In-house validation of a method for determining aflatoxins B1, B2, G1 and G2 in wheat and wheat by-products

Aflatoxins are naturally occurring carcinogenic substances, extremely toxic to humans, which have been identified in wheat and wheat by-products. The use of reliable analytical methods to evaluate and monitor such contaminants is extremely important. This study aimed to in-house validate a methodology to determine aflatoxins B1, B2, G1 and G2 in wheat grains using pre-column derivatization and quantification by High Performance Liquid Chromatography with fluorescence detection (HPLC-FLD). Three methods were evaluated and the most suitable one was the method based on the extraction with chloroform, removal of interfering chemicals by filtration, liquid-liquid partition with hexane-methanol-water and methanol-water-chloroform and pre-column derivatization with trifluoroacetic acid. The method showed a Relative Standard Deviation lower than 15% and recovery values in the 70-110% range, with limits of detection and quantification (0.6 µg kg-1 and 1.2 µg kg-1, respectively) below the maximum level of aflatoxins allowed in wheat and wheat by-products by the European Commission (4.0 µg kg-1) and by the Brazilian legislation (5.0 µg kg-1). Using the validated method, aflatoxins were quantified in 20 commercial samples of wheat grains, wheat bran, whole wheat flour and refined wheat flour intended for direct human consumption. Six samples (30%) were positive for aflatoxins and all samples presented levels below the maximum limit stipulated by the Brazilian legislation.

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Proximate composition and quantitative analysis of benzoyl peroxide and benzoic acid in the wheat flour samples: wheat flour quality

10.7287/peerj.preprints.27969 ◽

2019 ◽

Author(s):

Numrah Nisar ◽

Faiza Mustafa ◽

Arifa Tahira ◽

Rashad Waseem Khan Qadri ◽

Yaodong Yang ◽

...

Keyword(s):

High Performance Liquid Chromatography ◽

Liquid Chromatography ◽

Benzoic Acid ◽

Benzoyl Peroxide ◽

Wheat Flour ◽

Proximate Composition ◽

High Performance ◽

Wheat Crop ◽

Whole Wheat Flour ◽

Whole Wheat

Background. Extensive milling processes have deprived wheat flour from essential nutrients. Objective of the current study was to assess the nutritive quality of commercial wheat flour (soft flour/SF) through analyses of proximate composition and functional properties as well as quantification of benzoyl peroxide (BP; added as bleaching agent in the SF). Methods. Test samples included commercial soft flour samples purchased from the local supplier from different flour mills (with additives) and a control sample without additives was prepared by grinding the seeds harvested from wheat crop grown in the experimental field of University of Agriculture, Faisalabad, under optimized field conditions without any fertilizer and insecticide. Benzoyl peroxide and Benzoic Acid quantification was performed through High Performance Liquid Chromatography Results. Results when compared with the whole wheat flour (WF; never received additives) indicated that SF had lesser fiber, protein and ash contents, whereas, higher damaged starch, fat, gluten and bulk density. A parallel experiment under selected conditions (temperature, time and solute concentration) showed dissociation of BP into BA soon after the exposure. Observed BA range (13.77 mg/g after 16hrs) in SF and exposure level assessment (44.3±1.36 mg/kg/BW) showed higher intake of BA on the consumption of SF. Results revealed superiority of WF over SF in nutritive qualities as well as free of toxicants such as BA. KEYWORDS: Benzoyl peroxide; Benzoic acid; Soft Flour; Whole Wheat Flour; High Performance Liquid Chromatography

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Protein-rich mixtures for human consumption based on fish flour, sunflower presscake meal, dried skim milk and wheat flour

British Journal Of Nutrition ◽

10.1079/bjn19680031 ◽

1968 ◽

Vol 22 (2) ◽

pp. 255-259 ◽

Cited By ~ 3

Author(s):

Digna Ballester ◽

ITA Barja ◽

E. Yáñez ◽

G. Donoso

Keyword(s):

