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1.
Food Chem ; 305: 125457, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31505414

RESUMO

Taking into account a growing market and small number of articles related to honeydew honey, a metabolomic approach associated with multivariate analysis and modelling was proposed to discriminate five varieties of honey. Advanced analytical techniques were used for determination of 20 elements, 14 carbohydrates and stable carbon isotope ratio. No chemical marker has been found within sugar compounds, but several elements (Ba, Ca, Mg, Sr, Mn, Al, Co, Ni, Se) were marked as characteristic of honey type and allow classification of three botanical origins (Abies alba, Quercus frainetto, Quercus ilex). Sugars turanose, trehalose, arabinose and raffinose, elements Ba, Sr, P, Cd and Se, and δ13C values of honey, have different concentrations in honeys of the same botanical origin but harvested in different season. In addition to a confirmation of authenticity in terms of production, the values of δ13C of protein could be a good indicator of botanical origin.

2.
Biomolecules ; 9(12)2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31779186

RESUMO

Information on compositional, nutritional and functional properties of bee-pollen, as a health-promoting food, is essential for defining its quality. Concerning the nutritional importance of phenolic compounds, the aim of this study was to determine the phenolic profile and antioxidant activity of twenty-four bee-pollen samples collected from different regions of Serbia. High-performance thin-layer chromatographic (HPTLC) fingerprinting was used for profiling of bee-pollen samples according to the botanical type. HPTLC hyphenated with image analysis and a pattern recognition technique confirmed the grouping of samples caused by the specific phenolic composition of pollens of different botanical origin. Flavonoid glycosides in bee-pollen samples were identified by applying ultra-high-performance liquid chromatography (UHPLC) coupled with linear ion trap-Orbitrap mass spectrometry (LTQ Orbitrap MS). Eight out of twenty-seven flavonol glycosides were identified in bee-pollen samples for the first time. All analyzed bee-pollen samples showed a high number of phenolic compounds which may have therapeutic potential.

3.
J AOAC Int ; 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31511123

RESUMO

Phytochemical analysis, the chemical investigation of plants, is a rapidly developing chemical discipline with various goals such as the determination of the substance classes and the isolation and qualitative and/or quantitative analyses of bioactive compounds or their structural analysis. The analysis of plants begins with optimizing extraction procedures because they play a key role in extraction outcomes, i.e., the isolation of bioactive compounds from natural products and the selection of the subsequent tests used in the analyses. The extraction is a critical step because it is necessary to extract the desired components of the complex natural matrix without destroying them. A wide range of techniques for the extraction of bioactive compounds from natural matrixes are currently available. This review aims to describe and compare the most commonly used methods, traditional/conventional and innovative/green. It will focus on the principles behind each method and on their strengths and limitations in order to help evaluate their suitability and economic feasibility, highlighting the advantages of new innovative techniques over conventional extraction procedures. Finally, the recent application of deep eutectic solvents as a new, eco-friendly method for the extraction of bioactive compounds from natural matrixes is also discussed.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31200246

RESUMO

Reversed-phase thin-layer chromatography and micellar thin-layer chromatography were used in order to investigate retention behaviour and to determine lipophilicity of series of 2-(methoxy)phenylpiperazine dopamine D2 ligands with different size, shape and rigidity. The retention mechanism was discussed. The lipophilicity parameters obtained in conventional reversed-phase systems expressed as RM0 and C0, as well as RM values determined in microemulsion reversed-phase systems were correlated with in silico determined lipophilicity values. In silico pharmacokinetic properties of 2-(methoxy)phenylpiperazine dopamine D2 ligands revealed the importance of experimentally determined lipophilicity values besides the molecular weight, on the blood-brain barrier permeability process. Also, the experimentally determined lipophilicity was found as a very important factor in plasma protein binding process of 2-(methoxy)phenylpiperazine dopamine D2 ligands. Besides, the Lipinski's rule of five indicates that examined ligands satisfy the criterion of drug-like molecules. The principal component analysis was performed on the experimentally determined and calculated lipophilicity values as well on the molecular descriptors which describe the pharmacokinetic properties in order to provide basic insights into similarities among the studied ligands.

