Survey of Canadian retail coffees for ochratoxin A

One-hundred and one specimens of coffee were gathered from retail outlets across Canada and analysed for ochratoxin A. Seventy-one specimens were roasted beans or roasted ground coffee, and 30 were instant (or 'soluble') coffees. All samples were extracted with methanol-sodium bicarbonate. The extracts were cleaned up either by immunoaffinity column chromatography or by a combination of solid-phase extraction and immunoaffinity column chromatography. Ochratoxin A was quantified by liquid chromatography (LC) with fluorescence detection. The minimum quantifiable level was 0.1 ng g^-1. Ochratoxin A was present, above the minimum quantifiable level, in 42 (59%) of 71 beans and ground coffee and in 20 (67%) of 30 instant coffees. The mean ochratoxin A level in the positive samples of beans and ground coffee was 0.6 ng g^-1, and the mean level in the positive samples of instant coffee was 1.1 ng g^-1.     

Ochratoxin A in cereal-based baby foods: occurrence and safety evaluation

Ochratoxin A is a typical cereal contaminant with strong nephrotoxic activity. To estimate the quantity of ochratoxin A that can be taken in by a child in the weaning period, several samples of cereal-based baby foods were analysed. Although most samples analysed contained ochratoxin A in undetectable amounts or below the Italian legal limit of 0.5 μg kg -1 , some irregular products were found. In particular, the analyses of the 119 batches (338 samples) of baby foods considered indicated that: 20 batches (16.8%) contained detectable quantities of ochratoxin A and four of these (3.4% of the total) contained ochratoxin A above the Italian permitted value. All samples coming from agricultural practices based on integrated pest management contained undetectable amounts of ochratoxin A, while ~5% of batches coming from conventional and organic agricultural practices were above the legal limit. On the basis of the established provisional tolerable weekly intake (PTWI), there is no significant toxicological risk for a child who occasionally consumes a formula with ochratoxin concentration slightly above the permitted level. However, stricter controls have to be applied to reject the batches containing irregular concentrations of ochratoxin A.     

Detection and quantification of Ochratoxin A in milk produced in organic farms

Dairy cows (as all other ruminants) possess physiological systems for mycotoxins’ detoxification. However, in organic farming practices the detoxification could be impaired because of possible higher contamination of feedstuff, changes in rumen pH and other factors. So the organic milk could be at risk in this respect. The results of an investigation on the presence of Ochratoxin A (OTA) in 63 samples of organic and 20 samples of conventional milk are reported in this paper. The quantification was carried out by means of the HPLC method described by Sørensen and Elbœk (2005). The method has been modified in the purification step so as to shorten the time of analysis and lower the cost of the assay.     

Ochratoxin A (OTA) in coffee: nation-wide evaluation of data collected by German Food Control 1995-1999

The evaluation process involved data collected by Official Food Control Laboratories during the period 1995 until 1999. A total of 613 samples analysed for ochratoxin A and complying with a detection limit lower than 0.6 microg/kg were evaluated. With the assistance of statistical process analysis the median concentrations for green coffee (0.4 microg/kg), for roasted coffee (0.6 microg/kg), for decaffeinated roasted coffee along with low-acid decaffeinated roasted coffee (0.4 microg/kg) as well as for soluble coffee (0.7 microg/kg) were determined. The result is a mean daily total intake per consumer of 9 ng OTA.     

Potassium and other mineral contents of green, roasted and instant coffees

This paper describes experimental work that has been carried out to determine the normal ash, sulphated ash and potassium contents of four selected and specified green coffees, together with the relationship between extraction yield and potassium content of prepared instant coffees. In conjunction with previously published data on the mineral contents of coffees, the relationship is shown to be capable of giving only an arbitrary measure of extraction yield, primarily on account of the variability of mineral and potassium content of different green coffees, and to a leaser extent on the variable process conditions that are commercially used in extraction. The reasons for the variability of mineral content, which can be at least ±10% of the average, are discussed.     