Wheat Flour ◽

Skim Milk ◽

Human Consumption ◽

Protein Utilization ◽

Whole Wheat ◽

Triticum Sativum ◽

Protein Rich ◽

Net Protein ◽

Rich Mixtures

1. The quality of the protein in five high-protein mixtures intended for human consumption and made from materials that are available in Chile is reported.2. The ingredients were fish flour, bread, wheat (Triticum sativum Lam.) flour, roasted whole wheat flour, a wheat flour made from a variety of durum wheat (T. durum Desf.), skim milk and sunflower presscake, mixed in different proportions.3. The net protein utilization when fed to rats in diets at the 10% level of protein calories gave values in the range 66–76, which compare well with that (67), found for Incaparina, an all-vegetable mixture produced by the INCAP Group and used in Colombia, and are higher than the values (55 and 56) obtained for Peruvitas, which are mixtures made up basically from cottonseed and quinoa reinforced with dried skim milk.4. The protein values of the mixtures, expressed as net dietary protein calories %, were calculated from their biologically determined net protein utilization (operative), and gave values that ranged from 10·5 to 12·8, which are higher than the recommended values in diets for infants and toddlers.

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AVALIAÇÃO DA PRESENÇA DE PESTICIDAS N-METILCARBAMATOS E SEUS PRODUTOS DE DEGRADAÇÃO NAS ÁGUAS DA REGIÃO DE PARÁ DE MINAS (MG) BRASIL

Pesticidas Revista de Ecotoxicologia e Meio Ambiente ◽

10.5380/pes.v11i0.3137 ◽

2001 ◽

Vol 11 ◽

Author(s):

FABRÍCIO VILELA PARREIRA ◽

EUCLER B. PANIAGO ◽

CIOMARA RABELO DE CARVALHO ◽

ROBSON JOSÉ DE CÁSSIA FRANCO AFONSO

Keyword(s):

Water Samples ◽

High Performance ◽

Solid Phase ◽

Degradation Products ◽

Phase Extraction ◽

Method Detection Limit ◽

Ultraviolet Detector ◽

Brazilian Legislation ◽

Relative Standard ◽

The City

Os pesticidas N-metilcarbamatos e alguns de seus metabólitos são altamente tóxicos para o homem e o meio ambiente. Por esta razão desenvolveu-se método analítico utilizando extração em fase sólida e cromatografia líquida de alta eficiência com detector de ultravioleta (CLAE/UV) para análise destes compostos em amostras de água. O método apresentou índice de recuperação para 10 compostos de 57 a 99%, com desvio padrão relativo (CV) de 5,67 a 7,67% para n=6. A repetitividade do método forneceu CV entre 5,94 a 8,46% para n=6. O limite de detecção do método (MDL) situou-se na faixa de 0,07 a 0,38 µg/L para 10 compostos. Este método foi aplicado na análise de amostras de águas coletadas na cidade de Pará de Minas-MG, Brasil, e também em alguns pontos selecionados nas bacias dos Rios Paciência e Bom Sucesso, situadas no município de Pará de Minas. Os resultados das análises em amostras de água mostraram-se abaixo dos limites estabelecidos pela legislação brasileira. EVALUATION OF THE PRESENCE OF N-METHYLCARBAMATE PESTICIDES AND DEGRADATION PRODUCTS IN WATERS OF PARÁ DE MINAS (MG) REGION IN BRAZIL Abstract The N-methylcarbamate pesticides and some of the their metabolites are highly toxic for men and environment. Then, an analytical method utilizing solid phase extraction and high performance liquid chromatography with ultraviolet detector (SPE/CLAE/UV) to analyze these compounds in water was developed. The accuracy of the method for 10 compounds varied from 57 to 99%, presenting relative standard deviation (RSD) from 5,67 to 7,67% for n=6. The repeatability supplied RSD among 5,94 to 8,46% for n=6. The method detection limit (MDL) is in the ranging of 0,07 to 0,38 µg/L for 10 compounds. This method was utilized in water samples collected in the city of Pará de Minas (MG) and in several points of the rivers Paciência e Bom Sucesso, situated in Pará de Minas (MG), Brazil. The results of the analysis of water samples are bellow of the limits permitted by Brazilian legislation.

