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1.
J Chromatogr A ; 1717: 464687, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38310698

RESUMO

The use of multiple names for multi-scope analytical methods is often confusing. More precise classification to better accommodate the scope of analytical validation and application is needed.


Assuntos
Nomes , Semântica
2.
Front Nutr ; 10: 1241105, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37743913

RESUMO

Grape pomace, the main by-product of wine process, shows high potential for the development of functional foods, being a natural source of bioactive compounds and dietary fiber. Thus, the present study proposes the development of five potential functional biscuits. The five formulations were achieved by varying the Tannat grape pomace powder (TGP, 10-20% w/w total wet dough) and sweetener sucralose (2-4% w/w total wet dough) content through a factorial design with central points. TGP microbiological and pesticides analysis were performed as a food safety requirement. Identification of bioactive compounds by HPLC-DAD-MS, in vitro bioactivity (total phenol content, antioxidant by ABTS and ORAC-FL, antidiabetic and antiobesity by inhibition of α-glucosidase and pancreatic lipase, respectively) and sensory properties of the biscuits were evaluated. TGP microbiological and pesticides showed values within food safety criteria. Sensory profiles of TGP biscuits were obtained, showing biscuits with 20% TGP good sensory quality (7.3, scale 1-9) in a cluster of 37 out of 101 consumers. TGP addition in biscuits had a significant (p < 0.05) effect on total phenolic content (0.893-1.858 mg GAE/g biscuit) and bioactive properties when compared to controls: 11.467-50.491 and 4.342-50.912 µmol TE/g biscuit for ABTS and ORAC-FL, respectively; inhibition of α-glucosidase and pancreatic lipase, IC50 35.572-64.268 and 7.197-47.135 mg/mL, respectively. HPLC-DAD-MS results showed all the identified phenolic compounds in 20/4% biscuit (TGP/sucralose%) were degraded during baking. Malvidin-3-O-(6'-p-coumaroyl) glucoside, (+)-catechin, malvidin-3-O-glucoside, and (-)-epicatechin were the main phenolic compounds (in descendent order of content) found. The bioactive properties could be attributed to the remaining phenolic compounds in the biscuits. In conclusion, TGP biscuits seemed to be a promising functional food with potential for ameliorating oxidative stress, glucose and fatty acids levels with good sensory quality.

3.
Talanta ; 260: 124647, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37172434

RESUMO

Manuka honey is a valuable commodity produced by bees foraging the flowers of Leptospermum scoparium, a bush native to New Zealand and Australia. Due to its high value and proven health benefits, authenticity fraud in the sale of this food is a significant risk, as recounted in the literature. Four compulsory natural products must be present at minimum concentrations to authenticate manuka honey (3-phenyllactic acid, 2'-methoxyacetophenone, 2-methoxybenzoic acid, and 4-hydroxyphenyllactic acid). However, spiking other kinds of honey with these compounds and/or the dilution of manuka honey with other varieties may result in fraud going undetected. In this work, liquid chromatography coupled with high-resolution mass spectrometry and a metabolomics-based strategy has allowed us to tentatively identify 19 natural products -putative manuka honey markers-, nine of which are reported for the first time. Chemometric models applied to these markers allowed the detection of both spiking and dilution fraud attempts of manuka honey, even at 75% manuka honey purity. Thus, the herein-reported methodology can be employed in the prevention and detection of manuka honey adulteration even at low levels, and the tentatively identified markers presented in this work proved valuable for manuka honey authentication procedures.


