RESUMO
CONTEXT: Essential oils are prevalent in many medicinal plants used for oral hygiene and treatment of diseases. OBJECTIVE: Medicinal plant species were extracted to determine the essential oil content. Those producing sufficient oil were screened for activity against Staphylococcus aureus, Escherichia coli, Streptococcus mutans, Lactobacillus acidophilus, and Candida albicans. MATERIALS AND METHODS: Plant samples were collected, frozen, and essential oils were extracted by steam distillation. Minimum inhibitory concentrations (MIC) were determined using a tube dilution assay for those species yielding sufficient oil. RESULTS: Fifty-nine of the 141 plant species produced sufficient oil for collection and 12 species not previously reported to produce essential oils were identified. Essential oil extracts from 32 species exhibited activity against one or more microbes. Oils from eight species were highly inhibitory to S. mutans, four species were highly inhibitory to C. albicans, and 19 species yielded MIC values less than the reference drugs. DISCUSSION: RESULTS suggest that 11 species were highly inhibitory to the microbes tested and merit further investigation. Oils from Cinnamomum zeylanicum Blume (Lauraceae), Citrus aurantiifolia (Christm.) Swingle (Rutaceae), Lippia graveolens Kunth (Verbenaceae), and Origanum vulgare L. (Lamiaceae) yielded highly significant or moderate activity against all microbes and have potential as antimicrobial agents. CONCLUSION: Teas prepared by decoction or infusion are known methods for extracting essential oils. Oils from 11 species were highly active against the microbes tested and merit investigation as to their potential for addressing health-related issues and in oral hygiene.
Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Óleos Voláteis/farmacologia , Plantas Medicinais/química , Antibacterianos/isolamento & purificação , Antifúngicos/isolamento & purificação , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Guatemala , Testes de Sensibilidade Microbiana , Óleos Voláteis/isolamento & purificação , Plantas Medicinais/crescimento & desenvolvimento , Especificidade da EspécieRESUMO
CONTEXT: Thirty-one medicinal plant species from Hawaii, Morocco, and the Sonoran Desert, USA have been shown in past studies to be highly inhibitory to pathogenic bacteria, fungi, and certain cancer cell lines. However, none were tested for antiviral activity. OBJECTIVE: Acetone and methanol extracts from these species were bio-assayed for antiviral activity against herpes simplex virus types 1 and 2, and for cytotoxicity to the Vero C1008 cell line. MATERIALS AND METHODS: Extracts from these species were tested in vitro for antiviral activity using an immunoperoxidase mini-plaque reduction assay to detect viral structural protein synthesis. A 50% inhibitory concentration (IC(50)) was computed. Sulforhodamine B and neutral red assays were used to qualitatively and quantitatively assess the cytotoxicity of extracts to C1008 cells, and to compute a 50% cytotoxic concentration (CC(50)) using a dose response curve. RESULTS: Eight of the 31 plant species assayed showed significant antiviral activity against HSV 1 and HSV 2 viruses. The acetone extract of Kalanchoe pinnata Pers. (Crassulaceae) produced an IC(50) of 0.025 mg/mL and a CC(50) of 1.25 mg/mL yielding a therapeutic index of 50. Additionally, this extract reduced plaque numbers to zero or near zero at a concentration of 0.1 mg/mL when added 30 min before or 30 min after virus infection. DISCUSSION AND CONCLUSION: The mechanism of inhibition against HSV 1 and HSV 2 viruses is now being investigated, along with fractionation of the acetone extract in search of the active compound or compounds.