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1.
Biofortification of staple crops via breeding is an attractive strategy for reducing human micronutrient deficiencies. The objective of this research was to examine the concentration of carotenoids in diverse pea and chickpea accessions grown in Saskatchewan (Canada) using high performance liquid chromatography. In pea accessions mean concentration of lutein was highest (11.2 μg g−1) followed by β-carotene (0.5 μg g−1), zeaxanthin (0.3 μg g−1), and violaxanthin (0.3 μg g−1). Green cotyledon pea accessions were richer in β-carotene and total carotenoids compared to yellow cotyledon accessions. In chickpea accessions mean concentration of lutein (8.2 μg g−1) was highest followed by zeaxanthin (6.2 μg g−1), β-carotene (0.5 μg g−1), β-cryptoxanthin (0.1 μg g−1), and violaxanthin (0.1 μg g−1). Desi chickpea accessions had higher carotenoid concentration than kabuli accessions. This research identified pea and chickpea accessions that can be utilized in breeding for the improvement of carotenoid concentration through biofortification.  相似文献   

2.
This study evaluates the nutritional potential of Sarcocornia ambigua as new a source of minerals. The mineral concentrations of two different growing populations (natural occurrence and irrigated) of S. ambigua were evaluated using inductively coupled plasma mass spectrometry. In all samples, the mineral present in highest amounts was potassium (K) (19–24 μg g−1), followed by magnesium (Mg) (8.6–14 μg g−1) and then calcium (Ca) (2.6–4.0 μg g−1). In addition, in vitro bioacessibility assay demonstrated that very high fraction (65–80%) of these K and Mg (80 and 65%) of total concentration of these elements is bioacessible from S. ambigua analyzed. The trace elements vanadium (V), chromium (Cr), cobalt (Co), copper (Cu) and lithium (Li) have more than above 50% of total concentration was found bioaccessible. In all cases, mass balance was verified by carrying out the total digestion of the remaining residue and the relationship between total concentration and bioaccessibility. The data related to the concentrations and the bioaccessible fractions of the minerals provide a starting point for more complex and in-depth evaluations from the nutritional point of view, including the establishment of a recommended daily dietary intake for this plant.  相似文献   

3.
Rice and its derivatives are important source of essential and non-essential elements. Essential elements as cobalt (Co) and selenium (Se) are vital for human homeostasis. However, non-essential elements such as arsenic (As), cadmium (Cd) and lead (Pb) may be present in rice-based food and consequently, people can be exposed—especially children and the celiac population. This study aimed to determine essentials and non-essentials elements in rice-based products and baby food and also to evaluate nutritional risk by estimating the daily intake of non-essential elements. Regarding essential elements, Co and Se presented the highest concentrations in rice flour (56 μg kg−1) and porridge (254 μg kg−1), respectively. For non-essential elements, the highest concentrations of As, Cd and Pb were 104 μg kg−1 (porridge), 16 μg kg−1 (flour), and 188 μg kg−1 (bread), respectively. Total As concentration in Brazilian rice-based baby food was <29 μg kg−1. However, As-speciation revealed inorganic-As (i-As) as the main specie. The highest estimated daily intake of Cd, Pb and i-As were 1.37 (rice-based baby food); 10.39 (pasta); and 3.34 (pasta) μg d−1, respectively. Therefore, continuous food monitoring for nutritional and toxicological purpose is necessary, especially concerning these particular populations and discussions for maximum levels of non-essential elements.  相似文献   