Assuntos
Produtos Biológicos , Mel , Abelhas , Animais , Mel/análise , Espectrometria de Massas , Cromatografia Líquida , Metabolômica
4.
Sci Total Environ ; 874: 162310, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-36828068

RESUMO

A pilot annual monitoring survey (April 2018-March 2019) was conducted to investigate the presence of pesticides in superficial water and fish in Laguna del Cisne, one of the most critical drinking water sources in Uruguay. A total of 25 pesticide residues were detected in superficial water (89.3 % of the samples). Pesticide's temporal distribution was associated with crops and livestock practices, with higher occurrences in spring and summer than in autumn and winter. The most frequent compounds in superficial water were the insecticide chlorantraniliprole, and the herbicides glyphosate (including its metabolite AMPA) and metolachlor. The levels of Organochlorine pesticide, p,p'-DDT, was in some cases two order of magnitude above the international water quality guidelines for Ambient Water Criteria. In fishes, eight different pesticides were detected, at concentrations from 1000 to 453,000 ng·kg-1. The most frequent pesticides found were propiconazole, chlorpyrifos, and p,p'-DDE. The widespread occurrence of pesticides in fish suggests potential exposure effects on fish populations and the aquatic ecosystem. The sampling approach of this work allowed monitoring the continuous concentrations of several pesticides in surface waters and fishes to establish the influence from past and current agriculture practices in Laguna del Cisne basin. For safety measures, continuous monitoring programs must be performed in this system to prevent toxicity impacts on aquatic organisms and human health.


Assuntos
Água Potável , Hidrocarbonetos Clorados , Praguicidas , Poluentes Químicos da Água , Animais , Humanos , Praguicidas/análise , Lagos , Uruguai , Ecossistema , Poluentes Químicos da Água/análise , Hidrocarbonetos Clorados/análise , DDT , Diclorodifenil Dicloroetileno , Monitoramento Ambiental
5.
Foods ; 11(16)2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-36010384

RESUMO

Recent advances in nuclear magnetic resonance (NMR) have led to the development of low-field benchtop NMR systems with improved sensitivity and resolution suitable for use in research and quality-control laboratories. Compared to their high-resolution counterparts, their lower purchase and running costs make them a good alternative for routine use. In this article, we show the adaptation of a method for predicting the consumer acceptability of mandarins, originally reported using a high-field 400 MHz NMR spectrometer, to benchtop 60 MHz NMR systems. Our findings reveal that both instruments yield comparable results regarding sugar and citric acid levels, leading to the development of virtually identical predictive linear models. However, the lower cost of benchtop NMR systems would allow cultivators to implement this chemometric-based method as an additional tool for the selection of new cultivars.

6.
Front Nutr ; 9: 868054, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35811969

RESUMO

Composition and antioxidant properties of sixteen pecan [Carya illinoinensis (Wangenh) K. Koch] cultivars grown simultaneously in a single experimental orchard in Uruguay were evaluated to characterize their nutritional properties and nutraceutical potential. The percentage of oil, moisture, ash, minerals, and proteins were determined and also the fatty acid profile. Total phenolic compounds [18-41 mg gallic acid equivalents (GAEs)/g], condensed tannin [2-12 mg catechin equivalents (CEs)/g], and tocopherols (110-163 µg/g) contents were estimated in nut kernels. Total phenolic compounds (32-117 mg GAE/g), condensed tannins (130-357 mg CE/g), and total anthocyanins (1-3 mg 3-glucoside cyanidin/g) were also determined for pecan shells. The antioxidant activity in shells [57.15-578.88 µmol Trolox equivalents (TEs)/g] was 5 times higher compared with the kernels (23.15-156.60 µmol TEs/g) measured with hydrophilic ORAC. Bioactive compounds concentrations present statistically significant genetic variability between cultivars studied (p < 0.05). The presence of phenolic compounds was related with high-antioxidant capacity in kernels and shells, and a strong correlation between content of total phenolic compounds and condensed tannins in pecan shells was found. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) show association between cultivars and the observed variables. The nutritional profile in the different cultivars showed the trends described in other countries, but this work shows some significant differences that could be attributed to the specific edaphoclimatic conditions of cultivation in Uruguay.

