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1.
The aim of this study was to conduct a survey assessing (a) the ochratoxin A (OTA) content in different samples of Astragalus propinquus root (AR), one of the fundamental herbs in traditional Chinese medicine, and (b) the rate of OTA transfer to AR decoctions that are traditionally used to reduce general weakness and increase overall vitality. A validated method of high-performance liquid chromatography with fluorescence detection (HPLC-FLD) was used to determine OTA concentrations in AR samples and AR decoctions. The limit of quantification was 0.35 ng/g; the recovery of the HPLC method for AR samples was 82%; and the relative standard deviation (SD) of repeatability was 2.6%. All 40 tested AR samples were positive, with a mean value of 451.0 ng/g (range, 28.8–1700.0 ng/g). The transfer rate of OTA to decoctions, from a naturally contaminated and homogenized AR sample (internal reference material) with a concentration of OTA of 288.9 ng/g?±?12.3 (SD), was 83.4%?±?8.5 (SD). We believe it is necessary to continue OTA monitoring in AR and other herbal products, estimate the actual human usual intake, and perform health risk assessment.  相似文献   

2.
The mycotoxin ochratoxin A (OTA) and its metabolite ochratoxin alpha (OTα) were determined in milk and blood from nine lactating women who provided samples soon after delivery at a hospital in southern Chile. The analytical method applied liquid–liquid extraction with chloroform, and in the case of blood, an extra purification with solid phase extraction prior to HPLC analysis with fluorescence detection. OTA was detected in all human milk samples, with an average concentration of 106?±?45 ng/L (range 44–184 ng/L). Levels of OTα were 40?±?30 ng/L (LOQ 40 ng/L), but increased considerably upon enzymatic hydrolysis with ß-glucuronidase/sulfatase (up to 840?±?256 ng/L) in human milk. By contrast, there was no evidence for conjugates of OTA. The data on OTA in breast milk and levels reported in blood from women in Chile are indicative of an efficient lactational transfer of the mycotoxin. Infant exposure to OTA was estimated by considering their daily OTA intake with human milk at early stages of nursing. For the majority of milk samples, the calculated OTA intake of infants exceeded the tolerable daily intake (TDI) of 5 ng/kg body weight (bw)/day proposed by the Nordic Expert Group, and infant exposure approached the provisional tolerable doses of 14–16 ng/kg bw/day suggested by the Joint FAO/WHO Expert Committee on Food Additives (JEFCA) and by EFSA for adults. The present study documents and confirms the presence of OTA in human milk at levels where the TDI can be exceeded. These results point out the need to continue food and biological monitoring and to develop strategies, e.g. dietary recommendations to pregnant and lactating women, aimed to reduce OTA exposure in early periods of life.  相似文献   

3.
Eighty-five samples of cocoa products sampled in Canada were analysed for ochratoxin A (OTA) and aflatoxins in 2011–2012. Inclusion of the aflatoxins in this survey required additional method development. Chocolate was extracted with methanol–water plus NaCl, while for cocoa two successive extractions with methanol and methanol–water were made. Extracts were cleaned on an AflaOchra immunoaffinity column (IAC). Determination was by reversed phase high performance liquid chromatography (HPLC). Detection of the aflatoxins was with a post-column photochemical reactor and of OTA by fluorescence detection. Mean limits of quantification (LOQ) of chocolate and cocoa powders were 0.16 ng/g (OTA) and 0.07 ng/g (aflatoxin B1), respectively. Survey results showed that the incidences of OTA above the LOQ in natural cocoa were 15/15 (mean 1.17 ng/g), 20/21 for alkalized cocoa (mean 1.06 ng/g), 9/9 for baking chocolate (mean 0.49 ng/g), 20/20 for dark chocolate (mean 0.39 ng/g), 7/10 for milk chocolate (mean 0.19 ng/g), 5/5 for cocoa liquor (mean 0.43 ng/g), and 0/5 for cocoa butter. These results confirm our previous work with OTA. In the same samples, incidences of aflatoxin B1 above the LOQ were 14/15 for natural cocoa (mean 0.86 ng/g), 20/21 for alkalized cocoa (mean 0.37 ng/g), 7/9 for baking chocolate (mean 0.22 ng/g), 16/20 for dark chocolate (mean 0.19 ng/g), 7/10 for milk chocolate (mean 0.09 ng/g), 4/5 for cocoa liquor (mean 0.43 ng/g), and 0/5 for cocoa butter. Both aflatoxins and OTA were confirmed by HPLC-MS/MS when OTA or aflatoxin levels found were above 2 ng/g in cocoa.  相似文献   

