河北省玉米贮藏期黄曲霉毒素B1污染调查及安全性评价

为了调查河北省玉米黄曲霉毒素的污染情况,并对玉米的安全性做出初步评价,从河北省不同玉米产地采集贮藏期的玉米样品92个,采用ELISA酶联免疫检测技术对玉米样品进行黄曲霉毒素B_1检测并根据国家标准进行安全性评价。结果显示,黄曲霉毒素B_1检出率为84.8%,根据食品和饲料中黄曲霉毒素B_1的限量标准,符合食用标准的玉米占87.0%,符合饲用标准的占95.7%。冀中南生产区域玉米黄曲霉毒素B_1污染普遍,但整体污染程度较低。对于黄曲霉毒素污染超标玉米,应加强其安全性跟踪监控工作。     

花生油污染黄曲霉毒素的去毒探讨

<正>霉菌繁殖容易引起粮油霉坏变质,玉米、花生极易引起黄曲霉菌污染而产生黄曲霉毒素。研究表明,黄曲霉毒素(Aflato－xin)是一强烈的致癌物质,污染黄曲霉毒素的玉米、花生等食物能诱发实验动物的肝癌。肝癌的高发与食物中黄曲霉毒素污染有密切联系。因此,粮油的防霉去毒     

高效液相色谱法检测玉米制品和坚果制品中的黄曲霉毒素

目的是了解市售玉米制品和坚果制品中的黄曲霉毒素污染状况。方法为结合免疫亲和样品前处理技术,采用高效液相色谱法测定市售玉米制品、坚果制品中的4种黄曲霉毒素。检测了25份市售玉米制品和24份坚果制品,结果显示,其中玉米制品的阳性率为36%,坚果制品中未检出。结论得出,目前市售食品中黄曲霉毒素污染问题主要存在于玉米及其制品中,污染程度虽不高,但由于黄曲霉毒素的强烈致癌作用,还是应该引起重视。     

玉米中黄曲霉毒素的检测与降解

阐述了黄曲霉毒素的性质及黄曲霉毒素在我国玉米中的污染情况.通过对目前玉米中黄曲霉毒素主要检测方法和降解方法的比较、分析,为今后的研究和实际应用提供参考.     

2020年饲料原料霉菌毒素污染状况调查

目的 为更好的指导饲料生产企业对原料质量的把控、采购及配方设计,汇总分析了2020年饲料原料霉菌毒素污染状况。方法 采用胶体金免疫层析法或上转发光免疫分析法（up-conversion immunoassays, UPT）对安佑集团各分子公司在2020年度所收集（含退货）的28519份大宗饲料原料中的呕吐毒素、玉米赤霉烯酮和黄曲霉毒素B1含量进行快速检测。结果 对比安佑集团企业标准,2020年饲料原料霉菌毒素污染总超标率为0.92%,污染整体情况较轻,其中上半年污染较重,主要由玉米副产物和次粉霉菌毒素污染超标所致,下半年霉菌毒素污染程度整体较轻,但第4季度玉米的玉米赤霉烯酮和黄曲霉毒素B1污染情况加重,玉米的霉菌毒素整体达中度污染;从产地来源看,2020年山东、湖北产地的麸皮和次粉呕吐毒素中度污染,四川、陕西产地的次粉重度污染;四川产地的米糠黄曲霉毒素B1达中度污染,山东产地的玉米呕吐毒素和江苏产地的玉米黄曲霉毒素B1达重度污染;且饲料原料中的霉菌毒素并非单一存在,多数情况下是多种毒素共存。结论 与2019年饲料原料霉菌毒素污染调查数据相比,2020年原料的霉菌毒素污染程度较轻。     

