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1.
RSC Adv ; 13(46): 32714-32721, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37942450

RESUMO

5-Hydroxymethylfurfural (HMF), a Maillard reaction product, can be formed when honey is subjected to heat treatment or a long storage time, becoming volatile and toxic depending on its concentration. The fact that, until today, there is no literature data on the extraction of 5-hydroxymethylfurfural (HMF) from honey using ionic liquids directed the investigation of the influence of biodegradable cholinium ionic liquids on the formation of aqueous biphasic systems and the application of these systems for the extraction of HMF from honey. The influence of anions of synthesised ionic liquids on the construction of biphasic systems in which an inorganic salt was used as a salting agent was investigated. Then, the extraction of HMF in these systems was examined, and the mechanisms of HMF extraction using ionic liquids were explained using computer simulations. Examining the effect of cholinium ionic liquids (choline chloride ([Ch][Cl]), cholinium nicotinate ([Ch][Nic]), cholinium propionate ([Ch][Prop]), and cholinium butyrate ([Ch][But])) on the formation of aqueous biphasic systems by comparing the phase diagrams, it was concluded that the ability of ionic liquids to form an aqueous biphasic system with tripotassium phosphate (K3PO4) decreases in the following order: [Ch][But] ≈ [Ch][Prop] > [Ch][Nic] > [Ch][Cl]. By applying all tested aqueous biphasic systems for the extraction of HMF from honey, an extraction efficiency of more than 89% was achieved. Complete extraction was achieved using the extraction system with [Ch][But], while the weakest ability to extract HMF was exhibited by the system with [Ch][Cl]. The mechanisms of HMF extraction using ionic liquids are explained on the basis of the optimised structures of the ionic liquid systems with HMF, together with the visualisation of non-covalent interactions, and on the basis of the calculated binding energies ΔGbin, which can be used as a good predictor of the extraction potential of newly synthesised ionic liquids.

2.
Antioxidants (Basel) ; 11(6)2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35740017

RESUMO

This paper presents the physicochemical characteristics and antioxidative, antibacterial and antiproliferative effects of nineteen samples of different honey types (acacia, linden, heather, sunflower, phacelia, basil, anise, sage, chestnut, hawthorn, lavender and meadow) collected from different locations in the Western Balkans (Republic of Serbia, Kosovo, Bosnia and Herzegovina, and Northern Macedonia). Physicochemical parameters (moisture, pH, electrical conductivity, free acidity, and hydroxymethylfurfural [HMF]) were analysed. Based on the obtained results, all tested honey samples were in agreement with EU regulation. The antioxidant potential of honey samples was assessed by determination of total phenolic content (TPC) and evaluation of scavenging activity towards diphenilpicrylhydrazyl radicals (DPPH·). The highest phenolic content was found in basil honey (101 ± 2.72 mg GAE/100 g), while the lowest was registered in rapeseed honey (11.5 ± 0.70 mg GAE/100 g). Heather, anise, phacelia, sage, chestnut and lavender honey samples were also rich in TP, containing 80−100 mg GAE/100 g. DPPH scavenging activity varied among the samples being the highest for lavender honey (IC50 = 88.2 ± 2.11 mg/mL) and the lowest for rapeseed honey (IC50 = 646 ± 8.72 mg/mL). Antibacterial activity was estimated in vitro using agar diffusion tests and measuring minimal inhibitory concentration (MIC). Among investigated bacterial strains following resistant potencies were determined: Escherichia coli > Escherichia coli ATCC 8739 > Enterococcus faecalis > Proteus mirabilis > Staphylococcus aureus > Staphylococcus epidermidis. The linden honey from Fruska Gora (MIC values of 3.12% and 6.25% against Staphylococcus aureus and Staphylococcus epidermidis, respectively) and phacelia honey (MIC values of 6.25% and 3.12% against S.Staphylococcus aureus and Staphylococcus epidermidis, respectively) showed the strongest antibacterial activity. Antiproliferative activity was evaluated using the colorimetric sulforhodamine B (SRB) assay. The highest antiproliferative activity was obtained from linden honey sample 1 (IC50MCF7 = 7.46 ± 1.18 mg/mL and IC50HeLa =12.4 ± 2.00 mg/mL) and meadow sample 2 (IC50MCF7 = 12.0 ± 0.57 mg/mL, IC50HeLa = 16.9 ± 1.54 mg/mL and IC50HT−29 = 23.7 ± 1.33 mg/mL) towards breast (MCF7), cervix (HeLa) and colon (HT-29) cancer cells. Active components other than sugars contributed to cell growth activity.