4.
A total of 681 samples of spices, which comprised more than 50 different spice commodities were analysed for the natural occurrence of the mycotoxins ochratoxin A (OTA) and ochratoxin B (OTB). The analytical method involved chloroform extraction, clean-up by immunoaffinity column and HPLC determination of both mycotoxins. OTA and OTB were detected in 143 (21%) and 68 (10%) of the samples, respectively. The highest frequency of occurrence of both mycotoxins detected were in chili (100% for OTA and 55% for OTB), paprika (41% and 15%, respectively) and pepper (23% and 44%, respectively). The toxin concentrations ranged between the detection limit (0.01 ng/g) and 41.8 ng OTA (2.7 ng OTB)/g of chili, 18.9 ng OTA (1.4 ng OTB)/g of paprika and 3.8 ng OTA (4.6 ng OTB)/g of pepper. One sample of a extract of vanilla was found to be positive for OTB at 15 ng/g. However, median values of most samples showed to be below the detection limit. Comparison of the geographical origin of the samples showed that the predominant number of contaminated spices was from Southeast-Asia and India. Highly contaminated paprika samples were found to come from Israel.  相似文献   

5.
Ochratoxin A (OTA) is a mycotoxin produced mostly by several species of Aspergillus and Penicillium. OTA is nephrotoxic in all animal species in which it has been tested and is cancerogenic in rodents. It is associated with Balkan endemic nephropathy. It is naturally present in many crop products such as cereals (barley, wheat, maize) and dried fruits, spices, coffee, wine, olives, and cocoa. The aim of this study was to assess the contamination of three Ivoirian spices with OTA (ginger, chili, and pepper) widely consumed by the population. A total of 90 spice samples (ginger: n?=?30; chili: n?=?30; pepper n?=?30) was taken from various sales outlets of Abidjan. OTA was quantified using an HPLC apparatus coupled with a fluorimetric detector. The chili and ginger samples were contaminated with OTA at a mean concentration of 57.48?±?174 and 0.12?±?0.15 μg/kg, respectively. No contamination of the pepper samples was detected. Eight (26.67 %) of the chili samples exceeded the maximum limit of 15 μg/kg established by European regulation. These results should serve as an alert on the risk to the consumer population of these products that are highly contaminated with OTA.  相似文献   

6.
Ochratoxin A (OTA) was analyzed in human serum and kidney samples, collected in Poland in the Pomeranian region from March to September 2005. OTA was determined using reversed phase liquid chromatography with fluorescence detection. The collected samples were from patients after nephrectomy (9 from men and 11 from women) and control serum samples from people without kidney diseases (3 and 3, respectively). The mean concentration OTA in serum of the healthy group was 0.37 ng/ml in both men and women. In patients subjected to nephrectomy it reached 1.06 ng/ml in men and 0.94 ng/ml in women, the mean content of ochratoxin A in kidneys was 0.23 ng/g and 0.20 ng/g, respectively. The highest concentration of OTA in serum among the patients subjected to nephrectomy was 3.77 ng/ml in men and 2.27 ng/ml in women while in kidneys 0.45 ng/g and 0.39 ng/g, respectively. Presented at the 28th Mykotoxin-Workshop, Bydgoszcz, Poland, May 29–31, 2006  相似文献   

