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1.
Food Funct ; 11(7): 6652-6665, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32657286

RESUMO

Dietary fiber is a carrier of abundant polyphenols and the potential benefits have attracted increasing attention. In this study, we performed in vitro simulated digestion in the oral, gastric and intestinal phases, and colonic fermentation with human fecal microbes, to explore the release and metabolism of bound polyphenols from carrot dietary fiber (CDF) and the potential activity. The results indicate that the bound polyphenols released by the fecal fermentation process (30.43%) from CDF were higher than in the digestion process (0.89%); 26 polyphenols and their catabolites were detected and the microbial pathways of primary polyphenols were proposed. The significant disintegration of the sheet-like structure of CDF after the in vitro fermentation was comparable to that of the digestion treatment. The released polyphenols exhibited antioxidant capacity and α-glucosidase inhibitory activity. The microbe community structure was regulated by the fecal-fermented CDF through decreasing the Firmicutes to Bacteroidetes ratio, improving the relative abundance (RA) of the beneficial microbiota and suppressing the RA of various harmful microbiota. Overall, this study suggests that the bound polyphenols might exert potential benefits in the gastrointestinal and colonic health of the CDF.


Assuntos
Colo/microbiologia , Daucus carota/química , Fibras na Dieta/metabolismo , Digestão , Fermentação , Polifenóis/metabolismo , Ácidos Carbocíclicos/análise , Antioxidantes , Bactérias/classificação , Fezes/microbiologia , Flavonoides/análise , Microbioma Gastrointestinal/fisiologia , Inibidores de Glicosídeo Hidrolases/farmacologia , Polifenóis/análise , Polifenóis/farmacologia , alfa-Amilases/antagonistas & inibidores , alfa-Glucosidases
2.
Food Res Int ; 125: 108647, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31554035

RESUMO

Moringa oleifera leaves are used in Brazilian folk medicine for their hypoglycemic and nutritional properties. In this context, the chemical and biological characteristics were determined. Conventional successive solid-liquid extraction with simultaneous bioguided purification using solvents with different polarities was performed with M. oleifera leaves, yielding six fractions and extracts. The fractions showed better results for antioxidant activity than the extracts. All of them were evaluated by scavenging of synthetic free radicals and reactive oxygen species, and Fr-Ace and Fr-EtOAc showed >100 mg GAE g-1 of phenolic content, while for FRAP and ORAC assays the values were higher than 1600 µmol Fe2+ g-1 and 3500 mmol TEAC g-1 respectively. The UPLC-ESI-QTOF-MS analysis of hydroalcoholic extract (HE) allowed identifying 24 compounds, with flavonoid derivatives being the most abundant group. Furthermore, the alkaloid trigonelline and sesquiterpenoid abscisic acid were identified for the first time in M. oleifera leaves. Finally, gallic acid, caffeic acid, rutin and quercetin were found in concentrations of 16.5, 2129, 477.4 and 127.5 µg g-1 respectively in HE, all of which were higher in fractions and extracts. These results suggest that bioguided extraction is an important technique, due to its ability to concentrate active compounds in a logical and rational way. In addition, M. oleifera leaves grown in Brazil are an important source of phenolic compounds with antioxidant activity that can be used in food, nutraceutical and pharmaceutical products.


Assuntos
Moringa oleifera/química , Fenóis/isolamento & purificação , Extratos Vegetais/química , Folhas de Planta/química , Ácidos Carbocíclicos/análise , Alcaloides/análise , Aminoácidos/análise , Antioxidantes/análise , Brasil , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos
3.
J Ethnopharmacol ; 239: 111907, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31029759