3.
Foods ; 10(11)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34828911

RESUMO

This study was focused on the creation of high-protein bars formulated using whey protein isolate (24%) and soy protein isolate (6%) as the sources of proteins; oat flakes and inulin, both abundant in dietary fibres, and creatine monohydrate and other minor ingredients (vitamin and mineral mixture, potassium sorbate) to achieve the requirements for a meal replacement formula for physically active people. The nutritional profile of the high-protein bar was examined (energy 1215 kJ/288 kcal; protein 34.1 ± 0.20 g, fat 6.01 ± 0.13 g of which was saturated 3.12 ± 0.08 g, fibre 3.10 ± 0.17 g carbohydrate 23.0 ± 0.16 g of which sugars 1.50 ± 0.19 g and starch 21.5 ± 0.11 g in 100 g), and sensory properties with instrumental parameters (texture and colour) were determined and compared with bars commercially available on the market. The created high-protein bar was sensorily acceptable in comparison to other commercially available bars. The dietary intervention study was conducted on elite athletes (professional handball players) to evaluate effects of created versus control bar consumption on their metabolic parameters. The baseline characteristics (mean age, body mass index (BMI), fat mass, muscle mass, lean mass and fat percentage) of the athletes (8) were determined at the start of the study. The cross-over intervention study was organized in two successive phases (5 days each) with a seven-day long washout period between phases. Bars were consumed after the afternoon training unit. Blood samples were collected at the start and the end of the intervention study to analyse the metabolic profiles of the athletes. Serum levels of high-density cholesterol (HDL), low-density cholesterol (LDL) and total cholesterol (HOL), glucose, triacylglycerides (TAG), total and direct bilirubin, creatine kinase (CK), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) were measured. The results showed that bar consumption significantly decreased serum aspartate transaminase (AST) and lactate dehydrogenase (LDH) and increased total and direct bilirubin levels, suggesting lower exercise-induced muscle damage and increased antioxidative response, respectively. Therefore, it can be concluded that the consumption of the created high-protein bar was able to improve physiological adaptation after training.

4.
Ultrason Sonochem ; 79: 105761, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34601448

RESUMO

Cereal brans are by-products of the milling of cereal grains, which are mainly used as low value ingredients in animal feed. Wheat and oat bran is a rich source of bioactives and phytochemicals, especially phenolic compounds. Within this study, the application of ultrasound (US) technology to assist the extraction of phenolics from oat and wheat bran was investigated (20-45 kHz). Peleg's mathematical model was used to study the kinetics of ultrasound-assisted extraction (UAE) and subsequent stirring of total phenolic compounds (TPC). The surface morphology of cereal brans after extraction was studied using SEM analysis. The excellent agreement was determined between the values of TPC calculated from Peleg's mathematical model and actual experimental results. The constant that represents a time required for the initial phenolic concentration to be extracted to one-half of its initial value has been introduced (K1/2). It was shown that the TPC extraction kinetics was dependent only on K1/2 enabling fast kinetics fitting and comparison between extraction rates. Moreover, different values of K1/2 constant could indicate the differences in brans composition and consequently different influence of US pretreatment on these samples.