5.
Food Chem ; 274: 629-641, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30372988

RESUMO

Concerning the particular nutritive value of honeydew honey compared to blossom honey, and small number of studies defining botanical origin of honeydew honey, comprehensive analysis of phenolic profile of 64 honeydew honey samples of specific botanical origin was performed. Two advanced techniques of liquid chromatography hyphenated with mass spectrometry were used for identification of a total of 52 compounds and quantification of 25 of them. Pattern recognition analysis applied on data on phenolic compounds content confirmed that quercetin, naringenin, caffeoylquinic acid, hydroxyphenylacetic acid, apigenin and genistein, could be considered as potential markers of botanical origin of honeydew honey. Spectroscopic and electrochemical approaches were applied for the evaluation of the antioxidant capacity. Quercus sps. samples, Quercus frainetto and Quercus ilex, showed high biological activity and specific chemical composition. Additionally, cyclic voltammetry profiles were used for characterization and natural clustering of honeydew honey for the first time.


Assuntos
Antioxidantes/química , Mel/análise , Fenóis/análise , Quercus/química , Cromatografia Líquida de Alta Pressão , Análise por Conglomerados , Técnicas Eletroquímicas , Espectrometria de Massas , Valor Nutritivo , Análise de Componente Principal , Quercus/metabolismo
6.
Arh Hig Rada Toksikol ; 69(3): 264-274, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30285946

RESUMO

To contribute to the development of urban beekeeping, we designed this study to obtain more information about the contamination of urban bee products with toxic metals, polycyclic aromatic hydrocarbons (PAHs), and pesticides. The samples of honey (N=23), pollen (N=13), and floral nectar (N=6) were collected from the experimental stationary apiary of the Belgrade University Faculty of Agriculture located in centre of Zemun (a municipality of the Belgrade metropolitan area) in 2015 and 2016. Metals (Pb, Cd, As, Cu, Zn, Fe, Mn, Ni, Cr, and Hg) were determined with inductively coupled plasma quadrupole mass spectrometry (ICP-QMS). Polycyclic aromatic hydrocarbons (PAHs) were analysed with high-performance liquid chromatography with fluorescence detection (HPLC-FLD). Pesticides were analysed with gas chromatography - mass spectrometry (GC-MS). The honey samples were generally within the European and Serbian regulatory limits. The levels of all the 123 analysed pesticides were below the limit of quantification (LOQ). Regarding PAH levels in honey, the highest content was found for naphthalene. The elevated levels of Hg and Cr and of PAHs in the pollen samples indicated air pollution. Pesticide residues in pollen, however, were below the LOQ. In nectar, metal levels were relatively similar to those in honey. Our results suggest that the investigated urban honey meets the regulatory requirements for metals, PAHs, and pesticides and is therefore safe for consumption.

7.
J Sci Food Agric ; 2018 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-29936700

RESUMO

BACKGROUND: The compositional, functional, and nutritional properties of fruits are important for defining their quality. Fruit seeds should be better exploited as they are also considered to be a good source of bioactive components. Twenty macro, micro, and trace elements were identified and quantified in the seeds of 70 genuine wild and cultivated fruit species/cultivars by inductively coupled plasma atomic emission spectrometry and inductively coupled plasma mass spectrometry. Sophisticated chemometric techniques were also used to establish criteria for the classification of the analyzed samples. RESULTS: Calcium and P were the most abundant elements, followed by K and Na. The content of microelements and trace elements differed among the different cultivars/genotypes. The content of Ba, Pb, and Sr was significantly higher in wild fruits, whereas Fe, Mg, Mn, Ni and Zn content was higher in cultivated fruits. CONCLUSION: All of the statistical procedures that were used - Kruskal-Wallis, Mann-Whitney U-test, and principal component analysis (PCA) - confirm a unique set of parameters that could be used as phytochemical biomarkers to differentiate fruit-seed samples belonging to different cultivars/genotypes according to their botanical origin. This kind of investigation may contribute to intercultivar/genetic discrimination and may enhance the possibilities of acquiring a valuable authenticity factor. © 2018 Society of Chemical Industry.

