RESUMO
Lychnophora pinaster, known as arnica-mineira, is endemic to campos rupestres, at risk of extinction. The present study aimed to characterize the ecogeography and phenolic constituents of 11 L. pinaster populations collected in the mesoregions North, Jequitinhonha, Metropolitan of Belo Horizonte and Campos das Vertentes in the state of Minas Gerais, Brazil. Phenolic constituents were identified and quantified by Ultra-high performance liquid chromatography- mass spectrometry. Lychnophora pinaster occurs in sites at high altitude (700 and 1498 m), annual rainfall of up to 1455 m, soils with low fertility and predominantly loamy texture. Therefore, it can be considered tolerant to acidic soils, with low availability of nutrient. The most abundant substances in all populations were vitexin (18 - 1345 ng/g) and chlorogenic acid (60 - 767 ng/g). The 11 populations formed four groups in relation to the phenolic constituents, with group 1 consisting of the populations of the North Mesoregion (GM, OD) and Jetiquinhonha (DIMa), group 2, the Metropolitan of Belo Horizonte (SRM, NLSC, SM, RPS, CTRA), group 3, the North Mesoregion (ODMa and DI), and group 4, the Campos das Vertentes (CC). Among the populations, only those from the Metropolitan of Belo Horizonte showed correlation of soil properties with phenolic constituents.
Assuntos
Arnica , Asteraceae , Brasil/epidemiologia , Extratos Vegetais , SoloRESUMO
Eugenia pyriformis, typically known as uvaia, ubaia, uvaieira, uvalha or uvalha-do-campo, is a plant representative of the Myrtaceae family. E. pyriformis decreased HeLa cells proliferation, can induce cell death and reduce cell migration that may be related to metastasis and induction of cell death by apoptosis inâ vitro assays. Its leaves are used in folk medicine for hypertension control, decreased cholesterol and uric acid, slimming, astringent, and digestive. In this work, the evaluation of the inâ vitro anticancer potential Cervical Cancer (HeLa cells) and phytochemical analysis in E. pyriformes was performed. It was possible to quantify phenolic compounds and total flavonoids and identify Chlorogenic acid, Quercetrin, and Myricitrin in this species. The crude extract and ethyl acetate fraction inhibited cell viability by 50 % in the dose of 44.42â µg/mL and 40.39â µg/mL, respectively. The induced effector caspase 3/7 activation, which results in apoptosis and the ethyl acetate fraction, decreases cell migration of cancer cell lines; it is responsible for the cleavage of several cellular proteins that will result in the classic phenotype of the apoptotic cell.
Assuntos
Eugenia , Neoplasias do Colo do Útero , Antioxidantes/química , Eugenia/química , Feminino , Células HeLa , Humanos , Extratos Vegetais/química , Folhas de Planta/química , Neoplasias do Colo do Útero/tratamento farmacológicoRESUMO
Stingless bees are responsible for pollinating up to 90% of Brazilian flora, so their study is of commercial and ecological importance. Stingless bees mix plant resins with wax and soil, forming geopropolis. Studies of the variability in composition and activity due to species, place and season of collection are lacking. Yield, total phenolic and flavonoid content, and antioxidant activity (via DPPH) of the extracts of fifteen M. quadrifasciata (Mandaçaia) geopropolis samples collected over a year in the State of São Paulo, Brazil, as well as two samples from different regions of the state of Minas Gerais in Brazil were compared. Composition was determined by ultra-high-resolution liquid chromatography and mass spectrometry, identifying 16 compounds. The month and region of collection affected the available plant resins and influenced their yield, composition and antioxidant capacity. Depending on the place of collection, M. quadrifasciata geopropolis is a promising natural source of antioxidant phenolic compounds.
