12 research outputs found
Estudo fitoquímico de Piper gaudichaudianum e sua interaçao com morcegos frugívoros
Orientadora: Beatriz Helena Lameiro Noronha Sales MaiaTese (doutorado) - Universidade Federal do Paraná, Setor de Ciencias Exatas, Programa de Pós-Graduaçao em Química. Defesa: Curitiba, 2003Inclui bibliografia e anexosÁrea de concentraçao: Química OrgânicaResumo: Este trabalho busca um entendimento químico da relação entre Piper gaudichaudianum e o seu principal consumidor e dispersor de suas sementes, o morcego frugívoro Carollia perspicillata. O estudo foi conduzido no PEVR (Parque Estadual Vila Rica do Espírito Santo), localizado em Fênix - PR. Os morcegos são considerados grandes dispersores de sementes de plantas, exercendo um papel importante na recomposição de ambientes. Este trabalho é pioneiro na área de ecologia química. Para tanto, fez-se o estudo fitoquímico dos frutos imaturos e maduros de P. gaudichaudianum, com o isolamento e a identificação de cinco componentes não voláteis: 5,7-diidroxi flavanona, (pinocembrina); 2,2-dimetil-6-carboxicroman-4-ona ; 2-(2'-hidroxi-5'-metoxifenil)-N-(2''-metilpropenil)-2-oxo-acetamida; (E)-4-(3'-decenil) fenol (gibbilimbol B); 2,2-dimetil-2H-1-benzopirano 6-carboxilato de metila. O composto 2-(2'-hidroxi-5'-metoxifenil)-N-(2''-metilpropenil)-2-oxo-acetamida é inédito como produto natural. Foram feitas algumas reações de microderivatizações para auxiliar na elucidação estrutural do (E)-4-(3'-decenil) fenol. Uma análise circadiana dos componentes voláteis dos frutos imaturos e maduros dessa planta, obtidos via aeração e hidrodestilação foi feita por CG/EM. Testes de campo foram realizados para verificar o papel do óleo essencial na atratividade de morcegos frugívoros C. perspicillata. Estes testes foram conduzidos, utilizando: 1. o óleo essencial bruto de frutos maduros obtidos por hidrodestilação. Os resultados apontaram para uma atratividade positiva de 80,7%. 2. o componente majoritário identificado na amostra de óleo essencial dos frutos maduros noite obtido sinteticamente. O resultado não foi conclusivo. Finalmente, testes de atividade antimicrobiana foram feitos. As substâncias 2,2-dimetil-6-carboxicroman-4-ona e 2-(2'-hidroxi-5'-metoxifenil)-N-(2''-metilpropenil)- 2-oxo-acetamida apresentaram atividade inibitória para os microrganismos Enterococcus faecium, Micrococcus luteus e Staphylococcus faecium. Já as amostras (E)-4-(3'-decenil) fenol e (E)-4-(3'-decenil) metoxibenzeno apresentaram resultado positivo apenas contra Rhodococcus equi. Fica evidente o pioneirismo deste trabalho, no enfoque inédito da interação mutualística planta-morcego frugívoro, aliando-se o aspecto biológico ao aspecto químico dessa interação.Abstract: The present work describes a chemical understanding of the relation between Piper gaudichaudianum and its main consumer and dispersor of your seeds, the frugivorous bat Carollia perspicillata. The study was conducted in the PEVR (Parque Estadual Vila Rica do Espírito Santo), located in Fenix - PR - Brazil The bats are considered the most important seeds dispersor of plants, having an important function in environmental recovery. It's a pioneer work in chemical ecology area. For this purpose, the phytochemical study of the ripe and unripe fruits of P. gaudichaudianum allowed the isolation and identification of five no volatile components: 5,7-dihydroxy flavanone, (pinocembrin); 2,2-dimethyl-6- carboxychroman-4-one; 2-(2'-hydroxy-5'-methoxy-phenyl)-N-(2''-methyl-propenyil)-2- oxo-acetamide; 4-(3'(E)-decenyl) phenol (gibbilimbol B); methyl 2,2-dimethyl-2H-1- benzopyran-6-carboxylate. The component 2-(2'-hydroxy-5'-methoxy-phenyl)-N-(2''- methyl-propenyil)-2-oxo-acetamide is new as natural product. In order to help in identification of structure 4-(3'(E)-decenyl) phenol some reactions of derivatizations was done. A circadian analysis of the volatile components from unripe fruits and ripe fruits of this plant, obtained by headspace and hydrodistillation, was performed by GC/MS. Field trials were done to verify the function of essential oils in the attraction of frugivorous bat C. perspicillata. These trials were conducted with: 1) The essential oil of ripe fruits obtained by hydrodistillation. The result was an significant attractivity value ( 80,7 %). 