7.
MethodsX ; 9: 101697, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35518919

RESUMO

Contain between 1 and 3 bullet points highlighting the customization rather than the steps of the procedure. An analytical methodology was adjusted and validated for the analysis of 15 selected pesticides currently employed in extensive agriculture. The main application of this methodology is studying the pesticides degradation behavior using biobeds as a friendly environmental tool for the treatment of wastewaters generated in fields. The scope of the method was selected based on the most used pesticides in soybean crops in Uruguay. The novelty of this work is the inclusion of neutral and acidic herbicides such as 2,4-D, clethodim, dicamba, together with fungicides and insecticides which are usually included in Multi Residue Methods. An acetonitrile extraction methodology without a clean-up step yielded acceptable results for all the analytes. The instrumental analysis was performed using HPLC-MS/MS. The selected methodology was validated according to the SANTE guidelines. The recoveries were between 65 and 130% with RSD < 20%. The instrumental LOQs were fixed at 1 µg/L for all the compounds except for clethodim, and the method LOQs were 1 mg/kg in biomixture dry basis. These LOQs values are acceptable for biodegradation studies in biobeds. A multiresidue methodology was: • Validated for 15 pesticides in biomixture. • Acidic herbicides were included in the scope. • The method was employed for the environmental monitoring of pesticide degradation in biobeds.

8.
Foods ; 10(4)2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33921665

RESUMO

The growing incidence of non-communicable diseases makes the search for natural sources of bioactive compounds a priority for such disease prevention/control. Achyrocline satureioides ('marcela'), a plant rich in polyphenols and native to Brazil, Uruguay, Paraguay, and Argentina, could be used for this purpose. Data on its antidiabetic/antiobesity properties and cellular uptake of bioactive compounds are lacking. The potentiality of non-thermal technologies such as high-hydrostatic pressure (HP) to enhance polyphenol extraction retains attention. Thus, in the present study aqueous and ethanolic marcela extracts with/without assisted-HP processing were chemically characterized and assessed for their in vitro antioxidant capacity, antidiabetic and antiobesity activities, as well as cellular cytotoxicity and uptake on intestinal cell monolayers (TC7-cells, a clone of Caco-2 cells). Aqueous and ethanolic conventional extracts presented different polyphenolic profiles characterized mainly by phenolic acids or flavonoids, respectively, as stated by reverse phase-high-performance liquid chromatography (RP-HPLC) analyses. In general, ethanolic extracts presented the strongest bioactive properties and HP had none or a negative effect on in vitro bioactivities comparing to conventional extracts. TC7-cell viability and cellular uptake demonstrated in conventional and HP-assisted extracts, highlighted the biological effects of marcela bioactive compounds on TC7-cell monolayers. TC7-cell studies showed no HP-induced cytotoxicity. In sum, marcela extracts have great potential as functional ingredients for the prevention/treatment of chronic diseases such as diabetes.

9.
Acta Crystallogr E Crystallogr Commun ; 75(Pt 9): 1348-1351, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31523464

RESUMO

The structure of the title compound, C32H51NO6, was determined from 62-year-old crystals at room temperature and refined with 100 K data in a monoclinic (C2) space group. This compound with a triterpenoid structure, now confirmed by this study, played an important role in the determination of the structure of lanosterol. The mol-ecules pack in linear O-H⋯O hydrogen-bonded chains along the short axis (b), while parallel chains display weak van der Waals inter-actions that explain the needle-shaped crystal morphology. The structure exhibits disorder of the flexible methyl-heptane chain at one end of the main mol-ecule with a small void around it. Crystals of the compounds were resistant to data collection for decades with the available cameras and Mo Kα radiation single-crystal diffractometer in our laboratory until a new instrument with Cu Kα radiation operating at 100 K allowed the structure to be solved and refined.

