RESUMO
Heliotropium taltalense is an endemic species of the northern coast of Chile and is used as folk medicine. The polyphenolic composition of the methanolic and aqueous extract of the endemic Chilean species was investigated using Ultrahigh-Performance Liquid Chromatography, Heated Electrospray Ionization and Mass Spectrometry (UHPLC-Orbitrap-HESI-MS). Fifty-three compounds were detected, mainly derivatives of benzoic acid, flavonoids, and some phenolic acids. Furthermore, five major compounds were isolated by column chromatography from the extract, including four flavonoids and one geranyl benzoic acid derivative, which showed vascular relaxation and were in part responsible for the activity of the extracts. Since aqueous extract of H. taltalense (83% ± 9%, 100 µg/mL) produced vascular relaxation through an endothelium-dependent mechanism in rat aorta, and the compounds rhamnocitrin (89% ± 7%; 10-4 M) and sakuranetin (80% ± 6%; 10-4 M) also caused vascular relaxation similar to the extracts of H. taltalense, these pure compounds are, to some extent, responsible for the vascular relaxation.
Assuntos
Aorta/metabolismo , Extratos Vegetais/química , Polifenóis , Vasodilatação/efeitos dos fármacos , Animais , Heliotropium/química , Masculino , Polifenóis/química , Polifenóis/farmacologia , Ratos , Ratos Sprague-DawleyAssuntos
Adjuvantes Imunológicos/farmacologia , Doenças dos Peixes/imunologia , Infecções por Piscirickettsiaceae/imunologia , Extratos Vegetais/farmacologia , Salmão/imunologia , Animais , Vacinas Bacterianas/imunologia , Doenças dos Peixes/tratamento farmacológico , Doenças dos Peixes/microbiologia , Heliotropium/química , Piscirickettsia , Extratos Vegetais/imunologia , Terpenos/imunologia , Terpenos/farmacologiaRESUMO
The flavonoid 3,5-dihydroxy-7-methoxyflavanone ((-)-alpinone) isolated from sticky resinous exudate of Heliotropium huascoense was evaluated as immunostimulatory in mammalian cells . Preliminary observations had showed that (-)-alpinone had increased the expression levels of pro-inflammatory cytokine transcripts in salmonid. Due to high morbidity and mortality that infectious diseases cause in humans, we evaluate the effect of (-)-alpinone as an immunostimulant in mammalian cells. Reactive oxygen species (ROS) are produced by macrophages activators for the destruction of pathogens; we evaluated (-)-alpinone effect in ROS generation and the proliferation of macrophages. The results showed that proliferation in Raw 264.7 cells treated with 10 and 25 µg/mL of (-)-alpinone had a significant increase in macrophage proliferation. In relation to ROS formation, cells treated with 1 and 5 µg/mL of (-)-alpinone, induce ROS formation in macrophages.
El flavonoide 3,5-dihidroxi-7-metoxiflavanona ((-)-alpinona) aislado del exudado resinoso de Heliotropium huascoense se evaluoÌ como inmunoestimulador en ceÌlulas de mamiÌferos. Resultados preliminares habiÌan demostrado que (-)-alpinona aumentaba los niveles de expresioÌn de transcritos de citoquinas proinflamatorias en salmoÌnidos. Debido a la alta morbilidad y mortalidad que causan las enfermedades infecciosas en los humanos, evaluamos el efecto de (-)-alpinona como inmunoestimulante en ceÌlulas de mamiÌferos. Dado que las especies de oxiÌgeno reactivo (ROS) son producidas por macroÌfagos activados para la destruccioÌn de patoÌgenos, se evaluoÌ el efecto de (- )-alpinona en la generacioÌn de ROS y la proliferacioÌn de macroÌfagos. Los resultados mostraron que la proliferacioÌn en ceÌlulas Raw264.7 tratadas con 10 y 25 µg / mL del flavonoiÌde tuvo un aumento significativo en la proliferacioÌn de macroÌfagos. En relacioÌn con la formacioÌn de ROS, las ceÌlulas tratadas con 1 y 5 µg/mL de (-)-alpinona, inducen la formacioÌn de ROS en los macroÌfagos.
