RESUMO
A systematic study of extraction efficiency of polyphenolic compounds from the most widespread Boraginaceae species was carried out. The optimal extraction was achieved with 50 % (V/V) methanol for phenolic acids and flavonoids, 0.2 % (V/V) HCl in 50 % (V/V) methanol for anthocyanins and pure water for flavan-3-ols. The distribution and diversity of polyphenolic compounds in plant material obtained from wild-growing Anchusa officinalis, Cynoglossum creticum Mill., Echium vulgare, Echium italicum, and Onosma heterophylla Griseb. species from Macedonia was also assessed. These widespread Boraginaceae species contain phenolic acid derivatives, flavonoids, flavan-3-ols and anthocyanins and in total 31 of them were identified, from which 22 were first identified in the representative species, and 6,8-di-C-glucosides of apigenin and luteolin were identified for the first time in Boraginaceae. The profiles of polyphenolic compounds for each sample were obtained and their phytochemical profile established. The potential for further bioactivity studies of Anchusa officinalis and Cynoglossum creticum containing up to 24577.05â µg/g and 14304.15â µg/g of total polyphenols were assumed to be highest, followed by Echium vulgare (from 6382.61 to 14114.33â µg/g), Onosma heterophylla (9463.97â µg/g) and Echium (4108.14â µg/g).
Assuntos
Boraginaceae , Boraginaceae/química , Antocianinas , Metanol , Fenóis/química , Flavonoides/química , Extratos Vegetais/química , Antioxidantes/químicaRESUMO
Bulgaria and North Macedonia have a long history of the production and use of honey; however, there is an obvious lack of systematic and in-depth research on honey from both countries. The oak honeydew honey is of particular interest, as it is highly valued by consumers because of its health benefits. The aim of this study was to characterize honeydew and floral honeys from Bulgaria and North Macedonia based on their NMR profiles. The 1D and 2D 1H and 13C-NMR spectra were measured of 16 North Macedonian and 22 Bulgarian honey samples. A total of 25 individual substances were identified, including quinovose, which was found for the first time in honey. Chemometric methods (PCA-principal component analysis, PLS-DA-partial least squares discriminant analysis, ANOVA-analysis of variance) were used to detect similarities and differences between samples, as well as to determine their botanical and geographical origin. Semiquantitative data on individual sugars and some other constituents were obtained, which allowed for the reliable classification of honey samples by botanical and geographical origin, based on chemometric approaches. The results enabled us to distinguish oak honeydew honey from other honey types, and to determine the country of origin. NMR was a rapid and convenient method, avoiding the need for other more time-consuming analytical techniques.
Assuntos
Análise de Alimentos/métodos , Mel/análise , Espectroscopia de Ressonância Magnética/métodos , Bulgária , Quimioinformática/métodos , Flores , Análise de Alimentos/estatística & dados numéricos , Análise dos Mínimos Quadrados , Espectroscopia de Ressonância Magnética/estatística & dados numéricos , Análise de Componente Principal , República da Macedônia do Norte , Açúcares/análiseRESUMO
Honey contaminated with pyrrolizidine alkaloids (PAs) could pose a risk for human consumption, being a widely consumed food product. A fast and simple LC/MS method for the analysis of pyrrolizidine alkaloids in honey was optimised to collect occurrence data. The extraction efficiency was evaluated by a systematic study of multiple solvent mixtures and clean-up procedures. The best results for PA extraction were obtained using a formic acid/methanol mixture with subsequent clean-up by the QuEChERS method, resulting in a mean recovery range of 91.8-102%. The method validation showed satisfactory intra-day (RSD < 5.1%) and inter-day precision (RSD < 9.1%). The proposed method was applied to 14 samples. A total of six PAs and two N-oxides were detected, with levels between 89 and 8188 µg/kg. This assessment highlights the potential risk of intoxication and the need for further investigations regarding an effective quality system for manufacturers to control PAs in honey.