浙江省5大类食物中赭曲霉毒素A暴露评估

目的 评价浙江省居民膳食赭曲霉毒素A(OTA)暴露风险。方法 收集2018—2019年浙江省居民消费食物5大类24种共518份,结合浙江省2015—2016年膳食消费量调查数据,对居民OTA膳食暴露进行评估。结果 OTA只在谷物及其制品中检出,而水果、茶叶、膨化食品、婴幼儿谷类辅食中均未检出OTA。燕麦及其制品OTA检出率最高为16.1%(5/31);OTA阳性样本含量范围为0.53～4.00μg/kg,其中燕麦及其制品检出含量最高,为4.00μg/kg;OTA含量均未超过我国限量标准（5μg/kg）。暴露评估显示,浙江省全人群中绝大多数消费情景下谷物及其制品膳食OTA暴露量为0.004～7.360 ng/kg BW,在OTA的安全摄入范围内（14 ng/kg BW）;少数高污染高消费情景下,稻谷OTA摄入量为19.627 ng/kg BW,是安全摄入量的140.19%。不同年龄组人群以1～6岁组每日摄入量最高,为0.014～34.644 ng/kg BW,是安全摄入量的0.10%～247.46%。本研究中稻谷是浙江省居民膳食OTA的主要贡献食物,不同消费人群贡献率达到87.22%～9...     

赭曲霉毒素A快速检测技术研究进展

赭曲霉毒素A危害大且污染范围广,快速、灵敏的赭曲霉毒素A的检测方法可以有效监控其污染。本文综述了赭曲霉毒素A的快速检测技术研究进展,集中在酶联免疫技术、胶体金免疫层析技术、免疫亲和柱层析净化-荧光光度法联用技术以及其较新的非免疫技术等,并对其中存在的问题和发展方向进行了讨论与展望。     

Ochratoxin A in grape pekmez (grape molasses) consumed in Turkey

In this study, ochratoxin A (OTA) in 55 home-made, 20 commercial and 7 organic grape pekmez (grape molasses) produced in Turkey was investigated. OTA was detected in 73% of home-made pekmez samples, in 35% of commercial pekmez samples and in 71% of organic pekmez samples. Eleven per cent of the samples had OTA levels higher than 10 µg/l. The highest OTA level (31 µg/l) was detected in organic pekmez. The maximum OTA levels were 15 µg/l and 12 µg/l in home-made and commercial pekmez samples, respectively. Mean OTA levels were 3.5 µg/l, 1.4 µg/l and 9.2 µg/l in home-made, commercial and organic pekmez samples, respectively. Organic pekmez samples and home-made pekmez samples had higher OTA contamination than commercial pekmez samples. Results confirm OTA contamination in grape pekmez samples, indicating that the OTA level in grape pekmez could be a potential risk for consumers.     

葡萄酒中赭曲霉素A的研究进展

赭曲霉素A（OTA）是一种真菌毒素,常见于谷物、谷物产品、水果、咖啡、葡萄干、葡萄酒和啤酒中。由于OTA在食物中稳定且不易分解,对人体构成了一种潜在的危害,国际癌症研究机构（IARC）已将其定义为group2B类致癌物。欧洲各国已经对赭曲霉素A进行限量,也制定了相应的官方检测方法。对葡萄酒中赭曲霉素A的性质、毒性、污染现状、产生菌、影响因素和测定方法进行了综述。     

进口葡萄酒中赭曲霉毒素A的含量分析

为了解进口葡萄酒中赭曲霉毒素A的含量和污染状况,本研究建立了无需净化、浓缩,直接进样,采用液相色谱-串联质谱联用法(LC-MS/MS)测定葡萄酒中赭曲霉毒素A的方法。赭曲霉毒素A空白基质标准溶液在1.0～20.0 ng/mL浓度范围内线性良好,方法检测限达到0.05 ng/mL,添加浓度为2.0 ng/mL质控样品的回收率为98.7%～113.2%,精密度<5.7%。应用该方法测定了84个进口葡萄酒样品中赭曲霉毒素A的含量,结果表明,赭曲霉毒素的检出率为100%,含量为0.14～1.10 ng/mL,平均含量为0.32 ng/mL。     

Survey: Ochratoxin A in European special wines

The occurrence of Ochratoxin A (OTA) was examined in 121 special wines made using different winemaking techniques and from many European origins. The wine groups with the highest OTA content and occurrence, above 90%, were those were the must was fortified before fermentation (mean: 4.48 μg/l) and those made from grapes dried by means of sun exposure (mean: 2.77 μg/l). Fortified wines with long aging in wooden casks were about 50% contaminated, with OTA levels below 1.00 μg/l. Wines affected by noble rot, late harvest wines and ice wines did not contain OTA. Overall, 19.8% of the wines studied contained OTA levels above the maximum permissible limit for the European Union (2 μg/kg) in wine (excluding liqueur wines).     