10.
Rev. bras. farmacogn ; 29(4): 500-503, July-Aug. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1042273

RESUMO

Abstract Workflows based on gas and liquid chromatography coupled to mass spectrometry for the identification of toxic pyrrolizidine alkaloids present in plants were developed and applied to Echium plantagineum L., Boraginaceae, extracts. GC-MS based determinations need reduction and derivatization steps prior to MS analysis, which is performed using a Full Scan and Single Ion Monitoring sequence for screening, identification and quantification purposes. The LC-(ESI)-MS/MS determination was performed directly from the extract without derivatization. Acetyl lycopsamine, echimidine, echimidine N-oxide, echiumine, echiumine N-oxide, lycopsamine, lycopsamine N-oxide, 7,9-ditigloylretronecine N-oxide and a not reported PA of m/z 466, were identified and quantified in E. plantagineum extracts, through three operating modes of LC-QTRAP: precursor ion scan, enhanced product ion scan and multiple reaction monitoring. Precursor ion scan detects all the ions that give rise to a daughter ion at m/z 120, the presence of the parent pyrrolizidine alkaloid is confirmed through its MS2 spectrum (enhanced product ion) and quantified by multiple reaction monitoring. These workflows are general approaches to study chemical families using GC/LC-MS. For extracts suspicious of containing pyrrolizidine alkaloids, they are suitable tools for the quality and safety control of food, feed as well as phytotherapeutics.

11.
MethodsX ; 6: 929-937, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31080757

RESUMO

With the aim of monitoring multiclass semi-polar pesticide residues in freshwater fatty fish, two QuEChERS approaches (so-called acetate buffered and unbuffered versions) were evaluated for the determination of 77 pesticide residues. Compounds were selected according to the dominant rainfed agriculture activities in South America. Unbuffered QuEChERS was finally chosen for validation purposes owing that it provided the best results in terms of recovery yields. Method performance was evaluated in two instrumental systems, liquid chromatography - tandem mass spectrometry (LC-MS/MS) in Scheduled MRM™ algorithm available on hybrid quadrupole - linear ion trap (QLIT) instrument, and gas chromatography - mass spectrometry (GC-MS) under selected ion monitoring (SIM) mode. Spiking experiments were carried out to determine the trueness, precision, linearity, limit of quantification of the method as well as matrix effect. The Unbuffered QuECHERS method described here: •Was validated for the analysis of 67 pesticide residues in fish muscle tissue.•Presented quantification limits in the range 1-15 µg kg-1 for the vast majority of the studied compounds.•Enable environmental monitoring of pesticide residues in fish due to their low LOQs.

12.
ACS Omega ; 4(27): 22632-22637, 2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31909347

RESUMO

Contamination of honey with toxic pyrrolizidine alkaloids (PAs) and their N-oxides (PANOs) was assessed by dilution with acidic methanol and analysis through liquid chromatography (LC) coupled with tandem mass spectrometry (MS/MS) in three different modes. The hybrid linear trap/triple quadrupole (LC-QTRAP) instrument was used in precursor ion scan (PIS), enhanced product ion scan (EPI), and multiple reaction monitoring (MRM) mode. The parent ions from ions at m/z 120 or 138 amus, characteristic of all the toxic PAs and PANOs in the sample were first scanned by PIS. Then, the presence of each contaminant at specific retention times through its MS2 spectrum was confirmed by EPI. Finally, they were quantified in the MRM mode. The method was validated: recoveries 86-111%, relative standard deviation (RSD) <20%, at 20 and 40 µg/kg, except retrorsine, which showed a RSD of 30% at 20 µg/kg. Honey samples were analyzed and five of them showed levels of 40 µg/kg for the sum (PAs + PANOs). This approach allows the simultaneous determination of PAs and PANOs in honey, even if their chemical standards are not available.