RIDA~QUICK Aflatoxin黄曲霉毒素快速检测条:保障粮食收购的安全

黄曲霉毒素是黄曲霉、寄生曲霉等产生的代谢产物,对人、畜肝脏的损害程度为所有生物毒素之首,其中黄曲霉毒素B1的毒性是剧毒化学药品氰化钾的10倍以上,具有很强的致癌性,在1988年被国际癌症研究机构列为I级致癌物。黄曲霉毒素容易污染花生、玉米、大米、小麦、豆类、坚果类、肉类、乳及乳制品,水产品等食品,其中花生和玉米最容易受到污染。     

浅谈生猪黄曲霉毒素中毒

1998年夏秋季节,由于连续降雨,持续时间较长,在高温高湿的气候条件下,致使玉米的霉变严重,大量玉米污染黄曲霉毒素,污染毒素的玉米,由于霉变未达到腐烂的程度,不易察觉,秋收后,很多农民把污染毒素的玉米作饲料饲养生猪,问题才逐渐暴露出来,发生了大面积的生猪发病及不明死亡,病畜注射抗生素等药物也无效果,在检查饲料时,发现玉米饲料在槽中的剩余突出,饲料玉米有苦味.在紫外线照射下一些玉米谷皮及胚部有荧光反应,尤以胚部严重,因而判断系黄曲霉毒素中毒引起的生猪发病及死亡.笔者简要介绍黄曲霉毒素中毒生猪的宰后检验结果,黄曲霉毒素的特性,中毒预防措     

12种植物性饲料原料中霉菌毒素污染状况的调查分析

对采集的12种植物性饲料原料中的59份样品进行玉米赤霉烯酮、黄曲霉毒素B1、B2、G1、G25种霉菌毒素的检测,结果表明,玉米赤霉烯酮共10种原料26份样品有检出;黄曲霉毒素B1共7种原料10份样品有检出;黄曲霉毒素B2共2种原料2份样品有检出;黄曲霉毒素G1、G2未检出。饲料原料受玉米赤霉烯酮、黄曲霉毒素B1污染较多,应加以重视。     

农产品免黄曲霉毒素污染储藏新法

众所周知,食品或饲料如被黄曲霉毒素污染,将对人和家畜健康产生极大危害。此污染源自于黄曲霉与寄生曲霉(它们的代谢产物为黄曲霉毒素)。黄曲霉与寄生曲霉往往作为储藏真菌存在于许多农产品中。一旦条件有利,它们便大量繁殖,与此同时产生黄曲霉毒素造成污染。经研究发现:2-氯乙基磷酸(CEPA,一种能产生乙烯的化合物)能抑制黄曲霉与寄生曲霉菌株生物合成黄曲霉毒素。本研究为检验用CEPA抑制黄曲霉毒素污染花生与玉米的效果。     

RIDA(R) QUICK Aflatoxin黄曲霉毒素快速检测条:保障粮食收购的安全

黄曲霉毒素是黄曲霉、寄生曲霉等产生的代谢产物,对人,畜肝脏的损害程度为所有生物毒素之首,其中黄曲霉毒素B1的毒性是剧毒化学药品氰化钾的10倍以上,具有很强的致癌性,在1988年被国际癌症研究机构列为1级致癌物.黄曲霉毒素容易污染花生、玉米、大米、小麦、豆类、坚果类、肉类,乳及乳制品,水产品等食品,其中花生和玉米最容易受到污染.此外,家庭自制发酵食品也能检出黄曲霉毒素;而高温高湿地区的粮油及粮食制品中黄曲霉毒素含量更高.     

Incidence of mycotoxins in maize grains in Bihar State, India

A regular survey of some maize-growing areas of Bihar state, India, for three consecutive years (September 1984 to September 1986) revealed heavy infestations of mycotoxin-producing fungi with different maize samples. Aflatoxin-producing fungi had the highest frequency of occurrence in all the cases and aflatoxins were the most common mycotoxins elaborated by these fungi. Maize samples of the Kharif crop had a greater incidence of aflatoxins (47%) than the samples of rabi crop (17%). Stored maize grains also had a high incidence of aflatoxins (43%). Most of the contaminated samples contained aflatoxins at levels above 20 micrograms/kg.     