Assuntos
Antioxidantes , Própole , Animais , Antioxidantes/química , Abelhas , Brasil , Flavonoides/análise , Fenóis/análise , Própole/químicaRESUMO
Lychnophora pinaster Mart. (Asteraceae) is endemic to the Brazilian Cerrado. It is distributed along the altitudinal gradient of the mountainous ranges of the state of Minas Gerais. This study aimed to evaluate the influence of altitude on the genetic diversity of L. pinaster populations and the effects of altitude and climatic factors on essential oil chemical composition. Essential oils from L. pinaster populations from the north (North 01, North 02, and North 03, 700-859 m) and the Metropolitan region of Belo Horizonte (MhBH 01 and MrBH 02, 1366-1498 m) were analyzed. SNP markers from L. pinaster in these regions and Campos das Vertentes (CV 01, CV 02, and CV 03, 1055-1292 m) were also analyzed. The main compounds in essential oils were 14-hydroxy-α-humulene (North 01 and North 03), cedr-8(15)-en-9-α-ol (North 02), 14-acetoxy-α-humulene (MrBH 01), and 4-oxo-15-nor-eudesman-11-ene (MrBH 02). Hierarchical cluster and heatmap analyses showed that the North and MrBH populations included five different groups, indicating the chemical composition of essential oils is distinct in each population. Furthermore, principal component analysis showed that higher altitudes (1366 m and 1498 m) in the MrBH influence the chemical composition of essential oils, and climatic factors determine the chemical composition in North region. The genetic diversity showed that most alleles are in Hardy-Weinberg equilibrium and imply high genetic variation and genetic polymorphisms between populations. Furthermore, the results of Mantel tests (R = 0.3861517; p = 0.04709529; R = 0.9423121; p = 0.02739726) also showed that higher altitude (>1360 m) shapes the genetic diversity at the MrBH. The genetic structure showed that higher altitudes (>1360 m) contribute to the structure of the MrBH populations, but not to North and CV populations. Therefore, the altitudinal ranges of Minas Gerais mountainous ranges determine the higher genetic and chemical diversity of L. pinaster populations.
Assuntos
Altitude , Asteraceae , Óleos Voláteis , Óleos de Plantas/química , Asteraceae/química , Asteraceae/genética , Brasil , Genômica , Óleos Voláteis/química , Análise de Componente PrincipalRESUMO
ABSTRACT This study compared the influence of mechanical damage and drying on the chemical composition of Mikania glomerata Spreng. and Mikania laevigata Sch.Bip. ex Baker, Asteraceae, leaves. Leaves were collected 1-24 h after damage. Oven-drying at 40ºC and shade-drying at ambient temperature were compared to lyophilization. Samples were extracted in 70% ethanol and analyzed by ultra-high-performance liquid chromatography with mass spectrometry. Significant (p < 0.05) increases of caffeoylquinic acids were observed in damaged leaves of both species and coumarin decreased in M. laevigata, indicating stress. Although the final water content was similar, the drying method affected the leaf composition. In shade-dried leaves of M. laevigata coumarin decreased and the presence of umbelliferone was observed; caffeoylquinic acid contents increased for 288 h in in both species. Apparently, enzymes were inactivated after 6 h in oven drying, stabilizing their chemical composition, while shade drying allowed enzymatic and microbial activity to continue; illustrating the importance of post harvesting procedures on the quality of medicinal plants.
RESUMO
The objective was to investigate the effects of the maternal consumption of the green tea extract during pregnancy and lactation on mothers and offspring metabolism. The female Wistar rats, on the first day of pregnancy until the end of lactation, was divided into groups: MC- received water and ME- received green tea extract (400 mg/kg body weight/day), both ingested control diet. After lactation, at day 28th post-partum, the mothers and pups from each mother were euthanized and composed the groups: FC- pup from mother received water and FE- pup from mother received green tea extract. The ME group increased IL-10/TNF-α ratio and IL-1ß content in the mesenteric and IL-1ß content in retroperitoneal adipose tissues, and decreased catalase activity. The FE group decreased the retroperitoneal adipose tissue relative weight and SOD activity, but increased adiponectin, LPS, IL-10 and IL-6 content and IL-10/TNF-α ratio in retroperitoneal, IL-10 and TNF-α content in gonadal, and IL-6 content in mesenteric adipose tissues. In summary, the maternal consumption of green tea extract associated with control diet ingestion during pregnancy and lactation altered the inflammatory status of mothers and 28d-old offspring. These data elucidate the effects of green tea during pregnancy and lactation on maternal and offspring metabolism.