8.
J Ethnopharmacol ; 222: 148-158, 2018 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-29733941

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Trapa natans L. (water chestnut or water caltrop) is a widespread aquatic plant, which has been cultivated for food and traditional medicine since ancient times. Pharmacological studies showed that water chestnut exhibits the wide range of biological activities, such as antimicrobial, antioxidative, analgesic, anti-inflammatory, as well as antiulcer. AIM OF THE STUDY: Evaluation of anti-virulence potential and toxicity of T. natans methanol (TnM), acetone (TnA) and ethyl acetate (TnEA) leaf extracts. MATERIALS AND METHODS: The anti-quorum sensing activity of Tn extracts was addressed by measuring their effects on biofilm formation, swarming motility and pyocyanin and elastase production in Pseudomonas aeruginosa. Specific P. aeruginosa biosensors were used to identify which of the signaling pathways were affected. The lethal and developmental toxicity of extracts were addressed in vivo using the zebrafish (Danio rerio) model system. The phenolic composition of T. natans leafs extracts was analyzed by a linear ion trap-OrbiTrap hybrid mass spectrometer (LTQ OrbiTrapMS) and UHPLC system configured with a diode array detector (DAD) hyphenated with the triple quadrupole mass spectrometer. RESULTS: Subinhibitory concentrations of Tn leaf extracts (0.2 MIC) inhibited pyocyanin and elastase production up to 50% and 60%, respectively, and reduced swarming zones, comparing to non-treated P. aeruginosa. TnA inhibited biofilm formation by 15%, TnM showed a stimulatory effect on biofilm formation up to 20%, while TnEA showed no effect. The bioactive concentrations of TnM and TnA were not toxic in the zebrafish model system. Twenty-two phenolic compounds were tentatively identified in TnM, where thirteen of them were identified in T. natans for the first time. Tn extracts, as well as their major components, ellagic and ferulic acids, demonstrated the ability to interfere with P. aeruginosa Las and PQS signaling pathways. CONCLUSIONS: This study demonstrates anti-virulence potential of Tn leaf extracts against medically important pathogen P. aeruginosa and confirms the ethnopharmacological application of this plant against microbial infections.


Assuntos
Lythraceae , Extratos Vegetais/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Percepção de Quorum/efeitos dos fármacos , Animais , Linhagem Celular , Embrião não Mamífero , Humanos , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/análise , Folhas de Planta , Pseudomonas aeruginosa/patogenicidade , Pseudomonas aeruginosa/fisiologia , Virulência/efeitos dos fármacos , Peixe-Zebra
9.
J AOAC Int ; 100(4): 862-870, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28534465

RESUMO

The present work aims to provide a contribution to the overall investigation of European unifloral honeys with regard to authentication according to botanical and geographical origins. The mineral content of 206 monofloral honey samples of five botanical origins from six different regions in Serbia was investigated by inductively coupled plasma optical emission spectrometry. Chemometric techniques were applied for the classification and differentiation of acacia, sunflower, and linden honey according to botanical origin, as well as acacia honey samples according to regional origin. The highest influence on the differentiation of acacia honey samples was the presence of siderophile and chalcophile elements, whereas sunflower and linden honeys were determined by the presence of lithophile elements, indicating their origin from soil. However, due to the different bioaccumulation properties of plants, the presence of elements is not necessarily directly correlated to their presence in soil, which is confirmed by the results of the authentication of geographical origin of acacia honey.


