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1.
Food Funct ; 13(2): 664-674, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-34933325

RESUMO

We prepared a detoxified rapeseed protein isolate (RPI) by phytase/ethanol treatment based on alkaline extraction and acidic precipitation. Contents of protein, fat, ash, moisture, crude fiber, glucosinolates, phytic acid, and phenolics and color were determined. To evaluate the safety of detoxified RPI, five groups of C57 mice (detoxified RPI [10 and 20 g kg-1]; commercial soybean protein isolate (SPI) [10 g kg-1]; non-detoxified RPI [10 g kg-1]; control) were used in the acute-toxicity test. Bodyweight and pathology parameters were recorded at different time points, followed by macroscopic examination, organ-weight measurement and microstructure examination. After pretreatment of rapeseed meals with phytase (enzyme : substrate ratio, 1 : 5 mg g-1) for 1.5 h and two-time ethanol extraction for precipitated protein, the chemical characteristics in RPI were protein (88.26%), fat (0.57%), ash (2.72%), moisture (1.90%), crude fiber (0.77%), glucosinolates (0 µmol g-1), phytic acid (0.17%), phenolics (0.36%) and whiteness (73.38). Treatment resulted in significant removal of anti-nutritional factors (ANFs) and increased whiteness in detoxified RPI compared with non-detoxified RPI, and lower than in cruciferin-rich canola protein isolate (Puratein®). Experimental-related effects on bodyweight, clinical observations, or clinicopathology, in mice treated with detoxified RPI were not observed except for a decreased thyroid gland/parathyroid gland index in mice treated with non-detoxified RPI. Furthermore, the no-observed-effect level (NOEL) was 10 g kg-1 of detoxified RPI, whereas the no-observed-adverse-effect-level (NOAEL) was the highest fed level of 20 g kg-1 of detoxified RPI. Overall, detoxified RPI prepared by the combined treatment of phytase and ethanol was considered safe under the conditions tested, in which the contents of the main ANFs were reduced significantly.


Assuntos
Brassica napus/química , Glucosinolatos , Extratos Vegetais , Proteínas de Plantas , Animais , Peso Corporal/efeitos dos fármacos , Feminino , Glucosinolatos/análise , Glucosinolatos/química , Glucosinolatos/isolamento & purificação , Glucosinolatos/toxicidade , Masculino , Camundongos , Tamanho do Órgão/efeitos dos fármacos , Extratos Vegetais/análise , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Proteínas de Plantas/análise , Proteínas de Plantas/química , Proteínas de Plantas/toxicidade
2.
Molecules ; 26(22)2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34833884

RESUMO

Rapeseed meal (RSM), a by-product of oilseed extraction connected to the agri-food and biofuel sectors, is currently used as animal feed and for other low-value purposes. With a biorefinery approach, RSM could be valorized as a source of bio-based molecules for high-value applications. This study provides a chemical characterization of RSM in the perspective of its valorization. A qualitative study of main functional groups by fourier transform infrared (FTIR) spectroscopy was integrated with a chemical characterization of macronutrients, minerals by inductively coupled plasma optical emission spectrometry (ICP-OES), phenolic acids and lipid components by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), HPLC-diode-array detector (HPLC-DAD) and gas chromatography-mass spectrometry/flame ionization detector (GC-MS/FID). The study, conducted on different lots of RSM collected over a one-year period from an oil pressing factory serving a biofuel biorefinery, highlighted a constant quality over time of RSM, characterized by high protein (31-34%), fiber (33-40%) and mineral (5.5-6.8%) contents. Polyphenol extracts showed a significant antioxidant activity and a prevalence of sinapic acid, accounting for more than 85% of total phenolic acids (395-437 mg kg-1 RSM). Results highlight the potentialities of RSM for further valorization strategies that may lead to the creation of new cross-sector interconnections and bio-based value chains with improvement of the economics and sustainability of the bioeconomy sectors involved.