Assuntos
Mel , Alcaloides de Pirrolizidina , Cromatografia Líquida de Alta Pressão , Contaminação de Alimentos/análise , Mel/análise , Alcaloides de Pirrolizidina/análise , Espectrometria de Massas em Tandem/métodos , República da Macedônia do NorteRESUMO
Hypericum perforatum L. is a medicinal plant considered as an important natural source of secondary metabolites with a wide range of pharmacological attributes. Hairy roots (HR) were induced from root segments of in vitro grown seedlings from H. perforatum after cocultivation with Agrobacterium rhizogenes A4. Investigations have been made to study the production of phenolic compounds in dark-grown (HR1) and photoperiod-exposed (HR2) cultures. The chromatographic analysis of phenolic acids, flavonols, flavan-3-ols, and xanthones revealed marked differences between HR1 and HR2 cultures. The production of quinic acid, kaempferol, and seven identified xanthones was increased in HR2. Moreover, HR2 showed a capability for de novo biosynthesis of two phenolic acids (3-p-coumaroylquinic acid and 3-feruloylquinic acid), three flavonol glycosides (kaempferol hexoside, hyperoside, and quercetin acetylglycoside), and five xanthones (tetrahydroxy-one-methoxyxanthone, 1,3,5-trihydroxy-6-methoxyxanthone, 1,3,5,6-tetrahydroxy-2-prenylxanthone, paxanthone, and banaxanthone E). On the other side, HR1 cultures were better producers of flavan-3-ols (catechin, epicatechin, and proanthocyanidin dimers) than HR2. This is the first comparative study on phenolic profile of H. perforatum HR cultures grown under dark and photoperiod conditions.
Assuntos
Hypericum/metabolismo , Fenóis/metabolismo , Agrobacterium/crescimento & desenvolvimento , Agrobacterium/metabolismo , Cromatografia Líquida de Alta Pressão , Escuridão , Flavonoides/metabolismo , Hidroxibenzoatos/metabolismo , Hypericum/crescimento & desenvolvimento , Hypericum/efeitos da radiação , Estrutura Molecular , Fenóis/química , Fotoperíodo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/efeitos da radiação , Plantas Medicinais/crescimento & desenvolvimento , Plantas Medicinais/metabolismo , Plantas Medicinais/efeitos da radiação , Espectrometria de Massas por Ionização por Electrospray , Técnicas de Cultura de Tecidos , Xantonas/metabolismoRESUMO
Sideritis scardica Griseb. is a Balkan endemic species traditionally used for the treatment of pulmonary emphysema and angina pectoris. Recent research has also shown its phytotherapeutic potential as an anticancer and neuroprotective agent. These findings, as well as the endangered status of the species in its wild habitats, have motivated the present research on application of plant cell tissue and organ culture for the purposes of both valuable germplasm conservation and secondary metabolites production. Shoot cultures of the plant were initiated from sterile germinated seeds and the effects of activated charcoal (AC), as well benzyl adenine and 1-naphthaleneacetic acid treatments, were experimented. The phenolic profile analysis was performed by HPLC/DAD/MSn. Comparison with samples collected from wild plants in their natural habitat was performed. It was established that in vitro multiplication induced by plant growth regulators (PGRs) was accompanied by a higher impairment of leaf morphology and trichome formation, as well as by the occurrence of plantlet hyperhydricity and callus formation, as compared with the AC treatments. Shoot culture-derived plant material was shown to produce two phenylethanoids and five flavone glycosides, not detected in the wild collected plant material. In addition, the two types of in vitro culture treatments led to the stimulation of either flavone glycosides or phenylethanoids in the in vitro cultivated plants. Thus, AC stimulated, to a higher extent, flavone glycosides' accumulation, leading to an elevated flavone/phenylethanoid ratio, as compared with PGR treatments.
RESUMO
Phenolic compounds and colour stability of red wines produced from Vranec Vitis vinifera L. grape variety were investigated by means of different maceration times (3, 6 and 10 days), two doses of SO2 (30 and 70 mg/L SO2), two yeasts for fermentation (Vinalco and Levuline), temperature of storage and time of aging (3, 6 and 16 months). In general, maceration time influenced the phenolics extraction from the grapes into the wine. Highest concentrations of phenolic components were observed in the wines produced with 6 days of maceration, except for the flavan-3-ols which were present in highest amounts in the wines macerated for 10 days. Higher doses of SO2 increased the extraction of polyphenols, preventing the wines from oxidation, while the effect of yeast on phenolics extraction was not significant. Wine aging affected the phenolic content of wines produced with 3 days of maceration and caused intensive decrease of anthocyanins during the storage period. Wines aged at higher temperature showed lower anthocyanin levels and less intense coloration. Principal component analysis revealed that separation of the wines was performed according to the hue value in correlation with the maceration time and time of wine aging.
