Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Braz. j. biol ; 81(2): 387-391, 2021. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1153349

RESUMO

Poor storage conditions provide favorable environment to stored grain pests for their growth. The bio-pesticides are the best alternatives to synthetic pesticides. Present study was conducted to compare toxicity of Rubus fruticosus and Valeriana jatamansi against granary weevil, Sitophilus granarius and subsequent changes in enzyme activity responsible for grain damage. In current research 5 g of R. fruticosus fruit and V. jatamansi rhizome powders were tested separately against S. granarius, in 50 g wheat whole grains for seven days in comparison with the control. The enzymatic activity of malate dehydrogenase and α-amylase was observed in the cellular extracts of S. granarius. The insects were crushed and homogenized in phosphate-buffer solution and centrifuged at 10000 rpm for 5 minutes. For the enzymatic measurement supernatant was tested; the spectrophotometer was adjusted at 340 nm. The reagents were mixed and incubated at 25 °C for five minutes. The cuvettes were placed in the experimental and reference sites of spectrophotometer and recorded the change in absorbance for 3-4 minutes. There was 5.60% and 14.92% reduction in the activity of malate dehydrogenase in R. fruticosus and V. jatamansi, treated insects, respectively. The alpha amylase enzyme activity was 6.82% reduced and 63.63% increase in R. fruticosus and V. jatamansi, treated insects, respectively. Present study addresses that both plant powders are effective against granary weevil by altering enzyme activities so both the plant powders can be used as bio-pesticides against the stored grains pests.


As más condições de armazenamento proporcionam um ambiente favorável às pragas armazenadas para o crescimento. Os biopesticidas são as melhores alternativas aos pesticidas sintéticos. O presente estudo foi conduzido para comparar a toxicidade de Rubus fruticosus e Valeriana jatamansi contra gorgulhos, Sitophilus granarius e subsequentes alterações na atividade enzimática responsáveis ​​por danos aos grãos. Na pesquisa atual, 5 g de frutos de R. fruticosus e pós de rizoma de V. jatamansi foram testados separadamente contra S. granarius, em 50 g de grãos integrais de trigo por sete dias, em comparação com o controle. A atividade enzimática da malato desidrogenase e α-amilase foi observada nos extratos celulares de S. granarius. Os insetos foram esmagados e homogeneizados em solução tampão fosfato e centrifugados a 10000 rpm por 5 minutos. Para a medição enzimática, o sobrenadante foi testado; o espectrofotômetro foi ajustado a 340 nm. Os reagentes foram misturados e incubados a 25 °C por cinco minutos. As cubetas foram colocadas nos locais experimentais e de referência do espectrofotômetro e registradas as alterações na absorbância por 3-4 minutos. Houve redução de 5,60% e 14,92% na atividade da malato desidrogenase em R. fruticosus e V. jatamansi, insetos tratados, respectivamente. A atividade da enzima alfa amilase foi reduzida em 6,82% e aumento de 63,63% em R. fruticosus e V. jatamansi, insetos tratados, respectivamente. O presente estudo aborda que ambos os pós de plantas são eficazes contra o gorgulho do celeiro, alterando as atividades enzimáticas, de modo que ambos os pós de plantas possam ser usados ​​como biopesticidas contra pragas de grãos armazenados.


Assuntos
Animais , Valeriana/toxicidade , Gorgulhos , Agentes de Controle Biológico/administração & dosagem , Rubus/toxicidade , Controle Biológico de Vetores/métodos , alfa-Amilases , Armazenamento de Alimentos/normas , Malato Desidrogenase
2.
Ther Umsch ; 68(1): 54-7, 2011 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-21184395

RESUMO

Herbal medicines are used by many patients. Their known or potential adverse events should be taken into account during treatment with herbal medicines. In this article adverse effects of commonly used herbs are presented. St. John's wort is known to be a potent inducer of cytochrome P450 (CYP) 3A4 leading to reduced blood concentrations of a number of CYP3A4 substrates. For many other combinations evidence is sparse but due to a number of case reports of adverse interactions they should only cautiously be combined with certain critical dose drugs until their risk is fully assessed. Pertinent examples are the immunostimulant Echinacea which could decrease the effect of immunosuppressants. Ginseng and ginkgo should not be combined with anticoagulants. Excessive sedation may occur with concomitant use of valerian and barbiturates.