Assuntos
Resinas Vegetais/farmacologia , Flavonoides/farmacologia , Heliotropium/química , Fatores Imunológicos/farmacologia , Mamíferos , Sais de Tetrazólio , Células Cultivadas , Espécies Reativas de Oxigênio , Proliferação de Células/efeitos dos fármacos , Macrófagos/metabolismoRESUMO
In this communication the antibacterial activity of filifolinol (1), naringenin (2) 3-O-methylgalangin (3) and pinocembrin (4) isolated from the resinous exudates of Heliotropium filifolium and H. sinuatum, were evaluated by flow cytometry against Staphylococcus aureus and Salmonella tiphymurium. The results showed that filifolinol (1) and naringenin (2) were inactive in the range of concentrations used (10 to 1000 ug/mL). On the other hand, pinocembrin (4) produced a decrease in cell surface at 500 ug/mL and the total disappearance of both bacterial populations at 1000 ug/mL. Also, 3-O-methylgalangin (3) showed the total disappearance at 1000 ug/mL of both bacterial populations and a decrease at 200 μg/mL for S. typhimurium and at 500 μg/mL for S. aureus.
En esta comunicación, la actividad antibacteriana de filifolinol (1), naringenina (2), 3-O-methylgalangina (3) y pinocembrina (4) aislados de los exudados resinosos de Heliotropium filifolium y H. sinuatum, fueron evaluados por citometría de flujo frente a Staphylococcus aureus y Salmonella tiphymurium. Los resultados mostraron que filifolinol (1) y naringenina (2) fueron inactivos en el intervalo de concentraciones usadas (10 a 1000 μg / mL). Por otro lado, pinocembrina (4) produce una disminución de la superficie de las células a 500 ug/mL y la desaparición total de ambas poblaciones bacterianas a 1.000 ug/mL. También, 3-O-metilgalangina (3) mostró la desaparición total a 1.000 ug / mL tanto de ambas poblaciones de bacterias y una disminución a 200 ug/mL para S. typhimurium y en 500 μg/mL para S. aureus.
Assuntos
Antibacterianos/farmacologia , Heliotropium/química , Óleos Voláteis/farmacologia , Salmonella typhimurium , Staphylococcus aureus , Citometria de Fluxo , Monoterpenos/farmacologia , Exsudatos de Plantas/farmacologia , Sesquiterpenos/farmacologiaRESUMO
The intracellular bacteria Piscirickettsia salmonis is the most prevalent pathogen in the Chilean salmon industry, responsible for 50 percent of losses in recent years. So far, there are no effective treatments to control infections by this pathogen due to the emergence of antibiotics resistance. Therefore, it is extremely important to conduct research to find successful antibacterial therapies. In this paper, we evaluated the in vitro bactericidal activity of flavonoids and aromatic geranyl derivatives isolated from the resinous exudate of species Heliotropium filifolium, H. sinuatum y H. huascoense. The results showed that the compounds Filifolinone, Naringenine and 3-O- methylgalangine cause different percentage of mortality of bacteria and therefore they are good candidates to continue its evaluation in vitro and in vivo.
La bacteria intracelular Piscirickettsia salmonis es el patógeno de mayor incidencia en la industria salmonera chilena siendo responsable de un 50 por ciento de las pérdidas en los últimos años. Hasta ahora no hay tratamientos efectivos para este patógeno que permitan controlar las infecciones provocadas por él debido a la aparición de resistencia a antibióticos. Por lo tanto, resulta de gran importancia investigar para encontrar terapias antibacterianas efectivas. En este trabajo nosotros evaluamos la actividad bactericida in vitro de flavonoides y derivados aromáticos geranilados aislados desde el exudado resinoso de las especies vegetales Heliotropium filifolium, H. sinuatum y H. huascoense. Los resultados mostraron que los compuestos Filifolinona, Naringenina y 3-O-metilgalangina provocan diferentes porcentajes de mortalidad de la bacteria y, por lo tanto, son candidatos para seguir siendo evaluados tanto in vitro como in vivo.