Assuntos
Mel/análise , Minerais/análise , Acacia , Geografia , Helianthus , Análise Espectral , Tilia
10.
11.
J AOAC Int ; 100(4): 852-861, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28527184

RESUMO

In recent years, the botanical and geographical origin of food has become an important topic in the context of food quality and safety, as well as consumer protection, in accordance with international standards. Finding chemical markers, especially phytochemicals, characteristic for some kind of food is the subject of interest of a significant number of researchers in the world. This paper is focused on the use of polyphenols as potential markers for the determination of botanical origin of honey. It includes a review of the polyphenols present in various honey samples and the methods for their separation and identification. Special emphasis in this paper is placed on the identification of honey polyphenols using advanced LC-MS techniques in order to find specific markers of botanical origin of honey. In this regard, this study gives an overview of the literature that describes the use of LC-MS techniques for the isolation and determination of honey polyphenols. This review focuses on the research performed in the past two decades.


Assuntos
Mel/análise , Polifenóis/análise , Cromatografia Líquida , Qualidade dos Alimentos , Espectrometria de Massas
12.
J Pharm Biomed Anal ; 132: 35-45, 2017 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-27693951

RESUMO

Chamomile tea composed of dried flower heads of Matricaria recutita L. (Asteraceae) is one of the most popular single ingredient herbal teas. Tea industries, spice shops or public bazaars are mostly supplied chamomile as a raw material via cultivation or through nature-picking. However, one of the drawbacks of nature-picking is adulteration. This could be either due to false authentication of the plant materials by ingenuous pickers or intentional/unintentional substitution with other flowers resembling to chamomile in appearance during harvesting. Therefore, quality control of raw chamomile materials before marketing should be carefully considered not only by quantification of apigenin 7-O-glucoside (active marker) but also by fingerprinting of chemical composition. This work presents both quantification of apigenin 7-O-glucoside and chemical fingerprinting of commercial chamomile tea products obtained from different food stores and spice shops by a validated HPTLC method. In addition, HPTLC profiles of investigated chamomile tea samples were compared with HPLC method stated in the European Pharmacopoeia and it was found that HPTLC method was superior to HPLC method in the field of adulteration confirmation. Therefore, fingerprint profiles performed on the silica gel 60 NH2 F254s HPTLC plates combined with pattern recognition techniques of these marketed products were comparatively evaluated with wild and cultivar chamomile samples and also chamomile-like species from Asteraceae. Consequently, not chamomile tea bags but crude flowers sold on market were found to be adulterated with other plant materials.


Assuntos
Camomila/química , Cromatografia Líquida de Alta Pressão/métodos , Análise de Alimentos/métodos , Chás de Ervas/análise , Apigenina/química , Asteraceae/química , Flores/química , Géis/química , Processamento de Imagem Assistida por Computador , Matricaria/química , Análise Multivariada , Extratos Vegetais/química , Controle de Qualidade , Dióxido de Silício/química
13.
Talanta ; 162: 72-79, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27837887

RESUMO

Considering the introduction of phytochemical fingerprint analysis, as a method of screening the complex natural products for the presence of most bioactive compounds, use of chemometric classification methods, application of powerful scanning and image capturing and processing devices and algorithms, advancement in development of novel stationary phases as well as various separation modalities, high-performance thin-layer chromatography (HPTLC) fingerprinting is becoming attractive and fruitful field of separation science. Multivariate image analysis is crucial in the light of proper data acquisition. In a current study, different image processing procedures were studied and compared in detail on the example of HPTLC chromatograms of plant resins. In that sense, obtained variables such as gray intensities of pixels along the solvent front, peak area and mean values of peak were used as input data and compared to obtained best classification models. Important steps in image analysis, baseline removal, denoising, target peak alignment and normalization were pointed out. Numerical data set based on mean value of selected bands and intensities of pixels along the solvent front proved to be the most convenient for planar-chromatographic profiling, although required at least the basic knowledge on image processing methodology, and could be proposed for further investigation in HPLTC fingerprinting.