Assuntos
Brassica napus/química , Resíduos Industriais/análise , Gerenciamento de Resíduos/métodos , Ração Animal/análise , Antioxidantes/química , Biocombustíveis/análise , Brassica napus/metabolismo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Resíduos Industriais/economia , Minerais/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Espectrometria de Massas em Tandem/métodos , Resíduos/análise
3.
J Environ Sci Health B ; 55(8): 726-731, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32558617

RESUMO

It is crucial to develop practical procedures for the control and reduction of pesticide residues in oil productions from farm to dining table. In this study, the dissipation behaviors of typical fungicide from rapeseed to oil production were studied to reveal relationship among spraying stage, application dosage, household oil processing stage, and pesticide residues. In the field trials, rape plants were sprayed with carbendazim at three different dosages during flowering period. Transfer assessment of carbendazim residues from rapeseed to oil production during household oil processing via different press techniques was determined using high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS). The recoveries of carbendazim in rapeseed samples, meals after squeezing samples, and rapeseed oil samples ranged from 82.5% to 93.6% with relative standard deviations (RSDs) <5.2%. The validation results illustrated that the methods were reliable and sensitive. The average processing factor (PF) during household oil processing via hot press technique and cold press technique was 0.15 and 0.51, respectively. This study demonstrated that household oil processing could significantly reduce the pesticide residues, especially by hot press technique.


Assuntos
Benzimidazóis/análise , Carbamatos/análise , Contaminação de Alimentos/análise , Manipulação de Alimentos/métodos , Resíduos de Praguicidas/análise , Óleo de Brassica napus/análise , Brassica napus/química , Cromatografia Líquida de Alta Pressão/métodos , Características da Família , Fungicidas Industriais/análise , Óleo de Brassica napus/química , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
4.
Food Chem ; 316: 126355, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32066071

RESUMO

The lipolytic activity in oil body creams as affected by recovery and washing protocols was investigated. The effect of thermal treatment on the hydrolytic activity and physical stability of fresh and aged (up to 30 days) oil body emulsions was studied. The use of alkaline pH solutions (9.5) to soak and grind rapeseeds were more effective reducing the contamination of oil body material from seed proteins/enzymes, compared with neutral pHs. Soaking and grinding seeds with a NaHCO3 solution (0.1 M, pH 9.5) yielded oil bodies with a similar composition to those prepared in urea (9 M); however, the physical stability over storage was compromised due to the presence of hydrolytic enzymes. Heating a dispersion of oil bodies for 6 mins at 95 °C did not alter the physical properties of oil bodies and significantly reduced lipolytic activity (>90% enzyme inactivation), resulting in a stable emulsion.


Assuntos
Brassica napus/química , Brassica rapa/química , Gotículas Lipídicas/química , Óleo de Brassica napus/química , Emulsões/química , Lipólise , Sementes/química
5.
Microb Biotechnol ; 12(4): 752-762, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31012266

RESUMO

Late embryogenesis abundant (LEA) proteins play a protective role during desiccation and oxidation stresses. LEA3 proteins are a major group characterized by a hydrophilic domain (HD) with a highly conserved repeating 11-amino acid motif. We compared four different HD orthologs from distant organisms: (i) DrHD from the extremophilic bacterium Deinococcus radiodurans; (ii) CeHD from the nematode Caenorhabditis elegans; (iii) YlHD from the yeast Yarrowia lipolytica; and (iv) BnHD from the plant Brassica napus. Circular dichroism spectroscopy showed that all four HDs were intrinsically disordered in phosphate buffer and then folded into α-helical structures with the addition of glycerol or trifluoroethanol. Heterologous HD expression conferred enhanced desiccation and oxidation tolerance to Escherichia coli. These four HDs protected the enzymatic activities of lactate dehydrogenase (LDH) by preventing its aggregation under desiccation stress. The HDs also interacted with LDH, which was intensified by the addition of hydrogen peroxide (H2 O2 ), suggesting a protective role in a chaperone-like manner. Based on these results, the HDs of LEA3 proteins show promise as protectants for desiccation and oxidation stresses, especially DrHD, which is a potential ideal stress-response element that can be applied in synthetic biology due to its extraordinary protection and stress resistance ability.


Assuntos
Proteínas de Bactérias/química , Proteínas de Caenorhabditis elegans/química , Proteínas Fúngicas/química , Proteínas de Plantas/química , Animais , Proteínas de Bactérias/isolamento & purificação , Brassica napus/química , Caenorhabditis elegans/química , Proteínas de Caenorhabditis elegans/isolamento & purificação , Dicroísmo Circular , Clonagem Molecular , Desidratação , Deinococcus/química , Escherichia coli/genética , Escherichia coli/fisiologia , Proteínas Fúngicas/isolamento & purificação , Expressão Gênica , Viabilidade Microbiana , Estresse Oxidativo , Proteínas de Plantas/isolamento & purificação , Conformação Proteica , Dobramento de Proteína , Estresse Fisiológico , Yarrowia/química
6.
Sensors (Basel) ; 18(9)2018 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-30134620