Assuntos
Interações Ervas-Drogas , Fitoterapia/efeitos adversos , Preparações de Plantas/toxicidade , Citocromo P-450 CYP3A/efeitos dos fármacos , Echinacea/toxicidade , Indução Enzimática , Ginkgo biloba/toxicidade , Humanos , Hypericum/toxicidade , Panax/toxicidade , Extratos Vegetais/toxicidade , Valeriana/toxicidade
3.
Colomb. med ; 41(3): 256-266, jul.-sept. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-573004

RESUMO

Introduction: One of the most frequent problems found in medicinal plants is the absence of clinical, toxicological, and pharmacological studies. Valeriana pavonii is one of the species used in Colombia as an anxiolytic. Further study of this specie is rendered to add information in the toxicological area. Objective: The acute and subchronic oral toxicity of V. pavonii ethanolic extract was evaluated in Wistar rats of both sexes. Materials and methods: The rats were distributed into four groups: the control group received the vehicle (0.5 mL/100 g of corporal weight) and the other three groups received increasing levels of the dosage for 90 days to evaluate characteristics like physical exam, laboratory test (blood chemistry and haematology), and anatomopathological findings. Results: This study reveals that there were no signs of toxicity, mortality, or significant alterations attributable to the ethanolic extract of V. pavonii. Conclusions: The Not Observed Adverse Effect Levels (NOAEL) of V. pavonii ethanolic extract were 2000 and 1000 mg/kg of body weight for the acute and subchronic toxicity studies, respectively.


Introducción: Uno de los problemas más frecuentes asociados con el uso de plantas medicinales es la ausencia de evidencias farmacológicas, toxicológicas y clínicas. Valeriana pavonii es una de las especies más utilizadas popularmente en Colombia con fines ansiolíticos. Es necesario avanzar en el estudio de esta especie para aportar información en el campo toxicológico. Objetivos: Evaluar la toxicidad oral aguda y sub-crónica del extracto etanólico de V. pavonii en ratas Wistar de ambos sexos. Materiales y métodos: En cada uno de los estudios se distribuyeron ratas en cuatro grupos; un grupo control que recibió únicamente vehículo (0.5 ml/100 g de peso corporal) y tres grupos correspondientes a niveles crecientes de dosis, así: para el estudio de toxicidad aguda se administraron en dosis única 20, 200 y 2000 mg/kg con un período de observación de 14 días y para el de toxicidad sub-crónica, dosis diarias de 250, 500 y 1000 mg/kg durante 90 días. Se evaluaron los parámetros de examen físico, los exámenes de laboratorio (química sanguínea y hematología) y el estudio anatomopatológico. Resultados: No se presentaron signos de toxicidad, letalidad ni alteraciones significativas atribuibles al consumo del extracto etanólico de V. pavonii, según el examen físico, el examen anatomopatológico y el análisis de las pruebas de química sanguínea y hematología. Conclusiones: Los valores de nivel sin efectos adversos observados (NOAEL) del extracto etanólico de V. pavonii, fueron 2000 y 1000 mg/kg de peso corporal para los estudios de toxicidad aguda y sub-crónica, respectivamente. No se encontraron valores de nivel más bajo de efecto adverso observado (LOAEL).


Assuntos
Animais , Ratos , Ansiolíticos/farmacologia , Ansiolíticos/toxicidade , Plantas Medicinais/toxicidade , Testes de Toxicidade/classificação , Testes de Toxicidade/estatística & dados numéricos , Testes de Toxicidade/métodos , Testes de Toxicidade/veterinária , Valeriana , Valeriana/toxicidade , Etanol/farmacologia , Etanol/toxicidade
4.
Phytother Res ; 23(1): 33-40, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19048610

RESUMO

Associations of plants have been widely used, for centuries, in Ayurveda and in Chinese medicine and have been increasingly acknowledged in Western medicine. The objective of this study is to assess the level of toxicity of an association of three plants: Crataegus oxyacantha, Passiflora incarnata, and Valeriana officinalis (CPV extract). This association was administered to rats, mice, and dogs, both acute and chronically for 180 days. The tests used in the acute experiments were: observational pharmacological screening, LD(50), motor coordination and motor activity. Chronic tests carried out were: weight gain/loss and behavioral parameters in rats and in mice; estrus cycle, effects on fertility, and teratogenic studies in rats and of mutagenic features in mice, in addition to the Ames test. The following parameters were assessed in dogs: weight gain/loss, general physical conditions, water/food consumption and anatomopathological examination of the organs subsequent to the 180 days of treatment. All of the results were negative, showing that CPV administered in high doses and over a long period of time presents no toxicity, suggestive of the fact that this is an association devoid of risk for human beings.


