Ochratoxin A in plasma of Norwegian swine determined by an HPLC column-switching method

Investigation of ochratoxin a in blood sausages in the Czech Republic: Comparison with data over Europe

Blood sausages consisting of groats, pork, porcine offal, fat, blood, and spices are very popular in the Czech Republic. All these ingredients are potential sources of dietary exposure to ochratoxin A (OTA). OTA has a strong affinity to serum proteins in porcine blood. Thus, the contamination of blood sausages with OTA can be expected. This study aims to evaluate OTA in 200 samples of porcine blood sausages purchased at the Czech market during 2020-2021. The analytical method high-performance liquid chromatography coupled with fluorescence detection with pre-treatment using immunoaffinity columns was employed to determine OTA. The limit of detection was 0.03 ng/g and the limit of quantification 0.10 ng/g. Recovery was 71.6 %. All samples were positive at contents ranging from 0.15 to 5.68 ng/g with a mean of 1.47 ng/g, and a median of 1.26 ng/g. A total of 66% of these samples contained OTA content exceeding the maximum limit of 1 ng/g set in Italy. This study demonstrates that the Czech population is exposed to OTA from blood sausages. The proposed preliminary action limit for OTA in blood sausages should be set at 1 ng/g. No regulatory limits for OTA in blood sausages have been established yet in the European Union legislation. To protect human health, further monitoring of OTA in these products is necessary.

Effects of mycotoxin-contaminated feed on farm animals

Mycotoxins are secondary products produced by fungi in cereals and are frequently found in the livestock industry as contaminants of farm animal feed. Studies analyzing feed mycotoxins have been conducted worldwide and have confirmed the presence of mycotoxins with biological activity, including aflatoxin, ochratoxin A, fumonisin, zearalenone, and deoxynivalenol, in a large proportion of feed samples. Exposure to mycotoxins can cause immunotoxicity and impair reproductive function in farm animals. In addition, exposure of tissues, such as the kidneys, liver, and intestines, to mycotoxins can exert histopathological changes that can interfere with animal growth and survival. This review describes previous studies regarding the presence of major mycotoxins in the feed of farm animals, especially pigs and poultry. Moreover, it describes the adverse effects of mycotoxins in farm animals following exposure, as well as the biological activity of mycotoxins in animal-derived cells. Mycotoxins have been shown to regulate signaling pathways, oxidative stress, endoplasmic reticulum stress, apoptosis, and proliferation in porcine and bovine cells. A clear understanding of the effects of mycotoxins on farm animals will help reduce farm household economic loss and address the health concerns of people who consume these meat and dairy products.

Ochratoxin A in serum of swine from different Brazilian states

The aims of the current study were to monitor the presence of ochratoxin A (OTA) in the serum of slaughtered swine and to investigate its distribution in 4 major geographical regions of Brazil. A total of 400 samples of serum were collected from 4 major states of Brazil (100 samples each). Ochratoxin A concentrations were determined by high-performance liquid chromatography. In Santa Catarina State, 60% of the samples had OTA concentrations ranging from 4.01 to 75.4 mg/l. In Mato Grosso State, 75% of the samples had OTA concentrations ranging from 0.17 to 46.79 mg/l. Bahia State samples had OTA concentrations ranging from 2.72 to 4.13 mg/l in 36% of the samples, whereas 68% of the samples from Rio de Janeiro State had OTA concentrations ranging from 0.16 to 115 mg/l. Only Santa Catarina State and Rio de Janeiro State had serum samples that exceeded 75 mg/l OTA in 20% and 2% of the samples, respectively. A direct relationship between the higher concentrations of OTA in serum from the States of Santa Catarina and Rio de Janeiro and the highest concentrations of OTA in food intended for animal consumption in the same 2 Brazilian states was found in the present study. Ochratoxin A distribution in foodstuffs is very heterogeneous, and an alternative method by which to monitor the presence of OTA in feed includes analyzing swine serum samples, which reflect the toxin content of the ingested feed. This strategy could prevent the occurrence of ochratoxicosis in animal production, reduce economic losses, and minimize hazards to human health.

A survey of ochratoxin A contamination in feeds and sera from organic and standard swine farms in northwest Italy

BACKGROUND

A survey was carried out on conventional (n = 11) and organic (n = 4) swine farms in northwest Italy in order to investigate the occurrence of ochratoxin A (OTA) in feed and serum samples collected from September 2006 to March 2009. Each farm was sampled twice and a total of 30 feed samples and 285 serum samples were collected. OTA levels were determined through extraction, immunoaffinity column purification and high-performance liquid chromatography analysis coupled with fluorimetric detection.

