Licenciatura em Química (Sede)
URI permanente desta comunidadehttps://arandu.ufrpe.br/handle/123456789/26
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APP - Artigo Publicado em Periódico
TAE - Trabalho Apresentado em Evento
TCC - Trabalho de Conclusão de Curso
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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 Composição química, atividade inseticida e potencial antioxidante dos óleos essenciais das folhas e flores de Plumeria pudica Jacq(2022-09-30) Arcelino, Ariadna Isis Oliveira de; Moraes, Marcílio Martins de; http://lattes.cnpq.br/0321382004671685; http://lattes.cnpq.br/0321382004671685Agricultural producers usually suffer from the attack of pest insects that cause great damage to plantations, among these insects is Plutella xylostella, popularly known as cruciferous moth, as it usually attacks Brassicas plantations, this pest has already caused a global damage of about of US$ 4 billion. Currently, the control of this pest is carried out with commercial insecticides, but the excessive use of these products tends to cause greater resistance of the pest, in addition to contaminating soil, rural workers and mammals. With that, seeing being studied the use of natural products such as extract and essential oil of plants, as an alternative for the control of these agricultural pests, since these materials have in their chemical composition secondary metabolites with high toxicity to insect pests without causing damage to the environment, workers and consumers. The present work analyzed the chemical composition of the essential oil of the leaves and flowers of Plumeria pudica in order to evaluate its chemical composition and insecticidal and antioxidant properties. The analysis by gas chromatography coupled with mass spectrometry (GC-MS) revealed the presence of 8 and 13 compounds in the essential oil of leaves and flowers, respectively. The major compounds identified were (2E)-hexenal (40.67%) and lauric acid (39.97%) for leaves and flowers, respectively. The toxicity bioassay was carried out through residual contact and direct contact with the oil of P. pudica flowers with concentrations of 10μL/mL and 15μL/mL on P. xylostella, for the test using residual contact the oil did not show toxicity, on the other hand, using direct contact, the concentration of 10μL/mL showed a toxicity of 92% and 15μL/mL of 93.10%. In the antioxidant tests it was found that the two oils were active both in the ABTS and DPPH test. In the antioxidant tests, it was found that the oils from the leaves and flowers were active both in the ABTS test and with DPPH. For the acetylcholinesterase (AChE) inhibition test, the oils from the leaves and flowers of P. pudica were used, both oils showed inhibition, and the flower oil showed the closest inhibition to the positive control with an IC50 of 9 .94 mg/ml. The cytotoxicity assay against Artemia salina was also performed with the oils of leaves and flowers with concentrations between 10-100μg/mL and both showed no toxicity.Item Composição química, atividade citotóxica, acaricida e antioxidante do óleo essencial das flores de Caesalpinia echinata (Pau-brasil)(2021-12-10) Rodrigues, Lucas Vitor Batista; Camara, Cláudio Augusto Gomes da; http://lattes.cnpq.br/5615678215435460; http://lattes.cnpq.br/7934872766687903Belonging to the family Fabaceae, Caesalpinia echinata is a tree endemic to Brazil, popularly known as pau-brasil. It was widely explored because of the quality of its wood and the produc-tion of a red pigment and much coveted in colonial times for dyeing fabrics and due to predatory extractivism, it was almost extinct. Currently, wood is much sought after for the manufacture of bows for violins for its ideal stiffness and density. The scarcity of chemical and biological studies of different parts of the plant motivated the chemical composition of the essential oil of the flowers as well as the evaluation of the acaricide, cytotoxicity properties against saline ar-temia and antioxidant. The flowers of C. echinata were collected on the campus of the Federal Rural University of Pernambuco. The essential oil (EO) was extracted from the hydrodistilla-tion technique by a modified Clevenger type apparatus. The chemical composition of the oil was determined by gas