Interference of mycotoxin binders with ELISA,HPLC and LC-MS/MS analysis of aflatoxins in maize and maize gluten

ABSTRACT

The aim of this study was to investigate the impact of mycotoxin binders on the determination of aflatoxins in maize and maize gluten using various analytical methods, including ELISA, HPLC and LC-MS/MS. Three types of commercially available mycotoxin binders, yeast cell wall, mineral, and a mixture of mineral and bacterium, were investigated at inclusion levels of 0.1%, 0.2% and 0.4%. The binders were added to maize and maize gluten contaminated with aflatoxins at concentrations between 6.9 and 26.7 μg kg^?1. The samples were analysed and the values were compared with corresponding controls (samples without binders) using ANOVA. The yeast cell wall binder had no significant effect (p=0.05) on the concentration of aflatoxins measured in either maize or maize gluten at any of the three inclusion levels, regardless of which analytical method was used. The mineral binder and the mixed mineral and bacterium binder had no significant effect (p=0.05) on the measured aflatoxin concentrations in either maize or maize gluten at any of the three inclusion levels when analysis was conducted using LC-MS/MS. Inclusion of these binders resulted in significant lower (p<0.01) detection of aflatoxins in both maize and maize gluten when analysis was conducted using ELISA; the effect was dose-dependent. They also resulted in significant lower detection of aflatoxins in maize extracted by methanol/water (70/30 v/v) (p<0.0001) and in maize gluten extracted by acetonitrile/water (80/20 v/v) (p<0.05) when analysis was conducted using HPLC. However, neither the mineral binder nor the mixed mineral and bacterium binder had significant effects (p=0.05) on aflatoxin concentrations measured in maize using HPLC, when extracted by acetonitrile/water (80/20 v/v). The study demonstrated that mycotoxin binders could result in underestimation of the levels of aflatoxin contamination, depending on the nature of the binder, the extraction solvent used in the analytical method, and the composition of tested sample.     

Fate of aflatoxins and fumonisins during the processing of maize into food products in Benin

The fate of aflatoxins and fumonisins, two mycotoxins that cooccur in maize, was studied through the traditional processing of naturally contaminated maize in mawe, makume, ogi, akassa, and owo, maize-based foods common in Benin, West Africa. Levels of total aflatoxin and fumonisin were measured at the main unit operations of processing, and the unit operations that induce significant reduction of mycotoxin level were identified. Overall reduction of mycotoxin level was more significant during the preparation of makume (93% reduction of aflatoxins, 87% reduction of fumonisins) and akassa (92% reduction of aflatoxins, 50% reduction of fumonisins) than that of owo (40% reduction of aflatoxins, 48% reduction of fumonisins). Sorting, winnowing, washing, crushing combined with dehulling of maize grains were the unit operations that appeared very effective in achieving significant mycotoxin removal. Aflatoxins and fumonisins were significantly recovered in discarded mouldy and damaged grains and in washing water. Fermentation and cooking showed little effect. During the preparation of ogi and akassa, reduction of fumonisin levels measured in food matrix was lower (50%) compared to mawe and makume, probably due to significant fumonisin release in ogi supernatant. Consequently, the use of ogi supernatant for preparing beverages or traditional herbal medicines could be harmful as it is likely to be contaminated with mycotoxin from the raw maize.     