RESULTS

All feed samples resulted to be contaminated with OTA at levels ranging from 0.22 to 38.4 microg kg(-1). The OTA concentrations found in organic feed samples were significantly higher (P < 0.05) than those found in conventional feed samples. All serum samples resulted to be contaminated with OTA at levels ranging from 0.03 to 6.24 ng mL(-1). The OTA concentrations found in organic serum samples were significantly higher (P < 0.001) than those found in conventional serum samples.

CONCLUSION

None of the feed samples contained more than the maximum level (50 microg OTA kg(-1), considering a feed moisture content of 120 g kg(-1)) recommended by the European Commission for OTA in complementary and complete swine feedstuffs. The OTA contamination of organic feed and serum samples was found to be significantly higher than that of conventional feed and serum samples.

Residue of ochratoxin A in swine tissues: Risk assessment

Background: Samples of blood, kidney, and liver per animal were randomly selected from slaughtered pigs (n=60) and analyzed for ochratoxin A. Methods: Determination of ochratoxin A concentration in samples of kidney and liver was performed by high-performance thinlayer chromatography after immunoaffnity column clean up, while for plasma samples, a spectrofluorometric procedure was used. Results: Of the 60 plasma samples, 60% contained ochratoxin A in the range of 2.5-33.3 ng/mL (mean 3.05?5.0 ng/mL), while the incidence of ochratoxin A in kidneys and liver were very similar (70% and 65%). The average ochratoxin A concentration in liver was 3.2?4.35 ng/g (1.2-19.5 ng/g) and in kidneys was 3.97?4.47 ng/g (1.3-22.0 ng/g). A statistically significant difference (p<0.01) was found between region Backa Topola and Kovilj for both liver and kidney samples. In kidney samples originating from region Kovilj and Senta, a statistically significant difference (p<0.01) was found. Mean distribution followed the pattern: kidney>liver>serum (100>80.8>77%). The results from this survey indicated that there was a strong correlation between the ochratoxin A level in serum and liver as well as in the ochratoxin A serum in kidney (r=0.884 and r=0.896, respectively) while the strongest correlation was found between the ochratoxin A level in liver and in kidney (r=0.970). Conclusion: The results of present study show that pork tissues as well as pork products are considered an important source of ochratoxin A in humans.

Survey of slaughtered pigs for occurrence of ochratoxin A and porcine nephropathy in Serbia

Samples of blood, kidney and liver were randomly selected from slaughtered pigs (n=90) and analyzed for ochratoxin A by HPLC. In addition, in order to obtain information on the occurrence of nephropathy, histological examinations were carried out. Of the 90 liver samples, 26.6% contained OTA in the range of 0.22-14.5 ng/g. The incidence of OTA in serum and kidney were very similar (31%, 33.3%), with a maximum concentration of 220.8 ng/mL, and 52.5 ng/g, respectively. Histopathological examination of kidneys confirmed tubulopathies with edema and cell vacuolization. In addition, hemorrhages and necrosis of proximal kidney tubules' cells were found.

The presence of ochratoxin A residue in blood plasma of slaughtered swine

The aim and task of this study was to determine the presence of ochratoxin A (OTA) residue in blood of swine, slaughtered regularly. The fact that ochratoxin A is heterogeneously distributed in a contaminated lot of feed material, makes the sampling problematic. It has been shown that an alternative method to monitor the presence of ochratoxin A in the feed is to analyze blood samples from swine, which reflect the toxin content of the ingested feed. With the aim of determining the presence of ochratoxin A residue in blood of swine slaughtered regularly, and originating from different areas of Vojvodina and Serbia, the samples were collected from the corresponding slaughter. During a three month investigation period, a total of 60 blood samples were analyzed. Spectrofluorimetric method was applied for sample analysis. The presence of the OTA residue was found in 56,6% of the examined plasma samples. The average OTA concentration in plasma was 2.91 ? 4.91 ng/mL (0,0-33,3 ng/mL). The experiment showed that the average OTA concentration in plasma samples originating from different areas of Vojvodina and Serbia, was not significantly low (p > 0,05).

Performance of new clean-up column for the determination of ochratoxin A in cereals and foodstuffs by HPLC-FLD

The performance of the newly developed Mycosep 229 Ochra and Multisep 229 Ochra clean-up columns for ochratoxin A (OTA) determination was evaluated. OTA was subsequently analysed using RP-HPLC with fluorescence detection. Recoveries for frequently contaminated commodities, like cereals, red wine, raisins and green coffee, were estimated. The recoveries obtained for the Mycosep 229 Ochra column were in the range from 87.9 +/- 12.5% (n = 6) for wheat to 99.4 +/- 2.7% (n = 24) for raisins. For Multisep 229 Ochra, recoveries from 76.5 +/- 8.0% (n = 6) for barley to 86.4 +/- 1.4% (n = 24) for raisins were achieved. Limits of detection for all matrices investigated (maize, wheat, rice, barley, raisins, green coffee beans, red wine) were in the range 0.4-2.4 microg kg(-1). The trueness of the method was tested using a certified reference material.