Assuntos
Antibacterianos/farmacologia , Heliotropium/química , Piscirickettsia , Extratos Vegetais/farmacologia , Salmão , Flavonoides/farmacologiaRESUMO
The composition of the essential oil (EO) obtained by hydro distillation from dry leaves of Heliotropium stenophyllum (Heliotropiaceae) was analyzed using gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The insecticidal activity of the oil against the house fly Musca domestica was evaluated and the dose necessary to kill 50 percent of flies (LC50) in 2 h was determined at 25 +/- 1 °C. The essential oil from Heliotropium stenophyllum showed potent insecticidal properties (LC50 = 1.09 mg/dm3) in comparison with other essential oils, in which at shorter times, the same bio-assay was used. According to GC and GC/MS analysis, junenol (19.08 percent); longiborneol (9.34 percent); (E, Z)-geranyl linalool (6.81 percent); selina-3,11-dien-6-alpha-ol (6.70 percent); alpha-cedrene epoxide (6.60 percent); heliofolen-12-al D (6.23 percent) and beta-epi-bisabolol (4.83 percent were the principal components of the EO. The Heliotropium stenophyllum essential oil, made up exclusively of sesquiterpenes, showed a composition very different from the EOs of the other species of Heliotropium, studied, and present a great potential as a natural insecticide against houseflies.
La composición del aceite esencial (AE) obtenido por hidrodestilación de hojas secas de Heliotropium stenophyllum (Heliotropiaceae) se analizó mediante cromatografía de gases (CG) y cromatografía de gases/espectrometría de masas (CG/EM). La actividad insecticida del aceite contra la mosca doméstica Musca domestica se evaluó y la dosis necesaria para matar el 50 por ciento de las moscas (LC50) en 2 h se determinó a 25 +/- 1 ºC. El aceite esencial de Heliotropium stenophyllum mostró potentes propiedades insecticidas (LC50 = 1,09 mg/dm3) en comparación con otros aceites esenciales, en el que en tiempos más cortos, se utilizó el mismo bio-ensayo. De acuerdo con los análisis de CG y CG/EM, junenol (19,08 por ciento); longiborneol (9,34 por ciento), (E, Z)-geranil linalool (6,81 por ciento); selina-3,11-dien-6-alfa-ol (6,70 por ciento); epoxido de alfa-cedreno (6,60 por ciento); heliofolen-12-al D (6,23 por ciento) y beta-epi-bisabolol (4,83 por ciento) fueron los componentes principales identificados en el AE. El aceite esencial de Heliotropium stenophyllum, formado exclusivamente por sesquiterpenos, mostró una composición muy diferente al de los AEs de otras especies de Heliotropium, estudiadas, y muestra un gran potencial como insecticida contra la moscas doméstica.
Assuntos
Óleos Voláteis/química , Extratos Vegetais/química , Heliotropium/química , Inseticidas/química , Bioensaio , Dípteros , Extratos Vegetais/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Inseticidas/farmacologia , Pressão de VaporRESUMO
The antioxidant activity of resinous extracts obtained from H. stenophylum and H. sinuatum species, was evaluated through ORAC index (Oxygen Radical Absorbance Capacity) in water phase and in presence of Triton X-100 micelles, using as test molecules to pyrogallol red (PGR) and evaluating their reduction by the action of peroxyl radicals obtained from thermolysis of AAPH. The results show that these extracts protect to PGR of the action of the radicals. This protection is reduced drastically in the presence of Triton X-100 micelles. The same effect was observed with the main flavonoid of these extracts (3-O-methylgalangin). These results show the importance of the media of reaction of pure compounds and/or extracts at the time of to take into account their use as antioxidants.