RESUMO
Coenzyme Q10 (CoQ10) is one of the essential components of the mitochondrial electron-transport chain (ETC) with the primary function to transfer electrons along and protons across the inner mitochondrial membrane (IMM). The concomitant proton gradient across the IMM is essential for the process of oxidative phosphorylation and consequently ATP production. Cytochrome P450 (CYP450) monoxygenase enzymes are known to induce structural changes in a variety of compounds and are expressed in the IMM. However, it is unknown if CYP450 interacts with CoQ10 and how such an interaction would affect mitochondrial function. Using voltammetry, UV-vis spectrometry, electron paramagnetic resonance (EPR), nuclear magnetic resonance (NMR), fluorescence microscopy and high performance liquid chromatography-mass spectrometry (HPLC-MS), we show that both CoQ10 and its analogue CoQ1, when exposed to CYP450 or alkaline media, undergo structural changes through a complex reaction pathway and form quinone structures with distinct properties. Hereby, one or both methoxy groups at positions 2 and 3 on the quinone ring are replaced by hydroxyl groups in a time-dependent manner. In comparison with the native forms, the electrochemically reduced forms of the new hydroxylated CoQs have higher antioxidative potential and are also now able to bind and transport Ca(2+) across artificial biomimetic membranes. Our results open new perspectives on the physiological importance of CoQ10 and its analogues, not only as electron and proton transporters, but also as potential regulators of mitochondrial Ca(2+) and redox homeostasis.
Assuntos
Cálcio/metabolismo , Ubiquinona/metabolismo , Transporte Biológico , Membrana Celular/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Eletroquímica , Humanos , Concentração de Íons de Hidrogênio , Hidroxilação , Hidróxido de Sódio/química , Espectrofotometria , Ubiquinona/químicaRESUMO
An isocratic High Performance Liquid Chromatographic (HPLC) method was optimized for 3-phenoxybenzyl (1RS)-cis-trans-3-(2,2-dichlorovinyl)-2,2-dimethyl-cyclopropanecarboxylate (permethrin) residues identification and quantification in wine matrix. Analytical reverse phase (RP) C-18 column was used (25 cm × 4 mm i.d., 5 µ m) with mobile phase consisting of acetonitrile and water in ratio 70 %/30 % (v v(-1)), flow-rate 2.0 mL min(-1), UV-detection at 215 nm and controlled oven temperature at 25°C. The peaks of isomers were identified with the retention times as compared to standard cis-/trans- mixture and confirmed with characteristic spectra using photodiode array detector. Under these conditions, permethrin isomers were well separated with resolution 2.8 and no interference with the naturally present wine compounds was observed. The method was validated for linearity, precision, accuracy, limit of detection (LOD) and limit of quantification (LOQ). Linear regression analysis data proved a good linear relationship (correlation coefficients, r(2), for cis- and trans-isomer are: 0.9995 and 0.9997, respectively) between response of the detector and concentration of permethrin isomers over a wide concentration range for both isomers (0.55 mg L(-1) -4.40 mg L(-1)). Experimental data showed mean recoveries between 93.95% and 96.58% with RSD values in range: 0.89% -3.69%. The effect of ethanol content in the solvent on permethrin isomers peak areas was also studied and 60% v v(-1) ethanol was found to be optimal for sample preparation. The method was successfully tested on 20 commercial wine samples from the market in which no permethrin was detected. Thus, it was proved that it is suitable for routine permethrin residues analysis. The proposed method is suitable for routine analysis because of the simple sample preparation, acceptable run-time, low cost and its applicability with conventional instruments.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Permetrina/química , Resíduos de Praguicidas/química , Vinho/análise , Contaminação de Alimentos/análise , IsomerismoRESUMO
A simple, rapid and precise HPLC method has been developed for the assay of verapamil in human plasma. The clean up of the plasma samples was tested using several adsorbents for solid-phase extraction and best recovery was obtained using mixed-mode cartridges (HLB - hydrophilic-lipophilic balance) ranging between 94.70 and 103.71%. HPLC separation was performed with isocratic elution on Lichrospher 60 RP-select B column (250 mm x 4 mm I.D., 5 microm particle size). The mobile phase was 40% acetonitrile and 0.025 mol/L KH2PO4 with pH 2.5 at flow rate of 1 mL/min. Diltiazem was used as internal standard and the detection wavelength was 200 nm. The calibration curves were linear in the range of 10-500 ng/mL. The developed method is convenient for routine analysis of verapamil in human plasma.