谷物中赭曲霉毒素A化学发光酶免疫分析法的建立

建立了间接竞争化学发光酶免疫法检测赭曲霉毒素A(ochratoxin A,OTA),该方法IC50为112 pg/mL,检出限是2.47 pg/mL,平均批内和批间变异系数分别为7.03%和14.7%。在大米和小麦样本中添加浓度1.5～6μg/kg的OTA标品,平均回收率在66.97%～97.96%之间,与其他常见真菌毒素未见交叉反应。将该方法应用于30份谷物样本(包括20份大米样本和10份小麦样本)中OTA的检测,检测结果与商品化ELISA试剂盒的相关系数R2=0.942 4。该方法简单、灵敏、快速、准确适用于谷物中OTA的检测。     

Ochratoxin A in beverages from Morocco: a preliminary survey

In a preliminary study, samples of Moroccan wines (n = 30), beers (n = 5) and fruit juices (n = 14) were assayed for ochratoxin A (OTA) by HPLC with fluorimetric detection, followed by confirmation by cleavage of the OTA molecule using carboxypeptidase with HPLC-fluorimetric determination of ochratoxin alpha (OT alpha). All the wine samples were contaminated, and the overall median OTA concentration was 0.65 microg/l (range 0.028-3.24 microg/l). One of the 14 samples of fruit juices was contaminated with a concentration of 1.16 microg/l, whereas none of the five beer samples was contaminated. This is the first report on the occurrence of OTA in various beverages from Morocco.     

Ochratoxin A in red pepper flakes commercialised in Turkey

The aim of this study was to investigate the presence of Ochratoxin A (OTA) in red pepper flakes commercialised in Turkey. A total of 75 samples were collected from different supermarkets and traditional bazaars in Istanbul during 2012–2013. OTA analysis was performed by high-performance liquid chromatography equipped with fluorescence detection after immunoaffinity column clean-up. The method was linear in the range 0.05–40 μg kg^?1 (r² = 0.9997). Twenty-seven out of 31 (87.1%) packed red pepper flake samples contained OTA at concentrations ranging from 0.6 to 1.0 μg kg^?1, whereas 100% of the unpacked red pepper flake samples contained OTA, in the range 1.1–31.7 μg kg^?1. Overall, only 4 unpacked samples (5.3%) contained OTA, with a mean value of 23.4 μg kg^?1, which is higher than the European Union limit. It is suggested that OTA content should be carefully considered in red pepper flake samples especially marketed in unpacked form.     

应用胶体金试纸条快速检测赭曲霉毒素A的研究

本文介绍了一种快速检测赭曲霉毒素A的胶体金试纸条的研制方法，其中包括胶体金的生产、金标抗体的制备、试纸条的组装和测试等步骤。测试结果表明赭曲霉毒素A快速检测试纸条的检测限为10ng／ml，检测时间为10min，加上使用方便，经济适用，使之适合于赭曲霉毒素A现场快速检测之用。     

粮食中赭曲霉毒素A的快速定量检测-超高效 液相色谱法

建立了免疫亲和柱净化-超高效液相色谱法快速定量测定粮食中赭曲霉毒素A(Ochratoxin A, OTA)的检测方法。样品经提取后,用免疫亲和柱净化、浓缩, Waters Acquity UPLC BEH C₁₈(50 mm?2.1 mm, 1.7 μm)色谱柱分离,以乙腈∶水∶冰醋酸(体积比 100∶98∶2)为流动相,流速为0.2 mL/min,进样量为1μL,用Acquity荧光检测器激发波长为310nm,发射波长为465 nm处进行检测,赭曲霉毒素A的保留体积小于1.15mL,从样品前处理到分析整个过程小于45 min。根据3倍信噪比的峰响应值,确定赭曲霉毒素A的检出限为0.25pg,在1～50.0 pg范围内呈线性相关,相关系数R₂值为0.998;在小麦、玉米、稻谷样品中加标回收率分别为81.5%～101.2%,81.3%～85.5%,87.8%～97.5%,精密度为3.3%～6.4%。本方法简便快速、灵敏度高、重现性好、溶剂用量少,适用于粮食中赭曲霉毒素A的快速测定。     