La actividad antioxidante de exudados resinosos obtenidos desde las especies H. stenophylum y H. sinuatum, fue evaluada a través del ensayo ORAC (Oxygen Radical Absorbance Capacity) en fase acuosa y en presencia de micelas de Triton X-100, usando como molécula prueba a pirogalol rojo (PGR) y evaluando su reducción frente a la acción de radicales peróxidos obtenidos desde la termólisis de AAPH. Los resultados muestran que estos extractos protegen al PGR de la acción de los radicales. Esta protección es reducida drásticamente en presencia de micelas de Tritón X-100. El mismo efecto fue observado con el flavonoide mayoritario de estos extractos (3-O-metilgalangina). Estos resultados muestran la importancia de considerar el medio de reacción de compuestos puros y/o extractos al momento de tomar en cuenta su uso como antioxidantes.
Assuntos
Antioxidantes/química , Flavonoides/química , Heliotropium/química , Resinas Vegetais/química , Espécies Reativas de Oxigênio/química , MicelasRESUMO
The infectious salmon anemia virus (ISAV) of Orthomyxoviridae family, is responsible for heavy losses in industry aquaculture around the world, affecting several commercial aquatic organisms, mainly Salmo salar. Therefore, it is important to find effective antiviral therapies. In this work we evaluated in vitro and in vivo the antiviral activity of three natural flavonoids isolated from the resinous exudates of the plant Heliotropium sinuatum (Heliotropiaceae) against ISAV. The results show that 7-O-methyleriodictyol was able to inhibit the infectivity of ISAV in vitro assay with EC 50 of 0.20 ug/mL. Despite having a citotoxicity expressed as CC50 of 12.80 ug/mL, the in vivo study showed that this compound protected 100 percent to the fish infected with ISAV keeping 100 percent fish viability. These results allow the proposal of 7-O-methyleriodictyol as a good candidate to be used as antiviral therapy for ISAV in salmon industry.
El virus de la anemia infecciosa en salmón de la familia Orthomyxoviridae, es el responsable de grandes pérdidas en la industria acuícola alrededor del mundo, afectando diversas especies acuáticas comerciales, principalmente Salmo salar. Por lo tanto, es muy importante encontrar una terapia antiviral efectiva. En el presente trabajo, evaluamos la actividad antiviral in vitro e in vivo de tres flavonoides naturales aislados desde el exudado resinoso de la especie vegetal Heliotropium sinuatum (Heliotropiaceae) contra ISAV. Los resultados mostraron que 7-O-metileriodictiol inhibió la infectividad de ISAV in vitro con un EC50 de 0.20 ug/mL. A pesar de tener una citotoxicidad expresada como un CC50 de 12.80 ug/mL, el estudio in vivo mostró que este compuesto protege en un 100 por ciento a los peces infectados con ISAV manteniendo un 100 por ciento de viabilidad. Estos resultados permiten proponer que 7-O-metileriodictiol es un buen candidato para ser usado como terapia antiviral para ISAV en la industria salmonera.
Assuntos
Animais , Antivirais/farmacologia , Extratos Vegetais/química , Flavonoides/isolamento & purificação , Heliotropium/química , Isavirus , Salmão , Aquicultura , Doenças dos Peixes/tratamento farmacológico , Flavonoides/farmacologiaRESUMO
The in vitro effect of the 3 H-spiro [1-benzofuran-2,1-ciclohexane] derivative (Filifolinone), was evaluated on mouse dendritic cells through the level of expression of MHC molecules class II by flow cytometry. The results show that Filifolinone increases the expression of MHC promoting maturation of dendritic cells. The results suggest that Filifolinone is a potential immunomodulator for veterinary use.