Assuntos
Produtos Biológicos/análise , Cromatografia em Camada Delgada/métodos , Resinas Vegetais/análise , Cromatografia em Camada Delgada/instrumentação , Fenóis/análise , Plantas/química , Plantas/classificação , Análise de Componente Principal , Reprodutibilidade dos Testes , Sérvia , Especificidade da Espécie
14.
Food Chem ; 217: 705-715, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27664689

RESUMO

Spice peppers (Capsicum annuum L.) var. Lemeska and Lakosnicka paprika were investigated to evaluate their polyphenolic and carbohydrate profiles and antioxidant activity. A total of forty-nine polyphenolics were identified using ultrahigh-performance liquid chromatography (UHPLC) coupled to LTQ OrbiTrap mass analyzer. Twenty-five of them were quantified using available standards, while the other compounds were confirmed by exact mass search of their deprotonated molecule [M-H](-) and its MS(4) fragmentation. Thirteen carbohydrates were quantified using high-performance anion exchange chromatography (HPAEC) with pulsed amperometric detection (PAD). Radical scavenging activity (RSA) ranged from 17.32 to 48.34mmol TE (Trolox equivalent)/kg DW (dry weight) and total phenolics content (TPC) was ranged between 7.03 and 14.92g GAE (gallic acid equivalents)/kg DW. To our best knowledge, five polyphenolic compounds were for the first time tentatively identified in paprika: 5-O-p-coumaroylquinic acid, luteolin 7-O-(2″-O-pentosyl-4″-O-hexosyl)hexoside, quercetin 3-O-(2″-O-hexosyl)rhamnoside, isorhamnetin 3-O-[6″-O-(5-hydroxyferuloyl)hexoside]-7-O-rhamnoside, and luteolin 7-O-[2″-O-(5'″-O-sinapoyl)pentosyl-6″-O-malonyl]hexoside.


Assuntos
Capsicum/química , Carboidratos/análise , Polifenóis/análise , Especiarias/análise , Capsicum/classificação , Cromatografia Líquida de Alta Pressão/métodos , Geografia , Luteolina/análise , Extratos Vegetais/análise , Quercetina/análogos & derivados , Sérvia
15.
J Chromatogr A ; 1458: 136-44, 2016 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-27378251

RESUMO

Soil-water partition coefficient normalized to the organic carbon content (KOC) is one of the crucial properties influencing the fate of organic compounds in the environment. Chromatographic methods are well established alternative for direct sorption techniques used for KOC determination. The present work proposes reversed-phase thin-layer chromatography (RP-TLC) as a simpler, yet equally accurate method as officially recommended HPLC technique. Several TLC systems were studied including octadecyl-(RP18) and cyano-(CN) modified silica layers in combination with methanol-water and acetonitrile-water mixtures as mobile phases. In total 50 compounds of different molecular shape, size, and various ability to establish specific interactions were selected (phenols, beznodiazepines, triazine herbicides, and polyaromatic hydrocarbons). Calibration set of 29 compounds with known logKOC values determined by sorption experiments was used to build simple univariate calibrations, Principal Component Regression (PCR) and Partial Least Squares (PLS) models between logKOC and TLC retention parameters. Models exhibit good statistical performance, indicating that CN-layers contribute better to logKOC modeling than RP18-silica. The most promising TLC methods, officially recommended HPLC method, and four in silico estimation approaches have been compared by non-parametric Sum of Ranking Differences approach (SRD). The best estimations of logKOC values were achieved by simple univariate calibration of TLC retention data involving CN-silica layers and moderate content of methanol (40-50%v/v). They were ranked far well compared to the officially recommended HPLC method which was ranked in the middle. The worst estimates have been obtained from in silico computations based on octanol-water partition coefficient. Linear Solvation Energy Relationship study revealed that increased polarity of CN-layers over RP18 in combination with methanol-water mixtures is the key to better modeling of logKOC through significant diminishing of dipolar and proton accepting influence of the mobile phase as well as enhancing molar refractivity in excess of the chromatographic systems.