Assuntos
Antioxidantes/farmacologia , Mediadores da Inflamação/metabolismo , Inflamação/metabolismo , Lactação , Mães , Extratos Vegetais/farmacologia , Chá/química , Animais , Peso Corporal , Feminino , Inflamação/tratamento farmacológico , Inflamação/patologia , Gravidez , Ratos , Ratos WistarRESUMO
Under field conditions, plants are exposed to cycles of dehydration and rehydration during their lifespan. In this study, we hypothesized that sugarcane plants previously exposed to cycles of water deficits will perform better than plants that have never faced water deficits when both are subjected to low water availability. Sugarcane plants were grown in a nutrient solution and exposed to one (1WD), two (2WD) or three (3WD) water deficit cycles. As the reference, plants were grown in a nutrient solution without adding polyethylene glycol. Under water deficits, leaf gas exchange was significantly reduced in 1WD and 2WD plants. However, 3WD plants showed similar CO2 assimilation and lower stomatal conductance compared to the reference plants, with increases in intrinsic water-use efficiency. Abscisic acid concentrations were lower in 3WD plants than in 1WD plants. Our data revealed root H2O2 concentration as an important chemical signal, with the highest root H2O2 concentrations found in 3WD plants. These plants presented higher root dry matter and root:shoot ratios compared to the reference plants, as well as higher biomass production when water was available. Our data suggest that sugarcane plants were able to store information from previous stressful events, with plant performance improving under water deficits. In addition, our findings provide a new perspective for increasing drought tolerance in sugarcane plants under nursery conditions.
Assuntos
Secas , Saccharum/fisiologia , Água/metabolismo , Ácido Abscísico/metabolismo , Peróxido de Hidrogênio/metabolismo , Folhas de Planta/anatomia & histologia , Folhas de Planta/química , Folhas de Planta/fisiologia , Raízes de Plantas/fisiologia , Saccharum/anatomia & histologia , Saccharum/química , Transdução de Sinais/fisiologiaRESUMO
The high temperatures used to fry fish may induce thermo-oxidation of cholesterol, forming cholesterol oxidation products (COPs). COPs have been associated to coronary heart diseases, atherosclerosis, and other chronic diseases. Air fryers are an alternative thermal process technology to fry foods without oil, and are considered a healthier cooking method. This study is the 1st to evaluate the formation of COPs and the degradation of polyunsaturated fatty acids (PUFAs) in air-fried sardine fillets. Furthermore, we evaluated the effect of fresh herbs added as natural antioxidants to sardines subjected to air frying. Parsley (Petroselinum crispum), chives (Allium schoenoprasum L.), and a mixture of both herbs (cheiro-verde) were added in quantities of 0%, 2%, and 4%. Air frying significantly decreased the content of essential PUFAs, and increased the levels of COPs from 61.2 (raw) to 283 µg/g (P < 0.05) in the control samples. However, the use of herbs as natural antioxidants proved to be effective reducing such levels of COPs in most samples. The addition of 4% of cheiro-verde in air-fried sardines presented the best protective effect against lipid oxidation. PRACTICAL APPLICATION: Fish is an important source of essential lipids. However, oxidized cholesterol products, which are formed during thermal processing, are potential hazards to human health. Air fryers present an alternative thermal process for frying food without oil, and this method of cooking is considered to be more convenient and healthier This study shows that the air frying increased the formation of cholesterol oxidation products and decreased the essential polyunsaturated fatty acids in sardine fillets. However, the lipid oxidation is significantly reduced by adding fresh herbs, such as parsley (Petroselinum crispum), chives (Allium schoenoprasum L.), or a mixture of both herbs (cheiro-verde) that are natural antioxidants.