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Chamomilla recutita (Asteraceae) is used worldwide as a soothing, anti-inflammatory and aromatherapy. In Brazil, it is one of the most cultivated medicinal species. However, the cultivation form may alter the production of compounds in the secondary metabolism and compromise the therapeutic purpose of this species. AIM OF THE STUDY: Evaluation of antiproliferative and genotoxic effects of infusions and essential oil of chamomile, cultivated with homeopathy, on the cell cycle of Allium cepa, as well as the determination of the phenolic compounds present in the infusions of the chamomile inflorescences. MATERIAL AND METHODS: For the Allium cepa test, two concentrations of 10 and 40 g L-1 of inflorescences of chamomile were used for the preparation of the infusions and essential oil diluted to 0.10%, referring to the six treatments obtained in field cultivation, in which were carried out the applications of homeopathy from the emergence to the harvest of the plants. Distilled water and ethanol were used as negative control and glyphosate 2% as a positive control. The determination of phenolic compounds present in the infusions was carried by liquid chromatography in a UHPLC apparatus. RESULTS: Chamomile infusions at concentrations of 10 and 40 g L-1 of inflorescence reduced mitotic index and emphasized antiproliferative activity on the cell cycle of Allium cepa. However, the treatments related to essential oil diluted to 0.10% showed a response variation dependent on the dynamization used, as well as for apigenin concentration. CONCLUSIONS: Therefore, cultivation with homeopathy does not induce a genotoxic effect in the use of infusions and essential oil of chamomile and it emphasize antiproliferative activity on the cell cycle of Allium cepa, favoring the sustainable cultivation and the safe use of this medicinal species when cultivated with homeopathy.


Assuntos
Camomila , Óleos Voláteis/farmacologia , Cebolas/efeitos dos fármacos , Extratos Vegetais/farmacologia , Ácidos Carbocíclicos/análise , Ácidos Carbocíclicos/farmacologia , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Flavonoides/análise , Flavonoides/farmacologia , Flores , Homeopatia , Óleos Voláteis/química , Cebolas/crescimento & desenvolvimento , Extratos Vegetais/química , Polifenóis/análise , Polifenóis/farmacologia
4.
Biomed Chromatogr ; 33(7): e4531, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30849182

RESUMO

Tanreqing capsule (TRQC) is a formulation frequently used in traditional Chinese medicine to treat pyrexia, cough, expectoration and pharyngalgia. Since the pharmacological action of traditional Chinese medicines is closely related to their complex and diverse constituents, understanding the exact composition of TRQC is important to elucidate its clinical effectiveness and mechanism of action as well as to establish quality control methods and resolve safety issues. Herein, we employed high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry for the simultaneous quantitation of 23 bioactive compounds in five batches of TRQC; the analytes could be categorized into five types: organic acids (seven compounds), flavonoids (10 compounds), iridoids (two compounds), phenylethanoid glycosides (two compounds) and bile acids (two compounds). The calibration curves for all analytes showed good linearity (r > 0.9953), and the inter- and intra-day precisions did not exceed 4.94 and 4.97%, respectively. The recoveries varied from 90.47% to 109.80%; the corresponding relative standard deviations (RSDs) did not exceed 4.94%; and the repeatability (RSD < 4.72%) and stability (RSD < 4.88%) were also within acceptable limits. Thus, this study can be viewed as a fundamental reference for setting comprehensive TRQC quality standards.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/química , Espectrometria de Massas em Tandem/métodos , Ácidos Carbocíclicos/análise , Flavonoides/análise , Glicosídeos/análise , Iridoides/análise , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
5.
Electrophoresis ; 39(23): 3006-3012, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30080273

RESUMO

A novel anion-exchange organic polymer monolithic column based on monomers N-benzylquininium chloride and acrylamide were firstly prepared by in situ copolymerization for capillary electrochromatography. Moreover, N-benzylquininium was firstly introduced as a strong anion-exchange functional group. A relatively strong anodic EOF was obtained in the pH values from 4.0 to 9.0, which was in the same direction with the electrophoretic mobility of acid compounds. Hence, the anion-exchange monolithic column was very suitable for the rapid separation of acid compounds. Eight acid compounds (2-chlorobenzoic acid, mandelic acid, 4-hydroxybenzoic acid, indole-3-acetic acid, 2-aminoterephthalic acid, 3,5-pyridinedicarboxylic acid, benzoic acid, and 4-aminobenzoic acid) were successfully separated on the monolithic column. The highest column efficiency was 4.60 × 105 plates/m (theoretical plates, N) for 3,5-pyridinedicarboxylic acid. The proposed monolithic column was characterized by SEM and FT-IR. The RSDs of the acid compounds migration time for run-to-run, day-to-day, and column-to-column were all less than 5.0%.