13.
J Agric Food Chem ; 66(25): 6421-6430, 2018 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-29874915

RESUMO

A modified and miniaturized SweEt/QuEChERS method for pesticide residue analysis applied to vine leaves is presented. The deep-frozen plant material was cryogenically processed. A 2 g analytical portion was hydrated for 30 min and extracted with acidified ethyl acetate after buffering with NaHCO3 and adding Na2SO4. A dispersive solid-phase (d-SPE) cleanup step with primary-secondary amine (PSA) was performed. The pesticide residues were determined using GC-MS/MS. The whole procedure was validated for 54-59 pesticides at 0.01, 0.02, 0.1, and 0.2 mg/kg in fresh vine leaves ( Vitis vinifera). The key method performance parameters investigated were specificity, linearity, trueness, within laboratory repeatability and reproducibility, limit of detection, limit of quantitation, and matrix effects. Recoveries for the 59 pesticides tested ranged from 60 to 110%, and the RSDs were lower than 20% for the majority of the pesticides studied.


Assuntos
Cromatografia Gasosa/métodos , Resíduos de Praguicidas/química , Espectrometria de Massas em Tandem/métodos , Vitis/química , Folhas de Planta/química , Sensibilidade e Especificidade
14.
Foods ; 7(5)2018 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-29695116

RESUMO

The use of nutrient-rich foods to enhance the wellness, health and lifestyle habits of consumers is globally encouraged. Native fruits are of great interest as they are grown and consumed locally and take part of the ethnobotanic knowledge of the population. Pitanga is an example of a native fruit from Uruguay, consumed as a jelly or an alcoholic beverage. Pitanga has a red-violet pigmentation, which is a common trait for foods that are a good source of antioxidants. Hence, fruits from different Uruguayan regions were analyzed via miniaturized sample preparation method, HPLC-DAD-ESI/MSn and RP-HPLC-DAD techniques to identify and quantify phenolic compounds, respectively. The antioxidant capacity was evaluated via DPPH and ORAC (Oxygen Radical Absorbance Capacity) assays. A multivariate linear regression was applied to correlate the observed antioxidant capacity with the phenolic content. Furthermore, Principal Components Analysis was performed to highlight characteristics between the various samples studied. The main results indicated differences between northern and southern Uruguayan samples. Delphinidin-3-hexoside was present in southern samples (mean of 293.16 µmol/100 g dry weight (DW)) and absent in the sample collected in the north (sample 3). All the samples contain high levels of cyanidin-3-hexoside, but a noticeable difference was found between the northern sample (150.45 µmol/100 g DW) and the southern sample (1121.98 µmol/100 g DW). The antioxidant capacity (mean ORAC of 56370 µmol Trolox®/100 g DW) were high in all the samples compared to the Food and Drug Administration (FDA) database of similar berry-fruits. The results of this study highlight the nutraceutical value of a native fruit that has not been exploited until now.

15.
Sci Total Environ ; 631-632: 169-179, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29524894

RESUMO

Environmental sustainability of South American rainfed agroecosystems is of current concern. In this work, we evaluate the occurrence of multiple pesticide residues in muscle tissue of wild fish species from two large rivers in South America (Uruguay and Negro Rivers). Two sampling campaigns (representing summer and winter crops) were performed during 2015 targeting a wide biodiversity of fish species used for human consumption (ranging from migratory to non-migratory and from detritivorous to top-predators). Three different localities associated to rainfed agriculture were assessed, two of them enclosed to a RAMSAR site (National Park "Esteros de Farrapos e Islas del Rio Uruguay"). Pesticide residues occurred in muscle tissue of 143 from 149 sampled fishes (96%). Thirty different pesticides were detected at concentrations from <1 to 194µgkg-1. Incidence of pesticides in fish were tightly related to: i) features of the contaminant: (Kow, environmental persistence and mobility) and ii) intensity of use of particular pesticides and land dedicated to rainfed agriculture. Trifloxystrobin, metolachlor and pyraclostrobin showed the highest rates of occurrence. Of great concern is that strobirulins have highest toxicity to fish from those detected compounds. From the pattern of pesticides occurring for non-migratory fish species it was possible to trend important spatial differences related to the intensity of rainfed agriculture. Results suggest a regular exposition of aquatic wild biota to sublethal concentrations of multiple semi-polar pesticides.