Assuntos
Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Extração em Fase Sólida/instrumentação , Extração em Fase Sólida/métodos , Verapamil/sangue , Calibragem , Humanos , Concentração de Íons de Hidrogênio , Estrutura Molecular , Verapamil/químicaRESUMO
Flavonoids obtained from Sideritis species (Lamiaceae), S. raeseri and S. scardica, grown in Macedonia were studied. Qualitative and quantitative analyses of the flavonoid aglycones were performed using high-performance liquid chromatography (HPLC) with a UV diode array detector. Extracts were prepared by acid hydrolysis in acetone, re-extraction in ethyl acetate and evaporation to dryness; the residue dissolved in methanol was subjected to HPLC analysis.Isoscutellarein, chryseriol and apigenin were identified in the extracts. Also, a 4'-methyl ether derivative of isoscutellarein was found, together with hypolaetin and its methyl ether derivative, which were identified according to previously isolated glycosides and literature data. Quantitation was performed using calibration with apigenin.According to this screening analysis, the samples of the genus Sideritis from Macedonia are rich in polyhydroxy flavones and analogous with the previously studied Mediterranean Sideritis species from the Ibero-North African and Greek Sideritis species with respect to the presence of 8-OH flavones and their derivatives.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/análise , Sideritis/química , Espectrofotometria Ultravioleta/métodos , Apigenina/análise , Apigenina/química , Apigenina/isolamento & purificação , Flavonas/análise , Flavonas/química , Flavonas/isolamento & purificação , Flavonoides/química , Flavonoides/isolamento & purificação , Grécia , Estrutura Molecular , Componentes Aéreos da Planta/química , Extratos Vegetais/análise , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Especificidade da EspécieRESUMO
The essential oils of two species of Sideritis growing spontaneously in Bulgaria and Macedonia are reported, Sideritis scardica and Sideritis raeseri. The oils of S. scardica from different locations differed significantly: in the Macedonian sample alpha-cadinol (20%) predominated, while in the oil of Bulgarian samples the main components were diterpenic compounds and octadecenol (over 20%). This is the first report of ditrpenoids in essential oil of S. scardica. The oil of S. raeseri demonstrated a distinct chemical profile with its high concentration of sesquiterpenes, main components being germacrone (25%) and elemol acetate (15.9%). The observed qualitative variability of the oil composition of S. scardica of different geographic origin could be a result of different ecologic conditions but might also reflect the well-known tendency of some Sideritis species to hybridize.
Assuntos
Óleos Voláteis/química , Sideritis/química , Bulgária , Grécia , Especificidade da Espécie , Terpenos/análiseRESUMO
Qualitative and quantitative analyses of polyphenols extracted from 21 Malus domestica cultivars using ultra high performance liquid chromatography with diode array detection coupled to heated electrospray ionization mass spectrometric detection was performed for separation of 27 phenolic compounds on a reversed phase UHPLC column with an optimized gradient consisting of 1% formic acid in water and 1% formic acid in methanol within 20 minutes. According to retention times, UV maxima and mass spectra of the peaks in the chromatograms obtained from extracts of apple peel, flesh and leaves, the polypfienolic compounds were identified and quantified. Based on fragmentation patterns, 6 phenolic acids, 5 flavan-3-ols, 5 dihydrochalcones, 8 flavonols and 3 flavone derivatives were characterized in the studied samples. The method was then employed for analysis of the polyphenolic pattern of 21 apple cultivars, both commercial and autochthonous for the Macedonian region, as well as for monitoring the influence of long term storage on the polyphenolic content and composition of apple fruits and for comparison of polyphenolic profiles of apple cultivars during two years of harvesting. The obtained results revealed minor differences in the quality and major variation in the content of phenolic compounds in the flesh, peel and leaves in the studied apple cultivars that is attributed mainly to cultivar differences and meteorological factors.