Assuntos
Ânions/química , Eletrocromatografia Capilar/métodos , Quinina/análogos & derivados , Ácidos Carbocíclicos/análise , Ácidos Carbocíclicos/química , Ácidos Carbocíclicos/isolamento & purificação , Eletrocromatografia Capilar/instrumentação , Eletro-Osmose , Concentração de Íons de Hidrogênio , Quinina/química , Reprodutibilidade dos Testes
6.
J Agric Food Chem ; 66(17): 4309-4318, 2018 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-29641196

RESUMO

Among the agronomic practices carried out in corn cultivation, the early sowing time is increasingly used by farmers of temperate regions to improve yield and reduce mycotoxin contamination of corn grains. The present study determined the influence of sowing time on the phytochemical content of grains of 10 colored genotypes of corn. There was a significant improvement of both grain yield (+26%), thousand kernel weight (+3%), and test weight (+2%) in plots sown early. The early sowing also significantly influenced the chemical composition of corn grains, with an increase in the concentration of cell-wall-bound phenolic acids (+5%) and ß-cryptoxanthin (+23%) and a decrease in the concentration of lutein (-18%) and total anthocyanins (-21%). Environmental conditions that occurred during grain development significantly influenced the phytochemical content of corn grain, and early spring sowing could impart advantages in terms of both productivity and content of some antioxidants of whole-meal corn flour.


Assuntos
Agricultura/métodos , Compostos Fitoquímicos/análise , Zea mays/química , Ácidos Carbocíclicos/análise , Antocianinas/análise , Antioxidantes/análise , beta-Criptoxantina/análise , Carotenoides/análise , Grão Comestível/química , Grão Comestível/crescimento & desenvolvimento , Meio Ambiente , Genótipo , Luteína/análise , Pigmentos Biológicos , Sementes/química , Sementes/crescimento & desenvolvimento , Fatores de Tempo , Zea mays/genética
7.
J Ethnopharmacol ; 218: 76-89, 2018 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-29432856

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Uncaria tomentosa (Willd. Ex Schult) DC is used by indigenous tribes in the Amazonian region of Central and South America to treat inflammation, allergies and asthma. The therapeutic properties of U. tomentosa have been attributed to the presence of tetracyclic and pentacyclic oxindole alkaloids and to phenolic acids. AIMS OF THE STUDY: To characterize aqueous bark extracts (ABE) and aqueous leaf extracts (ALE) of U. tomentosa and to compare their anti-inflammatory effects. MATERIALS AND METHODS: Constituents of the extracts were identified by ultra performance liquid chromatography-mass spectrometry. Anti-inflammatory activities were assessed in vitro by exposing lipopolysaccharide-stimulated macrophage cells (RAW264.7-Luc) to ABE, ALE and standard mitraphylline. In vivo assays were performed using a murine model of ovalbumin (OVA)-induced asthma. OVA-sensitized animals were treated with ABE or ALE while controls received dexamethasone or saline solution. Bronchial hyperresponsiveness, production of Th1 and Th2 cytokines, total and differential counts of inflammatory cells in the bronchoalveolar lavage (BAL) and lung tissue were determined. RESULTS: Mitraphylline, isomitraphylline, chlorogenic acid and quinic acid were detected in both extracts, while isorhyncophylline and rutin were detected only in ALE. ABE, ALE and mitraphylline inhibited the transcription of nuclear factor kappa-B in cell cultures, ALE and mitraphylline reduced the production of interleukin (IL)-6, and mitraphylline reduced production of tumor necrosis factor-alpha. Treatment with ABE and ALE at 50 and 200 mg kg-1, respectively, reduced respiratory elastance and tissue damping and elastance. ABE and ALE reduced the number of eosinophils in BAL, while ALE at 200 mg kg-1 reduced the levels of IL-4 and IL-5 in the lung homogenate. Peribronchial inflammation was significantly reduced by treatment with ABE and ALE at 50 and 100 mg kg-1 respectively. CONCLUSION: The results clarify for the first time the anti-inflammatory activity of U. tomentosa in a murine model of asthma. Although ABE and ALE exhibited distinct chemical compositions, both extracts inhibited the production of pro-inflammatory cytokines in vitro. In vivo assays revealed that ABE was more effective in treating asthmatic inflammation while ALE was more successful in controlling respiratory mechanics. Both extracts may have promising applications in the phytotherapy of allergic asthma.