Detection of moulds producing aflatoxins in maize and peanuts by an immunoassay

An enzyme-linked immunosorbent assay (ELISA) was developed to detect moulds producing aflatoxins in maize and peanuts by an antibody produced to extracellular antigen from Aspergillus parasiticus. This antibody recognized species with phenotypic similarities to A. parasiticus, A. flavus and the domesticated species A. sojae and A. oryzae. For maize samples that were naturally contaminated with aflatoxins, low and high levels of aflatoxin corresponded with low and high ELISA readings for mould antigens, respectively. Maize and peanuts inoculated with 10(2) spores ml(-1) of A. parasiticus and incubated at 15 degrees C for 18 days or 21 degrees C for 7 days were analyzed for mould antigens and aflatoxin levels. At 15 degrees C, mould antigens were detected by day 4 in maize when 0.16 ng g(-1) of aflatoxin was detected by ELISA but not by thin layer chromatography (TLC). Antigens were detected in peanuts by day 4 before aflatoxin was found. Likewise, at 21 degrees C, antigens were detected by day 4 in maize when less than 1 ng g(-1) of aflatoxin was detected by ELISA but not by TLC, but by day 2 in peanuts when no aflatoxin was detected. A. parasiticus could be detected before it could produce aflatoxins. Therefore, this ELISA shows potential as an early detection method for moulds that produce aflatoxins.     

Monitoring and identification of aflatoxins in wheat, gram and maize flours in Bihar state (India).

The occurrence of aflatoxins in some common food commodities: wheat, gram and maize flours is reported. Of the total 416 collections during three years (1987-1989) 162 were recorded to be aflatoxin-positive. The incidence of aflatoxins was maximum in the samples of 1987. Most of the contaminated samples contained aflatoxins at levels above 20 micrograms/kg. The environmental conditions and traditional agronomic and storage practices relating to aflatoxin incidence are discussed.     

Aflatoxins in pozol, a nixtamalized, maize-based food

To determine whether pozol, a nixtamalized maize-based food was contaminated with aflatoxins, samples of non-fermented pozol were collected during the period November 2002 to April 2003 from local markets at Comitan in Chiapas, Mexico. The samples were analyzed for the presence of aflatoxins. Nineteen out of one hundred and eleven samples were contaminated with aflatoxin B2 (AFB2) and traces of aflatoxin B1 (AFB1). The percentage of samples contaminated with AFB2 in pozol prepared with white maize was 5.4%. Pozol mixed with toasted cacao paste had a contamination rate of 41.5%. No aflatoxins were detected in pozol prepared with yellow maize. It was found that only 1 of 19 contaminated samples had aflatoxin concentrations above 20 ppb.     

Co-occurrence of fumonisins with aflatoxins in home-stored maize for human consumption in rural villages of Tanzania

This study determined maize-user practices that influence the presence of fumonisin and aflatoxin contamination of maize in food consumed in the rural areas of Tanzania. Samples of the 2005 maize harvest in Tanzania were collected from 120 households and examined for fumonisins and aflatoxins. Information on whether the maize was sorted to remove defective (visibly damaged or mouldy) maize before storage and whether the damaged and mouldy maize or the non-dehulled maize was used as food was also collected. In addition, the percentage of defective kernels in the samples was determined. Ninety per cent of the households sorted out defective maize, 45% consumed the defective maize and 30% consumed non-dehulled maize. In 52% of the samples fumonisins were determined at levels up to 11,048 µg kg^?1 (median = 363 µg kg^?1) and in 15% exceeded 1000 µg kg^?1; the maximum tolerable limit (MTL) for fumonisins in maize for human consumption in other countries. Aflatoxins were detected in 18% of the samples at levels up to 158 µg kg^?1 (median = 24 µg kg^?1). Twelve per cent of the samples exceeded the Tanzanian limit for total aflatoxins (10 µg kg^?1). Aflatoxins co-occurred with fumonisins in 10% of the samples. The percentage defective kernels (mean = 22%) correlated positively (r = 0.39) with the fumonisin levels. Tanzanians are at a risk of exposure to fumonisins and aflatoxins in maize. There is a need for further research on fumonisin and aflatoxin exposure in Tanzania to develop appropriate control strategies.     

