
authors.initials: TE
authors.lastname: Tshikalange
authors.forename: N
authors.initials: N
authors.lastname: Lall
authors.forename: F
authors.initials: F
authors.lastname: Botha
authors.forename: J J M
authors.initials: JJ
authors.lastname: Meyer
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000302:isolation & purification / Q000494:pharmacology*; D000891:Anti-Infective Agents, Local / Q000494:pharmacology; D002470:Cell Survival / Q000187:drug effects; D002710:Chlorhexidine / Q000494:pharmacology; D002522:Chlorocebus aethiops; D003731:Dental Caries / Q000382:microbiology; D005891:Gingivitis / Q000382:microbiology; D006801:Humans; D016488:Medicine, African Traditional; D008826:Microbial Sensitivity Tests; D009055:Mouth / Q000382:microbiology*; D010518:Periodontitis / Q000382:microbiology; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology; D010946:Plants, Medicinal / Q000737:chemistry*; D013019:South Africa; D014709:Vero Cells
chemical_list: D000890:Anti-Infective Agents; D000891:Anti-Infective Agents, Local; D010936:Plant Extracts; D002710:Chlorhexidine