RESUMO

This study considers whether a relationship exists between response to lithium (Li) exposure and select vegetation indices (VI) determined from reflectance spectra in each of four plant species: Arabidopsis thaliana, Helianthus annuus (sunflower), Brassica napus (rape), and Zea mays (corn). Reflectance spectra were collected every week for three weeks using an ASD FieldSpec Pro spectroradiometer with both a contact probe (CP) and a field of view probe (FOV) for plants treated twice weekly in a laboratory setting with 0 mM (control) or 15 mM of lithium chloride (LiCl) solution. Plants were harvested each week after spectra collection for determination of relevant physical endpoints such as relative water content and chlorophyll content. Mixed effects analyses were conducted on selected endpoints and vegetation indices (VI) to determine the significance of the effects of treatment level and length of treatment as well as to determine which VI would be appropriate predictors of treatment-dependent endpoints. Of the species considered, A. thaliana exhibited the most significant effects and corresponding shifts in reflectance spectra. Depending on the species and endpoint, the most relevant VIs in this study were NDVI, PSND, YI, R1676/R1933, R750/R550, and R950/R750.


Assuntos
Arabidopsis/efeitos dos fármacos , Brassica napus/efeitos dos fármacos , Helianthus/efeitos dos fármacos , Cloreto de Lítio/farmacologia , Zea mays/efeitos dos fármacos , Arabidopsis/química , Brassica napus/química , Clorofila/análise , Helianthus/química , Água/análise , Zea mays/química
7.
J Sci Food Agric ; 98(11): 4050-4057, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29385269

RESUMO

BACKGROUND: Very few near-infrared reflectance spectroscopy (NIRS) calibration models are available for non-destructive estimation of seed quality traits in Brassica juncea. Those that are available also fail to adequately discern variation for oleic acid (C18:1 ), linolenic (C18:3 ) fatty acids, meal glucosinolates and phenols. We report the development of a new NIRS calibration equation that is expected to fill the gaps in the existing NIRS equations. RESULTS: Calibrations were based on the reference values of important quality traits estimated from a purposely selected germplasm set comprising 240 genotypes of B. juncea and 193 of B. napus. We were able to develop optimal NIRS-based calibration models for oil, phenols, glucosinolates, oleic acid, linoleic acid and erucic acid for B. juncea and B. napus. Correlation coefficients (RSQ) of the external validations appeared greater than 0.7 for the majority of traits, such as oil (0.766, 0.865), phenols (0.821, 0.915), glucosinolates (0.951, 0.986), oleic acid (0.814. 0.810), linoleic acid (0.974, 0.781) and erucic acid (0.963, 0.943) for B. juncea and B. napus, respectively. CONCLUSION: The results demonstrate the robust predictive power of the developed calibration models for rapid estimation of many quality traits in intact rapeseed-mustard seeds which will assist plant breeders in effective screening and selection of lines in quality improvement breeding programmes. © 2018 Society of Chemical Industry.


Assuntos
Brassica napus/química , Ácidos Graxos/química , Glucosinolatos/química , Mostardeira/química , Fenóis/química , Óleos de Plantas/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Brassica napus/classificação , Mostardeira/classificação , Extratos Vegetais/química , Sementes/química , Sementes/classificação
8.
Anal Chem ; 90(3): 1777-1785, 2018 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-29298045

RESUMO

This work describes a simple approach for the untargeted profiling of volatile compounds for the authentication of the botanical origins of honey based on resolution-optimized HS-GC-IMS combined with optimized chemometric techniques, namely PCA, LDA, and kNN. A direct comparison of the PCA-LDA models between the HS-GC-IMS and 1H NMR data demonstrated that HS-GC-IMS profiling could be used as a complementary tool to NMR-based profiling of honey samples. Whereas NMR profiling still requires comparatively precise sample preparation, pH adjustment in particular, HS-GC-IMS fingerprinting may be considered an alternative approach for a truly fully automatable, cost-efficient, and in particular highly sensitive method. It was demonstrated that all tested honey samples could be distinguished on the basis of their botanical origins. Loading plots revealed the volatile compounds responsible for the differences among the monofloral honeys. The HS-GC-IMS-based PCA-LDA model was composed of two linear functions of discrimination and 10 selected PCs that discriminated canola, acacia, and honeydew honeys with a predictive accuracy of 98.6%. Application of the LDA model to an external test set of 10 authentic honeys clearly proved the high predictive ability of the model by correctly classifying them into three variety groups with 100% correct classifications. The constructed model presents a simple and efficient method of analysis and may serve as a basis for the authentication of other food types.