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Ochratoxin A contamination of cereal grains and coffee in Hungary in the year 2001

Acta Veterinaria Hungarica ◽

10.1556/avet.50.2002.2.7 ◽

2002 ◽

Vol 50 (2) ◽

pp. 177-188 ◽

Cited By ~ 31

Author(s):

B. Fazekas ◽

A. K. Tar ◽

Melinda Zomborszky-Kovács

Keyword(s):

Ochratoxin A ◽

Wheat Flour ◽

High Performance ◽

Limit Of Detection ◽

Storage Period ◽

Storage Conditions ◽

Cereal Grains ◽

Animal Origin ◽

Human Consumption ◽

High Prevalence

Ochratoxin A (OTA) is a nephrotoxic and carcinogenic mycotoxin, a secondary metabolite produced by mould fungi belonging to several Aspergillus and Penicillium species. It is formed during the storage of cereal grains and other plant-derived products. OTA ingested by humans and animals with the food or feed may exert deleterious effects on health. The purpose of this study was to investigate the ochratoxin contamination of the most important potential sources of OTA. The OTA content of cereal samples for human consumption (36 baking wheat, 16 wheat flour and 6 maize coarse meal samples) and feed grain samples (30 feeding wheat, 32 feeding maize and 20 feeding barley samples) collected in the mid-phase or at the end of the storage period and of 50 commercial coffee samples was determined. The analyses were performed by immunoaffinity column - high-performance liquid chromatography (IAC-HPLC). The limit of detection of the method was 0.1 ng/g. Of the wheat samples intended for human consumption, 8.3% contained OTA at 0.29 ng/g on the average (OTA ranges: 0.12-0.5 ng/g; Table 2). The OTA contamination of wheat flour and maize meal samples for human consumption was similar to that of the baking wheat samples. OTA contamination was found in 26.7% of the feeding wheat, 15.6% of the feeding maize and 35% of the feeding barley samples. The average values and the ranges of OTA levels found in the above samples were 12.2 and 0.3-62.8 ng/g, 4.9 and 1.9-8.3 ng/g, and 72 and 0.14-212 ng/g, respectively (Table 3). Sixty-six percent of the coffee samples were contaminated with OA (average level: 0.57 ng/g, ranges: 0.17-1.3 ng/g; Table 4). OTA contamination of baking wheat samples was found to be relatively low, presumably as a result of the favourable weather at harvest and the optimal storage conditions. Calculations made on the basis of the obtained results show that the daily OTA intake of an adult human from edible cereals is only 6.7 ng, while the amount taken up with coffee is 4.1 ng daily. The high prevalence and high levels of OTA contamination in feed grains can be explained by the unfavourable storage conditions, and this finding suggests that OA-related health problems may arise in animals, and that foods of animal origin may be contaminated with this mycotoxin.

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Determination of Deoxynivalenol in Whole Wheat Flour and Whear Bran

Journal of AOAC International ◽

10.1093/jaoac/85.6.1355 ◽

2002 ◽

Vol 85 (6) ◽

pp. 1355-1359 ◽

Cited By ~ 4

Author(s):

Heidi S Rupp

Keyword(s):

Wheat Flour ◽

Wheat Bran ◽

Mobile Phase ◽

Limit Of Detection ◽

Test Sample ◽

Whole Wheat Flour ◽

Whole Wheat ◽

Relative Standard ◽

Liquid Chromatographic

Abstract A liquid chromatographic (LC) method was developed for determining deoxynivalenol (DON) in whole wheat flour and wheat bran. A 15 g test sample was extracted with acetonitrile–water (84 + 16, v/v) and applied to a Romer MycoSep cleanup column. The eluate was dried and then reconstituted in a 0.1M phosphate buffer, pH 7.0, and applied to a Vicam DONtest-LC cleanup column. The methanol eluate was chromatographed with a methanol–water (17 + 83, v/v) mobile phase on a C18 column with UV detection at 220 nm. Five replicates at each of 5 fortification levels (0.25, 0.50, 1.0, 2.0, and 4.0 ppm), plus 5 controls, were determined for both whole wheat flour and wheat bran. For flour, the average recoveries were 72.2–91.5% with relative standard deviations (RSDs) of 4.9–18.4%. The intra-assay flour recovery was 82.4% with 9.8% RSD. A 5 replicate sample of naturally incurred wheat had an average of 1.1 ppm DON with 6.7% RSD. For bran, average recoveries of fortified samples were 69.5–99.7% with RSDs of 1.7–18.8%. The intra-assay bran recovery was 81.5% with 8.9% RSD. The limit of detection (about 3× noise) for the method is 0.05 ppm; the correlation coefficient (linearity) was >0.9995. The DON peak was clearly identified and easily integrated in the chromatograms.