chromatography coupled to a mass spectrometer. Residual contact was the method selected to evaluate the acaricide action on Tetranychus urticae and the biological model selected for cytotoxicity evaluation was That of A. salina. The EO of the flowers pre-sented monoterpenes as the main chemical class. The main compounds identified were linalool (32.33%), Z-jasmona (14.94%) and [beta]-E-ocimene (10.44%). The essential oil for the control of T. urticae presented a LC50 = 290.15 uL/mL. The EO revealed an antioxidant capacity for the free radical DPPH˙ estimated at EC50 = 364.10 ug/mL, while for the free radical ABTS˙+ was EC50 = 280.50 ug/mL. The oil exhibited a LC50 = 97.41ug/mL for the toxicity test against A. salina. This study showed that the essential oil of C. echinata flowers has acaricide, antioxidant and cytotoxic biological property against A. salina.Item Identificação química e atividade antimicrobiana de óleos essenciais das folhas de Piper marginatum obtidos em meio ácido, básico e neutro(2019-12-18) Claudino, Líbna Larissa Monteiro; Ramos, Clécio Souza; http://lattes.cnpq.br/3782004073843685; http://lattes.cnpq.br/1342247970543261The increasing resistance of pathogenic microorganisms to conventional antimicrobials has been faced as a worldwide public health problem. The generalized use of antimicrobials in the treatment of infections caused by pathogens indulges microbial resistance, rendering them ineffective. The search for new plant compounds becomes an innovative alternative as an excellent source of new bioactive molecules. This work aims to define the chemical composition, as well as to evaluate the antimicrobial activity of essential oils of Piper marginatum leaves in basic, acid and neutral environments. The collection of plant material was made in the reserve dois irmãos located in the city of Recife on the campus of the Universidade Federal Rural de Pernambuco (UFRPE). The essential oils extracted from Piper marginatum leaves were obtained by hydrodistillation technique, using Clevenger type apparatus and the identification of their chemical constituents were determined by GC-MS. To obtain the oil in acidic environments an acidic solution of sulfuric acid: nitric acid in the molar ratio (1: 1) was prepared, as well as to obtain in basic environments a basic solution of potassium hydroxide was prepared at a concentration of 5 Mol.L-1. Antimicrobial activity was evaluated using the MIC method (Minimum Inhibitory Concentration). The results showed that the oil obtained in acid environments had a better activity against gram-negative E. coli bacteria with a MIC of 78.1 μg/ml and the fungi C. Albicans and C. Utilis with a MIC of 312 μg/ml and 78.1 μg/ml respectively. The activities of oils in basic and neutral environments were considered moderate to weak for all microorganisms tested, and showed MIC ranging from 625 μg/ml to 2500 μg/ml for both oils. Regarding the identification of the constituents, the major compounds found in the oils obtained in the basic and neutral environments were Macrocarpene, and Z Asarone, respectively. These results contribute to the chemical and biological knowledge of P. Marginatum, which is widely publicized as an excellent plant for therapeutic purposes.Item Determinação da composição química do óleo essencial e substâncias voláteis das flores Bauhinia variegata L(2021-12-16) Nascimento, Amanda Laysa Silva; Camara, Cláudio Augusto Gomes da; http://lattes.cnpq.br/5615678215435460Item Composição química e atividade acaricida do óleo essencial das folhas de Syzygium cumini (Myrtaceae)(2021-07-15) Almeida, Alice Mariana Souza de; Camara, Cláudio Augusto Gomes da; http://lattes.cnpq.br/5615678215435460; http://lattes.cnpq.br/5370687315044618Syzygium cumini, known as purple olive, or jamul, dates back to its healing powers since the beginnings of many societies, today confirmed through its antioxidant, anti-diabetic, anti-fungal properties and reports against different arthropods. The essential oil, extracted from the fresh leaves, through hydrodistillation technique with the aid of a Clevenger type apparatus, had a yield of 0.12%m/m and its chemical characterization, through Gas Chromatography coupled to a Mass Spectrometer (GC-MS), provided as major constituents (Z)-[beta]-ocimene (30.456%), [alfa]-pinene (15.537%) and (E)-[beta]-ocimene (15.177%). The contact bioassays performed, with the objective of identifying the effects of the oil on the spider mite, demonstrated a considerable toxicity of the oil. The residual contact bioassay, which the mites are placed on already treated leaves, presented the LC50 = 7.54uL/mL. While in the spray bioassay, where the mites are sprayed when they are on the leaves, presented a LC50 = 8.69uL/mL. In addition, the oil was also showed an ovicidal property with an estimated LC50 of 0.22uL/mL. this essential oilvshowed similar and promising effects compared to acaricides already marketed, while bioassaysvdemonstrated how different tests act on pest instinct mechanisms.Item Montagem de uma aparelhagem com materiais alternativos para a extração do limoneno das cascas de laranja(2022-06-01) Silva Filho, Josué Berto da; Freitas Filho, João Rufino de; http://lattes.cnpq.br/9252404584350850Essential oils are volatile substances and can be obtained through several methods: hydrodistillation, extraction by organic solvents, steam distillation, extraction by supercritical fluid, flowering, cold pressing, among others. This work aimed to investigate the extraction of essential oils from the orange peel using a distillation apparatus assembled with alternative materials and to compare its efficiency with the conventional apparatus used in the laboratory. For the extraction of limonene, the methodology used was the hydrodistillation technique, which is an old and versatile method in which the plant material remains in contact with boiling water, the steam forces the cell walls to open and the oil that is between them evaporates. the plant cells. The proposal to build the material and extract the oil was due to the need to facilitate the teaching and learning of chemistry concepts in high school. The idea of extracting the essential oil from the orange peel was an artifice used to encourage experimental activities at school. Because, when observing an experiment, the student has the opportunity to make an internal reconstruction of everything experienced at that moment. In conclusion, in this work, the construction of a low cost homemade condenser was elaborated, using alternative materials and later the oil extraction where some concepts can be studied, such as boiling point, condensation, evaporation, intermolecular forces, solubility, polarity etc.Item Análise comparativa do potencial inseticida dos óleos essenciais das folhas e frutos de Melaleuca leucadendra sobre a traça das crucíferas (Plutella xylostella)(2019-06-28) Santos, Rodrigo Bastos dos; Camara, Cláudio Augusto Gomes da; http://lattes.cnpq.br/5615678215435460; http://lattes.cnpq.br/3667225401473912The objective of this work is to investigate the insecticidal potential of the essential oils of the different parts of Melaleuca leucadendra, on the cruciferous moth, Plutella xylostella, contributing to the studies aimed at botanical insecticides. To this end, we analyzed comparatively the insecticidal activity of the leaf and fruit oils of M. leucadendra on P. xylostella by means of the larvicide toxicity bioassays and embryocid toxicity, also comparing its results with the insecticide Azamax® Commercial. The OEs obtained for leaves and fruits of M. leucadendra, presented yield of 0.28% ± 0.05 and 0.18% ± 0.03 respectively, being all in acceptable standards for plants producing essential oils. As the majority constituent of these oils, sesquiterpene (E)-nerolidol in concentrations above 90% was characterized in both parts. The results obtained through the larvicide toxicity Bioassay showed a lethal mean concentration of 0.15 mg/mL and 0.17 mg/mL for the oils of the fruits and leaves of M. leucadendra, respectively, but not statistically different. For the experiments carried out on the embryonic phase of P. xylostella, again there was no statistical difference, showing LC50 of 0.23 mg/mL and 0.28 mg/mL for leaf and fruit oils, respectively. Both essential oils, as well as the majority constituent, presented higher toxicity on the cruciferous moth than the commercial insecticide Azamax® (LC50 = 2,75 mg/mL and LC50 = 2,57 mg/mL on the larvae and eggs, respectively), showing promising in the control of the Plutella xylostella.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