Assuntos
Antiasmáticos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Asma/tratamento farmacológico , Hiper-Reatividade Brônquica/tratamento farmacológico , Unha-de-Gato , Extratos Vegetais/uso terapêutico , Ácidos Carbocíclicos/análise , Ácidos Carbocíclicos/farmacologia , Ácidos Carbocíclicos/uso terapêutico , Alérgenos/imunologia , Animais , Antiasmáticos/análise , Antiasmáticos/farmacologia , Anti-Inflamatórios/análise , Anti-Inflamatórios/farmacologia , Asma/imunologia , Hiper-Reatividade Brônquica/imunologia , Líquido da Lavagem Broncoalveolar , Sobrevivência Celular/efeitos dos fármacos , Citocinas/imunologia , Modelos Animais de Doenças , Alcaloides Indólicos/análise , Alcaloides Indólicos/farmacologia , Alcaloides Indólicos/uso terapêutico , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Camundongos , Ovalbumina/imunologia , Fitoterapia , Casca de Planta , Extratos Vegetais/análise , Extratos Vegetais/farmacologia , Folhas de Planta , Células RAW 264.7
8.
J Chromatogr Sci ; 56(2): 122-130, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29140413

RESUMO

Scrophulariae Radix is one of the most popular traditional Chinese medicines (TCMs). Primary processing of Scrophulariae Radix is an important link which closely related to the quality of products in this TCM. The aim of this study is to explore the influence of different processing methods on chemical constituents in Scrophulariae Radix. The difference of chemical constituents in Scrophulariae Radix processed by different methods was analyzed by using ultra fast liquid chromatography-triple quadrupole-time of flight mass spectrometry coupled with principal component analysis and orthogonal partial least squares discriminant analysis. Furthermore, the contents of 12 index differential constituents in Scrophulariae Radix processed by different methods were simultaneously determined by using ultra fast liquid chromatography coupled with triple quadrupole-linear ion trap mass spectrometry. Gray relational analysis was performed to evaluate the different processed samples according to the contents of 12 constituents. All of the results demonstrated that the quality of Scrophulariae Radix processed by "sweating" method was better. This study will provide the basic information for revealing the change law of chemical constituents in Scrophulariae Radix processed by different methods and facilitating selection of the suitable processing method of this TCM.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/análise , Medicamentos de Ervas Chinesas/química , Scrophularia , Espectrometria de Massas em Tandem/métodos , Ácidos Carbocíclicos/análise , Glucosídeos/análise , Limite de Detecção , Modelos Lineares , Fenóis/análise , Análise de Componente Principal , Reprodutibilidade dos Testes
9.
Chemosphere ; 168: 1042-1050, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27814951

RESUMO

A method was optimized for derivatization, separation, detection and quantification of salicylic acid, acetylsalicylic acid, nalidixic acid, ibuprofen, phenacetin, naproxen, ketoprofen, meclofenamic acid and diclofenac in surface water using gas chromatography-mass spectrometry. For most of the acidic drugs, recovery was in the range 60-110% and the percent standard deviation was below 15% for the entire method, with limits of detection ranging from 0.041 to 1.614 µg L-1. The developed method was applied in the analysis of acidic drugs in Umgeni River system, KwaZulu-Natal South Africa. All of the selected acidic drugs were detected and quantified, their concentration in Umgeni River system ranged from 0.0200 to 68.14 µg L-1.


Assuntos
Poluentes Químicos da Água/análise , Ácidos Carbocíclicos/análise , Aspirina/análise , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas/métodos , Concentração de Íons de Hidrogênio , Ácido Nalidíxico/análise , Naproxeno/análise , Fenacetina/análise , Rios/química , África do Sul , Água/química
10.
J Agric Food Chem ; 64(9): 1889-98, 2016 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-26890088

RESUMO

Plants have evolved various defense mechanisms against biotic stress. The most common mechanism involves the production of metabolites that act as defense compounds. Bacterial angular leaf spot disease (Xanthomonas fragariae) of the strawberry (Fragaria x ananassa) has become increasingly destructive to strawberry leaves and plant production. In this study, we examined metabolic changes associated with the establishment of long-term bacterial disease stress using UPLC-QTOF mass spectrometry. Infected leaves showed decreased levels of gallic acid derivatives and ellagitannins, which are related to the plant defense system. The levels of phenylalanine, tryptophan, and salicylic acid as precursors of aromatic secondary metabolites were increased in inoculated leaves, whereas levels of coumaric acid, quinic acid, and flavonoids were decreased in infected plants, which are involved in the phenylpropanoid pathway. In addition, phenylalanine ammonia-lyase (PAL) activity, a key enzyme in the phenylpropanoid pathway, was decreased following infection. These results suggest that long-term bacterial disease stress may lead to down-regulation of select molecules of the phenylpropanoid metabolic pathway in strawberry leaves. This approach could be applied to explore the metabolic pathway associated with plant protection/breeding in strawberry leaves.