Assuntos
Colesterol/química , Culinária/métodos , Ácidos Graxos/química , Produtos Pesqueiros/análise , Aditivos Alimentares/análise , Petroselinum/química , Allium/química , Animais , Antioxidantes/química , Culinária/instrumentação , Peixes , Temperatura Alta , Humanos , Lipídeos/química , OxirreduçãoRESUMO
Geopropolis is a special type of propolis produced by stingless bees. Several pharmacological properties have been described for different types of geopropolis, but there have been no previous studies of the geopropolis from Melipona mondury. In this study, we investigated the antioxidant, antibacterial, and antiproliferative activities of M. mondury geopropolis, and determined its chemical profile. The antioxidant activity was determined using in vitro ABTS·+, ·DPPH, and ß-carotene/linoleic acid co-oxidation methods. The antibacterial activity was determined using a microdilution method with Pseudomonas aeruginosa, Staphylococcus aureus, and methicillin-resistant S. aureus. The antiproliferative effect was determined in tumor cell lines using the Alamar Blue assay. The chemical profile was obtained using UHPLC-MS and UHPLC-MS/MS. The butanolic fraction had the highest concentration of phenolic compounds and more potent antioxidant properties in all assays. This fraction also had bacteriostatic and bactericidal effects against all bacterial strains at low concentrations, especially S. aureus. The hexane fraction had the highest antiproliferative potential, with IC50 values ranging from 24.2 to 46.6 µg/mL in HL-60 (human promyelocytic leukemia cell) and K562 (human chronic myelocytic leukemia cell), respectively. Preliminary chemical analysis indicates the presence of terpenes and gallic acid in the geopropolis. Our results indicate the therapeutic potential of geopropolis from M. mondury against inflammatory, oxidative, infectious, and neoplastic diseases.
Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Abelhas/química , Fenóis/farmacologia , Própole/química , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Animais , Staphylococcus aureus Resistente à Meticilina , Espectrometria de Massas em TandemRESUMO
ABSTRACT Geopropolis is a special type of propolis produced by stingless bees. Several pharmacological properties have been described for different types of geopropolis, but there have been no previous studies of the geopropolis from Melipona mondury. In this study, we investigated the antioxidant, antibacterial, and antiproliferative activities of M. mondury geopropolis, and determined its chemical profile. The antioxidant activity was determined using in vitro ABTS·+, ·DPPH, and β-carotene/linoleic acid co-oxidation methods. The antibacterial activity was determined using a microdilution method with Pseudomonas aeruginosa, Staphylococcus aureus, and methicillin-resistant S. aureus. The antiproliferative effect was determined in tumor cell lines using the Alamar Blue assay. The chemical profile was obtained using UHPLC-MS and UHPLC-MS/MS. The butanolic fraction had the highest concentration of phenolic compounds and more potent antioxidant properties in all assays. This fraction also had bacteriostatic and bactericidal effects against all bacterial strains at low concentrations, especially S. aureus. The hexane fraction had the highest antiproliferative potential, with IC50 values ranging from 24.2 to 46.6 µg/mL in HL-60 (human promyelocytic leukemia cell) and K562 (human chronic myelocytic leukemia cell), respectively. Preliminary chemical analysis indicates the presence of terpenes and gallic acid in the geopropolis. Our results indicate the therapeutic potential of geopropolis from M. mondury against inflammatory, oxidative, infectious, and neoplastic diseases.
