RESUMEN
Stevia urticifolia Thunb. is an underexploited herb possessing bioactive flavonoids, saponins, and terpenoids. The aim of this study was to examine the antiproliferative and toxicogenetic properties of the ethyl acetate extract from Stevia urticifolia aerial parts (EtAcSur) upon Artemia salina, erythrocytes, Allium cepa and sarcoma 180 cells and fibroblasts, as well as in vivo studies on mice to determine systemic, macroscopic, and behavioral alterations and bone marrow chromosomal damage. The assessment using A. salina larvae and mouse blood cells revealed LC50 and EC50 values of 68.9 and 113.6 µg/ml, respectively. Root growth and mitosis were inhibited by EtAcSur, and chromosomal aberrations were detected only at 100 µg/ml. EtAcSur exhibited potent concentration-dependent viability reduction of S180 and L-929 cells and antioxidant capacity employing ABTS⢠and DPPHâ¢. No previous in vivo studies were performed before with the EtAcSur. Signals of acute toxicity were not observed at 300 mg/kg. Physiological and toxicological investigations at 25 and 50 mg/mg/day i.p. for 8 days did not markedly change body or organ relative weights, nor patterns of spontaneous locomotor and exploratory activities. In contrast, clastogenic effects on bone marrow were found at 50 mg/mg/day. EtAcSur was found to (1) produce toxicity in microcrustaceans, (2) capacity as free radical scavenger, (3) antimitotic, cytotoxic and clastogenic activties upon vegetal and mammalian cells, and (4) lethality on both tumor and normal murine cells indistinctly. In vivo damage systemic effects were not remarkable and clinical signals of toxicity were not observed, suggesting the significant pharmacological potential of S. urticifolia for the development of antineoplastic agents.Abbreviations: ABTS: 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid); DMSO: dimethylsulfoxide; DPPH: 1,1-diphenyl-2-picrylhydrazyl; EC50: effective concentration 50%; EtAcSur: ethyl acetate extract from Stevia urticifolia aerial parts; Hb, hemoglobin; IC50: inhibitory concentration 50%; LC50,: lethal concentration 50%; MI: mitotic index; RBC, red blood cells; Trolox: 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid.
Asunto(s)
Antimitóticos , Stevia , Animales , Antioxidantes/farmacología , Mamíferos , Ratones , Componentes Aéreos de las Plantas , Extractos Vegetales/farmacología , ToxicogenéticaRESUMEN
Endophytic actinobacteria from the Brazilian medicinal plant Lychnophora ericoides were isolated for the first time, and the biological potential of their secondary metabolites was evaluated. A phylogenic analysis of isolated actinobacteria was accomplished with 16S rRNA gene sequencing, and the predominance of the genus Streptomyces was observed. All strains were cultured on solid rice medium, and ethanol extracts were evaluated with antimicrobial and cytotoxic assays against cancer cell lines. As a result, 92% of the extracts showed a high or moderate activity against at least one pathogenic microbial strain or cancer cell line. Based on the biological and chemical analyses of crude extracts, three endophytic strains were selected for further investigation of their chemical profiles. Sixteen compounds were isolated, and 3-hydroxy-4-methoxybenzamide (9) and 2,3-dihydro-2,2-dimethyl-4(1H)-quinazolinone (15) are reported as natural products for the first time in this study. The biological activity of the pure compounds was also assessed. Compound 15 displayed potent cytotoxic activity against all four tested cancer cell lines. Nocardamine (2) was only moderately active against two cancer cell lines but showed strong activity against Trypanosoma cruzi. Our results show that endophytic actinobacteria from L. ericoides are a promising source of bioactive compounds.
Asunto(s)
Actinobacteria/aislamiento & purificación , Actinobacteria/metabolismo , Antineoplásicos Fitogénicos/farmacología , Antiprotozoarios/farmacología , Asteraceae/microbiología , Productos Biológicos/farmacología , Metabolismo Secundario , Actinobacteria/química , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Antiprotozoarios/química , Antiprotozoarios/aislamiento & purificación , Productos Biológicos/química , Productos Biológicos/aislamiento & purificación , Brasil , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Pruebas de Sensibilidad Parasitaria , Plantas Medicinales/microbiología , Relación Estructura-Actividad , Trypanosoma cruzi/efectos de los fármacosRESUMEN
A prenylated benzophenone, hyperibone A, was isolated from the hexane fraction of Brazilian propolis type 6. Its structure was determined by spectral analysis including 2D NMR. This compound exhibited cytotoxic activity against HeLa tumor cells (IC(50)=0.1756microM), strong antimicrobial activity (MIC range-0.73-6.6microg/mL; MBC range-2.92-106microg/mL) against Streptococcus mutans, Streptococcus sobrinus, Streptococcus oralis, Staphylococcus aureus, and Actinomyces naeslundii, and the results of its cytotoxic and antimicrobial activities were considered good.