4.
Different honey types were collected in Croatia during 2010 and 2011: 7 multifloral orchard honeys, 7 multifloral meadow honeys, 19 black locust, 9 chestnut, 11 lime and 6 sage honeys. Elements were measured using graphite (As, Cu, Cd, Pb, Se) and flame atomic absorption spectrometer (Ca, Fe, K, Mg, Na, Zn) and by mercury analyser (Hg). Significant differences in Ca, Fe, K, Mg, Zn, As and Hg levels were observed between honey types. In chestnut honey were determined (K, Ca, Mg: mg kg−1; Hg, Ad, Cd: μg kg−1): the highest concentrations of K 2824.4, Ca 486.7, Mg 59.1 and Hg 2.52; the lowest of As 24.1 and Cd 2.52. Lime honey has been shown the highest content of Cu (20.6 mg kg−1), Zn (6.78 mg kg−1), Cd (2.14 μg kg−1) and Pb (810.3 μg kg−1). The lowest levels of following elements were determined in black locust honey (Fe, K, Mg: mg kg−1; Hg: μg kg−1): Fe 2.77, K 304.7, Mg 8.02 and Hg 0.82. Sage honey had the lowest Ca and Na content (173.9 and 31.8 mg kg−1). Among the multifloral honeys, the following was determined (Fe, Na, Cu: mg kg−1; As, Pb: μg kg−1): orchard honey – highest of Fe 5.17 and As 276.1, lowest Pb 301; meadow honey – highest Na 36.1, lowest Cu 4.38. The average Ca, Cu and Pb levels found in multifloral honey types were much higher than those reported in other European countries. Calcium levels in lime, chestnut and black locust were higher than those from other countries.  相似文献   

5.
A single-run high performance liquid chromatography (HPLC) with diode array detector (DAD) based method was developed for the separation, identification and comprehensive quantification of degradation products of ergosterol formed in oyster mushroom (Pleurotus ostreatus) after UV-B exposure. After 60 min, 10 substances involved in the photoprocess were separated, identified by their characteristic DAD spectrum and distinguished by their molecular weight, in cases where spectra were identical: vitamin D2, previtamin D2, tachysterol2, lumisterol2 and ergosterol, and, in minor quantity, their structural analogues of the 22,23-dihydroergocalciferol (vitamin D4) series. Sample preparation protocol affected the total yields and the ratios of previtamin and vitamin D2/D4. Hot alkaline hydrolysis resulted in the best digestion of the mushroom matrix and accordingly gave the highest vitamin D yield (D2: 141.32 μg g−1 dry matter, DM; D4: 22.72 μg g−1 DM). Limit of detection for vitamin D2/4 was 0.02 μg g−1 dry matter (DM) and was estimated for previtamin D2/4 (0.06 μg g−1 DM), tachysterol2/4 (0.02 μg g−1 DM) and lumisterol2/4 (0.06 μg g−1 DM). Recovery of spiked vitamin D2 was 97 ± 0.7%. The study provides an analytical tool to assess the process of vitamin D generation after UV-B treatment for the production of oyster mushrooms with a balanced nutritional profile of vitamin D compounds.  相似文献   

6.
In this paper, microwave-accelerated dispersive liquid–liquid microextraction has been developed for the extraction/preconcentration of some organophosphorus pesticides from aqueous samples prior to their analysis by gas chromatography–flame ionization detection. In this method, temperature of a high volume of aqueous sample is elevated by a microwave oven and then a mixture of extraction and disperser solvents is rapidly injected into the aqueous phase. After cooling to room temperature, the phase separation is accelerated by centrifuging. The main experimental factors affecting performance of the method including type and volume of the extraction and disperser solvents, temperature, pH, and salt addition were investigated and optimized. Under the optimum extraction conditions, the method resulted in low limits of detection and quantification within the ranges of 0.65–1.3 and 2.2–4.5 μg L−1, respectively. Relative standard deviations were in the range of 2–7% (C = 40 or 100 μg L−1) for intra-day (n = 6) and inter-day (n = 4) precisions. Finally, the proposed method was successfully applied to analysis of the target analytes in surface water and well water and fruit juice samples; diazinon was determined at μg L−1 level in apple juice.  相似文献   

