RESUMO
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.
Assuntos
Antimitóticos , Stevia , Animais , Antioxidantes/farmacologia , Mamíferos , Camundongos , Componentes Aéreos da Planta , Extratos Vegetais/farmacologia , ToxicogenéticaRESUMO
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.
Assuntos
Actinobacteria/isolamento & purificação , Actinobacteria/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Antiprotozoários/farmacologia , Asteraceae/microbiologia , Produtos Biológicos/farmacologia , Metabolismo Secundário , Actinobacteria/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antiprotozoários/química , Antiprotozoários/isolamento & purificação , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Brasil , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Testes de Sensibilidade Parasitária , Plantas Medicinais/microbiologia , Relação Estrutura-Atividade , Trypanosoma cruzi/efeitos dos fármacosRESUMO
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.
Assuntos
Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antibióticos Antineoplásicos/isolamento & purificação , Antibióticos Antineoplásicos/farmacologia , Benzofenonas/isolamento & purificação , Benzofenonas/farmacologia , Própole/química , Actinomyces/efeitos dos fármacos , Animais , Antibacterianos/análise , Antibacterianos/toxicidade , Antibióticos Antineoplásicos/análise , Antibióticos Antineoplásicos/toxicidade , Aderência Bacteriana/efeitos dos fármacos , Abelhas/metabolismo , Benzofenonas/análise , Benzofenonas/toxicidade , Brasil , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Humanos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Estrutura Molecular , Mutação , Prenilação , Staphylococcus/efeitos dos fármacos , Staphylococcus/genéticaRESUMO
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.
Assuntos
Antraquinonas/isolamento & purificação , Antiprotozoários/isolamento & purificação , Asteraceae/química , Leishmania major/efeitos dos fármacos , Raízes de Plantas/química , Animais , Antraquinonas/química , Antraquinonas/farmacologia , Antiprotozoários/química , Antiprotozoários/farmacologia , Cromonas , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologiaRESUMO
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.
Assuntos
Asteraceae/química , Flavonoides/química , Glicosídeos/química , Componentes Aéreos da Planta/química , Flavonas , Glicosídeos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura MolecularRESUMO
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.
Assuntos
Anti-Infecciosos/farmacologia , Asteraceae , Fitoterapia , Extratos Vegetais/farmacologia , Anti-Infecciosos/administração & dosagem , Anti-Infecciosos/uso terapêutico , Candida/efeitos dos fármacos , Flores , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Folhas de Planta , Raízes de PlantasRESUMO
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.
Assuntos
Mikania , Fitoterapia , Extratos Vegetais/farmacologia , Terpenos/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Doença de Chagas/prevenção & controle , Humanos , Testes de Sensibilidade Parasitária , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Terpenos/administração & dosagem , Terpenos/uso terapêutico , Tripanossomicidas/administração & dosagem , Tripanossomicidas/uso terapêuticoRESUMO
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.