Assuntos
Fragaria/metabolismo , Fragaria/microbiologia , Doenças das Plantas/microbiologia , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia , Xanthomonas , Ácidos Carbocíclicos/análise , Resistência à Doença , Flavonoides/análise , Ácido Gálico/análise , Taninos Hidrolisáveis/análise , Fenilalanina Amônia-Liase/metabolismo , Folhas de Planta/química , Ácido Salicílico/análise
11.
Food Chem ; 192: 250-9, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26304344

RESUMO

To study the interactions between natural compounds and deoxyribonucleic acid (DNA), a method has been established combining a high-performance liquid chromatography-diode array detector-multi-stage mass spectrometer with a fluorescence detector (HPLC-DAD-MS(n)-FLD). The FLD was used to monitor fluorescence intensity of the ethidium bromide-DNA (EB-DNA) complex when a compound separated by HPLC was introduced. This novel method was used to simultaneously obtain the HPLC fingerprint, UV spectra, MS(n) fragments and DNA-binding activity profile of various components in Folium Citri Reticulatae. As a result, 35 compounds were identified, of which 25 were found in the extract of Folium Citri Reticulatae for the first time, and 33 compounds showed DNA-binding activities, with the most active being feruloylhexaric and p-coumaroylhexaric acids. In addition, the precision, stability and reproducibility of this method were validated by two positive controls, quercetin and hesperidin. This new on-line method is accurate, precise and reliable for further high-throughput screening of DNA-binding compounds from food samples and other complex matrices.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Citrus/química , DNA/química , Flavonoides/análise , Fluorescência , Espectrometria de Massas/métodos , Ácidos Carbocíclicos/análise , Ácidos Carbocíclicos/química , Flavonoides/química , Hesperidina/análise , Modelos Lineares , Extratos Vegetais/química , Folhas de Planta/química , Quercetina/análise , Padrões de Referência , Reprodutibilidade dos Testes
12.
BMC Complement Altern Med ; 15(1): 422, 2015 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-26613959

RESUMO

BACKGROUND: Strobilanthes crispus is a well-known herb in Malaysia with various pharmaceutical properties. S. crispus is known to contain several biologically active chemical constituents which are responsible for its pharmaceutical quality. METHODS: Strobilanthes crispus leaves grown in three different locations in Malaysia [Kelantan (North-east), Selangor (Central), and Penang (North)], were investigated for differences in the content of secondary metabolites [total phenolics content (TPC), total flavonoids content (TFC), and total saponins content (TSC)] as well as for their antioxidant and anticancer properties. Phenolic acids and flavonoids were identified using ultra-high performance liquid chromatography (UHPLC). Ferric reducing antioxidant potential (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays were used to evaluate the antioxidant activities. The anticancer activity of extracts against HeLa cancer cell line was evaluated using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. RESULTS: Samples from the three different locations when extracted with two solvents (aqueous and ethanol extracts) yielded significantly different results for TPC, TFC, and TSC as well as for antioxidant activity. Aqueous extract of S. crispus leaves collected from Kelantan exhibited the highest values: TPC [12.62 mg gallic acid equivalents (GAE)/g dry matter (DM)], TFC (7.44 mg quercetin equivalents (QE)/g DM), TSC (44.7 mg diosgenin equivalents (DE)/g DM), DPPH (73.8 %), and FRAP (267.5 µM of Fe (II)/g) activity with a half-maximal inhibitory concentration (IC50) of 44.1 µg/mL compared to the extracts of leaves collected from the other two locations. The most important secondary metabolites identified in this study, based on concentration, were phenolics classified as followed: caffeic acid>ferulic acid>gallic acid>chlorogenic acid>trans-cinnamic acid; flavonoids: quercetin>rutin>catechin>apigenin>naringenin>kaempferol. Extracts of leaves collected from Kelantan exhibited better anticancer activity against HeLa cancer cell line with an IC50 of 182.5 µg/mL compared to the extracts of leaves from Selangor (IC50 = 266.4 µg/mL) and Penang (IC50 = 331.5 µg/mL) and to tamoxifen (IC50 = 63.4 µg/mL). S. crispus leaves with the highest content of secondary metabolites exhibited the most potent antioxidant and anticancer activity. CONCLUSIONS: Therefore, based on the potent antioxidant and anticancer activity of leaves extracts, it appears that S. crispus grown in the North-east of Malaysia (Kelantan) is a potential source of anticarcinogenic therapeutic compounds.