Assuntos
Crataegus/toxicidade , Passiflora/toxicidade , Extratos Vegetais/toxicidade , Valeriana/toxicidade , Animais , Cães , Relação Dose-Resposta a Droga , Estro/efeitos dos fármacos , Feminino , Fertilidade/efeitos dos fármacos , Dose Letal Mediana , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Testes de Mutagenicidade , Ratos , Ratos Wistar , Testes de Toxicidade Aguda , Testes de Toxicidade Crônica , Aumento de Peso/efeitos dos fármacos , Redução de Peso/efeitos dos fármacos
5.
Food Chem Toxicol ; 44(11): 1830-7, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16879905

RESUMO

Valerian is widely known for its use as a sedative and an anti-anxiety drug in the folk medicine. Literature reports suggested valerian to induce genotoxicity in vitro (ECV304 cells) by reactive oxygen species-mediated mechanism; however, there are no reports on its genotoxicity and/or the epigenetic mechanism in vivo. In view of the folkloric significance, it was found worthwhile to (1) determine the genotoxic effects of valerian in somatic and germ cells of mice and (2) investigate the role of epigenetic mechanisms. The protocol included the oral treatment of mice with different doses (500, 1000 and 2000 mg/kg/day) of valerian for 7 days. The following experiments were conducted: (i) cytological studies on micronucleus test, (ii) cytogenetic analysis for meiotic chromosomes, (iii) cytological analysis of spermatozoa abnormalities, (iv) quantification of proteins and nucleic acids in testicular cells and (v) estimation of malondialdehyde (MDA) and nonprotein sulfhydryl (NP-SH) in hepatic and testicular cells. The treatment increased the frequency of micronuclei in the polychromatic erythrocytes (PCE) and decrease the ratio of PCE to normochromatic erythrocytes (NCE) in the femur. It caused aberrations in chromosomes of the testis and induced spermatozoa abnormalities. The concentration of nucleic acids was depleted in the testicular cells. These changes might be attributed to the epigenetic mechanisms as revealed by an increase in the concentrations of MDA and a decrease of NP-SH levels in hepatic and testicular cells observed in the present study. The observed changes may be ascribed to terpenoids (valepotriates) and flavonoids (6-methylapigenin and 2S(-)-hesperidin) present in valerian.


Assuntos
Fígado/efeitos dos fármacos , Mutagênicos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Valeriana/toxicidade , Administração Oral , Animais , Células Cultivadas , Aberrações Cromossômicas/induzido quimicamente , Relação Dose-Resposta a Droga , Eritrócitos/efeitos dos fármacos , Humanos , Fígado/metabolismo , Fígado/patologia , Masculino , Malondialdeído/metabolismo , Meiose/efeitos dos fármacos , Camundongos , Testes para Micronúcleos , Mutagênicos/classificação , Ácidos Nucleicos/efeitos dos fármacos , Ácidos Nucleicos/metabolismo , Espermatozoides/patologia , Compostos de Sulfidrila/metabolismo , Testículo/metabolismo , Testículo/patologia , Valeriana/classificação
6.
Prescrire Int ; 14(77): 104-7, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15984105

RESUMO

(1) Insomnia should be treated first with non drug measures; this has traditionally involved the use of herbal remedies. (2) About 20 plants are approved in France in the production of medications 'traditionally used' for minor sleep disturbances. Virtually nothing is known of their efficacy or potential dangers. (3) Most of these plants are suspected of toxicity and should therefore be avoided, especially in view of their unproven efficacy. (4) Littleleaf linden, vervain, melissa and orange flower have no demonstrated efficacy but are safe and can therefore be used. Similarly, there are no scientific grounds for rejecting preparations based on hawthorn or passiflora. (5) Available data suggest that valerian extracts have a modest impact on subjective sleep quality; they are nevertheless more effective than a placebo. Valerian products that do not contain valepotriates have no apparent adverse effects. It is best to avoid high-titre alcoholic extracts and powdered valerian root, and to select aqueous extracts and low-titre hydro-alcoholic preparations.