检测赭曲霉毒素A(OTA)的酶联免疫吸附法(ELISA)体系的建立

本文分别以自制抗-OTA兔血清抗体(IgG)及鸡卵黄抗体(IgY)就影响检测OTA的ELISA(酶联免疫吸附法)体系因素进行了探讨,建立了检测OTA的ELISA方法。鸡卵黄抗体的最佳ELISA操作参数为:包被抗原浓度为7.5μg/ml,封阻剂浓度为2.5%,抗体稀释倍数为1000,酶标二抗稀释倍数为14000;兔血清抗体的最佳ELISA操作参数为:包被抗原浓度为2.5μg/ml,封阻剂浓度为2.5%,抗体稀释倍数为8000,酶标二抗稀释倍数为10000。IgG和IgY的检测灵敏度分别为10ng/ml和1ng/ml。     

Comparison between capillary electrophoresis and HPLC-FL for ochratoxin A quantification in wine

A capillary electrophoresis method with DAD detection has been developed and validated for ochratoxin A (OTA) determination in wine and compared with a previously validated HPLC-FL method. Although the use of UV detection has originated a high value for the quantification limit and, therefore, this method can not be used yet in the determination of OTA in wine in real samples, the analytical performance of the CE-DAD method is fully satisfactory. The more important advantage of CE is the use of the economical and ecological aqueous borate buffer in the separation process. A good correlation of the results has been obtained when 27 fortified wine samples were analyzed by CE-DAD and HPLC-FL. This work demonstrates that the CE technique is a valuable alternative to HPLC-FL analysis of OTA in wine if fluorescence detection is available.     

Ochratoxin A production by Aspergillus carbonarius on some grape varieties grown in Italy

Fungi responsible for the presence of Ochratoxin A (OTA) in grapes have been identified as belonging to the black aspergilli, Aspergillus section Nigri, among which Aspergillus carbonarius is the main producer. Despite the widespread occurrence of OTA in various types of wine, there is no specific information on the ability of black aspergilli to infect berries and to produce OTA in different grape varieties. The aim of this study was to investigate the susceptibility to A carbonarius of twelve grape varieties representative of a wide range of characteristics, including geographical distribution. In all the conditions of berry status (intact and damaged) and temperature (20 and 25 °C) tested, the incidence of colonised berries and their OTA contents were always low in ‘Bianco d'Alessano’, ‘Pampanuto’ and ‘Uva di Troia’. In contrast, ‘Cabernet Sauvignon’, ‘Trebbiano’ and ‘Verdeca’ showed high fungal incidence and OTA content. The information gathered is relevant for defining risk factors for OTA presence in grapes, even if these data need to be confirmed by observations in vineyards. Copyright © 2004 Society of Chemical Industry     

免疫亲合柱净化高效液相色谱检测啤酒中赭曲霉毒素A

建立了检测啤酒中赭曲霉毒素A(OTA)免疫亲合柱净化高效液相色谱法。该方法为将脱气后的啤酒样品用15%NaCl和2%NaHCO_3的水溶液稀释,然后通过Ochra Test免疫亲和柱净化,采用C18(5μm,250×4.60 mm)色谱柱,流动相为乙腈-水-乙酸(体积比为99:99:2),流速0.900 mL/min;激发波长333 nm;发射波长477 nm;柱温35℃;进样量100μL;外标法定量。方法所采用的标准曲线有良好的线性关系,检出限为0.1 ng/mL,加标回收率为95%～106%,对不同浓度的样品相对标准偏差RSD为2.43%～8.32%。该方法操作简便、准确,回收率高,精密度良好,重现性好,可用于啤酒中赭曲霉毒素A的测定,具有实际应用价值。