Assuntos
Monitoramento Ambiental , Peixes/metabolismo , Resíduos de Praguicidas/metabolismo , Poluentes Químicos da Água/análise , Agricultura , Animais , Ecossistema , Resíduos de Praguicidas/análise , Praguicidas/análise , Praguicidas/metabolismo , Chuva , Rios/química , América do Sul , Poluentes Químicos da Água/metabolismo
16.
Talanta ; 178: 410-418, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29136841

RESUMO

The impacts of the modern, agrochemicals based agriculture that threatens the overall systems sustainability, need to be monitored and evaluated. Seeking for agroecosystems monitors, the present article focus in the occurrence and abundance of aquatic macroinvertebrates, that have been frequently used as bioindicators of water quality due to their relationship with land use. Some of these organisms are on the top of the food chain, where bioaccumulation and biomagnification processes can be observed, and they can turn into secondary pollution sources of systems and terrestrial organisms as well. Odonate nymphs, which belong to the functional group of predators, were selected for this study. A methodology to determine 73 pesticide residues in odonate nymphs by LC-MS/MS and GC-MS/MS was developed. A QuEChERS sample preparation strategy was adapted. As it is complex to obtain samples especially in disturbed ecosystems, the method was minimized to a sample size of 200mg of fresh nymphs. The method was validated and good recoveries (71-120%) with RSDs below 20% for the majority of the studied pesticides at least at two of the assayed levels 1, 10 and 50µgkg-1 were obtained. For 32 analytes the limit of quantitation was 1µgkg-1 and 10µgkg-1 for the others. The lineal range was observed between 1-100µgkg-1 in matrix-matched and solvent calibration curves for most of the assessed pesticides. LC-MS/MS matrix effects were evaluated, 40% of the analytes presented low or no signal suppression. Only flufenoxuron presented high matrix effects. The obtained methodology is adequate for pesticide multiresidue analysis in aquatic macroinvertebrates (odonates) aiming to contribute to the ecological state evaluation of freshwater ecosystems.


Assuntos
Ecossistema , Monitoramento Ambiental/métodos , Miniaturização , Ninfa/química , Paleópteros/química , Resíduos de Praguicidas/análise , Animais , Custos e Análise de Custo , Monitoramento Ambiental/economia , Resíduos de Praguicidas/isolamento & purificação , Extração em Fase Sólida , Espectrometria de Massas em Tandem
17.
J Agric Food Chem ; 65(23): 4819-4829, 2017 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-28541668

RESUMO

The matrix effects of ethyl acetate extracts from seven different citrus fruits on the determination of 80 pesticide residues using liquid chromatography coupled to high-resolution time-of-flight mass spectrometry (UHPLC-(ESI)-HR-TOF) at 4 GHz resolution mode were studied. Only 20% of the evaluated pesticides showed noticeable matrix effects (ME) due to coelution with natural products between tR = 3 and 11 min. Principal component analysis (PCA) of the detected coextractives grouped the mandarins and the orange varieties, but separated lemon, oranges, and mandarins from each other. Matrix effects were different among species but similar between varieties, forcing the determination of pesticide residues through matrix-matched calibration curves with the same fruit. Twenty-three natural products (synephrine, naringin, poncirin, glycosides of hesperitin, limonin, nomilin, and a few fatty acids, among others) were identified in the analyzed extracts. Twelve of the identified compounds coeluted with 28 of the pesticides under study, causing different matrix effects.


Assuntos
Citrus/química , Frutas/química , Resíduos de Praguicidas/química , Extratos Vegetais/química , Cromatografia Líquida de Alta Pressão , Citrus/classificação , Espectrometria de Massas , Estrutura Molecular
18.
Food Chem ; 227: 227-236, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28274427

RESUMO

Aiming to select the most suitable sample preparation for the multiresidue analysis of pesticides in globe artichoke (Cynara cardunculus L.), a modified QuEChERS, a matrix solid phase dispersion and a dispersive ethyl acetate extraction were compared. Trueness and precision were determined at 0.2mgkg-1 for the three methods. The modified QuEChERS showed the best performance. The scope of the method was enlarged to 35 GC and 63 LC amenable pesticides, its overall performance was evaluated and validated to artichoke leaves and fruits according to DG-SANTE Guidelines. Different matrix effects were observed for most of the pesticides which were higher for leaves than fruits. Difenoconazole and flutriafol suffered signal suppression in leaves extracts but showed positive matrix effects in fruits. All pesticides were analyzed at or below their Maximum Residue Levels fixed for globe artichoke by the European Union. The method was successfully applied for the analysis of commercial samples.


