The antimicrobial activity of the hexanic extracts and fractions of fruits of Campomanesia pubescens pubescens (D.C) O. Berg and Campomanesia adamantium (Cambess.) O. Berg were assayed against six microorganisms. The hexanic extracts of C. pubescens and C. adamantium fruits were also investigated in their composition by gas chromatography-mass spectrometry and high-performance liquid chromatography with diode array detection. The results of this study showed the presence of 34 volatile compounds and flavonoids in the hexanic extract of C. pubescens and 33 volatile compounds and flavonoids in the hexanic extract of C. adamantium.
Recebido em 2/9/10; aceito em 16/2/11; publicado na web em 15/4/11 ANALYSIS OF ORGANOCHLORINE PESTICIDES IN WATER USING HEADSPACE SOLID PHASE MICROEXTRACTION WITH GAS CHROMATOGRAPHY AND MASS SPECTROMETRY. A method based on headspace -solid phase microextraction coupled with gas chromatography -mass spectrometry was validated for the quantitative determination of 18 organochlorine pesticides in water. For the extraction conditioning some parameters as the best type of coating fiber, time and temperature of extraction, pH and ionic strength were evaluated. The method HS-SPME/GC-MS/MS showed linear coefficient above 0.9948. The repeatability of the measurements were lower than 7.6%. Relative recoveries were between 88 and 110%. Limits of detection from 0.5 x 10 -3 to 1.0 mg L -1 were obtained. A total of 31 samples were analyzed and 16 presented from 1 to 5 pesticides.Keywords: organochlorine pesticides; HS-SPME/GC-MS/MS. INTRODUÇÃOO setor agrícola vem se esforçando a cada ano para aumentar a produção de alimentos, tanto para o mercado interno quanto para o externo. Porém, por falta de informação ou pelo interesse único no lucro, a produção agrícola contribuiu de forma efetiva para a contaminação das águas, tanto em nível superficial quanto subterrâneo. No distrito de Culturama, localizado na cidade de Fátima do Sul, as culturas temporárias (cana-de-açúcar, soja, mandioca, arroz, feijão e tomate) são predominantes e um grande número de inseticidas e acaricidas são aplicados.3 O uso de pesticidas adquiridos de forma ilegal de países vizinhos (Paraguai e Uruguai) tem sido reportado pela imprensa brasileira, principalmente em alguns estados da Federação, como Rio Grande do Sul, Paraná e Mato Grosso do Sul, devido à proximidade com estes países. Os pesticidas podem ser adquiridos no Paraguai pagando-se até dez vezes menos o valor praticado no Brasil. 4 Pelo fato destes produtos não passarem por um controle de qualidade, não se sabe exatamente a sua composição química e, consequentemente, a concentração que está sendo aplicada, elevando o risco à saúde humana e ao meio ambiente. O Ministério da Agricultura e a Polícia Federal têm intensificado ações para detectar, penalizar e coibir tais práticas.Os organoclorados são compostos sintéticos de cadeia cíclica com baixa massa molecular e pouco solúveis em água e solúveis em solventes orgânicos, o que os torna mais tóxicos e de apreciável absorção cutânea.5 Além da via dérmica, são também absorvidos por via digestiva e respiratória. Devido à grande lipossubilidade e à lenta metabolização, esses compostos se acumulam na cadeia alimentar e no tecido adiposo. A eliminação se faz pela urina e também pelo leite materno.6 Por essas características, os pesticidas organoclorados têm sido progressivamente restringidos ou mesmo proibidos. As primeiras restrições feitas ao seu uso foram ainda na década de 60. O hexaclorobenzeno (HCB) teve sua comercialização proibida em 1983 e neste ano a ANVISA (Agência Nacional de Vigilância Sanitária) divulgou que o endosulfan, por ser considerado ...
Root rot and gummosis caused by Phytophthora spp. are considered one of the most important citrus diseases in Brazil. Symptoms of Phytophora spp. infection in citrus plants are associated with lesions on the bark at the base of the plant, roots, and even lower branches. Inappropriately performed cultural practices, such as excessive irrigation and practices that result in reduced aeration and soil drainage, favor the disease. The objective of this study was to evaluate the effect of Urochloa ruziziensis mulching provided by an ecological mower on the severity of Phytophthora nicotianae root rot and the development of citrus plants and their root system. The experiments were carried out under controlled conditions on Rangpur lime seedlings kept in pots containing soil from ‘Hamlin’ orange orchards with the use of an ecological mower or a conventional mower in the management of inter-row vegetation for six years. Urochloa ruziziensis mulching (9 t ha−1) was added or not to the pots. The inoculation of P. nicotianae in the roots occurred through infection of the soil with a solution containing mycelium and sporangia of the pathogen. A 2 × 2 × 2 factorial scheme was used, with the following factors A: soil type, B: inoculation of P. nicotianae and C: mulching of U. ruziziensis. The attributes of plant development, such as root growth, average number of leaves, leaves and dry mass of shoots and roots, in addition to assessments of the severity of disease in the roots, were evaluated. The mulch of U. ruziziensis did not promote an increase in root rot. The soil resulting from this management promoted the better development of Rangpur lime plants. Therefore, vegetation management between rows with an ecological mower is not associated with increased symptoms of Phytophthora root rot.
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