La actividad in vitro del derivado 3H-espiro [1-benzofurano-2,1-ciclohexano] (Filifolinona), fue evaluado en células dendríticas de ratón a través del nivel de expresión de moléculas MHC clase II utilizando citometría de flujo. Los resultados muestran que Filifolinona incrementa la expresión de MHC promoviendo la maduración de las células dendríticas. Estos resultados permiten sugerir que Filifolinona es un potencial inmunomodulador de uso veterinario.
Assuntos
Animais , Feminino , Camundongos , Benzofuranos , Células Dendríticas , Heliotropium/química , Fatores Imunológicos , Compostos de Espiro , Citometria de Fluxo , Camundongos Endogâmicos BALB CRESUMO
Careful reevaluation of the 1H and 13C NMR spectroscopic data of filifolinol acetate (4) led to the reassignment of the C-10 and C-11 signals, as well as the gem-dimethyl signals. Single crystal X-ray analysis provided an independent structural confirmation of 4, and comparison of the experimental vibrational circular dichroism spectrum with calculations performed using density functional theory provided the absolute configuration of this 3H-spiro-1-benzofuran-2,1'-cyclohexane and related molecules.
Assuntos
Benzofuranos/química , Cicloexanos/química , Heliotropium/química , Compostos de Espiro/química , Modelos Moleculares , Estrutura Molecular , Epiderme Vegetal/químicaRESUMO
The in vitro effect of the resinous exudate of Heliotropium filifolium, of the 3 H-spiro[1-benzofuran-2,1 '-cyclohexane] derivative called filifolinol 1, isolated from the resin and the semi-synthetic compounds filifolinone 2 and filifolinoic acid 3, obtained from filifolinol 1, were evaluated on the proliferation of an immortalized cell line, UCHT1, derived from rat thyroid. We evaluated the effect of these compounds on UCHT1 cell growth parameters by calculating doubling time; and toxicity using the LIVE/DEAD in vitro test. The results showed that the resin is not active, while filifolinone 2, filifolinoic acid 3 and filifolinol 1 produced a significant inhibition of cell doubling time, in concentrations equal or greater than 50, 25 and 75 uM, respectively. The LIVE/DEAD test showed no significant toxicity at these concentrations, compared to cultures kept in absence of compounds. These results suggest a possible cytostatic effect of these compounds, and could therefore constitute potential alternatives for antineoplasic therapy.
Se evaluó el efecto in vitro de la resina aislada desde Heliotropium filifolium y del derivado 3 H-spiro[1-benzofuran-2,1'-cyclohexano] llamado filifolinol 1, obtenido desde este exudado resinoso y los compuestos semi-sintéticos filifolinona 2 y ácido filifolinoico 3, obtenidos a partir de filifolinol 1, sobre la proliferación de la línea celular inmortal, UCHT1, derivada de tumor de tiroide de rata. Evaluamos el efecto de estos compuestos en el desarrollo celular de UCHT1 a través de los parámetros tiempo de doblaje y citotoxicidad usando el test LIVE/DEAD in vitro. Los resultados mostraron que la resina no presentó actividad y que filifolinona, ácido filifolinoico y filifolinol producen una inhibición significativa del tiempo de doblaje celular, en concentraciones iguales o superiores a 50, 25 y 75 uM, respectivamente. El test LIVE/DEAD no mostró toxicidad significativa en comparación con los cultivos mantenidos en ausencia de compuestos. Estos resultados sugieren un posible efecto citostático de estos compuestos y por lo tanto, constituirían alternativas potenciales para terapia antineoplásica.