Development of a quantitative lateral flow immunoassay for the detection of aflatoxins in maize

An immunoassay-based lateral flow device for the quantitative determination of four major aflatoxins in maize has been developed. The one-step assay has performance comparably with that of other screening methods, as confirmed by the intra- and the inter-day precision of the data (RSD 10-22%), and can be completed in 10 min. Quantification was obtained by acquiring images of the strip and correlating intensities of the coloured lines with analyte concentration by means of a stored calibration curve carried out by diluting aflatoxins in the extract from a blank maize sample. Limit of detection (1 μg kg?1) and dynamic range (2-40 μg kg?1) allows the direct assessment of aflatoxin contamination in maize at all levels of regulatory relevance. All reagents are immobilized on the lateral flow device. In addition, very simple sample preparation, using an aqueous buffered solution, has been demonstrated to allow the quantitative extraction of aflatoxins. Twenty-five maize samples were extracted with the aqueous medium and analyzed by the developed assay. A good correlation was observed (y = 0.97x + 0.07, r2= 0.980) when data was compared with that obtained through an official method. The developed method is reliable, rapid and allows for application outside the laboratory as a point-of-use test for screening purposes.     

Aflatoxin accumulation in whole crop maize silage as a result of aerobic exposure

BACKGROUND: Most of the maize silage stored in horizontal silos is exposed to air and can be spoiled by fungi. Potentially toxigenic fungi have been found in maize silage, and about 300 mycotoxins have been detected. Among these mycotoxins, the most harmful for feed and food safety are aflatoxins. The aim of the study was to set up a specific method to detect aflatoxins in maize silage, and to investigate whether aflatoxin contamination in maize silage depends on the level of field contamination of the crop, and whether the occurrence of aerobic spoilage during ensiling has any effect on the final contamination of the silage. RESULTS: A method for the determination of aflatoxin B₁, B₂, G₁ and G₂ in maize silage using high‐performance liquid chromagraphy with fluorescence detection has been developed and validated. Recoveries of aflatoxin B₁, B₂, G₁, and G₂ spiked over the 0.25 to 5 µg kg^?1 range averaged 74–94%. The results of laboratory scale and farm scale ensiling experiments indicated that aflatoxins could increase when silage is exposed to air during conservation or during the feed‐out phase. CONCLUSIONS: The method here proposed to detect aflatoxins in silages has proved to be sensitive and is able to detect levels of 0.1 and 0.5 ng mL^?1 for AFB₁ and AFG₁, and between 0.025 and 0.125 ng mL^?1 for AFB₂ and AFG₂. This study also provides evidence of aflatoxin accumulation in whole crop maize silage as a result of aerobic exposure. Copyright © 2011 Society of Chemical Industry     

Comparison of major biocontrol strains of non-aflatoxigenic Aspergillus flavus for the reduction of aflatoxins and cyclopiazonic acid in maize

Biological control of toxigenic Aspergillus flavus in maize through competitive displacement by non-aflatoxigenic strains was evaluated in a series of field studies. Four sets of experiments were conducted between 2007 and 2009 to assess the competitiveness of non-aflatoxigenic strains when challenged against toxigenic strains using a pin-bar inoculation technique. In three sets of experiments the non-aflatoxigenic strain K49 effectively displaced toxigenic strains at various concentrations or combinations. The fourth study compared the relative competitiveness of three non-aflatoxigenic strains (K49, NRRL 21882 from Afla-Guard?, and AF36) when challenged on maize against two aflatoxin- and cyclopiazonic acid (CPA)-producing strains (K54 and F3W4). These studies indicate that K49 and NRRL 21882 are superior to AF36 in reducing total aflatoxin contamination. Neither K49 nor NRRL 21882 produce CPA and when challenged with K54 and F3W4, CPA and aflatoxins were reduced by 84-97% and 83-98%, respectively. In contrast, AF36 reduced aflatoxins by 20% with F3W4 and 93% with K54 and showed no reduction in CPA with F3W4 and only a 62% reduction in CPA with K54. Because AF36 produces CPA, high levels of CPA accumulate when maize is inoculated with AF36 alone or in combination with F3W4 or K54. These results indicate that K49 may be equally effective as NRRL 21882 in reducing both aflatoxins and CPA in maize.