ABSTRACT
Plant species have been used for therapeutic purposes since ancient times and are still in use today since these products represent a source of raw material for the production of phytotherapeutic formulations. Screening and investigation of plants with pharmacological potential require the evaluation of characteristics related to their action, efficacy and safety in different steps. Among these steps, pre- clinical trials are used to evaluate the properties of the test product in in vitro experiments, such as cytotoxicity assays. Within this context, this study consists of a bibliometric analysis of some in vitro cytotoxicity and toxicity assays in erythrocytes used during bioprospecting of medicinal plants. The results demonstrated the wide application of erythrocytes to evaluate the biological effects of medicinal plant extracts. The methods were found to be valid and effective for the preliminary investigation of the in vitro cytotoxicity and toxicity of plant products.
El uso de especies vegetales para fines terapeÌuticos es una praÌctica histoÌrica y todaviÌa bastante actual, ya que estos productos pueden representar una fuente de materia prima para la produccioÌn de formulaciones fitoteraÌpicas. En investigacioÌn de plantas con potencial farmacoloÌgico requiere la evaluacioÌn de su accioÌn, eficacia y seguridad, a traveÌs de diferentes etapas. Entre estas, en los ensayos precliÌnicos se evaluÌan las propiedades del producto-prueba en experimentos in vitro, tales como ensayos de citotoxicidad, entre otros. En este aspecto, el presente estudio consiste en un anaÌlisis bibliomeÌtrico acerca de algunas pruebas de citotoxicidad y toxicidad in vitro en eritrocitos realizados en los ensayos de bioprospeccioÌn de plantas medicinales. Los resultados evidencian la amplia utilizacioÌn de eritrocitos para la evaluacioÌn de los efectos bioloÌgicos de extractos de plantas medicinales, apuntaÌndolos como meÌtodos vaÌlidos y eficaces para la investigacioÌn preliminar de la citotoxicidad y toxicidad in vitro de productos vegetales.
Subject(s)
Biological Assay/methods , Plant Extracts/toxicity , Erythrocytes/drug effects , Antioxidants/toxicity , Osmotic Fragility , Oxidative Stress , Erythrocytes/cytology , Bioprospecting , Hemolysis/drug effectsABSTRACT
Vatairea macrocarpa (Benth.) Ducke, Fabaceae, is popularly known as 'angelim'. Its heartwood macerate is used to treat inflammation, gastric ulcer, diabetes and infections. The oral acute and subchronic toxicity of the methanol extract of V. macrocarpa heartwood (MEVm) was evaluated. In the Hippocratic screening, a single administration of MEVm was given orally to mice at doses ranging from 100 to 5000 mg/kg. In the subchronic study, MEVm was given orally as a daily administration for thirty days to Wistar rats at doses of 20, 100 and 500 mg/kg. In Hippocrtaic screening, doses of MEVm up to 5000 mg/kg did not cause any relevant behavioral changes or deaths thus making it impossible to establish the LD50. In subchronic assay, body weight gains and food intake were significantly reduced at the last week of treatment with 20 and 500 mg/kg dose. Serum triacylglycerides, total proteins and γ-glutamyltransferase activity were significantly reduced, while alkaline phosphatase activity was elevated. In hematological parameters, MEVm increased the percentage of segmented neutrophils cells at the highest dose. All alterations observed were minor in nature and were not accompanied by any relevant clinical signs or any histopathological changes. In conclusion, the results demonstrate relative safety profile of MEVm in the experimental animals.
ABSTRACT
Optimization of chicken feather (CF) based culture medium for the production of Bacillus thuringiensis subsp. israelensis (Bti) biomass in combination with the agro industrial by-product (coconut cake, CC) and manganese chloride (MnCl2) has been evaluated. The biomass yield of Bti spore/crystal toxin was highest (12.06 g/L) from the test medium (CF+CC+MnCl2) compared to the reference medium (Luria Bertani, LB). Toxicity assay with Bti produced from the test medium against mosquito vectors (Culex quinquefasciatus, Anopheles stephensi and Aedes aegypti) was also satisfactory and results were comparable with bacteria produced from LB. The results suggest that Bti can be produced to the maximum extent possible as a potential mosquitocidal activity as suggested by the test medium (CF+CC+MnCl2).