Assessment of DNA damage by extracts and fractions of Strychnos pseudoquina, a Brazilian medicinal plant with antiulcerogenic activity

Strychnos pseudoquina St. Hil. is a native plant of the Brazilian Savannah, used in popular medicine to treat a number of conditions. Since it contains large quantities of alkaloids with proven antiulcer activity, we tested the genotoxic potential of crude extracts and fractions containing alkaloids and flavonoids from the leaves of this plant, on Salmonella typhimurium and performed the micronucleus test on peripheral blood cells of mice treated in vivo. The results showed that the methanol extract of the leaves of S. pseudoquina is mutagenic to the TA98 (-S9) and TA100 (+S9, -S9) strains of Salmonella. The dichloromethane extract was not mutagenic to any of the tested strains. Fractions enriched with alkaloids or flavonoids were not mutagenic. In vivo tests were done on the crude methanol extract in albino Swiss mice, which were treated, by gavage, with three different doses of the extract. The highest dose tested (1800 mg/kg b.w.) induced micronuclei after acute treatment, confirming the mutagenic potential of the methanol extract of the leaves of S. pseudoquina. In high doses, constituents of S. pseudoquina compounds act on DNA, causing breaks and giving rise to micronuclei in the blood cells of treated animals. © 2006 Elsevier Ltd. All rights reserved.

Phylogenetic systematics of dart-poison frogs and their relatives (Amphibia: Athesphatanura: Dendrobatidae)

The known diversity of dart-poison frog species has grown from 70 in the 1960s to 247 at present, with no sign that the discovery of new species will wane in the foreseeable future. Although this growth in knowledge of the diversity of this group has been accompanied by detailed investigations of many aspects of the biology of dendrobatids, their phylogenetic relationships remain poorly understood. This study was designed to test hypotheses of dendrobatid diversification by combining new and prior genotypic and phenotypic evidence in a total evidence analysis. DNA sequences were sampled for five mitochondrial and six nuclear loci (approximately 6,100 base pairs [bp]; x=3,740 bp per terminal; total dataset composed of approximately 1.55 million bp), and 174 phenotypic characters were scored from adult and larval morphology, alkaloid profiles, and behavior. These data were combined with relevant published DNA sequences. Ingroup sampling targeted several previously unsampled species, including Aromobates nocturnus, which was hypothesized previously to be the sister of all other dendrobatids. Undescribed and problematic species were sampled from multiple localities when possible. The final dataset consisted of 414 terminals: 367 ingroup terminals of 156 species and 47 outgroup terminals of 46 species. Direct optimization parsimony analysis of the equally weighted evidence resulted in 25,872 optimal trees. Forty nodes collapse in the strict consensus, with all conflict restricted to conspecific terminals. Dendrobatids were recovered as monophyletic, and their sister group consisted of Crossodactylus, Hylodes, and Megaelosia, recognized herein as Hylodidae. Among outgroup taxa, Centrolenidae was found to be the sister group of all athesphatanurans except Hylidae, Leptodactyidae was polyphyletic, Thoropa was nested within Cycloramphidae, and Ceratophryinae was paraphyletic with respect to Telmatobiinae. Among dendrobatids, the monophyly and content of Mannophryne and Phyllobates were corroborated. Aromobates nocturnus and Colostethus saltuensis were found to be nested within Nephelobates, and Minyobates was paraphyletic and nested within Dendrobates. Colostethus was shown to be rampantly nonmonophyletic, with most species falling into two unrelated cis- and trans-Andean clades. A morphologically and behaviorally diverse clade of median lingual process-possessing species was discovered. In light of these findings and the growth in knowledge of the diversity of this large clade over the past 40 years, we propose a new, monophyletic taxonomy for dendrobatids, recognizing the inclusive clade as a superfamily (Dendrobatoidea) composed of two families (one of which is new), six subfamilies (three new), and 16 genera (four new). Although poisonous frogs did not form a monophyletic group, the three poisonous lineages are all confined to the revised family Dendrobatidae, in keeping with the traditional application of this name. We also propose changes to achieve a monophyletic higher-level taxonomy for the athesphatanuran outgroup taxa. Analysis of character evolution revealed multiple origins of phytotelm-breeding, parental provisioning of nutritive oocytes for larval consumption (larval oophagy), and endotrophy. Available evidence indicates that transport of tadpoles on the dorsum of parent nurse frogs-a dendrobatid synapomorphy-is carried out primitively by male nurse frogs, with three independent origins of female transport and five independent origins of biparental transport. Reproductive amplexus is optimally explained as having been lost in the most recent common ancestor of Dendrobatoidea, with cephalic amplexus arising independently three times. © American Museum of Natural History 2006.

Mutagenic activity of glycoallkaloids from Solanum palinacanthum dunal (Solanaceae) found in the Brazilian cerrado

Solanaceous plants are widely distributed around the world and they are traditionally used as drugs for the treatment of cancer and herpes, and include familiar foods such as potato, tomato and eggplant and some berries popular in Brazil. As part of a program of research on pharmacologically active new molecules, the aim in this study was to assess the mutagenic effects of Solanum palinacanthum, known popularly as joá. The crude 95% ethanol extract and purified solamargine obtained from the fruits of S. palinacanthum Dunal were investigated by the Ames test, using the Salmonella typhimurium strains TA98, TA97a, TA100 and TA102 as test organisms, with and without metabolic activation. The concentrations tested ranged from 0.07 to 15.0 mg/plate for the crude ethanolic extract and from 1.25 to 5.0 mg/plate for the solamargine. The results showed a mutagenic effect of both the extract and the solamargine in the TA98 strain (without metabolic activation). The present study showed the potential mutagenicity and suggests confirming this effect in other models, before recommending their indiscriminate consumption by the population.