Assuntos
Carbono/análise , Cromatografia de Fase Reversa/métodos , Cromatografia em Camada Delgada/métodos , Compostos Orgânicos/análise , Solo/química , Água/química , Acetonitrilos/química , Calibragem , Carbono/química , Cromatografia Líquida de Alta Pressão , Modelos Lineares , Metanol/química , Octanóis/química , Compostos Orgânicos/química
16.
PLoS One ; 11(6): e0157097, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27272728

RESUMO

New information has come to light about the biological activity of propolis and the quality of natural products which requires a rapid and reliable assessment method such as High Performance Thin-Layer Chromatography (HPTLC) fingerprinting. This study investigates chromatographic and chemometric approaches for determining the antimicrobial activity of propolis of Serbian origin against various bacterial species. A linear multivariate calibration technique, using Partial Least Squares, was used to extract the relevant information from the chromatographic fingerprints, i.e. to indicate peaks which represent phenolic compounds that are potentially responsible for the antimicrobial capacity of the samples. In addition, direct bioautography was performed to localize the antibacterial activity on chromatograms. The biological activity of the propolis samples against various bacterial species was determined by a minimum inhibitory concentration assay, confirming their affiliation with the European poplar type of propolis and revealing the existence of two types (blue and orange) according to botanical origin. The strongest antibacterial activity was exhibited by sample 26 against Staphylococcus aureus, with a MIC value of 0.5 mg/mL, and Listeria monocytogenes, with a MIC as low as 0.1 mg/mL, which was also the lowest effective concentration observed in our study. Generally, the orange type of propolis shows higher antimicrobial activity compared to the blue type. PLS modelling was performed on the HPTLC data set and the resulting models might qualitatively indicate compounds that play an important role in the activity exhibited by the propolis samples. The most relevant peaks influencing the antimicrobial activity of propolis against all bacterial strains were phenolic compounds at RF values of 0.37, 0.40, 0.45, 0.51, 0.60 and 0.70. The knowledge gained through this study could be important for attributing the antimicrobial activity of propolis to specific chemical compounds, as well as the verification of HPTLC fingerprinting as a reliable method for the identification of compounds that are potentially responsible for antimicrobial activity. This is the first report on the activity of Serbian propolis as determined by several combined methods, including the modelling of antimicrobial activity by HPTLC fingerprinting.


Assuntos
Antibacterianos/farmacologia , Fenóis/química , Própole/farmacologia , Antibacterianos/química , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia em Camada Delgada/métodos , Listeria monocytogenes/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Própole/química , Staphylococcus aureus/efeitos dos fármacos
17.
J Chromatogr Sci ; 54(7): 1077-83, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26931733

RESUMO

Propolis is a "natural" remedy with prominent biological activity, which is used as dietary supplement. In the absence of clinical studies that would substantiate these claims, information on the biological activity of propolis is valuable. This study comprises chromatographic, image processing and chemometric approach for phenolic profiling of Serbian, Croatian and Slovenian propolis test solutions. Modern thin-layer chromatography equipment in combination with software for image processing was applied for fingerprinting and data acquisition, whereas the principal component analysis was used as pattern recognition method. Characterization of phenolic profile was performed along with the determination of the botanical and geographical origin of propolis. High-performance thin-layer chromatograms reveal that Central and Southeastern European propolis samples are rich in flavonoids. In addition, phenolic compounds proved to be suitable markers for the determination of European propolis authenticity.


Assuntos
Cromatografia em Camada Delgada/normas , Flavonoides/isolamento & purificação , Processamento de Imagem Assistida por Computador/estatística & dados numéricos , Fenóis/isolamento & purificação , Própole/química , Animais , Abelhas/fisiologia , Croácia , Humanos , Populus , Análise de Componente Principal , Resinas Vegetais/química , Sérvia , Eslovênia , Ceras/química
18.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1012-1013: 144-52, 2016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-26827282