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Determination of Deoxynivalenol in White Flour, Whole Wheat Flour, and Bran by Solid-Phase Extraction/Liquid Chromatography: Interlaboratory Study

Journal of AOAC International ◽

10.1093/jaoac/81.4.880 ◽

1998 ◽

Vol 81 (4) ◽

pp. 880-886 ◽

Cited By ~ 25

Author(s):

Mary W Trucksess ◽

Samuel W Page ◽

Garnett E Wood ◽

Tae-Hee Cho

Keyword(s):

Solid Phase Extraction ◽

Wheat Flour ◽

Solid Phase ◽

Interlaboratory Study ◽

Phase Extraction ◽

Whole Wheat Flour ◽

Whole Wheat ◽

White Flour ◽

Relative Standard ◽

Standard Deviations

Abstract A liquid chromatographic (LC) method for determining deoxynivalenol (DON) in white flour, whole wheat flour, and bran at or above the U.S. Food and Drug Administration advisory level of 1 μg/g was evaluated by an interlaboratory study. Test samples of processed wheat (flour and bran) were extracted by blending with acetonitrile-water (84 + 16). Extracts were filtered and passed through a solid-phase extraction (SPE) column. The eluate was then chromatographed on a reversed-phase LC column with a water-methanol gradient. DON was measured at 220 nm. Naturally contaminated white flour, whole wheat flour, and bran samples and spiking solutions of DON to be added to the 3 commodities at 0.5,1.0, and 2.0 μg/g were sent to 4 collaborators in Kansas, Louisiana, Missouri, and Washington states. Three collaborators completed the study. Average recoveries of DON from the 3 commodities spiked at 0.5, 1.0, and 2.0 (μg/g were 94, 87, and 97%, respectively. Within-laboratory relative standard deviations for repeatability (RSDr) ranged from 3.1 to 21.7% and between-laboratory relative standard deviations for reproducibility (RSDR) ranged from 10.8 to 38.7%. On the basis of the results of this study, the SPE/LC method for DON in white flour, whole wheat flour, and bran was adopted as a peer-verified method by AOAC INTERNATIONAL

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Deoxynivalenol content, phenolic compounds, and antioxidant activity of wheat flour after debranning process

Pesquisa Agropecuária Brasileira ◽

10.1590/s1678-3921.pab2020.v55.01851 ◽

2020 ◽

Vol 55 ◽

Author(s):

Casiane Salete Tibola ◽

Milena Ramos Vaz Fontes ◽

Martha Zavariz de Miranda ◽

Rafaela Julyana Barboza Devos ◽

Alvaro Renato Guerra Dias ◽

...

Keyword(s):

Antioxidant Activity ◽

Triticum Aestivum ◽

Phenolic Compounds ◽

Antioxidant Capacity ◽

Phenolic Compound ◽

Wheat Flour ◽

Wheat Grains ◽

Whole Wheat ◽

Wheat Products ◽

Wheat Flours

Abstract: The objective of this work was to evaluate the effect of the debranning process on the deoxynivalenol (DON) content, phenolic compounds, and antioxidant activity of wheat flours, in order to determine which milling technology provides the safest and most nutritional wheat products. Grain samples from the BRS Marcante, BRS Reponte, and BRS 374 wheat (Triticum aestivum) cultivars were used to obtain both whole-wheat and white flours. For whole-wheat, grains were debranned at different times (20 and 40 s). The debranning process significantly reduced the DON content in the whole-wheat flours from all cultivars. The DON concentration decreased 22 and 28% in the 20 and 40 s debranning treatments, respectively, when compared with the treatment without debranning. In addition, phenolic compound content and antioxidant capacity are significantly higher in the whole-wheat flours. The debranning process contributes to the production of safer and healthier foods, by reducing DON content and retaining phenolic compounds and antioxidant activity in whole-wheat flours.

