RESUMO
BACKGROUND: The global resurgence of tuberculosis (TB) and the development of drug resistance, as multidrug-resistant (MDR) and extensively drug-resistant (XDR) Mycobacterium tuberculosis isolates, are a threat to TB control and have created a need for new and more effective anti-TB drugs. AIM: The current study evaluated the in vitro cytotoxicity and activity of Tetradenia riparia essential oil (TrEO) and 6,7-dehydroroyleanone pure compound against M. tuberculosis H37Rv and susceptible and resistant clinical isolates. METHODS: The in vitro activities of TrEO and 6,7-dehydroroyleanone were determined by Resazurin Microtiter Assay Plate (REMA). The cytotoxicity was evaluated in murine peritoneal macrophages by Alamar Blue assay. The cytotoxic effects were expressed as median concentration cytotoxicity (CC50) and the selectivity index (SI) was calculated. RESULTS: TrEO and 6,7-dehydroroyleanone showed activity against M. tuberculosis H37Rv with minimum inhibitory concentration (MIC) 62.5⯵g/ml and 31.2⯵g/ml, respectively. Both of them exhibited activities against resistant and susceptible M. tuberculosis clinical isolates with MIC values between 31.2 and 62.5⯵g/ml. Cytotoxicity assays showed SI 1.9 and 7.9 for TrEO and 6,7-dehydroroyleanone, respectively. CONCLUSION: These results revealed that TrEO isolated from leaves of T. riparia and the pure compound 6,7-dehydroroyleanone display good activity against M. tuberculosis clinical isolates, including MDR isolates, with low cytotoxicity to murine macrophages. The 6,7-dehydroroyleanone compound is a potential candidate for anti-TB drug.
Assuntos
Abietanos/farmacologia , Antituberculosos/farmacologia , Lamiaceae/química , Mycobacterium tuberculosis/efeitos dos fármacos , Óleos Voláteis/farmacologia , Animais , Células Cultivadas , Macrófagos Peritoneais/efeitos dos fármacos , Camundongos , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia , Folhas de Planta/química , Óleos de Plantas/farmacologiaRESUMO
Tetradenia riparia (Hochst.) Codd (Lamiaceae) is a shrub, commonly known as ginger bush or false myrrh, and several studies have shown that T. riparia exhibits a variety of biological properties. This study aimed to determine the chemical composition of T. riparia essential oil and its fractions, investigate their anticholinesterase activity, and assess their larvicidal activity against the cattle tick Rhipicephalus microplus and the mosquito Aedes aegypti. Eleven essential oil fractions were obtained by fractionation and analyzed by gas chromatography/mass spectrometry. Larvicidal activity against R. microplus and third-instar A. aegypti was assessed using a larval packet test and a larval immersion test, respectively. Anticholinesterase activity was determined by a bioautographic method. Forty-nine compounds were identified in the essential oil, of which the major classes were oxygenated sesquiterpenes (45.95%) and sesquiterpene hydrocarbons (35.20%) and the major components were isospathulenol (17.40%), ß-caryophyllene (15.61%), 14-hydroxy-9-epi-caryophyllene (10.07%), 14-hydroxy-α-muurolene (8.32%), and 9ß,13ß-epoxy-7-abietene (5.53%). Bioassays showed that T. riparia essential oil (LC50 = 1.56 µg/mL) and FR3 (LC50 = 0.30 µg/mL) were the most active against R. microplus and A. aegypti larvae, respectively. The essential oil and FR1, FR2, and FR3 exhibited acetylcholinesterase inhibitory activity. These results indicate that T. riparia essential oil and its fractions hold promise in the development of novel, environmentally safe agents for the control of R. microplus and A. aegypti larvae.