7.
In this study the concentrations of K, Ca, Mg, Na, Al, Zn, Fe, Mn, Cu, Cr, Ni, Se, Pb, Cd, and As in 39 honey samples of different botanical (orange-blossom, lemon-blossom, chestnut, eucalyptus, acacia, sulla and wildflower honeys) and geographical (Sicily and Calabria, Italy) origin were determined by ICP-OES and ICP-MS. The most abundant minerals decreased in the following order: K (mean value: 1.57 mg g−1) > Ca (0.2 mg g−1) > Mg (0.121 mg g−1) > Na (0.092 mg g−1). Recommended Dietary Allowance (RDA) values and benchmark levels were employed to assess the honey quality and safety. The data excluded toxicological risks: for an adult of 60 kg, a daily intake of 2 g of honey covered maximum 0.40% of Tolerable Weekly Intake (TWI) for Al, 0.33% of Benchmark Dose of 1% Extra Risk (BMDL01) for Pb, and 0.07% of Tolerable Daily Intake (TDI) for Ni. Mineral content marks the differences in honey samples from different geographical origin despite the botanical factor weight and can be used as a tool to assess the traceability of honeys. The discrimination between Sicilian and Calabrian honeys was achieved by Principal Component Analysis (PCA), and also the results of Canonical Discriminant Analysis (CDA) indicate that the 100% of total samples are correctly classified. This research contributes to the studies to determine the geographical origin of honeys.  相似文献   

8.
Total (Ast), inorganic arsenic (Asi = As(III) + As(V)) and dimethylarsonic acid (DMA) were determined in 37 commercial rice samples collected in France. Ast was measured by inductively coupled plasma-mass spectrometry (ICP-MS) whereas anion-exchange chromatography – ICP-MS was used for Asi and DMA determination. Ast in raw rice varied from 0.041 to 0.535 mg kg−1 whereas Asi varied from 0.025 mg kg−1 (polished Basmati rice) up to 0.471 mg kg−1 (organic rice duo). The daily intake and associated health risk for different population groups as a function of age and gender was also assessed. The intake varied between 0.002 and 0.184 μg kg−1 body weight for Ast and 0.002 and 0.153 μg kg−1 body weight for Asi, which do not pose a chronic toxicity risk. Organic wholegrain rice may entail a risk for children in the case of sole consumption at the expense of polished rice. The impact of rice cooking/boiling in terms of the overall toxicological risk related to As species was also investigated. Pre-rinsing and boiling the raw rice by using an excess of water is the most efficient mode to obtain a significant Asi removal and further reduction of the toxicological risk for children, particularly for white rice varieties.  相似文献   

9.
The aim of the study was to determine the content and profile of heterocyclic aromatic amines (HAAs) formed during the process of grilling beef under various conditions and involving different cuts of beef meat. 4,8-DiMeIQx was the most prevalent (4.50–7.55 ng g−1) the next were: MeIQx (1.10–7.20 ng g−1), MeIQ (1.70–5.30 ng g−1), and IQ (0.38 2.00 ng g−1). Changes in HAAs content, depending on the chemical composition of beef meat, were investigated; the compounds under analysis included free amino acids, glucose and protein as well as free nitrogenous bases and their nucleosides. It was demonstrated that HAAs formation strongly correlates with the presence of various amino acids in raw beef as well as that of glucose and protein (correlation coefficient 0.84–0.93). It was also demonstrated that free purine bases, pyrimidine bases and their nucleosides, which had never previously been studied in terms of their role as substrates for HAAs synthesis, correlate very strongly with HAA formation in grilled beef (correlation coefficient 0.78–0.99). The influence of thermal processing at high temperatures on the thermal decomposition of aminoimidazoazaarenes has not been corroborated by the present study.  相似文献   

10.
A slurry sampling flame atomic absorption spectrometric method is proposed for the determination of copper, manganese and iron in oysters (Crassostrea rhizophora), clams (Anomalocardia brasiliana) and mussels (Mytella guiyanensis; Perna perna). Optimization was carried out using univariate methodology involving the following variables: nature and concentration of the acid solution for slurry preparation, sonication time and sample mass. The optimized conditions were 80 mg of sample ground in a cryogenic mil, dilution using 1.0 mol L−1 nitric /hydrochloric acid solution, sonication time of 30 min and a slurry volume of 10 mL. The calibration curves had been prepared using standards of copper, manganese and iron also in 1.0 mol L−1 nitric/hydrochloric acid solution. This method allowed the determination of copper, manganese and iron by FAAS, with detection limits of 0.17, 0.09 and 0.46 μg g−1, respectively. The precision, expressed as relative standard deviation (RSD), are 3.0%, 2.9% and 3.8% (n=10), for concentrations of copper, manganese and iron of 17, 22 and 719 μg g−1, respectively. The accuracy of the method was confirmed by analysis of the certified oyster tissue (NIST 1566b). The proposed method was applied for the determination of copper, manganese and iron in samples of oyster, clams and mussels, collected in Ubatuba and Todos os Santos Bay, Brazil. The obtained concentrations varied between 17.1 and 143.9 μg g−1, 17.9 and 29.7 μg g−1 and 364 and 1388 μg g−1, respectively, for copper, manganese and iron. These values agree well with other data reported in the literature. The results showed no significant differences (P>0.005) using the proposed method with those obtained after complete digestion and determination by inductively coupled plasma-optical emission spectroscopy (ICP-OES).  相似文献   