Assuntos
Acanthaceae , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Acanthaceae/química , Ácidos Carbocíclicos/análise , Ácidos Carbocíclicos/farmacologia , Antineoplásicos/análise , Antioxidantes/análise , Linhagem Celular/efeitos dos fármacos , Flavonoides/análise , Flavonoides/farmacologia , Células HeLa/efeitos dos fármacos , Humanos , Malásia , Compostos Fitoquímicos/análise , Extratos Vegetais/análise , Saponinas/análise , Saponinas/farmacologia
13.
Artigo em Inglês | MEDLINE | ID: mdl-25939096

RESUMO

pH-zone-refining counter-current chromatography technique for the separation of natural and synthetic mixtures has been widely used, especially for organic acids and alkaloids. Phenolic acids are very important compounds due to the potential treatment for a wide variety of diseases. However, there is not a general method for their separation. In this work, the conditions of pH-zone-refining counter-current chromatography, involving solvent systems, concentration of retainer and eluter, flow rate of mobile phase as well as sample pretreatment, were optimized to improve extraction efficiency and reduce separation time. Finally a general separation method for seven common phenolic acids has been established using pH-zone-refining counter-current chromatography. The separation of these phenolic acids was performed with a two-phase solvent system composed of methyl tert-butyl ether/acetonitrile/water at a volume ratio of 4.75: 0.25: 5, where 3mM trifluoroacetic acid was added to the organic stationary phase as a retainer and 3mM NH4OH was added to the aqueous mobile phase as an eluter. As a result, seven phenolic acids, including syringic acid, 4-hydroxyphenylacetic acid, vanillic acid, caffeic acid, p-hydroxybenzoic acid, ferulic acid and p-coumaric acid were successfully separated with the purities of 95.9%, 67.3%, 96.9%, 82.4%, 97.0%, 91.0%, and 97.2%, respectively. The established general method has been applied to the crude sample of oat bran pretreated with AB-8 resin. A total of 49.5mg of syringic acid, 109.2mg of p-coumaric acid and 184.5mg of ferulic acid were successfully purified in one run from 1.22g crude extract with the purities of 95.2%, 93.0%, and 91.8%, respectively.


Assuntos
Ácidos Carbocíclicos/análise , Ácidos Carbocíclicos/isolamento & purificação , Avena/química , Distribuição Contracorrente/métodos , Ácidos Carbocíclicos/química , Cromatografia Líquida de Alta Pressão , Extratos Vegetais/química
14.
Artigo em Inglês | MEDLINE | ID: mdl-25063924

RESUMO

Liquid chromatography coupled to mass spectrometry (MS) with electrospray ionization (ESI) is one of analytical techniques to obtain accurate results of low molecular weight aromatic compounds in biological samples of different origin. The interpretations of mass spectra of these aromatic compounds in the negative spectra registered in the full scan MS mode may be uneasy due to presence of deprotonated molecules [M-H](-) from different co-eluting entities, fragment ions created after the break-up of precursor ions and also ions representing modified molecules clusters. Thus, the first aim of this study was to evaluate general parameters during analysis performed in the full scan MS or MS/MS mode. Secondly, to set general fragmentation rules for aromatic compounds and entities in a complex biological matrix. We established that different groups of low molecular weight phenolic acids form unique adduct ions and additionally registration LC/MS/MS spectra with two different collision energies may allow for differentiating isomeric or isobaric molecules. These findings together with some general fragmentation rules can facilitate identifications of aromatic acids as we outlined in the sample of cold-pressed rose-hip oil and lupine leaves extract.