Assuntos
Grão Comestível , Fenóis , Animais , Antioxidantes/análise , Fibras na Dieta/análise , Grão Comestível/química , Cinética , Ondas Ultrassônicas
5.
RSC Adv ; 11(20): 12434-12441, 2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35423727

RESUMO

One hundred honey samples of different floral origin (acacia, sunflower, meadow, and forest) collected from nine European countries (Serbia, Albania, Croatia, Montenegro, Romania, Bulgaria, Bosnia and Herzegovina, North Macedonia and Hungary) were analysed for various physicochemical, sensory, antioxidant and antibacterial parameters. The relative antioxidant capacity index and relative antibacterial index were calculated, integrated and expressed as a new property - Power of Honey, intended to be used to predict the health potential of a honey based on its antioxidant and antibacterial activities. Free acidity and colour coordinates L* and a* were chosen for building an artificial neural network model for the prediction of honey health potential. These were chosen based on the obtained correlations between the investigated parameters and in light of the simplicity of the analysis. This model successfully predicted the Power of Honey with a gained coefficient of determination of 0.856. Forest honey samples exhibited the highest Power of Honey. This novel approach should make it possible for honey producers to predict the honey health potential of a particular honey based on a quick and simple analysis.

6.
J Int Soc Sports Nutr ; 16(1): 27, 2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31272457

RESUMO

BACKGROUND: The aim of this international study was to investigate the prevalence of the use of sports supplements among young athletes, as well as their knowledge and attitudes towards sports supplementation. METHODS: Organized survey study testing the level of knowledge, attitudes, beliefs and practices concerning the use of sports supplements was administered to 348 athletes, 15-18 year olds from 4 countries competing in 18 sports at the international level. RESULTS: The prevalence rate of the intake of sports supplements was 82.2%, with the protein supplements being predominant (54.5%). Coaches were identified as the primary source of information regarding supplementation (41.4%). The enhancement of athletic performance (35.4%) was the major motivation for the supplements intake. The majority of athletes (72.1%) were aware of associated health risks. The young athletes possess varying levels of knowledge regarding their own supplementation. The obtained data about the level of knowledge were statistically analyzed using the correspondence analysis. Less than 40% of athletes had the knowledge about the proper and intended use of protein, creatine, amino acids, beta alanine and glutamine, while they had greater understanding about vitamins and minerals, sports drinks and caffeine. The athletes in developed countries had greater access and utilization of professional resources such as dieticians. Young athletes are still unfamiliar with WADA regulations (55.5%), and the misuse of sports supplements represents an ethical dilemma for some. CONCLUSION: These findings indicate the necessity of a comprehensive education of all team members about sports supplements and careful supervision of the athletic development of young athletes.


Assuntos
Atletas , Suplementos Nutricionais , Conhecimentos, Atitudes e Prática em Saúde , Adolescente , Desempenho Atlético , Croácia , Feminino , Alemanha , Humanos , Japão , Masculino , Motivação , Prevalência , Sérvia , Fenômenos Fisiológicos da Nutrição Esportiva , Inquéritos e Questionários
7.
J Texture Stud ; 50(2): 124-130, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30345519

RESUMO

Raspberry and blueberry pomace, by-products from fruit juice industry, were dehydrated to obtain fruit fiber concentrates and valorized as ingredients in gluten-free (GF) cookies formulation. The aim was to evaluate the effect of substituting 30% (w/w) of GF flour mixture with different ratios of blueberry/raspberry fiber concentrates (0/30, 15/15, and 30/0) on rheological properties of cookie dough and cookie baking quality. Generally, the incorporation of the fiber concentrates increased the elastic and the viscous moduli thus producing harder doughs and consequently firmer cookies in comparison to the control. Although having similar total, soluble and insoluble fiber content, blueberry fiber concentrates were characterized with higher water absorption capacity and consequently yielded cookies with more rigid dough structure, higher water loss during baking, lower cookie thickness, higher spread ratio, more dense inner structure, and increased cookie hardness than those containing raspberry fiber concentrates. Enrichment of GF cookies with raspberry and blueberry fiber concentrates resulted in products with dietary fiber content higher than 6 g per 100 g, thus making them candidates for bearing "high fiber" nutrition claim. PRACTICAL APPLICATIONS: Currently available GF bakery products mostly lack dietary fibers (DFs) and other important nutrients, because they are usually manufactured from refined flour and/or starches. As the products with long shelf-life, very popular in daily diet of almost all consumer profiles, cookies could represent good matrices for the addition of functional ingredients, such as DFs. In this paper, GF cookies were enriched with the fiber concentrates recovered from blueberry and raspberry pomace. Application of these fiber sources enabled recycling of fruit processing industry by-products into novel, "high fiber" GF product with improved nutritive profile.