11.
The aim of this work is to present a simple and sensitive reverse-phase liquid chromatography method for the determination and investigation of amino acids in wolfberry fruit (Lycium barbarum) after solid-phase extraction-derivatization. The method linearity, calculated for each amino acid, had a correlation coefficient higher than 0.9950, in concentrations ranged from 9.60 to 3.33 × 103 μmol L−1. The detection limits of amino acids were between 2.42 and 6.51 μmol L−1. The calculated recoveries for amino acids in wolfberry fruit were from 87.3% to 97.1% and relative standard deviations were from 2.62% to 5.22%. The investigation illustrated that each tested wolfberry fruit contained at least 16 amino acids and the main amino acids were glutamic acid, aspartic acid, proline, alanine, serine, glycine, lysine, and tyrosine. The levels of amino acid in wolfberry fruit were varying from different areas.  相似文献   

12.
A survey was conducted on the presence of hydroxymethylfurfural (HMF) and furfural in bread and bakery products; for this purpose a reliable extraction procedure followed by high performance liquid chromatography (HPLC) was applied. The performance of the method was evaluated in terms of linearity (r always > 0.99); detection limits (0.001 mg L−1 for furfural and 0.006 mg L−1 for HMF); recovery percentages (98.5–100.5% for HMF and 94.9–98.9% for furfural); intraday precision (<4.65%) and interday precision (<7.51%). Two batches of a wide variety of products commercially available were analysed (a total of 88 samples). HMF and furfural levels presented high variability between products and batches of the same product. Cake/pastry samples showed the lowest HMF content (3.0 mg kg−1 fw) while biscuits showed the highest content (7.8 mg kg−1 fw) (p < 0.05). Regarding furfural, bread samples presented the highest furfural content (5.3 mg kg−1 fw) (p < 0.05), cake/pastry and biscuits showed the lowest content (1.9 and 3.0 mg kg−1 fw, respectively). Chocolate containing samples presented higher amounts of furfural (>20 mg kg−1). These results indicate that special attention should be given to furfural content of bread (due to its daily high consumption) and re-evaluation of dietary exposure.  相似文献   

13.
The objective of this work was the evaluation of different conditions for the selected free amino acids extraction from cheese samples, followed by capillary isotachophoresis analysis. Parameters of the extraction: concentration and type of extraction reagents (solvents: methanol, ethanol and mineral acids: perchloric acid, trichloroacetic acid, sulphuric acid and hydrochloric acid), time and temperature, and isotachophoretic separation conditions (voltage, time) were studied. Repeatability, reproducibility and stability of this method at different conditions are discussed. The best yield of free amino acids was obtained after triple extraction (30 min each process) with 0.1 M hydrochloric acid at 50 °C. Histidine, lysine, arginine, ornithine, tyrosine, and phenylalanine were determined using calibration curves and the standard additions method in different types of cheeses. The highest level of amino acids was determined in semi-hard cheese (2626.3 mg 100 g−1 – calibration curve, and 2679.2 mg 100 g−1 – standard additions method), whereas the lowest were found in sheep cheese (426.3 mg 100 g−1 and 455.7 mg 100 g−1, respectively), and Gouda type cheese samples (441.5 mg 100 g−1 and 472.8 mg 100 g−1, respectively).  相似文献   

