淡豆豉炮制过程中黄曲霉毒素含量的动态变化规律分析

目的: 检测淡豆豉炮制过程中不同时间点样本的黄曲霉毒素(AFTs)含量,明确AFTs的动态变化规律及其产生的关键时间点。方法: 按实验室前期已建立的规范炮制工艺制备淡豆豉,获取淡豆豉炮制过程中不同时间点的样本;采用超高效液相色谱-串联质谱法(UPLC-MS/MS)检测各样本中4种AFTs [黄曲霉毒素B₁(AFB₁),AFB₂,AFG₁,AFG₂]含量。结果: 4种黄曲霉毒素在选定的质量浓度范围内与峰面积线性关系良好(R²均大于0.99),重复性相对标准偏差(RSD)0.4%~0.9%,精密度RSD 0.7%~2.6%,稳定性RSD 0.8%~1.74%,加样回收率介于95.09%~107.20%(RSD 3.14%~12.71%);AFB₁含量在淡豆豉整个炮制过程中呈先上升后下降的趋势,在"再闷"第6天时达最高值6.95 μg·kg^-1,再闷第12天后各样本均未检测出AFTs。结论: 本研究建立了简单、快速、灵敏度高且适用于淡豆豉中4种AFTs检测的UPLC-MS/MS法;淡豆豉炮制过程中AFTs含量呈动态变化,表明淡豆豉炮制中生物拮抗作用自然存在,从安全性角度证实淡豆豉炮制中"再闷"环节的重要性和"再闷"时间的合理性。     

2010年某地粮食类食品安全风险监测结果分析

目的了解某地粮食类食品铅、镉、汞和黄曲霉毒素污染状况,为食品安全监管提供依据。方法 2010年对694份粮食类食品标本的铅、镉、汞和黄曲霉毒素污染状况进行监测,并将监测结果与国家相关标准进行对照。结果该地粮食类食品总体合格率为97.41%。大米中铅超标率为9.17%,镉超标率为4.95%,汞超标率为0.92%;镉在大米、小麦粉、玉米面中均被检出,超标率分别为4.95%、4.55%、4.35%;黄曲霉毒素B1检出率为4.17%。不同采集地食品合格率比较,超市高于农贸市场。结论该地粮食类食品污染状况需要引起关注,监管部门今后应加强对各类粮食类食品的监测及安全监管,并科学发布预警信息引导公众正确消费。     

A Three-Year Survey on the Worldwide Occurrence of Mycotoxins in Feedstuffs and Feed

Between January 2009 and December 2011, a total of 7049 corn, soybean/soybean meal, wheat, dried distillers grains with solubles (DDGS) and finished feed samples were analyzed for the occurrence of aflatoxins (Afla), zearalenone (ZEN), deoxynivalenol (DON), fumonisins (FUM) and ochratoxin A (OTA). Samples were sourced in the Americas, Europe and Asia. Afla, ZEN, DON, FUM and OTA were present respectively in 33%, 45%, 59% 64% and 28% of analyzed samples between 2009 and 2011. From the 23,781 mycotoxin analyzes performed, 81% were positive for at least one mycotoxin. Results of this survey are provided by calendar year, in order to potentially show different trends on mycotoxin occurrence in distinct years: by commodity type and within the same commodity, and by region, to potentially reveal differences in mycotoxin contamination in commodities sourced in diverse regions.     

免疫亲和净化-液相色谱-串联质谱测定中成药中14个真菌毒素

目的:建立同时测定中成药中黄曲霉毒素B1、B2、G1、G2,HT-2毒素,T-2毒素,赭曲霉毒素A,伏马毒素B1、B2,玉米赤霉烯酮,α-玉米赤霉烯醇,β-玉米赤霉烯醇,α-玉米赤霉醇以及β-玉米赤霉醇共14个真菌毒素的测定方法。方法:采用PBS溶液和70%甲醇-PBS溶液依次提取样品中真菌毒素,提取液经多功能免疫亲和柱净化,0.1%吐温-PBS溶液和水依次淋洗,甲醇洗脱,氮气流下浓缩定容,测定时采用Waters Xterra C18MS(100 mm×2.1 mm,3.5μm)分析柱,0.3 mL·min-1的流速,梯度洗脱,质谱测定采用多反应监测(MRM)模式。结果:14个真菌毒素的最小检出浓度(LOQ)为1.0～5.0μg·kg-1;4个中成药基质的3个不同水平的添加回收率(n=6)为75.7%～97.9%,RSD为5.3%～13.8%。结论:本方法采用了多功能免疫亲和柱净化,质谱定性定量,加快了检测速度,降低了中成药复杂基体的干扰,方法检测限满足了国内外中成药多个真菌毒素限量控制要求。     

Mycotoxin Co-Occurrence in Milks and Exposure Estimation: A Pilot Study in São Paulo,Brazil

The aim of this study was to conduct a first evaluation on the co-occurrence of aflatoxins (AF) M₁, B₁, B₂, G₁ and G₂; fumonisins (F) B₁ and B₂; deoxynivalenol (DON); de-epoxydeoxinivalenol (DOM-1); ochratoxin A (OTA); zearalenone (ZEN); α-zearalenol (α-ZEL); and β-zearalenol (β-ZEL) in 68 samples of fluid milk consumed in Pirassununga, São Paulo, Brazil. The probable daily intake (PDI) was also calculated for each mycotoxin evaluated. Mycotoxins were determined by liquid chromatography coupled to mass spectrometry. Sixty-two (91.2%) samples contained at least one type of mycotoxin. AFM₁ was found in 6 samples (8.8%), and none of them presented concentrations above the Brazilian maximum permitted level in milk (500 ng/L). Low levels of non-regulated mycotoxins DOM-1, OTA, FB₁, FB₂, α-ZEL and β-ZEL were found in 6 (8.8%), 17 (25%), 10 (14.7%), 3 (4.4%), 39 (57.4%) and 28 (41.2%) samples of milk, respectively. None of the PDIs calculated for the quantified mycotoxins were above recommended values, indicating low exposure through milk consumption in the area studied. However, 21 samples (30.9%) contained 2–4 types of mycotoxins, which warrants concern about the potential adverse effects of mycotoxin mixtures in milks.     