Assuntos
Mirtilos Azuis (Planta)/química , Pão/análise , Dieta Livre de Glúten , Fibras na Dieta/análise , Reologia , Rubus/química , Culinária/métodos , Manipulação de Alimentos , Dureza , Modelos Químicos , Viscosidade
8.
Food Chem ; 276: 15-21, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30409578

RESUMO

Forty-five honey samples of three honey types - two monofloral (acacia and sunflower) and one polyfloral (meadow) were collected from the Autonomous Province of Vojvodina (Republic of Serbia) and analysed for their physicochemical parameters (moisture, acidity, pH, ash, electrical conductivity, glucose, fructose, hydroxymethylfurfural (HMF), CIE L∗a∗b∗ colour and mineral content). All tested physicochemical parameters were in agreement with the EU regulation except for moisture (4 samples) and HMF content (1 sample). Principal component analysis (PCA) was used for assessing the effects of three honey types on all investigated physicochemical parameters. According to PCA, acacia honey samples can be clearly isolated and form a cluster, while, regarding other honey types, PCA can offer the possibility to distinguish sunflower and meadow honey samples regarding examined physicochemical parameters and mineral content.


Assuntos
Fenômenos Químicos , Mel/análise , Minerais/análise , Carboidratos/análise , Condutividade Elétrica , Concentração de Íons de Hidrogênio , Sérvia
9.
BMC Complement Altern Med ; 18(1): 300, 2018 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-30419892

RESUMO

BACKGROUND: The interest towards botanicals and plant extracts has strongly risen due to their numerous biological effects and ability to counteract chronic diseases development. Among these effects, chemoprevention which represents the possibility to counteract the cancerogenetic process is one of the most studied. The extracts of mushroom Meripilus giganteus (MG) (Phylum of Basidiomycota) showed to exert antimicrobic, antioxidant and antiproliferative effects. Therefore, since its effect in leukemic cell lines has not been previously evaluated, we studied its potential chemopreventive effect in Jurkat and HL-60 cell lines. METHODS: MG ethanolic extract was characterized for its antioxidant activity and scavenging effect against different radical species. Moreover, its phenolic profile was evaluated by HPLC-MS-MS analyses. Flow cytometry (FCM) analyses of Jurkat and HL-60 cells treated with MG extract (0-750 µg/mL) for 24-72 h- allowed to evaluate its cytotoxicity, pro-apoptotic and anti-proliferative effect. To better characterize MG pro-apoptotic mechanism ROS intracellular level and the gene expression level of FAS, BAX and BCL2 were also evaluated. Moreover, to assess MG extract selectivity towards cancer cells, its cytotoxicity was also evaluated in human peripheral blood lymphocytes (PBL). RESULTS: MG extract induced apoptosis in Jurkat and HL-60 cells in a dose- and time- dependent manner by increasing BAX/BCL2 ratio, reducing ROS intracellular level and inducing FAS gene expression level. In fact, reduced ROS level is known to be related to the activation of apoptosis in leukemic cells by the involvement of death receptors. MG extract also induced cell-cycle arrest in HL-60 cells. Moreover, IC50 at 24 h treatment resulted 2 times higher in PBL than in leukemic cell lines. CONCLUSIONS: Our data suggest that MG extract might be considered a promising and partially selective chemopreventive agent since it is able to modulate different mechanisms in transformed cells at concentrations lower than in non-transformed ones.


Assuntos
Apoptose/efeitos dos fármacos , Produtos Biológicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Polyporales/química , Antineoplásicos/farmacologia , Etanol , Células HL-60 , Humanos , Células Jurkat , Leucemia
10.
Anal Chim Acta ; 1028: 96-103, 2018 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-29884358

