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1.
Protein Expr Purif ; 206: 106254, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36804950

RESUMO

Acinetobacter baylyi is an interesting model organism to investigate bacterial metabolism due to its vast repertoire of metabolic enzymes and ease of genetic manipulation. However, the study of gene expression in vitro is dependent on the availability of its RNA polymerase (RNAp), an essential enzyme in transcription. In this work, we developed a convenient method of producing the recombinant A. baylyi ADP1 RNA polymerase holoenzyme (RNApholo) in E. coli that yields 22 mg of a >96% purity protein from a 1-liter shake flask culture. We further characterized the A. baylyi ADP1 RNApholo kinetic profile using T7 Phage DNA as template and demonstrated that it is a highly transcriptionally active enzyme with an elongation rate of 24 nt/s and a termination efficiency of 94%. Moreover, the A. baylyi ADP1 RNApholo has a substantial sequence identity (∼95%) with the RNApholo from the human pathogen Acinetobacter baumannii. This protein can serve as a source of material for structural and biological studies towards advancing our understanding of genome expression and regulation in Acinetobacter species.


Assuntos
Acinetobacter baumannii , Acinetobacter , Humanos , Escherichia coli/genética , Escherichia coli/metabolismo , Acinetobacter/genética , Acinetobacter/metabolismo , RNA Polimerases Dirigidas por DNA/genética , RNA Polimerases Dirigidas por DNA/metabolismo , Acinetobacter baumannii/genética , Holoenzimas/metabolismo
2.
J Ethnopharmacol ; 202: 147-153, 2017 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-28288826

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Dolichandra unguis-cati L. is a native climbing plant of Brazil, popularly known as "unha de gato". It has been traditionally used mainly as an antipyretic, anti-inflammatory and anti-tumor agent, yet little toxicological information is found in the literature. AIM OF THE STUDY: To identify the chemical composition of the hydroethanolic extract obtained from the leaves of Dolichandra uniguis-cati and to evaluate the acute and subacute toxicity in male and female rats, in order to assess the safety profile of this plant. MATERIALS AND METHODS: In the acute study, a single dose (2000mg/kg) of the extract was orally administered to male and female rats. In the subacute study, the extract was orally administered to male and female rats at doses 100, 200 and 400mg/kg for 28 days. Behavioral changes, catalase and tbars evaluations, biochemical, hematological and histopathological analysis were determined. The extract' chemical composition was accessed through UHPLC/MS. RESULTS: Chlorogenic acid, caffeic acid, ferulic acid, vanillinic acid, p-coumaric acid, rosmarinic acid, trans-cinnamic acid, luteolin, apigenin, quercitrin and quercetin were identified in the extract. In the acute treatment, the extract was classified as safe (category 5), according to the OECD guide. In relation to the subacute study, females showed a reduction in AST (100, 200 and 400mg/kg), ALT (200mg/kg) and BUN (100 and 200mg/kg) levels, while male rats 400mg/kg presented an increase in AST levels. The Chol dosage significantly decreased in female rats in a dose-dependent manner, whereas for male rats this parameter showed no statistically significant reductions. No behavioral and histopathological changes were recorded. CONCLUSIONS: Our results indicate that the hydroethanolic extract of Dolichandra unguis-cati leaves did not present relevant toxic effects when administered orally to male and female rats. The extract also showed a potential hypocholesterolemic activity.


Assuntos
Bignoniaceae/toxicidade , Extratos Vegetais/toxicidade , Folhas de Planta/toxicidade , Animais , Antioxidantes/farmacologia , Aspartato Aminotransferases/metabolismo , Comportamento Animal/efeitos dos fármacos , Bignoniaceae/química , Catalase/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/enzimologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Relação Dose-Resposta a Droga , Feminino , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/patologia , Masculino , Extratos Vegetais/análise , Folhas de Planta/química , Ratos
3.
Rev. cuba. farm ; 49(3)jul.-set. 2015.
Artigo em Inglês | LILACS, CUMED | ID: lil-779734

RESUMO

Scutia buxifolia has been used in the treatment of a number of diseases, which includes bacterial and fungal infections, hypertension, Alzheimer's Disease and cancer. S. buxifolia contains biologically active compounds such as flavonoids, steroids, tanins, lipids, terpens and alkaloids. A range of biological activities has been found from plant extract and fractions, including antioxidant, acetylcholinesterase inhibitor, antiviral and antibiotic. Some studies about the potential toxicity were performed; however the results are not conclusive, suggesting that a single administration of the extract is safe, whereas prolonged use has deleterious effects for the body. The revised databases were SciELO, PubMed, ScienceDirect and Portal da Capes considering studies between 1964 and 2014 and by searching for terms like Scutia buxifolia, Rhamnaceae family, Scutia buxifolia Constituents, Scutia buxifolia use and OECD(AU)


Scutia buxifolia se utiliza en el tratamiento de una serie de enfermedades que incluye infecciones bacterianas y fúngicas, hipertensión, enfermedad de Alzheimer y cáncer. S. buxifolia contiene compuestos biológicamente activos tales como flavonoides, taninos, esteroides, lípidos, terpenos y alcaloides. A partir del extracto y las fracciones de la planta surgen una gama de actividades biológicas, que incluyen antioxidante, inhibidor de la acetilcolinesterasa, antiviral y antibiótico. Se realizaron algunos estudios sobre el potencial tóxico, sin embargo los resultados no son concluyentes, lo que sugiere que una sola administración del extracto es segura, mientras que el uso prolongado tiene efectos perjudiciales para el organismo. Las bases de datos revisadas fueron SciELO, PubMed, ScienceDirect y Portal de Capes, teniendo en cuenta los estudios entre 1964 y 2014 y mediante la búsqueda de términos como Scutia buxifolia, Rhamnaceae family, Scutia buxifolia constituents, Scutia buxifolia uses and OECD(AU)