Assuntos
Animais , Fenóis/farmacologia , Própole/química , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Abelhas/química , Espectrometria de Massas em Tandem , Staphylococcus aureus Resistente à MeticilinaRESUMO
Atrazine is still one of the most used agricultural pesticides worldwide and it has been recognized as a major contaminant of surface and ground water. The aims of this research were to isolate an endophytic microorganism from leaves of sugarcane, evaluate its ability to degrade atrazine, and investigate the formation of metabolites. By sequencing of the 16S rRNA gene, the endophytic isolate atz2 was identified as Streptomyces sp. The reduction in atrazine concentration by Streptomyces sp. atz2 was 98 % and UHPLC-MS/MS analyses showed the appearance of an unknown metabolite observed as m/z 311. Ecotoxicity tests with an aquatic organism, Daphnia similis, confirmed that this metabolite was nontoxic. This mechanism of detoxification of atrazine is different from the ones of other free-living microorganisms that inhabit the soil or rhizosphere. The results show new aspects of atrazine detoxification, highlighting a new role of endophytic bacteria in plants.
Assuntos
Atrazina/metabolismo , Streptomyces/metabolismo , Agricultura , Animais , Biodegradação Ambiental , Daphnia/efeitos dos fármacos , RNA Ribossômico 16S/química , RNA Ribossômico 16S/genética , Saccharum/metabolismo , Saccharum/microbiologia , Solo/química , Microbiologia do Solo , Streptomyces/isolamento & purificação , Espectrometria de Massas em TandemRESUMO
Abstract In Brazil, Mikania glomerata Spreng. and M. laevigata Sch. Bip. ex Baker, Asteraceae, known popularly as guaco, are widely used for colds and asthma. Although coumarin is adopted as the chemical marker of both species, it was not always detected in M. glomerata, for which chlorogenic acid was identified and quantified instead. The purpose of this study was to develop and validate a method to quantify both coumarin and chlorogenic acid and apply it to extracts of plants identified as M. glomerata, M. laevigata, or as guaco, to determine the pattern of composition of these two species and to observe differences between oven-dried and lyophilized leaves. A method using ultra-high resolution liquid chromatography–mass spectrometry (UHPLC–MS) in the full scan mode was validated for selectivity, matrix effect, linearity, limits of detection and quantification, precision and accuracy. The concentration of coumarin varied between species and samples, therefore these two species should not be used interchangeably. The concentration of chlorogenic acid was also determined for all samples. The UHPLC–MS method permitted the quantification of coumarin and chlorogenic acid in 16 samples of guaco and several commercial samples were possibly misidentified.
RESUMO
Propolis is a resin that bees collect from different plant sources and use in the defense of the bee community. The intricate composition of propolis varies depending on plant sources from different geographic regions and many types have been reported. Red coloured propolis found in several states in Brazil and in other countries has known antimicrobial and antioxidant activity. Different analytical methods have been applied to studies regarding the chemical composition and plant origins of red propolis. In this study samples of red propolis from different regions have been characterised using direct infusion electrospray ionisation mass spectrometry (ESI(-)-MS) fingerprinting. Data from the fingerprints was extracted and analysed by multivariate analysis to group the samples according to their composition and marker compounds. Despite similar colour, the red coloured propolis samples were divided into three groups due to contrasting chemical composition, confirming the need to properly characterise the chemical composition of propolis.
Assuntos
Própole/química , Animais , Biomarcadores/análise , Brasil , Cor , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
This study was undertaken to evaluate the effect of Alternathera brasiliana (Amaranthaceae) extracts as photosensitizing agents in photodynamic antimicrobial therapies (PACT) against Staphylococcus aureus, Staphylococcus epidermidis and Candida dubliniensis. The crude hexane and ethanol extracts were obtained from A. brasiliana whole plant and showed absortion from 650 to 700 nm. Also, singlet molecular oxygen (1O2) production (type II photosensitization reaction) was examined, and the results show that 1,3-diphenylisobenzofuran photodegradation was greatly enhanced in the presence of the A. brasiliana extracts. One plate in each assay was irradiated while the other was not irradiated, the number of colony-forming units per milliliter (CFU/mL) was obtained, and data analyzed by the Tukey test. The chemical composition of the extracts was determined by chromatographic and spectrometric techniques; steroids, triterpenes, and flavonoids were identified. Laser irradiation alone at 685 nm using diode laser, output power of 35 mW, and energy of 28 J/cm2, or non-irradiated crude extracts in sub-inhibitory concentration did not reduce the number of CFU/mL significantly, whereas irradiated hexane and ethanol extracts, in sub-inhibitory concentrations, inhibited the growth of these microorganisms. The photoactivation of hexane and ethanol extracts of A. brasiliana, in sub-inhibitory concentrations, using red laser radiation at 685 nm had an antimicrobial effect.