7.
Brewer’s yeasts are rich in vitamins of the B-group and contain other nutritive factors; therefore, they are recommended as valuable food supplements for people with special dietary requirements like pregnant women, children, and adolescents, or for people with high physical activity. Additionally, certain strains of brewer’s yeast are known to be capable of adsorbing xenobiotics such as mycotoxins. Because of that, these yeasts are regarded as having positive effects in food, beverage, and feed technology. Their potential to bind mycotoxins such as ochratoxin A (OTA), however, can subsequently lead to a contamination of such brewer’s yeasts used as food supplements. In the present study, we analyzed 46 samples of brewer’s yeasts for the occurrence of OTA by HPLC with fluorescence detector (HPLC-FLD) and for confirmatory measurements by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Nearly 90 % of the samples were contaminated with OTA, the levels ranging from the limit of detection (LOD, 0.01 μg/kg) to 4.2 μg/kg. The mean and median levels of contamination were 0.49 and 0.27 μg/kg, respectively. Based on these results, the additional weekly OTA exposure by regularly consuming such supplements was assessed. Depending on different subpopulations (adults, children) and levels of contamination used for calculation, the additional OTA intake via brewer’s yeast products ranged from 9.3 % (mean case) to 114 % (worst case) of the published mean weekly OTA intake in Germany (adults 279.3 ng, children 195.3 ng). At present, maximum levels for OTA in nutritional supplements like brewer’s yeast do not exist. Based on our results, however, it is recommended that producers of these dietary supplements should include mycotoxin analyses in ongoing and future self-monitoring programs and in product quality checks.  相似文献   

8.
The accuracy and precision of a commercially available system based on an indirect competitive immunoassay and planar waveguide technology was evaluated for the analysis of deoxynivalenol (DON), ochratoxin A (OTA), zearalenone (ZEAR), and T-2 toxin in wheat. The system generally performed well at the tested concentrations that were close to the regulatory limits of DON and OTA in wheat. The mean percent recovery of OTA from certified and in-house reference materials ranged from 90 to 111 %, with a relative standard deviation of 8–16 % (at 4.2, 4.9, and 7.0 μg/kg). Mean percent recoveries of DON ranged from 75 to 103 %, with a relative standard deviation of 14–20 % (at 610, 940, and 1300 μg/kg). As analyte concentrations approached the lower limits of the working range of 3 μg/kg OTA and 400 μg/kg DON, the mean percent recoveries and relative standard deviation increased for both DON and OTA. A lack of reference materials precluded a thorough evaluation of the method for the analysis of ZEAR and T-2. The particular strength of the technology was that multiple mycotoxins were analyzed simultaneously.  相似文献   

9.
The aim of this study was to compare ochratoxin A (OTA) levels in pig tissues and biological fluids after animal exposure to contaminated diet (250 μg OTA/kg of feed) during 4 weeks of fattening. OTA concentrations were quantified using a validated immunoassay method (ELISA) and high-performance liquid chromatography with fluorescence detector (HPLC-FD). The highest mean OTA concentration in pig tissues was determined in kidneys of exposed animals (13.87?±?1.41 μg/kg), followed by lungs (10.47?±?1.97 μg/kg), liver (7.28?±?1.75 μg/kg), spleen (4.81?±?0.99 μg/kg), muscle tissue (4.72?±?0.86 μg/kg), fat tissue (4.11?±?0.88 μg/kg), heart (3.71?±?1.09 μg/kg), and brain (3.01?±?0.25 μg/kg). Furthermore, on the last day of exposure (day 28), significantly higher mean OTA levels were determined in urine (16.06?±?3.09 μg/L) in comparison to serum (4.77?±?1.57 μg/L) showing that OTA urine analysis could be a good marker to identify elevated levels of this contaminant in porcine tissues used for human consumption. This study gave guidelines for the most efficient OTA control in pig-derived biological materials that can be exercised at slaughterhouses.  相似文献   