Assuntos
Cromatografia Gasosa/métodos , Mel/análise , Mel/classificação , Espectrometria de Mobilidade Iônica/métodos , Compostos Orgânicos Voláteis/análise , Brassica napus/química , Flores/química , Análise de Componente Principal , Robinia/química
9.
Environ Sci Pollut Res Int ; 25(1): 877-886, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29067611

RESUMO

A sensitive and selective method was developed and validated for the determination of pyrethrin residues in turnips (turnip leaves, turnip tubers, and the whole of plant) and cultivated soil using gas chromatography coupled with mass spectrometry (GC-MS). Six major components of pyrethrins (pyrethrin I and II, cinerin I and II, and jasmolin I and II) were separated and identified. The method involving solid-phase extraction (SPE) cleanup led to satisfactory average recoveries (88.1-104%) with limits of quantification (LOQs) of 0.05 mg/kg. The dissipation and final residue of pyrethrins in six provinces (among these places, two experiments were conducted in greenhouse and other four experiments in open filed) in China were studied. The trial results suggested that the half-lives of pyrethrins in the whole of turnips and soil were 0.5-1.6 and 1.0-1.3 days, respectively, and the degradation of pyrethrins in the greenhouse was quicker than that in open fields. The final residues of pyrethrins in turnip leaves and tubers were all below the maximum residue limit (MRL) established by the EU (1.0 mg/kg). A pre-harvest interval of 2 days and MRL of 1.0 mg/kg are recommended to ensure food safety standards for pyrethrins in turnips. Long-term risk assessment and short-term risk assessment of turnip tubers were evaluated. Hazard quotient (HQ) and acute hazard index (aHI) were significantly less than 100%, indicating negligible risk for consumption of turnip tubers.


Assuntos
Brassica napus/química , Monitoramento Ambiental , Resíduos de Praguicidas/análise , Piretrinas/análise , Medição de Risco , Poluentes do Solo/análise , Solo/química , Brassica napus/metabolismo , China , Cromatografia Gasosa-Espectrometria de Massas , Meia-Vida , Humanos , Resíduos de Praguicidas/metabolismo , Resíduos de Praguicidas/normas , Piretrinas/metabolismo , Poluentes do Solo/metabolismo
10.
Ecotoxicol Environ Saf ; 126: 193-201, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26771531

RESUMO

Soil heavy metals and their bioaccumulation in agricultural products have attracted widespread concerns, yet the transfer and accumulation characteristics of heavy metals in different soil-crop systems was rarely investigated. Soil and crop samples were collected from the typical agricultural areas in the Yangtze River Delta region, China. The concentrations of Cu, Pb, Zn, Cd and Hg in the soils, roots and grains of rice (Oryza Sativa L.), wheat (Triticum L.) and canola (Brassica napus L.) were determined in this study. Transfer ability of heavy metals in soil-rice system was stronger than those in soil-wheat and soil-canola systems. The wheat showed a strong capacity to transfer Zn, Cu and Cd from root to the grain while canola presented a restricting effect to the intake of Cu and Cd. Soil pH and total organic matter were major factors influencing metal transfer from soil to rice, whereas soil Al2O3 contents presented a negative effect on heavy metal mobility in wheat and canola cultivation systems. The concentration of Zn and Cd in crop grains could well predicted according to the stepwise multiple linear regression models, which could help to quantitatively evaluate the ecologic risk of heavy metal accumulation in crops in the study area.


Assuntos
Produtos Agrícolas/química , Metais Pesados/análise , Poluentes do Solo/análise , Brassica napus/química , China , Desenvolvimento Industrial , Oryza/química , Solo/química , Triticum/química
11.
Food Chem ; 197(Pt A): 482-8, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26616978

RESUMO

Oil seed, which is a secondary product in phytoremediation, contaminated with heavy metals should be disposed of in an appropriate fashion. In this study, heavy metal concentrations found in oilseed rape and peanut oils were below 0.1 mg kg(-1) after extractions, being found most of the heavy metals in meals rather in oils. Extraction experiments were carried out to determine the optimum methodology for the removal of Pb and Cd from seed meals using K3C6H5O7, K2C4H4O6 and (NH4)2EDTA. The highest extraction of the Pb and Cd in the seed meals was achieved using 30 mM extractant solutions at 30°C for 24 h and a three-step extraction procedure. K3C6H5O7 and K2C4H4O6 had less impact on the removal of nutrients than (NH4)2EDTA.