Asunto(s)
Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Antibióticos Antineoplásicos/aislamiento & purificación , Antibióticos Antineoplásicos/farmacología , Benzofenonas/aislamiento & purificación , Benzofenonas/farmacología , Própolis/química , Actinomyces/efectos de los fármacos , Animales , Antibacterianos/análisis , Antibacterianos/toxicidad , Antibióticos Antineoplásicos/análisis , Antibióticos Antineoplásicos/toxicidad , Adhesión Bacteriana/efectos de los fármacos , Abejas/metabolismo , Benzofenonas/análisis , Benzofenonas/toxicidad , Brasil , Supervivencia Celular/efectos de los fármacos , Células HeLa , Humanos , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos , Estructura Molecular , Mutación , Prenilación , Staphylococcus/efectos de los fármacos , Staphylococcus/genéticaRESUMEN
The dichloromethane extract of Calea uniflora afforded a mixture of two novel chromanones, uniflorol-A (1) and uniflorol-B (2), and one known chromanone, 2,2-dimethyl-6-(1-hydroxyethyl)-chroman-4-one (3). The structures of these compounds were determined by spectroscopic methods. Biological activity of the compounds against Leishmania major promastigotes was evaluated. Mixture of the novel chromanones 1 and 2 showed significant growth inhibition of the parasite in the micrograms per milliliter range.
Asunto(s)
Antraquinonas/aislamiento & purificación , Antiprotozoarios/aislamiento & purificación , Asteraceae/química , Leishmania major/efectos de los fármacos , Raíces de Plantas/química , Animales , Antraquinonas/química , Antraquinonas/farmacología , Antiprotozoarios/química , Antiprotozoarios/farmacología , Cromonas , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacologíaRESUMEN
A new 5-deoxyflavone glycoside, identified as 7-O-(alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl)-3',4',7-trihydroxyflavone (1), was isolated from the aerial parts of Calea clausseniana. Its structure was determined by spectral analysis.
Asunto(s)
Asteraceae/química , Flavonoides/química , Glicósidos/química , Componentes Aéreos de las Plantas/química , Flavonas , Glicósidos/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Estructura MolecularRESUMEN
The antimicrobial activity of dichloromethane extracts (leaves, flowers and underground parts) and some compounds isolated from Calea platylepis were evaluated by the well diffusion method.
Asunto(s)
Antiinfecciosos/farmacología , Asteraceae , Fitoterapia , Extractos Vegetales/farmacología , Antiinfecciosos/administración & dosificación , Antiinfecciosos/uso terapéutico , Candida/efectos de los fármacos , Flores , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/administración & dosificación , Extractos Vegetales/uso terapéutico , Hojas de la Planta , Raíces de PlantasRESUMEN
The in vitro trypanocidal properties of isolated terpenoids from Mikania stipulacea and Mikania hoehnei were investigated in Trypanosoma cruzi Y strain. Both compounds, the diterpene ent-9alpha-hydroxy-15beta-E-cinnamoyloxy-16-kauren-19-oic acid (1) and the sesquiterpene lactone 8beta-hydroxyzaluzanin D (2) were active.
Asunto(s)
Mikania , Fitoterapia , Extractos Vegetales/farmacología , Terpenos/farmacología , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Animales , Enfermedad de Chagas/prevención & control , Humanos , Pruebas de Sensibilidad Parasitaria , Extractos Vegetales/administración & dosificación , Extractos Vegetales/uso terapéutico , Terpenos/administración & dosificación , Terpenos/uso terapéutico , Tripanocidas/administración & dosificación , Tripanocidas/uso terapéuticoRESUMEN
The dichloromethane extract of underground parts of Calea uniflora (Heliantheae, Asteraceae) exhibited trypanocidal and antifungal activities. Four p-hydroxyacetophenone derivatives were isolated as the main compounds: 2-senecioyl-4-(hydroxyethyl)-phenol (1), 2-senecioyl-4-(angeloyloxy-ethyl)-phenol (2), and two new derivatives, 2-senecioyl-4-(methoxyethyl)-phenol (3) and 2-senecioyl-4-(pentadecanoyloxyethyl)-phenol (4). 1 and 4 were active towards Trypanosoma cruzi trypomastigotes, reducing their number by 70 and 71% at 500 microg x mL(-1), whereas 2 and 3 were inactive. All the compounds tested showed antifungal activity with minimal inhibitory concentration values between 500 and 1000 microg x mL(-1) against pathogenic Candida spp. and dermatophytes. The isolation, structure elucidation, NMR spectral assignments and bioactivity results of these compounds are reported.