Assuntos
Medicina Herbária , Fitoterapia , Preparações de Plantas/uso terapêutico , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Valeriana , Anemone/efeitos adversos , Ballota/efeitos adversos , Benzodiazepinas/uso terapêutico , Bebidas , Doença Hepática Induzida por Substâncias e Drogas , Ensaios Clínicos como Assunto , Crataegus , Humanos , Humulus , Iridoides/uso terapêutico , Melissa , Passiflora , Preparações de Plantas/toxicidade , Tilia , Valeriana/toxicidade , Verbena
7.
Clin Exp Pharmacol Physiol ; 30(10): 799-804, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14516421

RESUMO

1. The aim of the present study was to investigate the effects of peppermint oil and valerian on rat liver and cultured human hepatoma cells. 2. Rats received a single oral dose of peppermint oil (8.3-830 microL/kg) or valerian (0.31-18.6 g/kg), or daily oral doses of 83 microL/kg peppermint oil or 3.1 g/kg valerian for 28 days. After 24 h, rats were anaesthetized and measurements made of bile flow, liver function and in vivo sinusoidal area. Livers were then removed for histology. 3. Bile flow was unaffected by any treatment, except acute high-dose peppermint oil (830 microL/kg; 70% increase in flow). No change in liver enzyme activity was found, except for a 45% increase in alkaline phosphatase after chronic peppermint oil. No change in sinusoidal area in vivo or in histology was found following any treatment, although pretreatment with carbon tetrachloride reduced sinusoidal bed area and produced histological damage. Incubation of human hepatoma cells with 0.5 microL/mL (but not 0.05 microL/mL) peppermint oil or 20 mg/mL (but not 2 mg/mL) valerian resulted in increased cell death. 4. In conclusion, the present study demonstrated in vitro toxicity of high doses of valerian and peppermint oil in cultured human hepatoma cells and, at doses 2-3 orders of magnitude greater than those recommended for human use, an increase in rat bile flow after acute peppermint oil and an increase in alkaline phosphatase after chronic peppermint oil.


Assuntos
Fígado/efeitos dos fármacos , Óleos de Plantas/toxicidade , Valeriana/toxicidade , Animais , Bile/efeitos dos fármacos , Bile/metabolismo , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Humanos , Fígado/metabolismo , Fígado/patologia , Masculino , Mentha piperita , Óleos de Plantas/administração & dosagem , Ratos , Ratos Long-Evans
8.
Toxicol Appl Pharmacol ; 188(1): 36-41, 2003 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-12668120

RESUMO

To study the genotoxicity of valepotriates in vitro, the degree of DNA damage in human endothelial cell line ECV304 treated with 5-60 microg/mL of dichloromethane extracts of valerian (DEV) was analyzed by the Comet assay. No DNA damage was observed in ECV304 cells after culture for 48 h in the presence of 5,10, and 20 microg/mL of DEV. But a moderate degree of DNA damage was observed in the cells treated with 40 or 60 microg/mL of DEV. Quantitative analyses of DNA damage in the presence of antioxidants vitamin E (VE) and vitamin C (VC) were also carried out. The study revealed that both VE and VC exhibited a biphasic effect, reducing DEV-induced DNA damages at low concentrations but increasing them at high concentrations. We concluded that (1). the observed DNA damage in ECV304 cells induced by high concentrations of DEV was mainly through epigenetic mechanisms, i.e., reactive oxygen species mediated oxidative DNA damage (2). at the low doses, DEV did not appear to have any significant genotoxicity in ECV304 cells, and (3). VE and VC, at proper concentrations, can reduce or eliminate the adverse effects derived from high doses of DEV. This study should serve as scientific guidance for clinical therapy of valerian preparation.


Assuntos
Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Dano ao DNA/efeitos dos fármacos , Valeriana/toxicidade , Vitamina E/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Humanos , Cloreto de Metileno/química , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/toxicidade , Raízes de Plantas/toxicidade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...