10.
The occurrence of ochratoxin A, fumonisin B1 and B2 has been investigated in maize samples collected in 1996 (105 samples) and 1997 (104 samples) in 14 counties of Croatia, including Brodsko-Posavska county, the main area of Balkan endemic nephropathy in Croatia. Ochratoxin A and fumonisins co-occurred in 21% of the examined samples. In particular, ochratoxin A (OTA) was found in 10 samples (10%) of the 1996 and 36 samples (35%) of the 1997 crops with mean concentrations of positive samples of 37.9 ng/g and 57.1 ng/g, and highest concentrations at 223.6 ng/g and 613.7 ng/g, respectively. Similar incidence of OTA contamination was observed in 1996 samples from both endemic and non endemic areas of Balkan nephropathy, whereas a significant difference (P<0.01) was found between the two areas in 1997, with 50% and 20% incidence of contamination in the endemic and non endemic area, respectively, and relevant OTA mean concentration of positive samples of 73.4 ng/g and 20.2 ng/g. High incidence of infection byPenicillium spp. (potential OTA producers) was found in all tested samples, with mean values of 88% and 93% in samples of 1996 and 1997, respectively. With respect to fumonisin B1 (FB1) and B2 (FB2) all but one of the 1996 samples were contaminated, with highest and mean concentrations of positive samples (FB1+FB2) at 11661 ng/g and 645 ng/g, respectively. Similar incidence of positive samples (93%), but lower contamination levels (mean 134 ng/g, maximum 2524 ng/g) were found in 1997 samples. The results of fumonisin analysis were in agreement with the mycological analysis showing higher incidence of Fusarium infection in samples of 1996 with respect to those of 1997. These data provide additional information on the occurrence of ochratoxin A in Balkan endemic nephropathy areas and, for the first time, its co-occurrence with other nephrotoxic compounds, such as fumonisins, that may contribute to the disease development. However the finding of these mycotoxins in the non-endemic areas, also at high levels, do not allow to draw a conclusion about their role in the etiology of the disease.  相似文献   

11.
Ochratoxin A (OTA) and citrinin (CIT) are both nephrotoxic and teratogenic in animals, and the occurrence of these mycotoxins in food may cause adverse health effects in humans. Data on the combined exposure to these food contaminants are still scarce, especially in pregnancy. Therefore, a biomonitoring study was conducted to determine the presence of urinary biomarkers of exposure to OTA and CIT in pregnant women in Bangladesh. In total, 54 spot urine samples were collected from residents of a rural and a suburban area of the Savar region in Dhaka district for analysis of OTA and CIT urinary biomarkers by previously validated HPLC-FD and LC-MS/MS methods. Most urines were positive for OTA and CIT biomarkers, with OTA being detected in 93 % (range 0.01–0.84 ng/mL) and CIT biomarkers in 87 % (range 0.02–6.93 ng/mL) of all samples. The mean levels of OTA were different between the rural (0.06?±?0.07 ng/mL) and suburban (0.15?±?0.19 ng/mL) study participants. CIT and its metabolite dihydrocitrinone (HO-CIT) were more than twofold higher in the rural (0.42?±?1.20 and 0.55?±?1.04 ng/mL, respectively) than the suburban (CIT 0.15?±?0.13 ng/mL; HO-CIT 0.23?±?0.18 ng/mL) participants. When a provisional daily intake for CIT was calculated, it exceeded the preliminary tolerable value set by European Food Safety Authority (0.2 μg/kg/day) in 9 % of the rural participants but in none of the urban participants. Urinary biomarker levels for OTA and CIT did not show significant association with intake of certain types of food consumed by the pregnant women, although total CIT biomarker levels were considerably higher among participants who consumed more rice in a day. Overall, this study indicates a frequent co-exposure to OTA and CIT among pregnant women in Bangladesh, at levels similar to those determined recently in the general population of this country.  相似文献   

12.
Results of a 2-year (2009–2010) survey on the occurrence of ochratoxin A (OTA) in swine feed and in feed for laying hens in Portugal are reported. A total of 664 samples (478 swine feed, 186 feed for laying hens) were analyzed by a HPLC method using fluorescence detection with 2 μg kg?1 as detection limit. In swine feed, 31 samples (6.49%) were positive for OTA. In feed for laying hens, 12 samples (6.45%) were OTA-positive. The average levels of contamination were low, with median values of positive samples at 3–4 μg kg?1 in both years and both commodities, although a few samples contained exceptionally high levels (maximum 130 μg kg?1). Only the maximum level sample (swine feed) contained OTA at a concentration exceeding the European Commission guidance value. The remaining OTA concentrations found in feed samples were much lower than the guidance values.  相似文献   

