RESUMO
CONTEXT: Lippia thymoides Mart. & Schauer (Verbenaceae) is used in folk medicine to treat wounds, fever, bronchitis, rheumatism, headaches, and weakness. OBJECTIVE: This study determinates the chemical composition of essential oils from L. thymoides, obtained at during each of the four seasons and correlates with pharmacological properties. MATERIALS AND METHODS: Essential oils were obtained by hydrodistillation and analyzed by gas chromatography coupled to mass spectroscopy (GC-MS). Antioxidant activity was determined by DPPH free radical scavenging and ß-carotene bleaching methods. The antimicrobial assays were performed by minimum inhibitory concentration (MIC) and minimum microbicidal concentration (MMC) methods. Isolated rat aorta and uterus, and guinea-pig trachea were utilized to evaluate relaxant potential in pre-contracted smooth muscle. RESULTS AND DISCUSSION: Essential oils from leaves of L. thymoides had the sesquiterpene ß-caryophyllene (17.22-26.27%) as the major constituent followed by borneol (4.45-7.36%), camphor (3.22-8.61%), camphene (2.64-5.66%), and germacrene D (4.72-6.18%). In vitro assays showed that these essential oils do not have antioxidant activity, have antimicrobial selectivity to Gram-positive bacteria Staphylococcus aureus (MIC = 0.004 mg/mL and MMC = 0.26-10.19 mg/mL) and Micrococcus luteus (MIC = 0.03 mg/mL and MMC = 8.43 mg/mL), relax isolated rat aorta (EC50 = 305-544 µg/mL, with endothelium; and EC50 = 150-283 µg/mL, without endothelium), and uterus (EC50 = 74-257 µg/mL), and minor potency, isolated guinea-pig trachea. CONCLUSIONS: Lippia thymoides is a source of natural products of pharmaceutical interest, being necessary additional studies to determine the substances involved in the biological activities.
Assuntos
Lippia/química , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Óleos de Plantas/farmacologia , Estações do Ano , Resistência das Vias Respiratórias/efeitos dos fármacos , Animais , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/fisiologia , Compostos de Bifenilo/química , Relação Dose-Resposta a Droga , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Cobaias , Masculino , Testes de Sensibilidade Microbiana , Micrococcus luteus/efeitos dos fármacos , Micrococcus luteus/crescimento & desenvolvimento , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Oxirredução , Fitoterapia , Picratos/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta , Óleos de Plantas/química , Óleos de Plantas/isolamento & purificação , Plantas Medicinais , Ratos Wistar , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Tocolíticos/química , Tocolíticos/isolamento & purificação , Tocolíticos/farmacologia , Traqueia/efeitos dos fármacos , Traqueia/fisiologia , Contração Uterina/efeitos dos fármacos , Útero/efeitos dos fármacos , Útero/fisiologia , Vasodilatação/efeitos dos fármacos , Vasodilatadores/química , Vasodilatadores/isolamento & purificação , Vasodilatadores/farmacologia , beta Caroteno/químicaRESUMO
Lippia origanoides Kunth, Lippia alnifolia Schauer, and Lippia thymoides Martius and Schauer are shrubs used in the traditional Brazilian medicine as antiseptics, as well as in the treatment of infectious diseases. This study was designed to investigate the antibacterial and antifungal activities of the methanolic extracts of these species, as new potential sources of antimicrobial drugs. The antimicrobial activity of methanolic extracts was investigated against resistant yeasts and bacteria by agar disk diffusion. Then, the MIC determination of the most active species and its fractions in hexane, dichloromethane, ethyl acetate, and water was performed. By the agar diffusion assay, all species were active against at least two microorganisms, giving evidence to support their use in the popular medicine. L. origanoides leaves exhibited the widest antimicrobial action, inhibiting the growth of two Gram-positive bacteria and two yeasts; this activity was also confirmed by the MIC evaluation. The fractionation of L. origanoides crude extracts improved the activity in spectrum and intensity. The results obtained in this study indicate that L. origanoides may be a promising alternative in the treatment of bacterial and fungal infections and in the seeking of new antimicrobial drugs.
RESUMO
Este trabalho apresenta o estudo morfoanatômico das folhas e caules de Microlicia hatschbachii Wurdack, Melastomataceae. Esta espécie possui folhas elípticas a oval-elípticas, margem inteira, ápice agudo e base simétrica e arredondada. A lâmina foliar é anfiestomática, com estômatos do tipo anisocítico e anomocítico, a epiderme é uniestratificada, com células isodiamétricas em secção transversal, e presença de inúmeros tricomas glandulares. O mesofilo é do tipo isobilateral com feixe vascular bicolateral envolvido por algumas células esclerenquimáticas na nervura central. O caule tem secção quadrangular a circular e epiderme unisseriada, com tricomas similares aos da folha. Drusas de oxalato de cálcio foram encontradas nas folhas e no caule.
This work shows the morpho-anatomical study of leaf and stem of Microlicia hatschbachii Wurdack (Melastomataceae). Its leaves are elliptic to oval-elliptic, with entire margin, acute apex and rounded symmetrical base. The leaf blade is amphistomatical with anisocytic and anomocytic stomata, in transection the epidermis is uniseriate with isodiametric cells and presence of several glandular trichomes. The mesophyll is isobilateral with bicollateral vascular bundles surrounded by some sclerenchymatic cells in midrib. The stem has a quadrangular to circular transection and uniseriate epidermis with trichomes like ones of leaf. Several druses of calcium oxalate are found in the leaf and stem.