Assuntos
Frutas/química , Malus/química , Folhas de Planta/química , Polifenóis/química , Cromatografia Líquida de Alta Pressão , Armazenamento de Alimentos , Espectrometria de Massas , Extratos Vegetais/química , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria UltravioletaRESUMO
Samples of Thymus alsarensis Ronniger, an endemic species for the Allchar locality, were evaluated for their polyphenolic composition and heavy metals. Allchar district is an abandoned antimony-arsenic-thallium deposit in the north-west of Kozuf Mountain, R. Macedonia, with a unique mineral composition affecting the mineral composition of the flora. A systematic method for phenolic compounds characterization was developed using mass spectrometry coupled to HPLC/DAD. Analyses were focused on the polyphenolic compounds to establish a possible correlation to the region specific heavy metals As and TI in the different organs of T. alsarensis. Twenty-seven polyphenols: phenolic acid derivatives and flavonoid glycosides of luteolin, apigenin, quercetin, and kaempferol were detected; contents were higher in the leaves and flowers compared with stems and roots. Quinic acid (1), prolithospermic acid (6), salvianolic acid B (7), salvianolic acid A (8), monomethyl lithospermate (9), luteolin dihexoside (12), luteolin pentosyl-hexoside (14), luteolin acetyl pentosyl-hexoside (16), luteolin acetyl hexoside (17), luteolin dipentoside (21), luteolin pentoside (24), luteolin acetyl dipentoside (25), kaempferol pentosyl-hexoside (19) and kaempferol acetyl pentosyl-hexoside (22) were detected in T. alsarensis for the first time. To assay the content of As and TI, root, stem, leaf and flower samples were analyzed by inductively coupled plasma atomic emission spectrometry (ICP-AES). Significant accumulation of As and TI was observed with As content from 0.25 to 140 mg/kg and TI from 0.10 to 496 mg/kg. The content of As was much higher in the roots, while the content of TI was significantly higher in the roots, flowers and leaves in all T. alsarensis specimens. Comparison of the results obtained for total polyphenols and for As and TI content does not suggest any correlation (positive or negative) between the total phenolic content and the content of TI and As. On the other hand, it is evident that the soil rich with specific heavy metals (TI and As) affects the type of polyphenolic compounds produced in different organs, compared with other Thymus species growing on soil that is not contaminated.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Metais Pesados/análise , Fenóis/análise , Tálio/análise , Thymus (Planta)/química , Arsênio/análise , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria AtômicaRESUMO
Two extraction methods for subsequent gas chromatographic (GC) determination of volatiles from freshly harvested and aged fennel fruit samples (Foeniculum vulgare Mill.,ssp. vulgare var. dulce) have been compared. Hydrodistillation followed by GC-FID and GC-MS analysis was used as a standard method for essential oil characterization, while static headspace followed by GC (SHS-GC-FID) was used as a comparative method for determination of volatile components. As the fennel fruit ages, there is a gradual loss of the volatile components as indicated by the lower yield of essential oil and lower content of volatiles, as indicated by the alternative SHS-GC-FID analysis. Slight differences observed for the main components (trans-anethole, estragole, fenchone, and limonene) using the two methods are negligible, indicating that these volatiles did not undergo chemical transformation during the sample preparation procedures. A difference in anisaldehyde content was observed when the composition of the hydrodistilled essential oil was compared with the SHS-GC-FIDanalysis of volatiles and explanation for the variation of anisaldehyde content and the origin of other compounds was suggested. Comparison of the obtained results showed that limonene oxides, carvone and carveolare detectable in SHS-GC-FID analysis of the aged fennel fruits, while in hydrodistilled samples analyzed by GC-FID they were not present. Another observed difference was the appearance of products in significant amounts with higher retention times than trans-anethole, namely threo- and erythro-anethole ß-hydroxymethylether and anethole glycol that are not detectable in the essential oil obtained by hydrodistillation. So, the relative abundance of the major components is comparable between these two methods for fennel seed up to 3 years from harvest and they can be used interchangeably depending on the purpose and amount of material. Furthermore, SHS-GC-FID can be used for assessment of maximum storage time and quality of fennel fruit suitable for human consumption.
