Licenciatura em Química (Sede)
URI permanente desta comunidadehttps://arandu.ufrpe.br/handle/123456789/26
Siglas das Coleções:
APP - Artigo Publicado em Periódico
TAE - Trabalho Apresentado em Evento
TCC - Trabalho de Conclusão de Curso
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4 resultados
Resultados da Pesquisa
Item Análise da composição química do óleo essencial de espécies de Plectranthus cultivadas sob condições de estresse e avaliação Do seu potencial acaricida sobre o Tetranychus urticae(2024-07-31) Silva, Beatriz Steffanie Gomes da; Moraes, Marcílio Martins de; http://lattes.cnpq.br/6957579091162269; http://lattes.cnpq.br/4696332206790980Plants are living organisms capable of producing secondary metabolites as a defense and development mechanism. What stimulates the activation of secondary metabolism are changes in the natural conditions necessary for the survival of the plant, called biotic or abiotic stresses. Essential oils (EOs) are complex mixtures of constituents originating from the secondary metabolism of plants, and have different biological properties, from medicinal purposes to pest control. Thus, the objective of this study was to investigate the variation in the chemical composition of EOs from two species of the genus Plectranthus (P. barbatus and P. ornatus) under controlled stress conditions and the antioxidant and acaricidal potential against Tetranychus urticae (spotted spider mite). The species were separated into groups and subjected to different stress conditions: manual predation (PM), methyl salicylate (SM), methyl jasmonate (MJ), saline (S), water scarcity (E), ultraviolet radiation (UV), and the group without any stress (control). The EOs were obtained by hydrodistillation and the chemical composition was determined by gas chromatography coupled to mass spectrum (GC-MS). The data were subjected to multivariate analyses (PCA, heatmap and molecular network). The acaricidal activity was evaluated comparatively through the LC90 of the positive control Azamax and the antioxidant activity by the ABTS.+ and DPPH methods. For both species, the chemical composition identified in the control groups showed a predominance of constituents derived from sesquiterpenes, with (E)- caryophyllene as the major constituent. However, in the stressed groups, monoterpenes were present in higher percentages, significantly reducing the percentage of the major compound of the control. This variation was confirmed by all multivariate analyses used. The EOs of both species showed low acaricidal activity against the two-spotted spider mite, with mortality rates equal to 12.00% (P. barbatus) and 22.72% (P. ornatus). P. barbatus showed better antioxidant activity for ABTS.+ (62.74 μg/ml) while P. ornatus showed better for DPPH. (163.5 μg/ml). However, compared to the positive controls Trolox (4.13 μg/ml) and ascorbic acid (1.62 μg/ml), respectively, the activities presented by both species were relatively low. Therefore, it was possible to verify that the EOs of these species present antioxidant and acaricidal activities, although low, and that different stress conditions alter the chemical composition of the plant.Item Composição química, atividade acaricida, propriedade antioxidante, inibição da acetilcolinesterase e toxicidade do óleo essencial das folhas de Sparattanthelium botocudorum(2024-03-05) Silva, Mirian Luzinete da; Camara, Cláudio Augusto Gomes da; http://lattes.cnpq.br/5615678215435460; http://lattes.cnpq.br/4499498152298785Sparattanthelium botocudorum is a species endemic to Brazil, commonly known as “Canela-brava”, this shrub is distributed on the coast of Paraíba and in the state of Pernambuco. Due to the scarcity of chemical and biological studies on this plant, the research aimed to determine the chemical composition of the essential oil of the leaves as well as the evaluation of the acaricidal, antioxidant and toxicity properties against Artemia salina. The essential oil, extracted from fresh leaves, through the hydrodistillation technique with the aid of a Clevenger-type device, had a yield of 0.40% m/m and its chemical characterization, through Gas Chromatography coupled to the Mass Spectrometer (CG-MS), emerged as the majority constituents were the sesquiterpenes Germanecrene D with (38.28 %), E-Nerolidol (18.95 %), [beta]-Caryophyllene (14.49 %) and Biciclogermacrene (14.18 %) and the single monoterpene Z-[beta]-Ocimene identified in the OE with a percentage of 0.37%. Residual contact bioassays were carried out, with the aim of identifying the effects of the oil on the two-spotted mite, and showed promising toxicity. The residual contact bioassay, in which the mites are arranged on already treated leaves, showed LC50 = 16.5 μL/mL. Furthermore, the oil also demonstrated ovicidal properties with an estimated LC50 of 1.20 μL/mL. And regarding repellency activity, the oil showed a better potential with the LC30 concentration 8.8 μL/mL. After evaluating the inhibition activity of the acetylcholinesterase enzyme, the essential oil from the leaves of S. botocudorum inhibited the enzyme, since the LC50 resulted was 2.9 μg/mL below the LC50 of the positive control, which is 5.95 μg/mL. mL. Furthermore, OE presented antioxidant properties for the free radical DPPH˙, estimating an EC50 = 110.3 μg/mL, while for the free radical ABTS˙+ it was EC50 = 49.23 μg/mL. Finally, the oil exhibited a toxicity concentration of 700 μg/mL for the toxicity test against A. salina, which compared to what described in the literature had no toxicity. Therefore, the study showed that the essential oil presented similar and promising effects compared to already commercialized acaricides, and that the bioassays presented different routes of action, therefore acting with different mechanisms on the pest and presenting a biological property of antioxidant activity.Item Avaliação da atividade acaricida de extratos de Spilanthes acmella (Jambú) frente ao Tetranychus urticae e isolamento do Espilantol(2019-06-25) Arrospide, Tainá Melquíades; Nascimento, André Augusto Pimentel Liesen; http://lattes.cnpq.br/8040722729889752; http://lattes.cnpq.br/5103386537312764In this work, the isolation of spilanthol, a bioactive compound present in several plants, among them a Spilanthes acmella (L.), popularly known as "Jambú", was carried out by extraction of post-extraction of the key matter of aerial parts and roots (GC-MS / CG-EM), ultraviolet (UV-Vis) radiation, high performance liquid chromatography (HPLC/CLAE), infrared (IR) chromatography and nuclear magnetic resonance (NMR) compared to the literature. A toxicity of the hexagonal extract of the flowers and leaves of S. acmella was evaluated through laboratory bioassays against the females of Tetranychus urticae Koch, "brindle mite", obtaining LC50 of 1.63 mg / mL. The same extracts were submitted to the repellency test, which verified the preference for foliar veneers of Canavalia ensiformis, "pork bean", based on the described methodology. It was later verified, along with the presence of new molecules and roots of new S. acmella samples also collected in the state of Pará, in order to obtain the same properties of the natural product from new isolations by liquid column chromatography.Item Composição química e atividade acaricida dos óleos essenciais das folhas de Blepharocalyx salicifolius (Kunth) O. Berg e Campomanesia adamantium (Cambss.) O. Berg contra o ácaro rajado (Tetranychus urticae Koch)(2018-07-30) Tenório, Tchiara Margarida Alves; Camara, Cláudio Augusto Gomes da; http://lattes.cnpq.br/5615678215435460; http://lattes.cnpq.br/5453271405325590