Assuntos
Ácidos Carbocíclicos/química , Aldeídos/química , Cromatografia Líquida/métodos , Extratos Vegetais/química , Espectrometria de Massas em Tandem/métodos , Ácidos Carbocíclicos/análise , Aldeídos/análise , Lupinus/química , Fenóis
15.
J Chromatogr Sci ; 52(7): 707-12, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23868179

RESUMO

A high-performance liquid chromatography method with diode array detection was developed for simultaneous analysis of organic acids (chlorogenic acid, caffeic acid, 4,5-dicaffeoylquinic acid) and flavonoids (baicalin, baicalein, wogonin) in Shuang-huang-lian injection, a traditional Chinese medicine being prescribed widely for anti-bacterial, anti-viral and immunostimulant activity. All calibration curves showed good linear correlation (r(2) > 0.9997) within the test ranges. Validation proved that the repeatability of the method was good and recovery was satisfactory. The validated method was successfully applied to 24 batches of Shuang-huang-lian injection. The result showed that there was a great variation among different samples. Principal component analysis further proved considerable variations among the samples from eight manufacturers, and suggested that chlorogenic acid and baicalin might have the greatest variations among the 24 batches. In conclusion, these results demonstrated that the method proposed was very useful for the analysis and quality consistency evaluation of Shuang-huang-lian injection.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Ácidos Carbocíclicos/análise , Cromatografia Líquida de Alta Pressão/normas , Flavonoides/análise , Limite de Detecção , Modelos Lineares , Análise de Componente Principal , Reprodutibilidade dos Testes
16.
Nat Prod Res ; 27(12): 1108-10, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22724452

RESUMO

A simple HPLC method has been used for separation and quantitative analysis of the phenolic acids in the methanolic extracts of Ligusticum mutellina aerial parts. Chlorogenic acid was the predominant phenolic acid. Additionally, gallic, p-OH-benzoic, caffeic, p-coumaric and ferulic acids were identified. Moderate antibacterial and antifungal activity (MIC = 1.25-2.5 mg mL(-1)) was observed for the methanol extract of L. mutellina herb received from plants in flowering stage against a broad spectrum of bacteria. Micrococcus luteus, Pseudomonas aeruginosa and Candida spp. were the most sensitive to this plant material. Total phenolic content for the methanol extract of L. mutellina herb received from plants in flowering stage was 1.56 g of chlorogenic acid equivalents/100 g dry weight. The methanol extract of L. mutellina herb received from plants in flowering stage showed antioxidant activity with DPPH (IC50 value of 0.40 mg mL(-1)) and with ABTS (IC50 value of 8.65 mg mL(-1)).


Assuntos
Ácidos Carbocíclicos/análise , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Ligusticum/química , Ácidos Carbocíclicos/química , Anti-Infecciosos/química , Antioxidantes/química , Candida/efeitos dos fármacos , Ácido Clorogênico/análise , Flores/química , Hidroxibenzoatos/análise , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Micrococcus luteus/efeitos dos fármacos , Componentes Aéreos da Planta/química , Extratos Vegetais/análise , Extratos Vegetais/química , Pseudomonas aeruginosa/efeitos dos fármacos
17.
Plant Foods Hum Nutr ; 66(3): 218-23, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21667145

RESUMO

The contents of total phenolic compounds, flavonoids, and phenolic acids were determined in selected garlic cultivars grown at four locations. The total phenolic content varied from 3.4 mg gallic acid equivalents (GAE)/g of dry matter (dm) to 10.8 mg GAE/g of dm with a mean value of 6.5 mg GAE/g of dm. The myricetin, quercetin, kaempferol, and apigenin flavonoids were not detected in any of the samples. Caffeic acid and ferulic acid were the major phenolic acids found with mean values of 2.9 mg/kg of dm and 2.6 mg/kg of dm, respectively. The mean contents of vanillic, p-hydroxybenzoic, and p-coumaric acids were comparable (0.4-0.8 mg/kg of dm), and the level of sinapic acid was negligible (< 0.1 mg/kg of dm). There was a significant effect of location but an insignificant effect of genotype on contents of caffeic, vanillic, p-hydroxybenzoic, and p-coumaric acids. However, genotype but not location affected the contents of total phenolics and ferulic acid. On average, the white garlic cultivars and Chinese garlic cultivars contained higher contents of total phenolics and ferulic acid than the purple garlic cultivars. However, the differences in the total phenolic content between the purple and white garlic cultivars were not significant.