Assuntos
Destilação/métodos , Foeniculum/química , Análise de Alimentos/métodos , Frutas/química , Compostos Orgânicos Voláteis/química , Manipulação de Alimentos , Fatores de TempoRESUMO
Coenzyme Q-0 (CoQ-0) is the only Coenzyme Q lacking an isoprenoid group on the quinoid ring, a feature important for its physico-chemical properties. Here, the redox behavior of CoQ-0 in buffered and non-buffered aqueous media was examined. In buffered aqueous media CoQ-0 redox chemistry can be described by a 2-electron-2-proton redox scheme, characteristic for all benzoquinones. In non-buffered media the number of electrons involved in the electrode reaction of CoQ-0 is still 2; however, the number of protons involved varies between 0 and 2. This results in two additional voltammetric signals, attributed to 2-electrons-1H(+) and 2-electrons-0H(+) redox processes, in which mono- and di-anionic compounds of CoQ-0 are formed. In addition, CoQ-0 exhibits a complex chemistry in strong alkaline environment. The reaction of CoQ-0 and OH(-) anions generates several hydroxyl derivatives as products. Their structures were identified with HPLC/MS. The prevailing radical reaction mechanism was analyzed by electron paramagnetic resonance spectroscopy. The hydroxyl derivatives of CoQ-0 have a strong antioxidative potential and form stable complexes with Ca(2+) ions. In summary, our results allow mechanistic insights into the redox properties of CoQ-0 and its hydroxylated derivatives and provide hints on possible applications.
Assuntos
Ubiquinona/química , Antioxidantes/química , Soluções Tampão , Eletroquímica , Hidróxidos/química , Oxirredução , Análise Espectral , Água/químicaRESUMO
The chemical composition and antioxidant activity of different extracts (diethyl ether, ethyl acetate and n-butanol) obtained from Teucrium species (T. chamaedrys, T. montanum, T. polium) were investigated in this work. Phytochemical screening of the plant extracts proved the presence of flavonoids luteolin, apigenin and/or diosmetin. The chemical composition of extracts was evaluated by HPLC and spectrophotometry. Antioxidant activities of the extracts were evaluated using three complementary in vitro assays: inhibition of DPPH (1,1-diphenyl-2-picrylhydrazyl) radical, inhibition of hydroxyl radicals and protection of beta-carotene-linoleic acid model system. In the first two assays, strong inhibitory activity was shown by T. montanum and T. chamaedrys extracts. In the beta-carotene-linoleic acid model system, extracts from T. polium showed remarkable activity. These findings demonstrated that Teucrium species possess free radical and hydroxyl radical scavenging activity as well as antioxidant activity in vitro.
Assuntos
Antioxidantes/química , Teucrium/química , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/química , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Hidrazinas/química , Radical Hidroxila/química , Indicadores e Reagentes , Ácido Linoleico/química , Oxidantes/química , Picratos , Extratos Vegetais/química , Solventes , Especificidade da Espécie , Espectrofotometria Ultravioleta , beta CarotenoRESUMO
Cultivated and wild growing samples of fennel (Foeniculum vulgare Mill., Apiaceae) from R. Macedonia were studied for their volatiles and fatty acid composition. The main essential oil components isolated via hydrodistillation were: trans-anethole (>80%), estragole (< 6%), limonene (< 6%), anisaldehyde (< 1%) and 0.5 % fenchone. An alternative method for characterization of both the non-polar volatile and non volatile fractions was developed using n-hexane and dichloromethane (3:1, v/v) in a Soxhlet extraction followed by transesterification. The obtained extracts were then characterized and the dominant fatty acid was 18:1 (petroselinic and oleic acid) 75.0-82.8%, followed by 18:2 (linoleic acid) 10.8-16.2% and other fatty acids: palmitic (4.3-6.9%), stearic (1.2-1.7%) and myristic (0-2.9%). The results for the volatile fraction after Soxhlet extraction and transesterification did not significantly differ from results obtained after hydrodistillation, especially for the main components (trans-anethole, estragole, fenchone and limonene), implying that the developed method can be used for simultaneous determination of volatiles and fatty acids.