Assuntos
Amaranthaceae/química , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Bactérias/efeitos dos fármacos , Fungos/efeitos dos fármacos , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Extratos Vegetais/farmacologia , Antibacterianos/química , Antifúngicos/química , Candida/efeitos dos fármacos , Etanol , Flavonoides/análise , Hexanos , Fármacos Fotossensibilizantes/química , Extratos Vegetais/química , Oxigênio Singlete/metabolismo , Staphylococcus/efeitos dos fármacos , Esteroides/análise , Triterpenos/análiseRESUMO
Lignin is a polymer found in the cell wall of plants and is one of the main obstacles to the implementation of second-generation ethanol production because it confers the recalcitrance of the lignocellulosic material. The recalcitrance of biomass is affected by the amount of lignin, by its monomer composition, and the way the monomers are arranged in the plant cell wall. Analysis of lignin structure demands mass spectrometry analysis, and identification of oligomers is usually based on libraries produced by laborious protocols. A robust method to build a do-it-yourself lignin oligomer library was tested. This library can be built using commercially available enzymes, standards, and reagents and is relatively easy to accomplish. An ultrahigh performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the separation and characterization of monomers and oligomers was developed and was equally applicable to the synthetic lignin and to soluble lignin extracted from a sample of sugar cane.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Bases de Dados Factuais , Lignina/análise , Lignina/química , Saccharum/química , Espectrometria de Massas em Tandem/métodos , Dimerização , SolubilidadeRESUMO
Chemical profiles of a representative set of 49 propolis ethanolic extracts collected worldwide (North and South America, Europe, Asia and Oceania) were obtained via easy ambient sonic-spray ionization mass spectrometry (EASI-MS). This simple and easily implemented fingerprinting technique analyses directly (without any pre-separation or sample manipulation) a tiny droplet of the ethanolic extract placed on a inert surface under ambient conditions. Data acquisition took about a minute per sample with no substantial sample carry-over. Extraction of propolis with ethanol by using an ultrasonic bath method gave EASI-MS data similar to the traditional maceration method, reducing total analysis time for the crude propolis resin from a week to just ca 1h. Principal component analysis of the EASI-MS data is shown to group samples according to the plant sources of their resins, which characterizes their geographical origin.
Assuntos
Espectrometria de Massas/métodos , Própole/análise , Ultrassom , Análise de Componente Principal , Própole/química , Reprodutibilidade dos Testes , Fatores de TempoRESUMO
Pilocarpine, an important imidazole alkaloid, is extracted from the leaves of Pilocarpus microphyllus (Rutaceae), known in Brazil as jaborandi and used mainly for the treatment of glaucoma. Jaborandi leaves also contain other imidazole alkaloids, whose pharmacological and physiological properties are unknown, and whose biosynthetic pathways are under investigation. In the present study, a HPLC method coupled with ESI-MS(n) was developed for their qualitative and quantitative analysis. This method permits the chromatographic separation of the imidazole alkaloids found in extracts of jaborandi, as well as the MS/MS analysis of the individual compounds. Thus two samples: leaves of P. microphyllus and a paste that is left over after the industrial extraction of pilocarpine; were compared. The paste was found to contain significant amounts of pilocarpine and other imidazole alkaloids, but had a slightly different alkaloid profile than the leaf extract. The method is suitable for the routine analysis of samples containing these alkaloids, as well as for the separation and identification of known and novel alkaloids from this family, and may be applied to further studies of the biosynthetic pathway of pilocarpine in P. microphyllus.