Assuntos
Animais , Ratos , Antineoplásicos/farmacologia , Extratos Vegetais/farmacologia , Heliotropium/química , Neoplasias da Glândula Tireoide/tratamento farmacológico , Proliferação de Células , Benzofuranos , Cicloexanos , Exsudatos de Plantas/farmacologia , Resinas Vegetais , Compostos de Espiro , Sobrevivência Celular , Técnicas de Cultura de TecidosRESUMO
Infectious pancreatic necrosis is a disease caused by a birnavirus affecting several wild and commercial aquatic organisms. This infectious disease results in significant losses in the farming industry and therefore effective therapeutic agents are needed to control outbreaks caused by this pathogen. Our goal was to evaluate in vitro antiviral effect of a group of natural compounds (geranyl aromatic derivatives) isolated from the resinous exudate of the plant Heliotropium filifolium (Heliotropiaceae), semi-synthetics compounds obtained from them, and the resinous exudate, on CHSE-214 cell line infected with infectious pancreatic necrosis virus (IPNV) using a virus plaque inhibition assay at various concentrations. The compound ester filifolinyl senecionate was the best antiviral with EC(50) 160 microg/mL and a cytotoxic concentration required to reduce cell viability by 50% up to 400 microg/mL. In order to obtain information about the mechanism of the antiviral action, was evaluated the influence of ester filifolinyl senecionate on the viral RNA synthesis. This compound produced inhibition of the synthesis of viral genomic RNA, suggesting that the ester could be interacting with the viral RNA during the viral cycle. Additionally, a preliminary study of the interaction between ester and a sample of single-stranded RNA was studied at the level of theory Restricted Hartree Fock PM3 method. The results showed that the ester formed hydrogen bonds mainly with nitrogenous bases but not with ribose and phosphate. These results allow propose that the ester filifolinyl senecionate is a good candidate for used as antiviral therapy for IPN virus in salmon fry.
Assuntos
Antivirais/farmacologia , Heliotropium/química , Vírus da Necrose Pancreática Infecciosa/efeitos dos fármacos , Vírus da Necrose Pancreática Infecciosa/fisiologia , Exsudatos de Plantas/farmacologia , Replicação Viral/efeitos dos fármacos , Animais , Antivirais/síntese química , Antivirais/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , DNA/metabolismo , Exsudatos de Plantas/química , RNA/metabolismo , SalmãoRESUMO
Heliotropium sclerocarpum Phil. (Heliotropiaceae) is a resinous bush that grows in the Atacama of northern Chile. The chemical composition of its resinous exudate was analyzed for the first time. One aromatic geranyl derivative: filifolinol (1), one flavanone: naringenin (2) and a new type of 3-oxo-2-arylbenzofuran derivative 3 were isolated and their structures were determined. The antioxidant activity of the phenolic compounds and resin was evaluated using the bleaching of DPPH radical method and expressed as fast reacting equivalents (FRE) and total reacting equivalents (TRE).
Assuntos
Antioxidantes/química , Heliotropium/química , Fenóis/química , Resinas Vegetais/química , Flavanonas/química , Espectroscopia de Ressonância Magnética , Estrutura MolecularRESUMO
H. taltalense (Phil.) Johnst. (Heliotropiaceae) is an endemic species of the northern coast of Chile that produces a resinous exudate that covers its foliar surface and stems. Its chemical composition was analyzed for the first time, and two aromatic geranyl derivatives: filifolinol and filifolinyl senecionate and three flavonoids - naringenin, 3-O-methylgalangin and 7-O-methyleriodictiol - were isolated. The antioxidant activity of the flavonoids and the resinous exudates was carried out by measuring the 1,1-diphenyl-2-picrylhydrazyl (DPPH) bleaching effect in ethanolic solution and in sodium dodecyl sulfate (SDS) micelles. The influence of the reaction medium was analyzed. The initial velocity reactions for the pure compounds and for the extract were higher in SDS media than in ethanolic solution. The velocity of reaction observed was interpreted in terms of the reaction medium environment in the micelle.