Assuntos
Cynara scolymus/química , Resíduos de Praguicidas/análise , Extração em Fase Sólida/métodos , Cromatografia Líquida , Frutas/química , Cromatografia Gasosa-Espectrometria de Massas , Resíduos de Praguicidas/isolamento & purificação , Folhas de Planta/química , Espectrometria de Massas em Tandem
19.
Sci Total Environ ; 581-582: 25-31, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28073057

RESUMO

The beehive as a quantitative monitor of pesticide residues applied over a soybean crop was studied through a semi field experiment of controlled exposure of honey bees to pesticides in macro tunnels. The distribution within exposed beehives of pesticides commonly used in soybean plantation, was assessed. Residue levels of insecticides in soybean leaves, honey bees, wax, honey and pollen were analyzed. The transference from pesticides present in the environment into the beehive was evidenced. The obtained results allow relating pesticide concentrations present in the environment with traces found in foraging bees. Therefore, pesticide transference ratios could be calculated for each detected compound (acetamiprid, imidacloprid and thiamethoxam) which showed a linear inverse trend with their 1-octanol/water partition coefficient (Kow). The least transferred pesticide to the hive (acetamiprid) has the highest vapor pressure (Vp). This study gives new insights on the usefulness of monitoring the environment through beehives aiming to evaluate if agroecosystems remain sustainable. It also contributes to generate valuable information for model building aiming to predict environmental quality through beehive's analysis.


Assuntos
Abelhas , Mel/análise , Neonicotinoides/análise , Resíduos de Praguicidas/análise , Animais , Folhas de Planta/química , Pólen/química , Ceras/análise
20.
J Toxicol Environ Health A ; 79(18): 825-36, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27587288

RESUMO

Grapes are one of the most commonly consumed fruit, in both fresh and processed forms; however, a significant amount is disposed of in the environment. Searching for a use of this waste, the antigenotoxic, antimutagenic, and antioxidant activities of aqueous extracts from organic and conventional Vitis labrusca leaves were determined using V79 cells as model. The antigenotoxic activity was analyzed by the alkaline comet assay using endonuclease III and formamidopyrimidine DNA glycosylase enzymes. The antimutagenic property was assessed through the micronucleus (MN) formation, and antioxidant activities were assessed using 2',7'-dichlorodihydrofluorescin diacetate (DCFH-DA) assay and 2,2-diphenyl-1-picrylhydrazyl (DPPH(●)) radical scavenging, as well as with superoxide dismutase (SOD) and catalase (CAT) activity assays. In addition, phenolic content and ascorbic acid levels of both extracts were determined. Data showed that both organic and conventional grapevine leaves extracts possessed antigenotoxic and antimutagenic properties. The extract of organic leaves significantly reduced intracellular reactive oxygen species (ROS) levels in V79 cells, and displayed greater ability for DPPH(●) scavenging and higher SOD and CAT activities than extract from conventional leaves. Further, the extract from organic leaves contained higher phenolic and ascorbic acid concentrations. In summary, extracts from organic and conventional grape leaves induced important in vitro biological effects.


Assuntos
Antimutagênicos/farmacologia , Antioxidantes/farmacologia , Ácido Ascórbico/análise , Agricultura Orgânica , Polifenóis/análise , Vitis/química , Animais , Linhagem Celular , Cricetulus , Testes para Micronúcleos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química
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