Otimização de método para analise de tebutiurom, diurom e seus produtos de degradação em água superficial

In 2001, it was estimated that pesticide used worldwide exceeded 2.27 billion kilograms, over 35%, of which, were herbicides. Brazil is considered one of the leaders in the production of sugarcane and mainly ethanol as fuel. The monoculture of sugarcane requires the usage of a range of pesticides, among these, the herbicides diuron and tebuthiuron. The degradation products most studied (DCA and DCPU) are diuron's, especially for toxicological characteristics of this herbicide that is identified as carcinogen and suspected to be endocrine disruptor in mammals. After optimization of the chromatographic separation using HPLC-UV, the analytical curve was constructed in solvent and subsequently in the matrix (surface water). The extraction method contains the usage of SPE (solid phase extraction) (Strata-X, 200 mg/6 mL), applicating 1L of sample and elution with 5 mL of acetonitrile / methanol (50:50, v/v). Analysis by HPLC/UV was performed in gradient mode, acetonitrile/water (70/30-74/26 by 1 min, 74/26 - 78/22 till 3.2 min, returning to initial conditions and remaining this way until 10 min), 018 column (Phenomenex, 4.6 mm diameter, 250 mm long and 5pm particle size) and detection at 254 nm. Tests F and t were performed to verify the presence of the matrix effect. There was matrix effect to all analytes, ranging from -33% (DCA) and 38% (tebuthiuron). Thereby the method was optimized and validated for analysis of diuron, tebuthiuron, and DCPU DCA in surface water using HPLC/UV. The data obtained show that in order to assure the analytical reliability desired the use of the analytical curves in the matrix for the quantification of these analytes in water is required.

Investigação dos efeitos tóxicos, citotóxicos, genotóxicos e mutagênicos do inseticida Curbix® 200SC (ethiprole) em organismos não alvos

Pós-graduação em Ciências Biológicas (Biologia Celular e Molecular) - IBRC

Seletividade de inseticidas ao parasitoide de ovos Trichogramma pretiosum (hymenoptera: trichogrammatidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Determinação do teor dos ingredientes ativos imidacloprida e clorpirifós em produtos técnicos formulados por CLUE-DAD

The use of pesticides to manage pest problems in agriculture has become a common practice around the world. Pesticides consist in chemical substances or biological agents that act preventing, destroying, repelling or mitigating the damage caused by pests in agriculture. In order to a successful treatment, the correct dosage of pesticide has to be applied for each kind of culture. In this context, this project aims to quantify the levels of the active ingredients Imidacloprid and Chlorpyrifos present in formulated technical products and compare with the reported in the ir commercial leaflets. The analyzes were performed by Ultra Performance Liquid Chromatography coupled to a photodiode array detector (CLUE-DAD). The identification of Imidacloprid and Chlorpyrifos in the samples was realized by comparison of the time of retention and UV spectre of those substances with the commercials patterns, resulting in a excellent method specificity of the method. In the scope of determination of active ingredients in formulated products, the method developed showed good sensitivity in the applied conditions, with suitables limits of detection (4,2.10-² mg L-¹ for Imidacloprid and 1,1.10-¹ mg L-¹ to Chlorpyrifos) and quantitation (1,4.10-¹ mg L-¹ and Imidacloprid 3,6.10-¹ mg L-¹ to Chlorpyrifos) for the concentrations found in matrices analyzed. Furthermore, good results were obtained to the method accuracy with coeficiente of variance values in the range of 0,6 to 0,7% for repeatability (intra-day) and 0,4 to 0,58% for intermediate precision (inter- day). The accuracy of the method was determined by recovery tests, the values were comprised in the range of 98 102%. According to the recommendations of the Associação Brasileira de Normas Técnicas, these values show good accuracy of the method. The concentrations obtained in the quantification of the active ingredients in formulated products showed values within permited by ABNT, 60.1% (w/v) ± 0.6%...

Avaliação da capacidade de renovação do epitélio do mesêntero e seus efeitos no potencial reprodutivo de fêmeas adultas de Ceraeochrysa claveri (Neuroptera: Chrysopidae) alimentadas durante a fase larval com óleo de nim (azadirachta indica A. JUSS)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise histopatológica de fígado de tilápias (Oreochromis Niloticus) expostas ao herbicida 2,4-D comercial

The action of man has led, over the years, major impacts on the environment, especially in aquatic ecosystems, leading to an impairment of water quality, considered one of the essential factors for the maintenance of vital functions and consequently the life of the planet. Among the activities considered a risk for the environment are linked to pollution from many sources and even entire watersheds, whether by industrial waste, sewage, or for substances used in agriculture, such as pesticides, herbicides and fertilizers. The (2,4-D) 2,4- dichlorophenoxyacetic acid is used worldwide, and the fact that its genotoxicity is proven by several studies and by its long persistence in soil, which enables the leaching and percolation of compounds affecting water bodies, toxicity studies are relevant and justifiable. Thus, this study aimed to evaluate the toxicity of 2,4-D by examining the liver of the fish Oreochromis niloticus exposed to different dilutions. Portions of liver were collected and fixed for histological and histochemical techniques to detect total proteins, polysaccharides and lipids. lipids. Treatment with 2,4-D herbicide apparently did not alter the lipid profiles, the accumulation of polysaccharides, and the presence of total proteins. The 2.5 and 5.0% were lethal to fish. These mortalities are probably of high toxic and cytotoxic potential of 2,4-D herbicide results. Several histopathological changes were found, such as: loss of cytoplasmic integrity, loss of cell limit, nuclear deformation, vacuolated cytoplasm, tissue disorganization and hydropic degeneration. Statistically significant changes were: hydropic degeneration and vacuolated cytoplasm. It is concluded, therefore, that the qualitative morphological analysis is an important method for observing changes in liver toxicology studies. As the O. niloticus species is an efficient biological indicator of water pollution by 2,4-D

Investigação dos métodos de separação, uso e aplicação da Lignina proveniente da biomassa lignocelulósica

This study investigated the main methods of separation of components of lignocellulosic biomass, with an emphasis on obtaining lignin and its application. The work was developed based on the concept of Biorefinery proposing full use of renewable raw materials and / or the use of lignocellulosic agricultural residues by biochemical or biotechnological conversion in obtaining high value added products with minimal environmental impact. From this premise, a literature review was performed in refereed journal articles and theses in order to gather enough material for critical analysis of usual and alternative methods in the literature. When researching methods that add value to lignin, it was found that with the technology found today, the cost required to have a degree of competitiveness is still too high, preventing much of the process. However, the isolated lignin can be used as raw material in the production of numerous types of biocomposites and polymers and other products such as phenols, benzene, dispersants, vanillin, emulsifying agents, antioxidants, pesticides, fertilizers, charcoal, concrete additives, among others. As an industrial production level is necessary, because the consumption of biomass will only grow over the years, it is necessary that new methods or technologies to be created in order to facilitate the extensive use of lignocellulosic biomass