Assuntos
Alcaloides/química , Imidazóis/química , Pilocarpus/química , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Alcaloides/análise , Cromatografia Líquida de Alta Pressão , Imidazóis/análise , Pilocarpina/química , Extratos Vegetais/análise , Extratos Vegetais/químicaRESUMO
The antioxidant activity of flavonoids is believed to increase when they are coordinated with transition metal ions. However, the literature on this subject is contradictory and the outcome seems to largely depend on the experimental conditions. In order to understand the contribution of the metal coordination and the type of interaction between a flavonoid and the metal ion, in this study a new metal complex of Cu (II) with naringin was synthesized and characterized by FT-IR, UV-VIS, mass spectrometry (ESI-MS/MS), elemental analysis and 1H-NMR. The results of these analyses indicate that the complex has a Cu (II) ion coordinated via positions 4 and 5 of the flavonoid. The antioxidant, anti-inflammatory and antimicrobial activities of this complex were studied and compared with the activity of free naringin. The Naringin-Cu (II) complex 1 showed higher antioxidant, anti-inflammatory and tumor cell cytotoxicity activities than free naringin without reducing cell viability.
Assuntos
Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Cobre/química , Flavanonas/síntese química , Flavanonas/farmacologia , Animais , Compostos de Bifenilo/química , Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Flavanonas/administração & dosagem , Flavanonas/química , Sequestradores de Radicais Livres/química , Humanos , Hidrazinas/química , Concentração de Íons de Hidrogênio , Células K562 , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Testes de Sensibilidade Microbiana , Picratos , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria UltravioletaRESUMO
Aqueous extracts of green yerba maté (Ilex paraguariensis) and green tea (Camellia sinensis) are good sources of phenolic antioxidants, as already described in the literature. The subject of this study were organic extracts from yerba maté, both green and roasted, and from green tea. Their phenolic profiles were characterized by direct infusion electrospray insertion mass spectrometry (ESI-MS) and their free radical scavenging activity was determined by the DPPH assay. Organic extracts containing phenolic antioxidants might be used as natural antioxidants by the food industry, replacing the synthetic phenolic additives used nowadays. Ethanolic and aqueous extracts from green yerba maté, roasted yerba maté and green tea showed excellent DPPH scavenging activity (>89%). The ether extracts from green and roasted yerba maté displayed a weak scavenging activity, different from the behavior observed for the green tea ether extract. The main phenolic compounds identified in green yerba maté water and ethanolic extracts were: caffeic acid, quinic acid, caffeoyl glucose, caffeoylquinic acid, feruloylquinic acid, dicaffeoylquinic acid and rutin. After the roasting process two new compounds were formed: caffeoylshikimic acid and dicaffeoylshikimic acid. The ethanolic extracts from yerba maté, both roasted and green, with lower content of phenolic compounds (3.80 and 2.83 mg/mL) presented high antioxidant activity and even at very low phenolic concentrations, ether extract from GT (0.07 mg/mL) inhibited DPPH over 90%.
Assuntos
Antioxidantes/isolamento & purificação , Camellia sinensis/química , Ilex paraguariensis/química , Fenóis/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray , Sequestradores de Radicais Livres/metabolismo , Extratos Vegetais/químicaRESUMO
In this work the interaction of DNA and the flavonoid-transition metal complex (Cu(II)-naringin complex) is characterized. The interaction was evaluated by using electrochemical ssDNA- and dsDNA-based biosensors and the results were supported by UV, CD and (1)H NMR data. In the electrochemical method, changes in the oxidation peak of the guanine and adenine bases obtained by square wave voltammetry (SWV) showed evidence of the interaction. The variations of the spectroscopic characteristics of DNA and Cu(II)-naringin complex in aqueous medium demonstrated that the predominant interaction mode may be by intercalation. Cu(II)-naringin complex interacts to dsDNA probably via N(7) of guanine site.