RESUMO

The biosynthesis of creatine (Cr) is closely related to the bioavailability of guanidinoacetate (GAA). The lack of one or the other may compromise their role in the energy transport and cell signaling. A reliable estimate of their levels in biological samples is imperative since they are important markers of many metabolic disorders. Therefore, a new LC-MS/MS method for simultaneous determination and quantification of GAA and Cr by multiple reaction monitoring (MRM) mode was developed based on the hydrophilic interaction chromatography (HILIC) and response surface methodology (RSM) for the optimization of chromatographic parameters. The optimized parameters ensured good separation of these similar, very polar molecules (chromatographic resolution > 1.5) without prior derivatization step in a short analysis run (6 min). The developed method was validated to ensure accurate (R, 75.1-101.6%), precise (RSD < 20%) and low quantification (LOQ of 0.025 µg mL-1 for GAA and 0.006 µg mL-1 for Cr) of the tested analytes and the use of matrix-matched calibration eliminated variable effects of complex matrices such as human plasma and urine. Therefore, this method can be implemented in medical laboratories as a tool for the diagnostics of creatine deficiencies and monitoring of guanidinoacetate and creatine supplementation regimes in biological samples.


Assuntos
Cromatografia Líquida/métodos , Creatina/análise , Glicina/análogos & derivados , Interações Hidrofóbicas e Hidrofílicas , Espectrometria de Massas em Tandem/métodos , Calibragem , Creatina/sangue , Creatina/urina , Glicina/análise , Glicina/sangue , Glicina/urina , Humanos , Limite de Detecção , Reprodutibilidade dos Testes , Fatores de Tempo
11.
Molecules ; 22(8)2017 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-28788076

RESUMO

The aim of the study was to evaluate antioxidant activity and total phenolic content of juice from three different types of fruits: elderberry (Sambucusnigra), lingonberry (Vacciniumvitis-idaea) and cornelian cherry (Cornusmas), and their action against adhesion of bacterial strains of Asaialannensis and Asaiabogorensis isolated from spoiled soft drinks. The antioxidant profiles were determined by total antioxidant capacity (2,2-diphenyl-1-picrylhydrazyl, DPPH), and ferric-reducing antioxidant power (FRAP). Additionally, total polyphenol content (TPC) was investigated. Chemical compositions of juices were tested using the chromatographic techniques: high-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS). Adhesion properties of Asaia spp. cells to various abiotic materials were evaluated by luminometry, plate count and fluorescence microscopy. Antioxidant activity of fruit juices expressed as inhibitory concentration (IC50) ranged from 0.042 ± 0.001 (cornelian cherry) to 0.021 ± 0.001 g/mL (elderberry). TPC ranged from 8.02 ± 0.027 (elderberry) to 2.33 ± 0.013 mg/mL (cornelian cherry). Cyanidin-3-sambubioside-5-glucoside, cyanidin-3-glucoside, and cyanidin-3-sambubioside were detected as the major anthocyanins and caffeic, cinnamic, gallic, protocatechuic, and p-coumaric acids as the major phenolic acids. A significant linear correlation was noted between TPC and antioxidant capacity. In the presence of fruit juices a significant decrease of bacterial adhesion from 74% (elderberry) to 67% (lingonberry) was observed. The high phenolic content indicated that these compounds may contribute to the reduction of Asaia spp. adhesion.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Bebidas/microbiologia , Carboidratos/análise , Cromatografia Líquida , Frutas/química , Sucos de Frutas e Vegetais/análise , Espectrometria de Massas , Polifenóis/química , Polifenóis/farmacologia , Análise de Componente Principal
12.
Phytother Res ; 30(5): 855-60, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26929014

RESUMO

The aim of the present work was to examine if hydrogen peroxide treatment of sugar beet fibre that aimed at improving its physicochemical properties would impair its antioxidant potential. Three different sugar beet fibres were obtained from sugar beet - non-treated fibre (NTF) from sugar beet cossettes extracted with sulphurous acid, treated fibre (TF) from NTF treated with hydrogen peroxide in alkaline solution and commercially available Fibrex(®) . The antioxidant activity of extractable and non-extractable fibre fractions in ethanol/water mixture (80:20, v/v) of three fibre samples was estimated. Non-extractable fractions obtained after alkaline treatment of investigated fibres were much higher in phenolic compounds and possessed higher antioxidant potential than extractable fractions. Ferulic acid was proven to be the dominant phenolic acid. Regarding both extractable and non-extractable fractions, Fibrex(®) had the highest antioxidant activity in chemical tests, while NTF was superior in comparison with TF. Based on the results of Caco-2 cells-based test, all non-extractable fractions possessed potential for reactive oxygen species inhibition. Regarding the extractable fractions, only the TF manifested this effect.Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Beta vulgaris/química , Fibras na Dieta/análise , Peróxido de Hidrogênio/química , Antioxidantes , Humanos
13.
Food Technol Biotechnol ; 53(1): 38-47, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27904330