The effects of the Penicillium mycotoxins citrinin, cyclopiazonic acid, ochratoxin A, patulin, penicillic acid, and roquefortine C on in vitro proliferation of porcine lymphocytes

The in vitro effect of each of the Penicillium mycotoxins citrinin (CIT), cyclopiazonic acid (CPA), ochratoxin A (OTA), patulin (PAT), penicillic acid (PIA) and roquefortine C (RQC) on mitogen induced lymphocyte proliferation was determined using purified lymphocytes from 6 piglets. Dose response curves for each mycotoxin were generated and the concentrations producing 50% inhibition of cell proliferation (IC(50)) were estimated. OTA and PAT were the most potent toxins with IC(50) of 1.3 and 1.2 micromol/l, respectively (0.52 and 0.18 mg/l, respectively). Based on molar concentrations, OTA was 15, 30, 40, and 65 times more potent as an inhibitor than PIA, CIT, CPA and RQC, respectively.

The presence of Penicillium and Penicillium mycotoxins in food wastes

A total of 97 samples (48 summer and 49 winter) of food waste from private households were investigated for Penicillium and for mycotoxins. Twenty-five Penicillium species were isolated and Penicillium crustosum, Penicillium brevicompactum, Penicillium chrysogenum, Penicillium expansum, Penicillium roqueforti, Penicillium spinulosum, Penicillium viridicatum, Penicillium commune, Penicillium citrinum and Penicillium solitum were, in decreasing order, the most frequently identified species. Mycotoxins produced by several of these species, including mycophenolic acid, roquefortine C, penitrems A-F and thomitrems A and E, were detected. Of the 48 summer samples, 36 were severely infected and contained more than 10(5) colony forming units (CFU) Penicillium/g sample. The levels of mycotoxins in these samples were in the range 75-19000 microg/kg mycophenolic acid, 40-920 microg/kg roquefortine C, 35-7500 microg/kg penitrem A, 20-2100 microg/kg thomitrem A and 20-3300 microg/kg thomitrem E. Of the 49 winter samples, only one was found to contain mycophenolic acid (4800 microg/kg) and roquefortine C (190 microg/kg), and this sample was severely infected with P. roqueforti. Thirty samples of food waste collected from the food manufacturing industry were also investigated. The number of Penicillium in these samples was between 10(5) and 10(6) colony forming units (CFU)/g sample. Seven of these samples contained mycophenolic acid ranging from 50 to 600 microg/kg and three of these samples also contained roquefortine C in the range 100-250 microg/kg.

Methods of analysis for ochratoxin A

The mycotoxin ochratoxin A (OTA) is produced by the fungi Aspergillus alutaceus and Penicillium verrucosum and has carcinogenic, nephrotoxic, teratogenic and immunosuppressive properties. The levels of OTA in foodstuffs are regulated in several countries, so reliable and sensitive methods are necessary for its determination. Procedures for extraction of OTA from ground foods generally use an organic solvent in the presence of acid or an extraction solvent containing aqueous sodium bicarbonate. Cleanup procedures include partition into aqueous sodium bicarbonate, solid phase extraction (SPE) columns and immunoaffinity chromatography. The latter technique allows detection of sub-ppb levels of OTA in a wide variety of foods and in plasma. The most widely used determinative procedure is reversed phase liquid chromatography (LC) with detection by fluorescence (excitation 330-340 nm, emission 460-470 nm) or, more recently, by tandem mass spectrometry. ELISA methods are also available. Certified reference materials containing OTA have been prepared.

Application of manual and automated systems for purification of ochratoxin a and zearalenone in cereals with immunoaffinity columns

A manual vacuum manifold and an automated solid phase extraction (ASPEC) system were applied for purification of ochratoxin A and zearalenone in wheat, rye, barley, and oat samples with immunoaffinity columns followed by separation with a high-performance liquid chromatograph and fluorescence detection. The immunoaffinity columns for manual sample purification were purchased from a different manufacturer than were those for the automated system. The limit of detection (LOD) for the method for ochratoxin A with a vacuum manifold and ASPEC was 0.1 microg/kg. For the method for zearalenone, the LODs were 1.5 microg/kg with a vacuum manifold and 3 microg/kg with ASPEC. For the methods for ochratoxin A at spiking levels of 0.6 and 2.5 microg/kg, mean recoveries for different cereals varied from 68 to 106%. For the methods for zearalenone, mean recoveries varied from 78 to 117% at spiking levels of 9 and 25 microg/kg. The relative standard deviations of repeatability with various cereals employing both methods were 2-15 and 2-19% for ochratoxin A and zearalenone, respectively.