Assuntos
Flavonoides/análise , Alho/química , Genótipo , Fenóis/análise , Ácidos Carbocíclicos/análise , Alho/classificação , Alho/genética , Especificidade da Espécie
18.
J Agric Food Chem ; 59(4): 1288-92, 2011 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-21250695

RESUMO

Free, esterified, glycosided, and insoluble-bound forms of eight phenolic acids in pulp, seed, and peel of jujube are separated and quantified by high performance liquid chromatography with electrochemical detection (HPLC-ECD). In the whole jujube, p-hydroxybenzoic and cinnamic acids are the most abundant phenolic acids. All quantified phenolic acids are mainly present in jujube peel. Phenolic acids in seed and peel are present in the insoluble-bound form, while, in pulp in the glycosided form, the glycosided and insoluble-bound phenolic acid fractions in jujube pulp represent the highest total phenolic content and the strongest antioxidant activity determined by DPPH and FRAP assays. Our results show that most phenolic compounds with antioxidant activity in different tissues of jujube are present as the glycosided and insoluble-bound forms.


Assuntos
Ácidos Carbocíclicos/análise , Ácidos Carbocíclicos/farmacologia , Antioxidantes/farmacologia , Frutas/química , Ziziphus/química , Benzoatos/análise , Compostos de Bifenilo , Cromatografia Líquida de Alta Pressão , Cinamatos/análise , Compostos Férricos , Indicadores e Reagentes , Oxirredução , Picratos , Sementes/química
19.
J Sci Food Agric ; 90(12): 2021-6, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20589746

RESUMO

BACKGROUND: The presence of phenolics in fruit, red wine and vinegar has positive health effects due to their significant antioxidant activity. The aim of the study was to determine the effects of two different vinegar production methods on antioxidant activity and phenolic level of vinegars derived from Ulugbey Karasi grapes. Traditional surface and industrial submerge methods were used to make vinegar. Samples were taken from fresh red grape juice, maceration, wine, traditional vinegar and industrial vinegar. RESULTS: Total phenolic content of traditional and industrial vinegar samples were 2690 mg L(-1) and 2461 mg L(-1) GAE, respectively. ORAC values of traditional and industrial vinegar samples were 10.50 micromol mL(-1)and 8.84 micromol mL(-1) TE, respectively. Antioxidant activity values of traditional and industrial vinegars were 13.50 mmol L(-1) and 10.37 mmol L(-1) TEAC, respectively. Gallic acid, catechin, epicatechin, chlorogenic acid, caffeic acid, syringic acid, p-coumaric acid and ferulic acid were detected in grape juice, wine and vinegar samples. The content of catechin in industrial vinegar (27.50 mg L(-1)) was significantly higher than that of in traditional vinegar (13.76 mg L(-1)) (P < 0.05). Traditional vinegar had higher amounts of chlorogenic and syringic acids than the industrial vinegar (P > 0.05). CONCLUSION: Results of this study showed that different production methods affected the functional constituents of wine vinegars.


Assuntos
Ácido Acético/farmacologia , Antioxidantes/farmacologia , Manipulação de Alimentos/métodos , Fenóis/farmacologia , Preparações de Plantas/química , Vitis/química , Ácido Acético/química , Ácidos Carbocíclicos/análise , Ácidos Carbocíclicos/farmacologia , Antioxidantes/análise , Ácidos Cumáricos/análise , Ácidos Cumáricos/farmacologia , Flavonoides/análise , Flavonoides/farmacologia , Frutas , Fenóis/análise , Vinho
20.
Electrophoresis ; 31(12): 2070-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20503201

RESUMO

Free-flow electrophoresis (FFE), a preparative free zone electrophoretic method, was used offline in conjunction with ultrahigh-resolution FT/ion cyclotron resonance -MS to resolve the complexity of Suwannee River fulvic acid (SRFA). Before MS, the FFE separation conditions and the compatibility with ESI were optimized. The constituents in SRFA were effectively separated based on their charge states and sizes. The obtained mass spectra were compared by means of van Krevelen diagrams and the calculated aromaticity indices of the individual constituents were used to describe the distribution of aromatic/unsaturated structures across the FFE-fractionated samples. The consolidated number of ions observed within the individual SRFA fractions were much higher than those of the bulk samples alone, demonstrating extensive ion suppression effects in bulk SRFA likely also operating in the analysis of complex biogeochemical mixtures in flow injection mode. The FFE approach allows for producing sizable amounts of sample from dilute solutions, which can be easily fractionated into dozens of individual samples with the possibility of further in-depth characterization.


Assuntos
Benzopiranos/análise , Eletroforese/métodos , Análise de Fourier , Substâncias Húmicas/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Ácidos Carbocíclicos/análise , Ácidos Carbocíclicos/química , Benzopiranos/química
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