RESUMO

Light buckwheat flour was used to substitute rice flour at the level of 10, 20 and 30% to produce gluten-free cookies. The substitution of gluten-free cookie formulation with light buckwheat flour contributed to the significantly higher mineral content, especially magnesium, potassium, iron and copper, in comparison with the control rice cookies (p<0.05). Gluten-free cookies made with rice flour and buckwheat flour exhibited significantly higher total phenolic and rutin content, scavenging activity against 1,1-diphenyl-2-picrylhydrazyl radicals (DPPH•), antioxidant activity and reducing power than the control cookies (p<0.05). Comparing all evaluated sensory properties, cookies containing 20% of light buckwheat flour had the most acceptable sensory properties. The obtained results of principal component analysis showed that the cookies with 20 and 30% buckwheat flour had better antioxidant and sensory properties in comparison with other two cookie samples.

14.
J Agric Food Chem ; 62(51): 12436-42, 2014 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-25426777

RESUMO

Valorization of hemp seed meal, a byproduct of hemp oil processing, was performed by measuring the distribution of nutritional and antinutritional compounds in different hemp seed meal fractions. According to chemical composition, two cotyledon-containing fractions (>180 and <180 µm) were significantly richer in protein (p < 0.05) (41.2% ± 0.04% and 44.4% ± 0.02%, respectively), lipid (15.1% ± 0.02% and 18.6% ± 0.04%, respectively), and sugar content (4.96% ± 0.11% and 3.46% ± 0.08%, respectively) in comparison to the hull-containing fractions (>350 and >250 µm), which were significantly richer in crude fiber content (29.5% ± 0.04% and 21.3% ± 0.03%, respectively). The free radical scavenging capacity (IC50) of fraction extracts increased (p < 0.05) with increasing mean particle size (from 17.18 ± 0.59 to 5.29 ± 0.30 mg/mL). Cannabisin B and N-trans-caffeoyltyramine were the most abundant phenolic compounds in the hull fractions (from 267 ± 15.9 to 287 ± 23.1 mg/kg), while cotyledon fractions had higher content of catechin (from 313 ± 12.4 to 744 ± 22.2 mg/kg) and p-hydroxybenzoic acid (from 124 ± 6.47 to 129 ± 8.56 mg/kg (P < 0.05). Well-balanced ω-6 to ω-3 fatty acid ratio (3:1) was determined in all fractions. Antinutrients (trypsin inhibitors, phytic acid, glucosinolates, and condensed tannins) were mostly located in the cotyledon fractions. These findings indicate that the separation of hemp seed meal into different fractions could be used to concentrate valuable target compounds and consequently facilitate their recovery.


Assuntos
Cannabis/química , Extratos Vegetais/química , Óleos de Plantas/química , Resíduos/análise , Cannabis/embriologia , Carboidratos/química , Cotilédone/química , Sequestradores de Radicais Livres/química , Lipídeos/química , Proteínas de Plantas/química , Sementes/química , Sementes/embriologia , Inibidores da Tripsina/química
15.
Talanta ; 111: 125-33, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23622535