Survey of Romanian slaughtered pigs for the occurrence of mycotoxins ochratoxins A and B, and zearalenone

Blood serum, kidney, liver and muscle sample per animal were collected from slaughtered pigs (n = 52). The samples were analysed for ochratoxin A (OTA) and B (OTB) by HPLC methods. Zearalenone (ZEA) in serum was analysed by enzyme immunoassay. A total of 98% serum samples were OTA positive in the range of 0.05-13.4 ng/ml and 85% contained under 5 ng OTA/ml. The incidences of OTA in kidney and liver were very similar (79%, 75%) with mean levels of 0.54 ng/g and 0.16 ng/g, respectively. The lowest incidence (17%) and the lowest mean level contamination (0.15 ng/g) were in muscle samples. The mean distribution in tissues followed the pattern serum > kidney > liver > muscle (100%; 0.26%; 8.5%; 2.57%). No kidney, liver or muscle sample was found OTA positive above the maximum admitted limit in Romania (5 ng/g). No sample was found to be positive for OTB. A very similar OTA contamination (mean = 4.19 ng/ml, coefficient of variation = 34.4%) was observed in the serum samples (n = 10) collected from the same farm. A possible difference in regional distribution of OTA in Romania is suggested. Zearalenone was detected only in 17.3% of the serum samples with a maximum concentration of 0.96 ng/ml. This study shows the presence of OTA and ZEA in Romanian slaughtered pigs at levels comparable to those reported in other countries.

A simple HPLC method for the determination of the mycotoxins ochratoxin A and B in blood serum of swine

This paper presents a simple method for the determination of ochratoxins A (OTA) and B (OTB) in pig blood serum. The method includes serum acidification (pH < 1.6) and precipitation of protein with 15% trichloroacetic acid, liquid partitioning with dichloromethane and fluorescence detection. The estimated detection limits were 0.1 ng OTA/ml and 0.2 ng OTB/ml. The mean recoveries from artificially contaminated samples (n = 6 replicates/mycotoxin) spiked at 0.3, 1 and 3ng OTA and OTB/ml, respectively, were 86.8% (s.d. = 8.4) for OTA and 90.0% (s.d. = 9.8) for OTB. Forty-nine Romanian pig blood serum samples (94% of 52 analysed) were found to be naturally contaminated with OTA in the range 0.1-13.4 ng/ml. No sample was found positive for OTB. The method is technically simple, specific, cost effective, suitable for large sample throughput and requires small amount of sample and reagents. It fulfils the criteria for a routine method and could be a suitable toolfor surveying OTA in pig herds and in slaughtered pigs.

Chromatographic methods for the determination of ochratoxin A in animal and human tissues and fluids

This paper gives a review of chromatographic methods used for the determination of ochratoxin A (OA) in animal and human tissues and fluids. These methods are needed for example for monitoring studies of OA occurrence in the food chain and for studies dealing with the OA carry-over. In this survey, emphasis was given to HPLC methods. The review includes sampling, sample storage, extraction, spiking procedures, clean-up, detection and determination, and confirmation procedures. Emphasis is laid on special problems associated with the analysis of animal tissues and fluids.

Determination of ochratoxin A at the ppt level in human blood, serum, milk and some foodstuffs by high-performance liquid chromatography with enhanced fluorescence detection and immunoaffinity column cleanup: methodology and Swiss data

An improved specific analytical method for ochratoxin A (OA) is presented, combining HPLC separation with enhanced fluorescence detection by post-column addition of ammonia. Commercial immunoaffinity columns (Biocode) were for the first time applied to the cleanup of extracts of body fluids; they could be used up to 20 times for blood serum. The extraction efficiency of OA from human serum and milk as well as its derivatization to esters were studied and improved. The quantitation limit for OA was improved and estimated at 5-10 pg/g for human milk and serum. The mean recovery of OA from serum and milk was estimated at 85%. The overall coefficient of variation for OA determinations in serum, milk and selected foodstuffs was estimated at 10% (concentration range 0.01-5 ng/g). The method was applied to sera of 368 blood donors, 10 pairs of maternal and fetal sera, as well as to 40 human milk samples and selected foodstuffs; the results are discussed.