Assuntos
Carrapatos , Aedes , Lamiaceae/toxicidade , Lamiaceae/química , LarvicidasRESUMO
Própolis é uma substância resinosa obtida pelas abelhas de diversas partes da planta e vem sendo utilizada desde a antiguidade devido seu amplo espectro de atividade biológica. A infestação em animais de grande porte por Rhipicephalus (Boophilus) microplus é uma problemática nos dias atuais, em que se utiliza para sua eliminação medicamentos que causam a contaminação do animal, e dos seus subprodutos. O presente trabalho teve por objetivo avaliar in vitro a atividade do extratoalcoólico da própolis no combate ao carrapato da espécie Rhipicephalus (Boophilus) microplus em vacas leiteiras da raça holandesa pertencentes a uma propriedade rural no município de Icaraíma- Paraná. O experimento foi inteiramente casualisado, os testes consistiram na comparação da postura e eclosão dos ovos de animais tratados com extrato alcoólico de própolis nas concentrações de 50%, 25%, 12,5% e 6,25%, no qual a concentração de 50% foi a mais eficiente, obtendo uma margem de 99,10% de eficácia; enquanto as concentrações de 25%, 12,5% e 6,25%, obtiveram uma eficácia de 73,53%, 77,07% e 50,93% respectivamente. Os resultados mostraram uma maior sensibilidade dos carrapatos à concentrações mais elevadas. A própolis pode ser uma opção de tratamento, podendo ser utilizado como uma fonte para atividade carrapaticida devido às suas inúmeras substâncias funcionais.
Propolis is a resinous substance obtained by bees from several parts of the plants and it has been used since ancient times due to its broad biological activity spectrum. Large-sized animals infested with Rhipicephalus (Boophilus) microplus are nowadays considered a problem, and in order to eliminate the infestation, medicines and byproducts are used, which can cause animal contamination. The present study has the purpose of evaluating the in vitro activity of the alcohol extract in propolis in combating ticks from Rhipicephalus (Boophilus) microplus species in Holstein cows belonging to a small farm in Icaraima- Paraná. The experiment was completely randomized, the assays consisted in the comparison of the laying and hatching of eggs in animals treated with the alcoholic extract from propolis in the concentrations of 50%, 25%,12. 5% and 6.25%. The concentration of 50% was the most efficient, yielding a margin of 99.10% efficiency. Meanwhile, the concentrations of 25%, 12,5% and 6.25%, had an efficiency of 73.53%, 77.07% and 50.93%, respectively. The results showed a greater sensitivity of ticks to the higher concentrations. Propolis, therefore, can be an treatment option, and can be used as a source of acaricide activity because of its several functional substances.
Propóleos es una sustancia resinosa obtenida por las abejas a partir de diferentes partes de la planta y se ha utilizado desde la antigüedad debido a su amplio espectro de actividad biológica. La infestación en animales de gran porte por Rhipicephalus (Boophilus) microplus es un problema hoy en día, porque el tratamiento consiste en el uso de medicamentos que causan la contaminación del animal, y de sus derivados. Este estudio tuvo como objetivo evaluar la actividad in vitro del extracto alcohólico de propóleos para combatir la especie de garrapata Rhipicephalus (Boophilus) microplus en vacas lecheras de la raza holandesa pertenecientes e una propiedad rural en el municipio de Icaraíma-Paraná. El experimento fue totalmente aleatorizado, pruebas consistieron en la comparación de la postura y eclosión de los huevos de animales tratados con extracto alcohólico de propóleos en concentraciones de 50%, 25%, 12. 5% y 6,25%, donde la concentración de 50% fue la más eficiente, obteniendo un margen de 99,10% de eficacia; mientras que las concentraciones de 25%, 12,5% y 6,25%, alcanzaron una eficacia de 73,53%, 77,07% y 50 93%, respectivamente. Los resultados mostraron mayor sensibilidad de las garrapatas a concentraciones más elevadas. Propóleos puede ser una opción de tratamiento, pudiendo ser utilizado como una fuente para actividad acaricida debido a sus numerosas sustancias funcionales.