13.
A rapid, simple, and green vortex-assisted emulsification microextraction method based on solidification of floating organic drop was developed for the extraction and determination of ochratoxin A (OTA) with high-performance liquid chromatography. Some factors influencing the extraction efficiency of OTA such as the type and volume of extraction solvent, sample pH, salt concentration, vortex time, and sample volume were optimized. Under optimized conditions, the calibration curve exhibited linearity in the range of 50.0–500 ng L?1 with a coefficient of determination higher than 0.999. The limit of detection was 15.0 ng L?1. The inter- and intra-assays relative standard deviations were in a range of 4.7–8.7%. The accuracy of the developed method was investigated through recovery experiments, and it was successfully used for the quantification of OTA in 40 samples of fruit juice.  相似文献   

14.
The presence of the mycotoxin ochratoxin A (OTA) in cereal grains is due to the growth of toxigenic Penicillium mold on stored crops. Human exposure to OTA is higher in infants, toddlers, and children than in adolescents and adults, based on exposure assessments of ng OTA consumed/kg body weight/day. Ochratoxin A is nephrotoxic and teratogenic in animals, but its effects on juveniles exposed during the reproduction and development period have not been studied. To address this, Fischer rats were exposed to 0, 0.16, 0.4, 1.0, or 2.5 mg OTA/kg diet throughout breeding, gestation, and lactation and its adverse effects were assessed in adult rats and their offspring on postnatal day (PND) 21. There were no effects on implantation but post-implantation fetotoxicity was observed in the 2.5 mg/kg dose group, corresponding to a calculated dose of 167.0 μg/kg bw/day in dams. Adverse effects on body and kidney weights and on clinical parameters indicative of renal toxicity were significant in adult rats exposed to 1.0 mg OTA/kg diet (55.2 and 73.3 μg/kg bw/day in adult males and females, respectively) and in PND21 rats at the 0.4 mg/kg dose (33.9 μg/kg bw/day in dams), suggesting that weanling rats were more sensitive to OTA than adults. Overall, nephrotoxicity was the primary effect of OTA in weanling rats exposed throughout gestation and lactation at sub-fetotoxic concentrations in diet.  相似文献   

15.
《Biomarkers》2013,18(8):673-678
Abstract

The mycotoxin ochratoxin A (OTA) can elicit a wide range of toxic properties including embryotoxicity and teratogenicity. OTA crosses the placenta at early gestation rather than in late gestation, maternal OTA exposure may represent a risk for the developing fetus. The study focuses on the assessment of OTA intake of pregnant women (aged 19–40 years) in the first trimester of pregnancy by means OTA levels in 100 blood serum samples by high-performance liquid chromotography with fluorescence detection (HPLC-FD) method and comparison with dietary OTA exposure in pregnant women. Of all, 96% tested serum samples were positive with values ranging from 0.1 to 0.35?µg/l with a mean value of 0.15?µg/l.  相似文献   

16.
Recently, considerable attention has been paid to the negative effects caused by the presence and constant increase in concentration of heavy metals in the environment, as well as to the determination of their content in human biological samples. In this paper, the concentration of chromium in samples of blood and internal organs collected at autopsy from 21 female and 39 male non-occupationally exposed subjects is presented. Elemental analysis was carried out by an electrothermal atomic absorption spectrometer after microwave-assisted acid digestion. Reference ranges of chromium in the blood, brain, stomach, liver, kidneys, lungs, and heart (wet weight) in the population of Southern Poland were found to be 0.11–16.4 ng/mL, 4.7–136 ng/g, 6.1–76.4 ng/g, 11–506 ng/g, 2.9–298 ng/g, 13–798 ng/g, and 3.6–320 ng/g, respectively.  相似文献   