RESUMO

The objective of this study was to develop analytical method based on optimized dispersive liquid-liquid microextraction (DLLME) as a pretreatment procedure combined with reversed phase liquid chromatographic separation on C18 column and isocratic elution for simultaneous MS/MS determination of selected neonicotinoid insecticides in honey. The LC-MS/MS parameters were optimized to unequivocally provide good chromatographic separation, low detection (LOD, 0.5-1.0 µg kg(-1)) and quantification (LOQ, 1.5-2.5 µg kg(-1)) limits for acetamiprid, clothianidin, thiamethoxam, imidacloprid, dinotefuran, thiacloprid and nitenpyram in honey samples. Using different types (chloroform, dichloromethane) and volumes of extraction (0.5-3.0 mL) and dispersive (acetonitrile; 0.0-1.0 mL) solvent and by mathematical modeling it was possible to establish the optimal sample preparation procedure. Matrix-matched calibration and blank honey sample spiked in the concentration range of LOQ-100.0 µg kg(-1) were used to compensate the matrix effect and to fulfill the requirements of SANCO/12495/2011 for the accuracy (R 74.3-113.9%) and precision (expressed in terms of repeatability (RSD 2.74-11.8%) and within-laboratory reproducibility (RSDs 6.64-16.2%)) of the proposed method. The rapid (retention times 1.5-9.9 min), sensitive and low solvent consumption procedure described in this work provides reliable, simultaneous, and quantitative method applicable for the routine laboratory analysis of seven neonicotinoid residues in real honey samples.


Assuntos
Anabasina/análise , Cromatografia Líquida/métodos , Mel/análise , Inseticidas/análise , Microextração em Fase Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Anabasina/química , Guanidinas/análise , Guanidinas/química , Imidazóis/análise , Imidazóis/química , Inseticidas/química , Estrutura Molecular , Neonicotinoides , Nitrocompostos/análise , Nitrocompostos/química , Oxazinas/análise , Oxazinas/química , Piridinas/análise , Piridinas/química , Reprodutibilidade dos Testes , Tiametoxam , Tiazinas/análise , Tiazinas/química , Tiazóis/análise , Tiazóis/química
16.
J Food Sci ; 77(9): C954-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22888949

RESUMO

UNLABELLED: Buckwheat (Fagopyrum esculentum Moench) is an alternative crop belonging to the Polygonaceae family. In comparison to antioxidant activity of frequently used cereals, buckwheat has been reported to possess higher antioxidant activity (AOA), mainly due to high rutin content. The objective of this work was to determine the main antioxidant compounds and AOA of buckwheat grain fractions (whole grain, hull, and groat). Buckwheat grain fractions were extracted with ethanol/water (80/20, v/v), followed by determination of total phenolic and flavonoid content. Quantification of phenolic compounds and tocopherols was performed by high-performance liquid chromatography (HPLC). The AOA was estimated by 2 direct electron spin resonance (ESR) and 4 indirect (spectrophotometric) tests. Significantly higher contents of total phenolics and total flavonoids were found in buckwheat hull than in whole grain and groat. Protocatechuic, syringic, and sinapic acid, rutin, and quercetin were found in all tested fractions, whereas vanilic acid was found in whole grain and hull. The content of total tocopherols in investigated samples ranged from 23.3 mmol/g for hull to 61.8 mmol/g for groat. Hull was superior in scavenging activity on 1,1-diphenyl-2-picrylhydrazyl (DPPH(•)), hydroxyl ((•)OH), and superoxide anion (O(2)(•-)) radicals, reducing activity, AOA by ß-carotene bleaching method, and chelating activity on Fe(2+) as evidenced by its lower IC(50) value. Obtained results can broaden the utilization of buckwheat, especially a share of hull in whole grain flour production. PRACTICAL APPLICATION: Obtained results suggest possibility to supplement the whole grain buckwheat flour with hull, which leads toward better usage of by-products in buckwheat production, and enhancement of antioxidant potential of the final product.


Assuntos
Antioxidantes/análise , Fagopyrum/química , Sementes/química , Compostos de Bifenilo/análise , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Farinha/análise , Fenóis/análise , Picratos/análise , Superóxidos/análise , Tocoferóis/análise
17.
J Sci Food Agric ; 92(14): 2800-10, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22278616

