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1.
Environ Monit Assess ; 193(12): 809, 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34783906

RESUMO

The use of biodiesel blends with petroleum diesel in vehicular engines demands the evaluation of the possible impacts and effects of the gases emitted from their combustion on the environment. Among studies on these questions, biomonitoring using lichens is a viable alternative, given their interactions with the elements dispersed in the atmosphere, as well as its sensitivity and capacity to retain contaminants. In this study, we analyzed the effects of gas emissions from the combustion of biodiesel mixture with petroleum diesel on Cladonia verticillaris thalli. Samples of the lichen (10 g) were exposed to the gases emitted by the exhaust of the generator engine during the combustion process of biodiesel mixtures to petroleum diesel (7% (B7), 10% (B10), 40% (B40), 50% (B50), and 70% (B70)). At 90 days after exposure, samples were analyzed for n-alkane profiles, thallus morphology, photosynthetic pigment contents, and secondary lichen metabolites (protocetraric and fumarprotocetraric acids). Sets B7 and B10 showed better resistance of the lichen to pollutants. Set B40 showed a high stress evidenced by the chain elongation of n-alkanes structure and high chlorophyll production, presenting high morphological damages when compared to the control sets, B7 and B10. The results showed significant reductions of n-alkanes profiles for mixtures with high concentrations of biodiesel (B50 and B70), as well as decreases in the chlorophyll content. These groups showed an increase in the synthesis of secondary metabolites, corroborating the hypothesis that high concentrations of biodiesel in the mixture with petroleum diesel have greater impacts on the lichen. Schematic model for demonstration of using the lichen Cladonia verticillaris as biomonitor of effects from gas emissions from the combustion of biodiesel blends with petroleum diesel by a stationary engine.


Assuntos
Biocombustíveis , Líquens , Ascomicetos , Biocombustíveis/análise , Conservação dos Recursos Naturais , Monitoramento Ambiental , Gasolina/análise , Emissões de Veículos/análise
2.
An Acad Bras Cienc ; 88(3): 1431-7, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27508993

RESUMO

Mangroves represent areas of high biological productivity and it is a region rich in bioactive substances used in medicine production. Conocarpus erectus (Combretaceae) known as button mangrove is one of the species found in mangroves and it is used in folk medicine in the treatment of anemia, catarrh, conjunctivitis, diabetes, diarrhea, fever, gonorrhea, headache, hemorrhage, orchitis, rash, bumps and syphilis. The present study aimed to investigate the acute toxicity of aqueous extract of leaves of C. erectus in Swiss albino mice. The plant material was collected in Vila Velha mangroves, located in Itamaracá (PE). The material was subjected to a phytochemical screening where extractive protocols to identify majority molecules present in leaves were used. The evaluation of acute toxicity of aqueous extract of C. erectus followed the model of Acute Toxicity Class based on OECD 423 Guideline, 2001. The majority molecules were identified: flavonoids, tannins and saponins. The LD50 was estimated at 2,000 mg/kg bw. Therefore, the aqueous extract showed low acute toxicity classified in category 5.


Assuntos
Myrtaceae/toxicidade , Extratos Vegetais/toxicidade , Folhas de Planta/toxicidade , Áreas Alagadas , Animais , Flavonoides/análise , Flavonoides/toxicidade , Masculino , Camundongos , Myrtaceae/química , Compostos Fitoquímicos , Folhas de Planta/química , Saponinas/análise , Saponinas/toxicidade , Taninos/análise , Taninos/toxicidade , Testes de Toxicidade
3.
Chem Biodivers ; 12(8): 1271-80, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26265579

RESUMO

Circumscriptions for the Sapindaceae family and its infrafamilial relationships have been widely discussed. Certain groups are highly morphologically similar; thus, it is difficult to identify certain taxa. DNA Analyses have also indicated complex phylogenetic relationships, and it is difficult to relate such analyses to morphological data. Given the above concerns, this study aimed to investigate the fatty-acid profiles of the seed oils of 16 Sapindaceae species belonging to five tribes and to evaluate their potential chemotaxonomic significance. In total, eleven fatty acids were identified, and eicosenoic acid predominated in nine species. Multivariate analyses (principal component and cluster analyses) of the fatty-acid profiles of the seed oils allowed to separate them in two major clusters. The first cluster, characterized by oils with high eicosenoic acid levels, included all species belonging to the Paullinieae tribe (Cardiospermum, Paullinia, and Serjania species). In the second main cluster, the chemical similarity of the oils was lower, and the species belonged to different tribes. Nevertheless, the tree investigated Allophylus species (Thouinieae tribe) constituted a separate subcluster. Thus, the results showed that the fatty-acid composition of the seed oils of Sapindaceae species provide chemotaxonomic support for the separation of the Paullinieae tribe from the other tribes studied.


Assuntos
Ácidos Graxos/análise , Óleos de Plantas/química , Sapindaceae/química , Sementes/química , Análise por Conglomerados , Análise Multivariada , Óleos de Plantas/classificação , Análise de Componente Principal , Sapindaceae/classificação , Sementes/classificação
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