14.
Phenolic compound composition and antioxidant capacity of four Oenocarpus distichus Mart. (bacaba-de-leque) genotypes were determined. In order to set the parameters for phenolic compound extraction, the effect of methanol concentration and extraction time on the reducing power of the extracts was evaluated using the surface response methodology. The optimal conditions were: a 60:40 methanol:water (v/v) solution and 11 min of extraction. Extracts were analyzed by ultra-high performance liquid chromatography with diode array detection and by ultra-high performance liquid chromatography coupled to mass spectrometry. Eleven substances were identified, of which six were quantified. Rutin was the major compound in bacaba-de-leque genotypes (15.2–56.8 μg.g−1) followed by epicatechin (15.5–21.2 μg.g−1). The Black-03 genotype had the highest amounts of all phenolic compounds and the highest antioxidant capacity by DPPH and ORAC assays, indicating that this genotype may be selected in breeding programs to obtain cultivars with higher phenolic compound contents and antioxidant capacity. Moreover, the results indicated that bacaba-de-leque has great potential as a novel supplier of phenolic acids and flavonoids to human diet, with levels comparable to or higher than other fruits belonging to the same family, such as açaí.  相似文献   

15.
After the EU banned the use of the neonicotinoids in flowering crops that honeybees might visit, there has been an increased interest in determining the neonicotinoid residues in honeybee products such as honey. The aim of this study was to develop and optimize an HPLC-DAD analytical method with dispersive liquid–liquid microextraction (DLLME) and QuEChERS sample preparation procedures for the simultaneous analysis of seven neonicotinoids (dinotefuran, nitenpyram, thiametoxam, clothianidin, imidacloprid, acetamiprid and thiacloprid) in honey samples. The liquid chromatographic conditions were optimized by Response surface methodology with Box–Behnken design and Derringer's desirability. The optimized method was validated to fulfill the requirements of SANCO/12571/2013 standard for both sample pretreatment procedures providing results for accuracy (73.1–118.3%), repeatability (3.28–10.40%) and within-laboratory reproducibility (6.45–17.70%), limits of detection (1.5–2.5 μg kg−1) and quantification (5.0–10.0 μg kg−1) with the use of matrix-matched calibration to compensate the matrix effects. For the first time 104 honey samples from Vojvodina were analyzed. The presence of thiacloprid, imidacloprid and thiametoxam was found in a small number of samples implicating the usefulness of ongoing control of honey. Residues were confirmed by LC–MS/MS.  相似文献   

16.
Scattering signals and partial overlapping of target peaks usually appear in fluorescence determination. In this study, the improved wavelet moment method was proposed and applied to the quantitative determination of multiple target components in real B-vitamins complex tablets based on three-dimensional (3D) fluorescence spectra. The correlation coefficients (R) were more than 0.9939, and the correlation coefficients of leave-one-out cross-validation (RLOO-cv) were more than 0.9376. The inter-day and intra-day variations were less than 5.8% and 6.1%, respectively. The recovery ranged from 97.6% to 109.4%. The limits of detection (LODs) and quantification (LOQs) were less than 0.07 μg mL−1 and 0.13 μg mL−1, respectively. All the statistical parameters indicated that the method was stable and reliable. The application to the practical samples confirmed that wavelet moment method effectively extracted the features of target components in 3D spectra and the proposed method could be applied to the analyses of food or other complex samples.  相似文献   

17.
A sensitive, precise and reliable flow-batch method for the determination of aluminium (Al) was developed using a sequential injection-monosegmented flow system incorporating a mixing chamber unit. Eriochrome cyanine R (ECR) was used as a chromogenic reagent in the presence of N,N-dodecyltrimethylammonium bromide (DTAB). The Al-ECR complex at pH 6 gave a maximum absorption at 584 nm. In-line single standard calibration and a standard addition procedure were developed employing the monosegmented flow technique. Under the optimum conditions, a linear calibration graph in the range of 0.0075–0.625 mg L−1 Al was obtained with limits of detection and quantitation of 0.0020 and 0.0070 mg L−1, respectively. Relative standard deviations were 0.8 and 1.3% for 0.010 and 0.025 mg L−1 Al (n = 11), respectively. A sample throughput of 24 h−1 using an in-line standard calibration approach and 6 h−1 using four standard addition levels was achieved. The developed system was successfully applied to water samples and beverage samples. The results agreed well with those obtained from the ICP-AES method. Good recoveries between 85 and 104% were obtained.  相似文献   