17.
Citrinin (CIT) and Ochratoxin A (OTA) are nephrotoxic mycotoxins which can co-occur in food commodities, resulting in internal exposure. Studies in many countries reported on the presence of OTA in human blood; however, such biomonitoring data for CIT is still scarce. This study was conducted to characterize both CIT and OTA biomarker levels in plasma of volunteers since food analysis data are insufficient to assess human exposure in Bangladesh. In total 104 blood samples were collected from university students in 2013 (sampling 1: n?=?64, midsummer) and 2014 (sampling 2: n?=?40, end winter) for analysis of CIT and OTA and their metabolites HO-CIT and OTα by LC-MS/MS and HPLC-FD techniques, respectively. CIT and HO-CIT were detected in 90% (max 2.70 ng/mL) and 85% (max 1.44 ng/mL) of all samples. Mean levels in sampling 2 (CIT 0.47 ng/mL; HO-CIT 0.40 ng/mL) were higher than in sampling 1 (0.25 ng/mL; 0.37 ng/mL) indicative of variable CIT exposure. OTA was present in all (max 6.63 ng/mL) and OTα in 98% (max 0.99 ng/mL) of the samples. In sampling 1, mean OTA (0.85 ng/mL) was higher than in sampling 2 (0.51 ng/mL); the reverse situation was found for OTα mean levels. The calculated dietary OTA intake among the students (mean 9.9; max 91.7 ng/kg bw/week) was lower than the tolerable weekly intake for this mycotoxin (120 ng/kg bw/week) set by EFSA. But frequent co-exposure to CIT should be considered, and the results of this study indicate the necessity to identify major sources of CIT and OTA intake in the Bangladeshi population.  相似文献   

18.
The occurrence of toxigenic fungi producing aflatoxins and ochratoxin A in foodstuffs was studied in the Czech Republic. Twenty five commodities were collected at twelve collection places in the Czech Republic (300 food samples). The presence of potentially toxigenicAspergillus flavus was observed in 28% of the sampled foods (black pepper, caraway seeds, fruit tea, black tea, oat flakes, fine flour, rolled oat flakes and semolina) in the year 1999, and in 25% of the sampled foods (black pepper, black tea, fine flour) in the year 2000.A tamarii (aflatoxins producer) was found in 3 black pepper samples (25%) in both years. Aflatoxins were detected in black pepper and caraway seed samples in the year 1999 and in sweet red pepper in the year 2000.A parasiticus andA nomius were not isolated. Aspergillus section Nigri (potential producer of ochratoxin A) was detected in some foodstuffs. Ochratoxin A was detected in raisins.Penicillium verrucosum andA ochraceus were not isolated from foodstuffs.  相似文献   

19.
Brewer’s yeast comprises different strains ofSaccharomyces cerevisiae used for beermaking. It is additionally used as a nutrient supplement to increase the intake of B vitamins and is recommended primarily for children in growth, women during pregnancy and lactation and persons during convalescence. A total of 51 samples of brewer’s yeast from the German market were analysed for the occurrence of ochratoxin A (OTA) by means of immunoaffinity clean up and HPLC with fluorescence detection. Thirty-two samples (63%) were found to be naturally contaminated with OTA in the range from the detection limit (0.03) to 1.53 ng/g. Mean values of the positive samples varied between 0.10 ng/g (powder) and 1.2 ng/g (dragees). In a worst case scenario, the consumption of brewer’s yeast could enhance the calculated daily intake for the German population by 10 to 14 ng OTA/day and person and increase the intake particularly for children from 1.3 up to about 1.9 ng/kg body weight.Thus, the results document that food supplements consisting of natural brewer’s yeast from the brewing process are a yet unknown source for the intake of ochratoxin A and a potential exposure risk. The screening of brewer’s yeast food supplements for OTA is therefore recommended in the context of food safety and quality control.  相似文献   

20.
Forty samples of dried vine fruit (raisin, n?=?22; currant, n?=?18) were collected in 2009?C2011 from the Iranian market. Aflatoxins (AFs) and ochratoxin A (OTA) were determined in these samples after immunoaffinity column clean-up by high performance liquid chromatography (HPLC) with fluorescence detection. The limit of quantification (LOQ) for AFs B1. B2, G1, G2, and OTA were 0.62, 0.50, 0.70, 0.40, and 0.42?ng/g, respectively. AFB1 was found in one sample of raisin (0.64?ng/g) and in two samples of currant (0.20 and 0.63?ng/g). AFB2 (0.33?ng/g) and AFG2 (0.49?ng/g) were found in 2 samples of currant. OTA was detected in 3 of the 22 samples of raisin (mean 2.21?ng/g) and in one sample of currant (2.99?ng/g). The results show that in AFs and OTA levels are well below the regulatory limits both of the European Union and of Iran.  相似文献   

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