Study of the occurrence of agrochemicals in the waters of the Marombas River- Santa Catarina - Brazil

The region of the sub-basin of the Marombas River is based on economic agroforestry activities. These activities use agrochemicals that can contaminate surface and groundwater and cause diseases in humans and animals. The present study aimed to detect the presence of agrochemicals in the waters of the Marombas River at 4 different points. The water samples were collected every two months over a 1-year period. The concentrations of carbamates, herbicides, fungicides and organophosphates were analyzed. The chromatographic analysis revealed the presence of the fungicide Azoxystrobin (0.65 μg L-1) in the water sample collected at a point in the river with a strong influence of agricultural activities. The concentration of other agrochemicals was below the detection limit of the assay methods used at all points, and in all types of sampling. The Marombas River is subject to contamination by agrochemicals, which represents a potential risk to the human population and to the aquatic biota

Chemical composition similarity between the essential oils isolated from male and female specimens of each five Baccharis species

In the few studies published on essential oils from female and male specimens of Baccharis species, strong differences between the compositions of both samples were always found. The experiments conducted in this study make use of strategies to minimize the interference from genetic and environmental factors. Essential oils from leaves of female and male specimens of five Baccharis species were investigated by gas chromatography-mass spectrometry plus flame ionization detector (GC-MS-FID): B. caprariaefolia and B. dracunculifolia, which have been previously studied with similar aims; and B. coridifolia, B. semiserrata var. elaegnoides and B. pentaptera, the latter two not yet mentioned in the literature. The results were followed by hierarchical cluster analysis, verifying the formation of groups indicative of the great similarity of essential oils from male and female specimens of all five species. The study reinforces the value of field observation in natural product research and points genetic and ecological factors as main responsible for differences in the secondary metabolites of the studied plants._________________________________________________________________________________________ RESUMO: Nos poucos estudos publicados comparando óleos essenciais de espécimes femininos e masculinos de espécies Baccharis, fortes diferenças entre as composições de ambas as amostras foram sempre encontradas. Os experimentos realizados nesta pesquisa utilizam estratégias para minimizar a interferência de fatores genéticos e ecológicos. Os óleos essenciais das folhas de espécimes femininos e masculinos de cinco espécies Baccharis foram pesquisados com uso de um cromatógrafo gasoso acoplado a um espectrômetro de massas e a um detector de ionização de chama (CG-EM-DIC): B. caprariaefolia e B. dracunculifolia, já pesquisadas anteriormente com objetivos similares; e B. coridifolia, B. semiserrata var. elaegnoides e B. pentaptera, as duas últimas ainda não mencionadas na literatura química. Os resultados foram acompanhados por análise hierárquica de grupos, verificando-se a formação de grupos indicativos da grande similaridade entre óleos essenciais dos espécimes masculinos e femininos de todas as cinco espécies. O estudo reafirma o valor das observações de campo na pesquisa de produtos naturais, e aponta fatores genéticos e ecológicos como principais responsáveis por diferenças no metabolismo secundário das plantas estudadas