18.
Proximate composition, unsaponifiable lipid components (cholesterol, squalene, tocopherols, all-trans retinol, total carotenoids) and fatty acid profile were evaluated on red mullet (Mullus barbatus) caught in the Central Tyrrhenian and Central Adriatic seas (Italy). The study was conducted in spring, the reproduction period, and in autumn, the period of maximum recruitment and market demand for this species. Results showed that, in fish from both sites, protein (18.1–18.8 g 100 g−1), nonprotein nitrogen (0.32–0.35 g 100 g−1), ash (1.27–1.42 g 100 g−1) and cholesterol (56.8–73.7 mg 100 g−1) contents were almost stable. Total lipid levels were highly variable, with very low levels in spring (0.96–1.48 g 100 g−1) and high levels in autumn (7.28–8.72 g 100 g−1). On a total fatty acids basis, polyunsaturated fatty acids (PUFA) were significantly higher in spring (30–40% of total fatty acids), when fish was lean, than in autumn (20%), while monounsaturated fatty acids were significantly higher in autumn (35–38%) than in spring (18–29%). Saturated fatty acids were almost stable throughout the year (34–39% of total fatty acids). Red mullet from the two sites showed a good nutritional value; in particular they proved to be a good source of n-3 PUFA, which accounted for 75–80% of total PUFA, regardless of the fishing season. However, it was in autumn that red mullet exhibited the highest content of n-3 PUFA (>1000 mg 100 g−1 wet fillet). The comparison of samples by geographical origin showed no difference in autumn, while slight differences were observed in spring.  相似文献   

19.
Red- and purple-fleshed potatoes (Solanum tuberosum L.) are a good source of polyphenols, mainly anthocyanins as one of the most important components. The chemical composition with reducing sugars and the total polyphenol contents were analyzed in four purple potato varieties (Salad Blue, Vitelotte, Valfi, Blue Congo) and three red-fleshed potato varieties (Rosalinde, Herbie 26, Highland Burgundy Red). The anthocyanin composition of raw potato and potato crisps was characterized by high-performance liquid chromatography tandem mass spectrometry (HPLC–MS/MS) method. Moreover, the antioxidant activity was measured with the radical scavenging assays using 2,2′-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical as well as ferric reducing ability of plasma assay (FRAP). In addition, colour parameters in prepared potato crisps were evaluated. Both red and purple-fleshed potato varieties contained high levels of total polyphenols (227–845 mg 100 g−1 dry weight) and anthocyanins (21–109 mg 100 g−1 dry weight). The process of frying caused degradation of anthocyanin compounds (38–70%). The HPLC–MS/MS analysis showed that pelargonidin and malvidin derivates were more stable during frying than petunidin derivatives. Although frying process affected the anthocyanin and polyphenol levels, obtained potato crisps exhibited bright intensive colour and good antioxidant activity.  相似文献   

20.
Polycyclic aromatic hydrocarbons (PAH) in traditional/industrial smoked and unsmoked Circassian cheeses available in Turkish markets were analysed using solid-phase extraction, followed by high-performance liquid chromatography (HPLC) with fluorescence detection. Mean levels of a total of 9 PAHs in smoked traditional and industrial Circassian cheeses were 19.6 and 6.73 μg kg−1, while levels in unsmoked traditional and industrial cheeses were 0.77 and 0.49 μg kg−1, respectively. The dominant individual PAHs found were naphthalene and acenaphthene. Benzo[a]pyrene, a marker compound representing carcinogenic PAHs, was found in 90% and 30% of traditional smoked and unsmoked Circassian cheeses, 52% and 24% of industrial smoked and unsmoked cheeses, respectively. Correlation statistical analysis showed that benzo[a]pyrene was a good marker for total 9 PAHs in Circassian cheese samples (rB[a]P/sum of 9 PAHs = 0.816, p < 0.01) as well as the best marker for 5 carcinogenic PAHs (rB[a]P/carcinogenic PAHs = 0.904, p < 0.01). Risk assessment conducted using daily intakes of sum of 9 PAH levels found in both traditional and industrial smoked Circassian cheese samples showed high risk compared with unsmoked cheeses.  相似文献   

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