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XYLOOLIGOSACCHARIDES FROM AGRICULTURAL BY-PRODUCTS: CHARACTERISATION, PRODUCTION AND PHYSIOLOGICAL EFFECTS

Food Science and Technology ◽

10.15673/fst.v11i3.606 ◽

2017 ◽

Vol 11 (3) ◽

Cited By ~ 5

Author(s):

L. Kaprelyants ◽

O. Zhurlova ◽

T. Shpyrko ◽

L. Pozhitkova

Keyword(s):

High Performance ◽

Hydrolytic Degradation ◽

Pharmaceutical Preparations ◽

Size Exclusion ◽

Human Consumption ◽

Physiological Properties ◽

High Cholesterol Level ◽

Wide Range ◽

The Rich ◽

By Products

The current study is a review of characteristics, production, physiological properties and application of xylooligosaccharides (XOS). XOS are the carbohydrates, their molecules are built from xylose residues linked mainly by в-(1→4)-glycoside bonds. Xylan is important for plant cell walls and is widely spread component in agricultural by-products. XOS are products of xylan hydrolytic degradation, and exhibiting the high prebiotic potential. The XOS preparation of wheat and rye bran stimulated the cells accumulation ‑ 1,4∙1010 CFU/cm3 of L. аcidophilus and 9,2∙1010 CFU/cm3 of В. bifidum. A difference in XOS molecules branching causes a wide range of their physiological properties: antioxidant, immunomodulation, antimicrobial, anti-inflammatory, anticarcinogenic. XOS can reduce high cholesterol level and triglycerides in blood plasma. XOS application reviewed in this article opens new perspectives on its potential use for human consumption. The rich sources of xylan are wheat, rye and barley bran, rice husk, wheat straw, corncobs, cotton stalk. Industrial way of XOS production includes chemical or enzymatic hydrolysis with following purification. Chemical methods are based on hydrothermal pretreatment and acidic or alkali extraction. Obtained oligosaccharides have a wide range of polymerization degree (DP) from 2 to 20. Enzymatic methods include fermentation with xylanase that allow controlling the XOS accumulation with certain DP. The different chromatographic purification after hydrolysis is used for analytical purposes. There are anion-exchange, size-exclusion, affinity, size-exclusion high-performance liquid chromatography. In addition, biomethods are preferred for XOS used in food, because such preparations do not contain monosaccharides and furfural as contaminants. XOS are stable in a wide range of temperature and pH, justifying the development of new synbiotics generation. Most widely XOS are used in production of functional products and pharmaceutical preparations. But they are also applied in cosmetic, agricultural and mixed feed industries.

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Residue Analysis of Insecticides in Potatoes by QuEChERS-dSPE/UHPLC-PDA

Foods ◽

10.3390/foods9081000 ◽

2020 ◽

Vol 9 (8) ◽

pp. 1000

Author(s):

Débora Reis ◽

Pedro Silva ◽

Rosa Perestrelo ◽

José S. Câmara

Keyword(s):

High Performance ◽

Solid Phase ◽

Residue Analysis ◽

Array Detector ◽

Human Consumption ◽

Main Concern ◽

Solvent Ratio ◽

The European Union ◽

Insecticide Residues ◽

Relative Standard

Insecticides are broadly applied in agriculture to defend crops from illnesses and pest attacks, consequently guaranteeing high production. However, their residual deposits in food products are becoming a main concern with regard to human consumption. As such, sensitive analytical methods should be developed to assess, prevent and control insecticide residues. In this research, an accurate, fast and reliable residual analytical method, that is quick, easy, cheap, effective, rugged and safe, combined with dispersive solid phase extraction (QuEChERS-dSPE), was developed for the determination of the most common insecticides used in potatoes cultivation (chlorpyrifos, λ-cyhalothrin, deltamethrin and acrinathrin), using an ultra-high performance chromatography photodiode array detector (UHPLC-PDA). The most influential extraction and instrumentation parameters that affect the method’s performance, such as extraction solvent, ratio salts, sorbents, stationary phases, gradient conditions and eluents, were assessed. Under the ideal conditions, good linearity (0.992–0.998), limits of detection (0.02–0.47 µg/kg) and quantification (0.06–1.58 µg/kg), recovery (94.1 to 112%) and precision (relative standard deviation <18%) were achieved for spiked levels between 2.5 and 50 µg/kg. The obtained results revealed that the potatoes analyzed do not represent any concern for human healthy, as the insecticide residues detected were lower than the maximum residue limits set by the European Union, Codex Alimentarius, and other organizations.

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