ABSTRACT
O uso de extratos vegetais apresenta grande eiciência no manejo de pragas, destinados a produções agrícolas de pequeno e médio porte, por controlar uma gama muito grande de artrópodes. O objetivo desta pesquisa consiste em avaliar os efeitos tóxicos dos extratos de Anadenanthera macrocarpa (Fabaceae: Mimosoideae) e Bougainvillea buttiana (Nyctaginaceae) em Helicoverpa armigera (Hübner), Spodoptera cosmioides (Walker) e Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae). Lagartas de H. armigera e S. cosmioides foram mantidas em discos foliares de soja, enquanto S. frugiperda foi mantida em discos foliares de milho, tratados com os extratos aquoso diluídos nas concentrações de: 0, 500, 1.000, 2.500, 4.000, 5.000, 10.000 e 15.000 mg.L-1. Foram mensurados os efeitos letais e subletais dos extratos sobre os insetos. De acordo com os resultados obtidos, a concentração de 500 mg.L-1 do extrato de A. macrocarpa causou o maior percentual de mortalidade (93,33%) em H. armigera. O extrato de B. buttiana causou 86,67% e 60% de mortalidade em H. armigera (1.000 mg.L-1) e S. cosmioides (4.000 mg.L-1), respectivamente. A redução da emergência dos adultos foi o principal efeito subletal constatado em S. cosmioides e S. frugiperda. Considerando os resultados obtidos, destaca-se que os extratos vegetais utilizados apresentam-se como uma alternativa em potencial para o manejo de lepidópteros-praga.
For small and medium agricultural production, vegetal extracts are highly eficient at managing pests because they control a wide range of arthropods. The objective of this research was to evaluate the toxic effects of Anadenanthera macrocarpa (Fabaceae: Mimosoideae) and Bougainvillea buttiana (Nyctaginaceae) extracts on Helicoverpa armigera (Hübner), Spodoptera cosmioides (Walker) and Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae). Helicoverpa armigera and S. cosmioides caterpillars were maintained on soybean leaf discs, and S. frugiperda was maintained on corn leaf discs, treated with diluted aqueous extracts at concentrations of 0, 500, 1,000, 2,500, 4,000, 5,000, 10,000 and 15,000 mg.L-1. The lethal and sublethal effects of the extracts on the insects were measured. According to the results, the concentration of 500 mg.L-1 of the A. macrocarpa extract caused the highest percentage of mortality (93.33%) of H. armigera. The extract of B. buttiana caused 86.67% and 60% mortality of H. armigera (1,000 mg.L-1) and S. cosmioides (4,000 mg.L-1), respectively. The reduction of the emergence of adults was the main sublethal effect found for S. cosmioides and S. frugiperda. Considering the results, the vegetal extracts used in this research are a potential alternative for the management of lepidopteran pests.
Subject(s)
Nyctaginaceae/toxicity , Fabaceae/toxicity , Plant Extracts , Pest Control , LepidopteraABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: Boldoa purpurascens Cav. (Nyctaginaceae) is a plant species used in traditional medicine in Cuba as a diuretic. AIM OF THE STUDY: The aim of the present investigation was to evaluate the safety profile of a hydroalcoholic extract from leaves of Boldoa purpurascens. MATERIALS AND METHODS: First, an experimental study to assess the oral acute toxicity at a dose of 2000mg/kg body weight of the extract was carried out. Potential genotoxicity of the extract was evaluated using the Ames test and the micronucleus induction assay in mouse bone marrow. In the Ames test a concentration range of 50, 100, 150, 300 and 500µg/plate was tested. In the micronucleus induction assay, doses of 500, 1000 and 2000mg/kg of body weight were tested. For completeness, since the extract contains saponins, the evaluation of the hemolytic activity, ocular and skin irritation were included. RESULTS: No signs or symptoms of toxicity were observed in the oral acute toxicity test (body weight at baseline, seven days and end of the experiment of 236.41±20.07, 256.81±30.44 and 240.02±26.16 respectively for the treated group). The hydroalcoholic extract from the leaves was not mutagenic in the Ames test, and no genotoxicity was observed in the micronucleus assay. A hemolysis test at concentration of 1mg/mL confirmed hemolytic activity, which is not a safety concern since saponins are not absorbed after oral administration. In order to evaluate the percentage of protein denaturation, the ocular irritability index was calculated. The extract was found to be irritating. Finally, skin irritability was evaluated and the irritation index was equal to zero. CONCLUSIONS: Based on the toxicological evaluation of a traditionally used hydroalcoholic extract from the leaves of Boldoa purpurascens we can confirm the safety of its oral use.
Subject(s)
Nyctaginaceae/toxicity , Plant Extracts/toxicity , Plant Leaves/toxicity , Administration, Oral , Animals , Bone Marrow Cells/drug effects , Bone Marrow Cells/pathology , DNA, Bacterial/drug effects , DNA, Bacterial/genetics , Dermatitis, Contact/etiology , Dermatitis, Contact/pathology , Eye/drug effects , Eye/metabolism , Eye Proteins/metabolism , Female , Hemolysis/drug effects , Male , Mice, Inbred BALB C , Micronuclei, Chromosome-Defective/chemically induced , Micronucleus Tests , Mutation , Nyctaginaceae/chemistry , Phytotherapy , Plant Extracts/administration & dosage , Plant Extracts/isolation & purification , Plant Leaves/chemistry , Plants, Medicinal , Protein Denaturation , Rabbits , Rats, Sprague-Dawley , Rats, Wistar , Risk Assessment , Skin Irritancy Tests , Solvents/chemistry , Time Factors , Toxicity Tests, AcuteABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: The genus Boerhavia is widely distributed in tropical, subtropical and temperate regions of the world including Mexico, America, Africa, Asia, Indian Ocean Islands, Pacific Islands and Australia. The genus Boerhavia is extensively used by local peoples and medicinal practitioners for treatments of hepatitis, urinary disorders, gastro intestinal diseases, inflammations, skin problems, infectious diseases and asthma. Present review focused on traditional uses, phytochemistry, pharmacology and toxicology of Boerhavia genus to support potential scope for advance ethnopharmacological study. MATERIALS AND METHODS: Information on the Boerhavia species was collected from classical books on medicinal plants, pharmacopoeias and scientific databases like PubMed, Scopus, GoogleScholar, Web of Science and others. Also scientific literatures based on ethnomedicinal surveys, Ph.D. and M.Sc. dissertations, published papers from Elsevier, Taylor and Francis, Springer, ACS as well as Wiley publishers and reports by government bodies and documentations were assessed. RESULTS: A total of 180 compounds from Boerhavia genus were isolated of which B. diffusa alone shared around 131 compounds and for most of which it is currently an exclusive source. In the genus, phenolic glycosides and flavonoids contribute approximately 97 compounds. These includes eupalitin, rotenoids like boeravinones, coccineons, alkaloid i.e. betanin and punarnavine etc., showing vital pharmaceutical activities such as anticancer, anti-inflammatory, antioxidant and immunomodulatory. CONCLUSION: Boerhavia is an important genus with wide range of medicinal uses. However, most of the available scientific literatures have lacked relevant doses, duration and positive controls for examining bioefficacy of extracts and its active compounds. In some studies, taxonomic errors were encountered. Moreover, there is need for accurate methods in testing the safety and ethnomedicinal validity of Boerhavia species.