RESUMO

BACKGROUND: The increasing interest in organic food products and environmental friendly practices has emphasised the importance of selecting crop varieties suitable for the low-input sector. Moreover, in recent years the relationship between diet and human health has gained much attention among consumers. The aim of this study was to comparatively evaluate the agronomic performance and the nutrient and phytochemical composition of old and modern Italian wheat genotypes grown under low-input management. RESULTS: Research highlighted that several old wheat genotypes were comparable to the modern ones in terms of agronomic performance and nutrient content. Genotype and environmental conditions (growing season), as well as their interaction, significantly affected the phytochemical composition of wheat grains for most of the analysed bioactive compounds. High variability was observed among the wheat genotypes for dietary fibre (154.7-183.3 g kg⁻¹), polyphenol (1.94-2.77 mg g⁻¹), tocopherol (9.1-21.2 mg kg⁻¹) and carotenoid (701.4-3243 µg kg⁻¹) content. CONCLUSION: The comparative study of old and modern wheat varieties highlighted that, under low-input conditions, ancient genotypes may equal modern ones in terms of agronomic traits and additionally provide nutraceutical value-added wheat grains. The most promising ancient varieties for the unique phytochemical profiles are Gentil rosso, Marzuolo d'aqui and Verna.


Assuntos
Qualidade dos Alimentos , Alimento Funcional/análise , Química Verde , Agricultura Orgânica/métodos , Sementes/crescimento & desenvolvimento , Triticum/crescimento & desenvolvimento , Antioxidantes/análise , Antioxidantes/metabolismo , Carotenoides/análise , Carotenoides/metabolismo , Produtos Agrícolas/química , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , Fibras na Dieta/análise , Fibras na Dieta/metabolismo , Farinha/análise , Alimentos Orgânicos/análise , Humanos , Itália , Valor Nutritivo , Polifenóis/análise , Polifenóis/metabolismo , Reprodutibilidade dos Testes , Estações do Ano , Sementes/química , Sementes/metabolismo , Especificidade da Espécie , Tocoferóis/análise , Tocoferóis/metabolismo , Triticum/química , Triticum/metabolismo
18.
J Food Sci ; 76(9): C1239-44, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22416683

RESUMO

UNLABELLED: The antioxidant activity of ethanolic extracts of parsley, buckthorn, mint, caraway, and their mixture "Vitalplant" was evaluated, and the potential of "Vitalplant" mixture extract to retard the process of lipid oxidation in cookies was tested. The antioxidant activity was estimated by 2 direct (ESR) and 4 indirect (spectrophotometric) tests and correlated with the total phenolic and flavonoid content. The potential of "Vitalplant" mixture extract to retard the process of lipid oxidation in cookies was measured by thiobarbituric acid (TBA)-reactive-substances assay (TBARS) and DPPH˙ (1,1-diphenyl-2-picryl-hydrazyl) test. Significantly different (P < 0.05) amounts of total phenolics were found among extracts in the following order: mint > buckthorn > "Vitalplant" > parsley > caraway. Total flavonoid content varied from 0.510% (parsley) to 2.05% ("Vitalplant"). A statistically significant correlation was found between IC(50) values on DPPH˙ and total flavonoid content of the samples (r=- 0.94, P < 0.05) and between IC(50) values on DPPH˙ and IC(50) values on O(2) (·-) scavenging activity (r= 0.89, P < 0.05). A correlation between reducing activity and total phenolic content was found to be positive and statistically significant (r= 0.94, P < 0.05). "Vitalplant" mixture exhibited a relatively high antioxidant activity in most of the tests, which can be explained by synergistic effects of the ingredients of which it is composed. Finally, "Vitalplant" extract addition (2%, 4%, and 6%) improved antioxidant activity and oxidative stability of the cookies in dose-dependent manner. PRACTICAL APPLICATION: Supplementation of cookies with a mixture of Petroselini fructus, Frangulae cortex, Mentha piperitae folium, Carvi fructus can retard the process of lipid oxidation and elevate antioxidant activity of the final product.


Assuntos
Antioxidantes/análise , Flavonoides/análise , Análise de Alimentos , Fenóis/análise , Extratos Vegetais/análise , Plantas Medicinais/química , Antioxidantes/metabolismo , Carum/química , Cromatografia Líquida de Alta Pressão , Suplementos Nutricionais , Mentha/química , Oxirredução , Petroselinum/química , Casca de Planta/química , Extratos Vegetais/metabolismo , Folhas de Planta/química , Substâncias Reativas com Ácido Tiobarbitúrico/análise
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