RESUMO

The chromatographic behaviour of series of 4-amino-7-chloroquinoline (4,7-ACQ) based compounds was studied by reversed-phase thin-layer chromatography (RPTLC) with binary mobile phases containing water and the organic modifiers, DMSO or acetone. The lipophilicity of the studied compounds was determined by extrapolation of retention parameters RM to pure water content in mobile phase. In order to obtain some basic insight into the chromatographic behaviour and structural features of investigated compounds, PCA was performed on both chromatographic data (RM values) and calculated 2D and 3D structural descriptors. Both QSRR and QSAR models were built by means of the partial least squares (PLS) statistical method. It was found that descriptors which encode hydrophobic (dispersive) interactions have positive influence on retention, while influence of descriptors encoding polar interactions was negative. According to the obtained PLS model for inhibition of botulinum neurotoxin serotype A light chain, hydrophobic interactions influence positively on the mechanism of action of the investigated 4,7-ACQ, while polar interactions are less favoured. Contrary, the results of PLS modelling of activity against Plasmodium falciparum strains (W2, D6 and TM91C235) indicate that higher polarity of 4,7-ACQ contribute to their higher antimalarial activity.


Assuntos
Quinolinas/análise , Quinolinas/química , Cromatografia em Camada Delgada/métodos , Interações Hidrofóbicas e Hidrofílicas , Relação Quantitativa Estrutura-Atividade
19.
J Sci Food Agric ; 96(4): 1241-51, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25867015

RESUMO

BACKGROUND: Oblacinska sour cherry, an autochthonous cultivar, is the most planted cultivar in Serbian commercial orchards. Owing to its long cultivation under different agro-ecological conditions, it is a mixture of different clones. To obtain comprehensive information on Oblacinska sour cherry fruit, the total carbohydrate composition, total phenolic content, total anthocyanin content, antioxidant activity and polyphenolic profiles of 39 clones were investigated. RESULTS: Fructose was found to be the dominant sugar, followed by glucose, sorbitol and sucrose. Rutin and chlorogenic acid were the most abundant polyphenols. Some clones contained pinobanksin, hesperetin and galangin, which, to best knowledge, is the first time these compounds have been reported in sour cherry fruit. CONCLUSION: The data obtained showed huge variation within the germplasm studied, confirming the fact that Oblacinska sour cherry is not a cultivar but a population.


Assuntos
Frutas/química , Promoção da Saúde , Prunus avium , Paladar , Antocianinas/análise , Antioxidantes/análise , Carboidratos/análise , Ácido Clorogênico/análise , Frutose/análise , Fenóis/análise , Extratos Vegetais/química , Polifenóis/análise , Rutina/análise , Sérvia
20.
Plant Foods Hum Nutr ; 70(4): 433-40, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26497505

RESUMO

Large amounts of fruit seeds, especially peach, are discarded annually in juice or conserve producing industries which is a potential waste of valuable resource and serious disposal problem. Regarding the fact that peach seeds can be obtained as a byproduct from processing companies their exploitation should be greater and, consequently more information of cultivars' kernels and their composition is required. A total of 25 samples of kernels from various peach germplasm (including commercial cultivars, perspective hybrids and vineyard peach accessions) differing in origin and ripening time were characterized by evaluation of their sugar composition. Twenty characteristic carbohydrates and sugar alcohols were determined and quantified using high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC/PAD). Sucrose, glucose and fructose are the most important sugars in peach kernels similar to other representatives of the Rosaceae family. Also, high amounts of sugars in seeds of promising hybrids implies that through conventional breeding programs peach kernels with high sugar content can be obtained. In addition, by the means of several pattern recognition methods the variables that discriminate peach kernels arising from diverse germplasm and different stage of maturity were identified and successful models for further prediction were developed. Sugars such as ribose, trehalose, arabinose, galactitol, fructose, maltose, sorbitol, sucrose, iso-maltotriose were marked as most important for such discrimination.


Assuntos
Carboidratos/análise , Prunus persica , Sementes/química , Cromatografia Líquida de Alta Pressão , Manipulação de Alimentos , Frutose/análise , Frutas/química , Glucose/análise , Prunus persica/química , Prunus persica/classificação , Prunus persica/crescimento & desenvolvimento , Sacarose/análise , Edulcorantes , Resíduos
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