Assuntos
Cromatografia Gasosa/métodos , Ácidos Graxos/química , Foeniculum/química , Óleos Voláteis/química , Óleos de Plantas/química , Cromatografia Gasosa/instrumentaçãoRESUMO
Flavonoids and other phenolic compounds in young needles of four pine species, Pinus peuce, P. nigra, P. mugo and P. sylvestris from the Macedonian flora were investigated. The amount of total phenols and total flavonoids were determined using Folin-Ciocalteau and aluminum chloride assay, respectively. The obtained results revealed that the total phenolic content (TPC) and total flavonoids content (TFC) varied among different pine species ranging from 9.8 to 14.0 mg GAE/g and from 3.3 to 7.2 mg CE/g of dried plant material, respectively. Qualitative analysis of flavonoids and other phenolic components was made by a LC-DAD/ESI-MS(n) optimized chromatographic method. A total of 17 phenolic components were identified and classified as: acids (2), procyanidins (2) and flavonoid glycosides (13). The most prevalent components were flavonoid glycosides, especially flavonols and methylated flavonols (9). Additionally, 3 components were found as acylated flavonol glycosides with ferulic and p-coumaric acid. The last one was found not only in esterified form but also in the free form. Only one flavone-apigenin glycoside was detected. Procyanidins were identified as catechin derivatives, both dimers and trimers.
Assuntos
Flavonoides/química , Fenóis/química , Pinus/química , Extratos Vegetais/química , Flavonoides/isolamento & purificação , Fenóis/isolamento & purificação , Pinus/classificação , Extratos Vegetais/isolamento & purificação , República da Macedônia do NorteRESUMO
A new simple and rapid high-performance liquid chromatographic (HPLC) method with UV detection for the determination of indapamide in biological fluids has been developed. Indapamide and internal standard were isolated from serum and whole blood samples by solid-phase extraction with RP select B cartridges. The chromatographic separation was accomplished on a reversed-phase C(8) column with a mobile phase composed of 0.1% (v/v) triethylamine in water (pH 3.5) and acetonitrile (63:37, v/v). UV detection was set at 240 nm. The calibration curves were linear in the concentration range of 10.0-100.0 ng/ml for serum, and 50.0-500.0 ng/ml for whole blood, and the limits of quantification were 10.0 and 50.0 ng/ml, respectively.
Assuntos
Anti-Hipertensivos/sangue , Cromatografia Líquida de Alta Pressão/métodos , Indapamida/sangue , Calibragem , Humanos , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
In the present work, the polyphenolic profile and content of four Teucrium species (T. chamaedrys L., T. montanum L., T. polium L., T. scordium L.) from the Macedonian flora were examined. A LC/DAD/ESI-MS(n) chromatographic method was optimized and 31 phenolic compounds were identified, quantified and classified into four groups: hydroxycinnamic acid derivatives (2), phenylethanoid glycosides (12), flavonoid glycosides (11) and flavonoid aglycones (6). The total phenolic content (mg/g dry herb) ranged from 28.2 (T. montanum), 30.9 (T. scordium), 35.1 (T. polium) to 52.1 (T. chamaedrys). Phenylethanoid glycosides were the predominant group ofpolyphenols in the studied samples contributing 60% of the total phenolic content for T. polium and T. scordium and around 90% for T. montanum and T. chamaedrys. The systematic analysis for identification and quantification of all present phenolic compounds contributes to the chemotaxonomy of the investigated Teucrium species and to the valorization based on their phenolic profiles and content.