Assuntos
Brassica napus/química , Cádmio/análise , Contaminação de Alimentos/análise , Chumbo/análise , Óleos de Plantas/química , Sementes/química , Cádmio/isolamento & purificação , Chumbo/isolamento & purificação
12.
Food Chem ; 173: 185-93, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25466011

RESUMO

The effects of selenium, putrescine, and cadmium on the contents of glucosinolates, total phenolics, flavonoids, carotenoids, chlorophyll, anthocyanin, malondialdehyde, hydrogen peroxide, and antioxidant capacities as well as gene regulation of phenolics, flavonoids, carotenoids, and glucosinolates biosynthesis were investigated in turnip plants. Selenium dioxide (SeO2) treatment significantly induced the amount of gluconasturtiin, glucobrassicanapin, glucoallysin, glucobrassicin, 4-methoxyglucobrassicin, and 4-hydroxyglucobrassicin. Cadmium chloride (CdCl2)- and putrescine-treated plants had considerably enhanced gluconasturtiin and 4-hydroxyglucobrassicin levels, respectively. Total phenolic and flavonoid content as well as antioxidant capacities were significantly increased in SeO2-treated plants. Lutein was higher in control plants followed by, in decreasing order, SeO2-, putrescine-, and CdCl2-treated plants. The chlorophyll content was significantly decreased and anthocyanin, MDA, and H2O2 levels were significantly increased with CdCl2 treatment. Moreover, plants treated with selenium and cadmium showed significant induction of genes related to glucosinolate, phenolic, and carotenoid biosynthesis. These results demonstrated that SeO2 significantly increased the contents of health-promoting compounds and enhanced the antioxidant capacities of turnip plants.


Assuntos
Brassica napus/química , Brassica napus/efeitos dos fármacos , Cloreto de Cádmio/farmacologia , Putrescina/farmacologia , Óxidos de Selênio/farmacologia , Carotenoides/análise , Carotenoides/biossíntese , Clorofila/análise , Flavonoides/análise , Glucosinolatos/análise , Glucosinolatos/biossíntese , Promoção da Saúde , Luteína/análise , Malondialdeído/análise , Fenóis/análise
13.
J Sci Food Agric ; 94(4): 736-43, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24105894

RESUMO

BACKGROUND: Camelina sativa (CS) is an oilseed crop used for biofuel production. By-products from oil extraction are high in protein and can be used in ruminant rations; more information about their nutritive value is required also considering the antinutrional factor content of the by-products. The aim of this study was to evaluate the nutritive value of CS meal genotypes in comparison with canola. RESULTS: Ten CS genotypes and one canola cultivar were evaluated. Meals were obtained from seeds after solvent oil extraction. CS average crude protein (CP) content (g kg⁻¹ dry matter) was 457. Numerical differences in lysine and sulfur amino acid content were observed among CS genotypes. Glucosinolate (mmol kg⁻¹) content was higher for CS (23.1) than canola (7.2). Sinapine content (g kg⁻¹) was lower for CS (2.79) than for canola (4.32). Differences were observed among CS genotypes for rumen undegraded protein (RUP). Average RUP (g kg⁻¹ CP) was 316 for CS and 275 for canola. CONCLUSIONS: CS meal has potential for use in ruminant rations as a high-quality protein source. In vivo studies are needed to compare CS with other protein sources used in cattle rations. Implementation of breeding programs for improved meal quality is recommend.


Assuntos
Ração Animal/análise , Brassicaceae/química , Produtos Agrícolas/química , Proteínas Alimentares/análise , Proteínas de Plantas/análise , Ruminantes/fisiologia , Sementes/química , Ração Animal/efeitos adversos , Ração Animal/economia , Animais , Brassica napus/química , Brassica napus/genética , Brassica napus/crescimento & desenvolvimento , Brassica napus/metabolismo , Brassicaceae/genética , Brassicaceae/crescimento & desenvolvimento , Brassicaceae/metabolismo , Colina/efeitos adversos , Colina/análogos & derivados , Colina/análise , Colina/metabolismo , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/metabolismo , Fibras na Dieta/efeitos adversos , Fibras na Dieta/análise , Fibras na Dieta/economia , Fibras na Dieta/metabolismo , Proteínas Alimentares/química , Proteínas Alimentares/economia , Proteínas Alimentares/metabolismo , Digestão , Indústria de Processamento de Alimentos/economia , Variação Genética , Glucosinolatos/efeitos adversos , Glucosinolatos/análise , Glucosinolatos/metabolismo , Resíduos Industriais/análise , Resíduos Industriais/economia , Itália , Valor Nutritivo , Ácido Fítico/efeitos adversos , Ácido Fítico/análise , Ácido Fítico/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/economia , Proteínas de Plantas/metabolismo , Proantocianidinas/efeitos adversos , Proantocianidinas/análise , Proantocianidinas/metabolismo , Proteólise , Rúmen/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo
14.
Talanta ; 112: 85-94, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23708542