2) The main component identified in the sample of the essential oil of ripe fruits collected in the night, synthetically obtained. It's not obtained a conclusive result. Along with the phytochemical study, it was also made an antimicrobian activity assays. The substances 2,2-dimethyl-6-carboxychroman-4-one and 2-(2'-hydroxy-5'- methoxy-phenyl)-N-(2''-methyl-propenyil)-2-oxo-acetamide showed inhibitory activity for the microorganisms Enterococcus faecium, Micrococcus luteus and Staphylococcus faecium, while the samples 4-(3'(E)-decenyl) phenol and 4-(3'(E)- decenyl) metoxybenzene showed a positive results only against Rhodococcus equi. It's pioneering work because showed the mutualistic interaction between frugivorous bat and plant, considering the biological and chemical aspects these interaction
Flavonoids: Classification, Biosynthesis and Chemical Ecology
Flavonoids are natural products widely distributed in the plant kingdom and form one of the main classes of secondary metabolites. They display a large range of structures and ecological significance (e.g., such as the colored pigments in many flower petals), serve as chemotaxonomic marker compounds and have a variety of biological activities. Therefore, they have been extensively investigated but the interest in them is still increasing. The topics that will be discussed in this chapter describe the regulation of flavonoid biosynthesis, the roles of flavonoids in flowers, fruits and roots and mechanisms involved in pollination and their specific functions in the plant
CONDENSED TANNINS OF THE SPECIES PINUS TAEDA: EXTRACTION, CHARACTERIZATION AND POTENTIAL FORMULATION OF WOOD BIOADHESIVE
The species Pinus taeda was evaluated as a source of condensed tannins for the potential formulation of phenolic adhesives from the extraction of the wood cortex. Extraction yield, percentage of tannins and non-tannins, and reactivity to the formaldehyde by the Stiasny number were analyzed in the responses of the extraction processes with extractive agents sodium sulfite (Na2SO3), sodium hydroxide (NaOH), and urea [(NH2)2CO] in the percentages of 2, 4, 6, 8, and 10 in relation to the weight of the bark of this species. The extracts were analyzed using the techniques of IR - Infrared Spectroscopy, SEM - Scanning Electron Microscopy, DRX- X-ray Diffractometry, and EDS - Energy-Dispersive X-ray Spectrometry. In another step, the formation time of the commercial tannin gel and of the P. taeda were compared in relation to formaldehyde. The results show that the specie have condensed tannins, and sustain that they are catechins. These catechins form polymers identified by SEM in less time in relation to the formaldehyde in the formation of the gel, suggesting that the tannins can be extracted from the species as a potentially new commercial source that lumber companies can use to manufacture phenolic resins
ELABORAÇÃO E CARACTERIZAÇÃO DE BEBIDAS À BASE DE EXTRATO HIDROSSOLÚVEL DE SOJA COM POLPA DE PITANGA, AMORA E MIRTILO
Atualmente, observa-se uma busca do consumidor por alimentos com elevadas propriedades nutricionais e funcionais, despertando o interesse das agroindústrias por frutas com características exóticas. Este trabalho tem como objetivo o desenvolvimento de bebidas a base de soja nos sabores pitanga, amora e mirtilo. A caracterização das polpas e da bebida foi feita através de análises físico-químicas e microbiológicas, além da aplicação de análise sensorial no produto desenvolvido. Entre as análises físico-químicas de conteúdo mineral, proteínas, sólidos, lipídios e glicídios, o pH foi o descritor que melhor explicou a diferença entre as polpas e as bebidas (Análise de Componentes Principais - ACP). Na realização da análise sensorial das bebidas o índice de aceitação foi satisfatório, indicando potencial para a industrialização das mesmas e necessidade de maior intensificação do aroma e sabor no desenvolvimento do produto final