Occurrence of Mycotoxins and Toxigenic Fungi in Cereals and Application of Yeast Volatiles for Their Biological Control

Fungal infections in cereals lead to huge economic losses in the food and agriculture industries. This study was designed to investigate the occurrence of toxigenic fungi and their mycotoxins in marketed cereals and explore the effect of the antagonistic yeast Cyberlindnera jadinii volatiles against key toxigenic fungal strains. Aspergillus spp. were the most frequent contaminating fungi in the cereals, with an isolation frequency (Fr) of 100% in maize, followed by wheat (88.23%), rice (78.57%) and oats (14.28%). Morphological and molecular identification confirmed the presence of key toxigenic fungal strains in cereal samples, including A. carbonarius, A. flavus, A. niger, A. ochraceus and A. parasiticus. Aflatoxins (AFs) were detected in all types of tested cereal samples, with a significantly higher level in maize compared to wheat, rice, oats and breakfast cereals. Ochratoxin A (OTA) was only detected in wheat, rice and maize samples. Levels of mycotoxins in cereals were within EU permissible limits. The volatiles of Cyberlindnera jadinii significantly inhibited the growth of A. parasiticus, A. niger and P. verrucosum. The findings of this study confirm the presence of toxigenic fungi and mycotoxins in cereals within the EU permissible limits and the significant biocontrol ability of Cyberlindnera jadinii against these toxigenic fungi.     

AFB_1所致实验性大鼠急性肝损伤的组织学、组织化学及超微病理学研究

应用组织学、酶组织化学和电镜技术,系统观察了黄曲霉毒素B_1(AFB_1)诱发的大鼠肝损伤。发现以汇管区周围肝细胞变性坏死为主的组织学改变、SDH和ATPase活性明显降低、ACPase活性增高等酶组化反应和肝窦扩张、窦内充填坏死肝细胞碎屑和凋落小体以及肝细胞核仁变性、核仁帽形成、核仁溶解、内浆网扩张、脂肪变性、大量自噬小体出现等超微结构损伤。笔者认为,AFB_1对肝细胞膜以及膜性结构的直接毒性作用是导致肝细胞急性变性坏死的主要因素。     

中药真菌毒素质量控制概况、限量标准制定及有关问题的思考

外源性有害残留物污染引起的中药安全性问题日益受到关注。中药在种植、采集、贮藏、制备、运输过程中可导致真菌毒素污染,给中药带来安全风险。通过对中药中真菌毒素质量控制、限量标准制订情况进行概述,分析梳理中药中真菌毒素质量控制及限量标准的现状,并对存在的问题进行归纳总结,针对中药真菌毒素的监管提出建议,以保证中药质量,促进行业发展。     

Critical Assessment of Mycotoxins in Beverages and Their Control Measures

Mycotoxins are secondary metabolites of filamentous fungi that contaminate food products such as fruits, vegetables, cereals, beverages, and other agricultural commodities. Their occurrence in the food chain, especially in beverages, can pose a serious risk to human health, due to their toxicity, even at low concentrations. Mycotoxins, such as aflatoxins (AFs), ochratoxin A (OTA), patulin (PAT), fumonisins (FBs), trichothecenes (TCs), zearalenone (ZEN), and the alternaria toxins including alternariol, altenuene, and alternariol methyl ether have largely been identified in fruits and their derived products, such as beverages and drinks. The presence of mycotoxins in beverages is of high concern in some cases due to their levels being higher than the limits set by regulations. This review aims to summarize the toxicity of the major mycotoxins that occur in beverages, the methods available for their detection and quantification, and the strategies for their control. In addition, some novel techniques for controlling mycotoxins in the postharvest stage are highlighted.     

免疫亲和柱净化UPLC-MS-MS测定天麻药材中黄曲霉毒素的含量

目的：研究建立了免疫亲和柱净化UPLC-MS-MS测定天麻药材中黄曲霉毒素B₁,B₂,G₁,G₂的含量测定方法。方法：采用甲醇溶液超声提取、玻璃纤维滤纸滤过、黄曲霉毒素亲和免疫柱净化的方法对天麻药材样品进行处理,以超高液相色谱-三重四级杆串联质谱仪（UPLC-MS-MS）对黄曲霉毒素B₁,B₂,G₁,G₂含量进行研究并测定。结果：被测定的4种黄曲霉毒素分别在选定的范围内线性关系良好,精密度、重复性、准确度均良好,利用标准参考物质对本方法的验证结果良好,采用所建立的方法对30批不同产地天麻药材中黄曲霉毒素B₁,B₂,G₁,G₂含量进行了测定,结果均未检出。结论：该方法科学、可行、方便、快速,适用于对天麻药材中黄曲霉毒素B₁,B₂,G₁,G₂进行含量测定。