RESUMO

A robust, reliable and high-throughput method for extraction and purification of gibberellins (GAs), a group of tetracyclic diterpenoid carboxylic acids that include endogenous growth hormones, from plant material was developed. The procedure consists of two solid-phase extraction steps (Oasis(®) MCX-HLB and Oasis(®) MAX) and gives selective enrichment and efficient clean-up of these compounds from complex plant extracts. The method was tested with plant extracts of Brassica napus and Arabidopsis thaliana, from which total recovery of internal standards of about 72% was achieved. A rapid baseline chromatographic separation of 20 non-derivatised GAs by ultra performance liquid chromatography is also presented where a reversed-phase chromatographic column Acquity CSH(®) and a mobile phase consisting of methanol and aqueous 10mM-ammonium formate is used. This method enables sensitive and precise quantitation of GAs by MS/MS in multiple-reaction monitoring mode (MRM) by a standard isotope dilution method. Optimal conditions, including final flow rate, desolvation temperature, desolvation gas flow, capillary and cone voltage for effective ionisation in the electrospray ion source were found. All studied GAs were determined as free acids giving dominant quasi-molecular ions of [M-H](-) with limits of detection ranging between 0.08 and 10 fmol and linear ranges over four orders of magnitude. Taking advantage of highly effective chromatographic separation of 20 GAs and very sensitive mass spectrometric detection, the presented bioanalytical method serves as a useful tool for plant biologists studying the physiological roles of these hormones in plant development.


Assuntos
Arabidopsis/química , Brassica napus/química , Giberelinas/análise , Extratos Vegetais/análise , Cromatografia Líquida/métodos , Flores/química , Brotos de Planta/química , Extração em Fase Sólida , Espectrometria de Massas em Tandem/métodos
15.
Chemosphere ; 77(4): 582-9, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19625069

RESUMO

Following application, pesticides can be intercepted and absorbed by weeds and/or crops. Plants containing pesticides residues may then reach the soil during the crop cycle or after harvest. However, the fate in soil of pesticides residues in plants is unknown. Two commonly used foliar herbicides, glyphosate and sulcotrione, (14)C-labeled, were applied on leaves of oilseed rape and/or maize, translocation was studied, and then soil incubations of aerial parts of plants containing herbicides residues were performed. Soil treated directly with herbicides was used as control. The effects of adjuvants on herbicide plant-absorption and subsequent soil-degradation were also investigated comparing herbicides application as active ingredients and as commercial formulations. The fate in soil of herbicides residues in plants was different from that of control, and different for glyphosate and sulcotrione. Mineralization in soil of glyphosate in crops decreased compared to control, and amounts of (14)C-extractable residues, mainly composed by the metabolite aminomethylphosphonic acid (AMPA), and non-extractable residues (NER) increased. In contrast, mineralization in soil of sulcotrione in maize increased compared to control, with a decrease in the (14)C-extractable residues and an increase in NER. The fate of both herbicides was influenced by the type of plant organ in which herbicide was incorporated, because of differences in herbicides bioavailability and organs biodegradability, but not by adjuvants. Absorption of both herbicides in plant delays their subsequent soil-degradation, and particularly, glyphosate persistence in soil could increase from two to six times. The modifications of herbicide degradation in soil due to interception by plants should be considered for environmental risks assessment.


Assuntos
Cicloexanonas/metabolismo , Glicina/análogos & derivados , Herbicidas/metabolismo , Mesilatos/metabolismo , Poluentes do Solo/metabolismo , Solo , Adsorção , Biodegradação Ambiental , Brassica napus/química , Brassica napus/metabolismo , Cicloexanonas/química , Monitoramento Ambiental , Glicina/química , Glicina/metabolismo , Herbicidas/química , Mesilatos/química , Medição de Risco , Microbiologia do Solo , Poluentes do Solo/química , Glifosato
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