Investigation on chemical composition and optimization of essential oil obtainment from waste Pinus taeda L. using hydrodistillation
Incorporação de fonte de nitrogênio em partículas de PVA e alginato de sódio e estudo da influência de ciclos de congelamento/descongelamento na caracterização do produto
Neste trabalho foram incorporadas duas fontes de nitrogênio (ureia e caulinita intercalada com ureia) em matriz polimérica de álcool polivinílico e alginato de sódio na proporção de 3:1, utilizando a metodologia de gotejamento em solução de CaCl2. As partículas foram submetidas ao congelamento e posterior descongelamento com o intuito de melhorar a estrutura e resistência térmica da matriz polimérica. As partículas foram caracterizadas através de Análise Elementar, FTIR, DRX e Análise Térmica. As partículas que apresentaram as melhores formulações foram as de álcool polivinílico+alginato de sódio+ureia, pois apresentaram eficiência de incorporação próximas as das partículas de álcool polivinílico+alginato de sódio+caulinita intercalada, mas com maior estabilidade térmica, cerca de 200 °C
Relationship between the amount and composition of epicuticular wax and tolerance of Ipomoea biotypes to glyphosate
Chemical profile and biological properties of the Piper corcovadense C.DC. essential oil
The essential oil from Piper corcovadense D.DC. (EOPc), an important plant belonging to the Piperaceae family, which is commonly found in the northern region of Brazil and poorly explored scientifically, was used in this study. Thus, the EOPc was characterized chemically by Gas Chromatography/Mass Spectrometry (GC/MS) and the antioxidant and antimicrobial activities and their potential effects on cutaneous melanoma (SK-MEL-28) and healthy peripheral blood mononuclear (PBMC) cells were determined. The major compounds identified in the EOPc were: trans-sesquisabinene hydrate, trans-caryophyllene, β-pinene, trans-β-farnesene, 14-hydroxycaryophyllene, limonene and p-cymene. The EOPc demonstrated antioxidant activity as evaluated by Folin-Ciocalteu reagent (FC) reducing capacity, DPPH, and ABTS methods. The values found were respectively 5.41 ± 0.17 mg GAE mL−1 (GAE: Gallic acid equivalent), 2.88 ± 0.17 µmol TE mL−1 (TE: Trolox equivalent) and 6.26 ± 0.02 µmol TE mL−1. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined for different bacterial strains. The EOPc at a concentration of 2.61 µg mL−1 exhibited both bactericidal and bacteriostatic properties against Escherichia coli. The EOPc showed potential antitumor activity as it reduced the cell viability of human cutaneous melanoma cells SK-MEL-28. Besides, the EOPc did not exhibit cytotoxic activity against healthy PBMCs, indicating that it does not harm healthy cells at the tested concentrations. The EOPc increased the levels of ROS at concentrations of 250 µg mL−1. The EOPc also did not stimulate the mobilization of endogenous antioxidant defenses, as assessed by total thiol (PSH) and non-protein thiols (NPSH). Thus, the study suggests that the EOPc has antioxidant and antimicrobial properties due to the presence of specific compounds. It also exhibits antitumor potential against cutaneous melanoma cells while showing no cytotoxicity to healthy PBMCs. It directly influenced ROS levels at the highest tested concentration in the cells, suggesting an antitumor effect related to the intrinsic apoptosis pathway. Nevertheless, while the study has initial findings, the results are promising and indicate an attractive biological potential of P. corcovadense, mainly in human cutaneous melanoma cells