Assuntos
Humanos , Rhamnaceae/efeitos dos fármacos , Preparações de Plantas/toxicidade , Preparações de Plantas/uso terapêutico , Medicamentos de Referência
4.
Rev. cuba. farm ; 49(3)jul.-set. 2015.
Artigo em Inglês | LILACS, CUMED | ID: lil-779736

RESUMO

The genus Bauhinia (Fabaceae, Leguminosae) consists of approximately 300 species, which are commonly known as cows paw or cows hoof, because of the shape of their leaves. They are widely distributed in most tropical countries, including Africa, Asia and South America. Their leaves and stem-bark have been used frequently in folk medicine as a remedy for different kinds of disease, particularly diabetes, infections, pain and inflammatory processes. Bauhinia longifolia flavonoids demonstrated the highest antiviral activity of all tested substances, being that quercetin had the highest antiviral activity amongst purified flavonoids. The aim of this article is to summarize concisely recent advances published in the last 5 years on the most recent works about the biological activities and phytochemical composition of plants of the genusBauhinia. For this, was performed a search in some of the databases on the web as PubMed, Google Scholar and Medline, using the keywords Bauhinia, biological properties, diabetes, cancer(AU)


El género Bauhinia (Fabaceae, Leguminosae) consta de aproximadamente 300 especies, que se conocen comúnmente como pata de vaca o pezuña de vaca, debido a la forma de sus hojas. Están ampliamente distribuidos en la mayoría de los países tropicales, incluyendo África, Asia y América del Sur. Sus hojas y el tallo de corteza se utilizan con frecuencia en la medicina popular como un remedio para diferentes tipos de enfermedades, en particular la diabetes, infecciones, dolor y en los procesos inflamatorios. Los flavonoides de Bauhinia longifolia demostraron la mayor actividad antiviral de todas las sustancias analizadas, y es la quercetina la de mayor actividad antiviral entre los flavonoides purificados. El objetivo de este artículo fue resumir los trabajos publicados en los últimos cinco años sobre la actividad biológica y la composición fitoquímica de las plantas del género Bauhinia. Para ello, se realizó una búsqueda en algunas de las bases de datos en la web como PubMed, Google Scholar y Medline, usando las palabras clave Bauhinia, actividad biológica, diabetes, cáncer(AU)


Assuntos
Humanos , Bauhinia , Diabetes Mellitus/tratamento farmacológico , Neoplasias/tratamento farmacológico , Brasil
5.
Rev. cuba. farm ; 49(1)ene.-mar. 2015. ilus, graf
Artigo em Inglês | LILACS, CUMED | ID: lil-771002

RESUMO

Introduction: essential oils and aromatic plant extracts have been recognized for many years as a great source of pharmaceutical agents. It is important to research on the chemical composition of the essential oils of plants widely used by the population because its usability becomes safer. Objective: to identify the chemical characterization of Schinus molle L. essential oils and their biological activities and to compare them with the biological activities of the main compounds found in literature. Methods: fifty grams of leaves were used to extract the oils through distillation in a modified Clevenger apparatus. The chemical analysis of volatile oils was carried out with capillary gas chromatography using flame ionization detector for quantitative analysis of its elements and, subsequently, a mass detector for qualitative analysis. Results: nineteen substances were separated and the major compounds were bicyclogermacrene (20.5 percent percent), betacaryophyllene (19.7 percent) and spathulenol (19.2 percent). Conclusions: given the extensive distribution of the raw material in Rio Grande do Sul state, Brazil, more studies on the chemical properties and biological activities of Schinus molle essential oil are needed(AU)


Introducción: los aceites esenciales y extractos de plantas aromáticas han sido reconocidos desde hace muchos años como una gran fuente de agentes farmacéuticos. Es importante la investigación de la composición química de los.aceites esenciales de las plantas utilizadas ampliamente por la población porque su aplicabilidad se torna más segura. Objetivo: identificar la composición química del aceite esencial de las hojas de Schinus molle L. y correlacionarlas con las actividades biológicas de los principales compuestos localizadas en la literatura. Métodos: cincuenta gramos de hojas se sometieron a extracción a través de destilación usando un equipo Clevenger modificado. Para el análisis químico, los aceites volátiles se sometieron a cromatografía capilar de gases usando un detector de ionización de llama para el análisis cuantitativo de sus elementos constituyentes y, posteriormente, un detector de masas para el análisis cualitativo. Resultados: diecinueve compuestos fueron separados y los principales eran biciclogermacreno (20,5 por ciento), betacariofileno (19,7 por ciento) y espatulenol (19,2 por ciento). Conclusiones: dada la extensa distribución del material crudo en el estado de Río Grande do Sul, Brasil, se debe incrementar los estudios sobre las características químicas y las actividades biológicas del aceite esencial de Schinus molle(AU)


Assuntos
Humanos , Schinus molle/uso terapêutico , Brasil , Cromatografia Gasosa/métodos
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