Pharmacognostical evaluation of fruits of Solanum lycocarpum A. St.-Hill. (Solanaceae)

This study describes the chemical and physical-chemical profile of plant drug and ethanolic extract obtained from fruits of Solanum lycocarpum A. St.-Hill. (Solanaceae). The physical and chemical analysis involved the granulometry determination, non-compacted apparent density, loss on drying in oven and in infrared scale, pH, ash values and extractive values. The results determined the physical-chemical characteristics of the drug plant. It was also carried out the microbiological control of the plant drug. The preliminary phytochemical screening featured the presence of tannins, flavonoids and saponins in the plant drug and alkaloids and steroids in the ethanolic exctract. The solamargine and solasonine glycoalkaloids were identified through TLC and GC/ MS. The levels of total phenols and tannins were quantified in the extract (8.90% and 6,85% respectively). Such studies contribute to the chemical identification and quality control of S. lycocarpum fruits. © 2010 Phcog.net.

Estudo fitoquímico preliminar e bioensaio toxicológico frente a larvas de Artemia salina Leach. de extrato obtido de frutos de Solanum lycocarpum A. St.-Hill (Solanaceae)

The phytochemical profile of ethanolic extract of Solanum lycocarpum fruits was analyzed and preliminary toxicity tests were performed against brine shrimp larvae. The extract was subjected to preliminary phytochemical analysis to identify the main classes of secondary metabolites and tested against the larvae of A. salina to obtain the median lethal concentrations (LC50%). The phytochemical tests showed the presence of phenols, tannins, saponins, alkaloids and free steroids. The extract was fractionated with various solvents for toxicity testing against the larvae and the hydroalcoholic fraction showed considerable cytotoxicity (CL50% = 285.546 g/mL).

A simple, rapid method for the extraction of whole fire ant venom (Insecta: Formicidae: Solenopsis)

The invasive fire ant Solenopsis invicta is medically important because its venom is highly potent. However, almost nothing is known about fire ant venom proteins because obtaining even milligram-amounts of these proteins has been prohibitively challenging. We present a simple and fast method of obtaining whole venom compounds from large quantities of fire ants. For this, we separate the ants are from the nest soil, immerse them in dual-phase mixture of apolar organic solvent and water, and evaporate each solvent phase in separate. The remaining extract from the aqueous phase is largely made up of ant venom proteins. We confirmed this by using 2D gel electrophoresis while also demonstrating that our new approach yields the same proteins obtained by other authors using less efficient traditional methods. © 2013 Elsevier Ltd.

Dragon's blood Croton palanostigma induces genotoxic effects in mice

Ethnopharmacological relevance Dragon's blood is a dark-red sap produced by species from the genus Croton (Euphorbiaceae), which has been used as a famous traditional medicine since ancient times in many countries, with scarce data about its safe use in humans. In this research, we studied genotoxicity and clastogenicity of Croton palanostigma sap using the comet assay and micronucleus test in cells of mice submitted to acute treatment. Material and methods HPLC analysis was performed to identify the main components of the sap. The sap was administered by oral gavage at doses of 300 mg/kg, 1000 mg/kg and 2000 mg/kg. For the analysis, the comet assay was performed on the leukocytes and liver cells collected 24 h after treatment, and the micronucleus test (MN) on bone marrow cells. Cytotoxicity was assessed by scoring 200 consecutive polychromatic (PCE) and normochromatic (NCE) erythrocytes (PCE/NCE ratio). Results and conclusion The alkaloid taspine was the main compound indentified in the crude sap of Croton palanostigma. The results of the genotoxicity assessment show that all sap doses tested produced genotoxic effects in leukocytes and liver cells and also produced clastogenic/aneugenic effects in bone marrow cells of mice at the two higher doses tested. The PCE/NCE ratio indicated no cytotoxicity. The data obtained suggest caution in the use of Croton palanostigma sap by humans considering its risk of carcinogenesis. © 2013 Elsevier B.V. All rights reserved.

Ent-labdane and beyerane diterpenes from Erythroxylum betulaceum Mart

•Diterpenes were isolated from wood of Erythroxylum betulaceum Mart.•Two ent-labdanes and one ent-beyrane diterpenes were isolated.•Diterpenes together tropanic alkaloid and may be useful as a chemotaxonomic markers of Erythroxylum. © 2013 Elsevier Ltd.

Avaliação dos efeitos citotóxicos, genotóxicos, mutagênicos, antigenotóxicos, antimutagênicos e anticarcinogênicos do Lupinus albus em camundongos Mus musculus

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Obtenção de extrato aquoso solúvel de tremoço amargo (Lupinus campestris)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Otimização para a obtençao de extrato aquoso de tremoço branco (Lupinus albus L.) adicionado de suco de pitanga

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito antitumoral, genotóxico e mutagênico de nitensidina A em camundongos nude BALB/c com implante tumoral xenográfico de células imortalizadas com HPV-16 (SiHa)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Atividade citotóxica, pró-apoptótica, genotóxica e mutagênica de nitensidina B em células tumorais cervicais humanas

Pós-graduação em Biociências e Biotecnologia Aplicadas à Farmácia - FCFAR

Análise da expressão dos genes envolvidos na via de síntese de cafeína em plantas de café (Coffea arabica) apresentando diferentes teores de cafeína

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo químico dos alcalóides piridínicos encontrados em Senna multijuga

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)