Assuntos
Antioxidantes/química , Flavonoides/química , Heliotropium/química , Resinas Vegetais/química , Compostos de Bifenilo/química , Flavanonas/química , Estrutura Molecular , Picratos/químicaRESUMO
A re-examination of cuticular components of Heliotropium filifolium allowed the isolation of four new compounds: 3'-hydroxy-2',2',6'-trimethyl-3H-spiro[1-benzo-furan-2,1'-cyclohexane]-5-carboxylic acid(2), methyl 3'-acetyloxy-2',2',6'-trimethyl-3H-spiro[1-benzofuran-2,1'-cyclohexane]-5-carboxylate (3), methyl 3'-isopentanoyloxy-2',2',6'-trimethyl-3H-spiro[1-benzofuran-2,1'-cyclohexane]-5-carboxylate (4) and methyl 3'-benzoyloxy-2',2',6'-trimethyl-3H-spiro[1-benzofuran-2,1'-cyclohexane]-5-carboxylate (5).Compounds 2-5 were identified by their spectroscopic analogies with filifolinol (1), and their structures confirmed by chemical correlation with 1. The antimicrobial properties of the compounds were tested against Gram positive and Gram negative bacteria. Some of them proved to be active against Gram positive, but inactive against Gram negative bacteria. In searching for structure-activity relationships from the obtained MIC values, lipophilicity was shown to be an important variable.
Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Heliotropium/química , Benzofuranos/química , Benzofuranos/farmacologia , Cicloexanos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Interações Hidrofóbicas e Hidrofílicas , Testes de Sensibilidade Microbiana , Estrutura Molecular , Extratos Vegetais , Compostos de Espiro , Relação Estrutura-AtividadeRESUMO
Heliotropium glutinosum Phil. (Heliotropiceae) is a resinous bush that grows at a height of 2000 m in Chañaral, Chile. From the resinous exudates of Heliotropium glutinosum Phil. a new aromatic geranyl derivative: 4-methoxy-3-[(2)-7'-methyl-3'-hydroxymethyl-2',6'-octadienyl] phenol (1) and three flavonoids: 5,3'-dihydroxy-7,4'-dimethoxyflavanone (2), 5,4'-dihydroxy-7-methoxyflavanone (3) and 4'-acetyl-5-hydroxy-7-methoxyflavanone (4) were isolated and their structures were determined. Their antioxidant activity were evaluated using the bleaching of ABTS and DPPH derived cation radical methods and expressed in terms of FRE (fast reacting equivalents) and TRE (total reacting equivalents), where FRE is a good measure of the quick protection of a given compound against oxidants and TRE measures the degree of long-term protection of the antioxidant, or how effective it is against a strong oxidative stress.
Assuntos
Antioxidantes/farmacologia , Heliotropium/química , Antioxidantes/química , Benzotiazóis , Compostos de Bifenilo/química , Radicais Livres , Hidrazinas/química , Espectroscopia de Ressonância Magnética , Picratos , Ácidos Sulfônicos/química , Tiazóis/químicaRESUMO
Relationships between the structural characteristics of flavonoids isolated from the resinous exudate of Heliotropium sinuatum and their antioxidant activity were studied. Radical formation energies, DeltaH of dehydrogenation and spin densities were calculated using DFT methods (B3LYP/6-31G*). Results show that studied flavonoids can be divided into two sets according to their activity. It has been found that antioxidant activity depends both on substitution pattern of hydroxyl groups of the flavonoid skeleton and the presence of an unsaturation at the C2-C3 bond. A good tendency between DeltaH of dehydrogenation and antioxidant activity was established.
Assuntos
Antioxidantes/farmacologia , Flavonoides/farmacologia , Heliotropium/química , Antioxidantes/química , Flavonoides/química , Flavonoides/isolamento & purificação , Hidrogenação , Radical Hidroxila/química , Extratos Vegetais/química , Relação Estrutura-AtividadeRESUMO
From the resinous exudate of Heliotropium sinuatum (family Boraginaceae), a new compound: 4-(3',5'-dihydroxynonadecyl)phenol 1, together with eight previously described flavonoids, were isolated and their antioxidant activities were assessed by quenching measurements with ABTS and DPPH cation radicals.