食品中白僵菌素和恩镰孢菌素的污染情况及分析方法研究进展

介绍了食品中白僵菌素(beauvericin,BEA)和包括恩镰孢菌素A(enniatin A,ENA)、恩镰孢菌素A_1(enniatin A_1,ENA_1)、恩镰孢菌素B(enniatin B,ENB)、恩镰孢菌素B_1(enniatin B_1,ENB_1)在内的4种主要的恩镰孢菌素(enniatins,ENNs)的分类、毒性和分析方法,尤其是前处理方式和各方法定量限的研究进展。综述了西班牙、摩洛哥、意大利、日本等部分国家食品中BEA和4种ENNs的污染状况以及这5种毒素与其他主要真菌毒素的协同污染情况。提出了建立针对复杂食品基质中BEA和ENNs测定的高效液相色谱-串联质谱法。     

重要产毒镰刀菌合成白僵菌素和恩镰孢菌素研究进展

白僵菌素(beauvericin,BEA)和恩镰孢菌素(enniatins,ENNs)是由镰刀菌属的多种真菌产生的六酯肽类真菌毒素,该类毒素对上皮细胞、免疫细胞、卵巢细胞等具有很强的毒性作用。本文主要针对能产生BEA和ENNs的重要产毒镰刀菌的形态学特征、分子遗传学特征以及影响BEA和ENNs产生的环境条件如温度、底物等因素进行概述。重点阐述了产毒镰刀菌在两类毒素合成酶的基因水平和氨基酸水平的差异及影响产毒等主要因素,为BEA和ENNs及其产毒镰刀菌的预防和控制提供理论依据。     

2017年山东省部分地区玉米及其制品中白僵菌素和恩镰孢菌素污染调查

目的 调查山东省部分地区2017年产玉米及其制品中六酯肽类真菌毒素,包括白僵菌素(BEA)和恩镰孢菌素(ENNs)中恩镰孢菌素A(ENA)、恩镰孢菌素A₁(ENA₁)、恩镰孢菌素B(ENB)和恩镰孢菌素B₁(ENB₁)的污染情况。方法 从山东省东部、西部、南部和中部四个地区采集2017年产玉米及其制品158份,样品经乙腈-水(85∶15,V/V)提取、固相萃取柱净化后高效液相色谱-串联质谱测定5种毒素的含量。结果 BEA是158份样品中的主要污染毒素,其阳性率和平均值分别为82.3%(130/158)和65.26 μg/kg,4种ENNs的阳性率和平均值分别为ENA:55.1%(87/158)和0.28 μg/kg,ENA₁:8.2%(13/158)和0.62 μg/kg,ENB:3.8%(6/158)和1.19 μg/kg,ENB₁:56.3%(89/158)和0.13 μg/kg。玉米粒、玉米粉和玉米碴中5种毒素的平均值分别为BEA:46.96、86.45和0.17 μg/kg,ENA:0.13、0.35和0.06 μg/kg,ENA₁:0.14、0.76和0.00 μg/kg,ENB:0.23、2.15和0.00 μg/kg,ENB₁:0.21、0.15和0.08 μg/kg。东部地区样品中BEA的污染最严重,其阳性率和平均值分别为87.0%(87/100)和95.75 μg/kg;除南部地区ENA和ENB₁的阳性率较高(均为91.3%,21/23)外,4种ENNs在其他3个地区阳性率均较低,且4种ENNs在4个地区的平均值均低于BEA。结论 山东省部分地区玉米及其制品可受5种六酯肽类真菌毒素的污染,BEA的污染水平高于4种ENNs的污染水平;毒素污染存在种类和地域差异,建议在山东省开展大范围监测的基础上,重点监测东部沿海地区玉米及其制品中BEA的含量。     

Occurrence of enniatins and beauvericin in 60 Chinese medicinal herbs

A total of 60 Chinese medicinal herbs were examined for contamination of the emerging Fusarium mycotoxins enniatins (ENNs) A, A1, B, B1 and beauvericin (BEA). The herbs under study are commonly used in China as both medicines and food. The dried samples of herbs were randomly collected from traditional Chinese medicine stores in Zhejiang province, China. Sample preparation was achieved by methanol extraction, followed by a simple membrane filtration step; no tedious clean-ups were involved. ENNs A, A1, B, B1 and BEA were analysed by the recently developed stable isotope dilution assays, using liquid chromatography-tandem mass spectrometry (LC-MS/MS). With limits of detection ranging between 0.8 and 1.2 µg kg^–1 for the analytes under study, 25% of all analysed samples were contaminated with at least one of the ENNs and BEA. BEA was the most frequently detected toxin with a 20% incidence in all samples. The percentages of ENN-positive samples were lower: each single ENN was detected in 6.7–11.7% of all samples. Considering the total amounts of the five mycotoxins in single samples, values between 2.5 and 751 µg kg^–1 were found. The mean total amount in positive samples was 126 µg kg^–1. Regarding ginger, the frequent occurrence of ENNs and BEA in dried ginger could be confirmed in samples from Germany. However, in fresh ginger root the toxins were not detectable. This is the first report on the presence of ENNs and BEA in Chinese medicinal herbs.     

不同基质中蝉花产白僵菌素研究

目的 将蝉花菌种接种于不同基质培养一定时间后,检测培养物中白僵菌素和恩镰孢菌素含量。方法 将一株蝉花菌种分别接种于4种液体培养基和4种固体培养基中,25 ℃下连续培养1～7周,采用高效液相色谱-串联质谱法测定蝉花培养物中的白僵菌素和恩镰孢菌素。结果 该株蝉花在4种液体培养基上培养不同时间后,白僵菌素的检出率在42.9%～100.0%之间,检出浓度范围为1.0～94.6 μg/L；在4种固体培养基上培养不同时间后,白僵菌素的检出率均为100.0%,检出水平范围在60.9～44 677.5 μg/kg。在4种液体和4种固体培养物中均未检出恩镰孢菌素。结论 该株蝉花在8种试验培养基上培养一定时间后均可产生白僵菌素,且在固体培养基上产生的白僵菌素水平远高于液体培养基,但在两类培养基上均不产生恩镰孢菌素。     

玉米及其制品和小麦及其制品中白僵菌素和恩镰孢菌素的高效液相色谱-串联质谱检测方法的建立

目的建立了玉米及其制品和小麦及其制品中白僵菌素(beauvericin,BEA)、恩镰孢菌素A(enniatin A,ENA)、恩镰孢菌素A_1(enniatin A_1,ENA_1)、恩镰孢菌素B(enniatin B,ENB)和恩镰孢菌素B_1(enniatin B_1,ENB_1)的高效液相色谱-串联质谱检测方法。方法样品经乙腈-水(85∶15,V/V)提取、室温静置、固相萃取柱净化后,以2 mmol/L乙酸铵水-乙腈作为流动相,采用电喷雾电离正离子多反应监测模式进行检测。结果该方法对玉米及其制品和小麦及其制品中BEA和4种恩镰孢菌素(ENNs)的检出限范围分别为0.01~0.12和0.02~0.21μg/kg,定量限范围分别为0.02~0.44和0.05~0.68μg/kg,平均加标回收率范围分别为91.6%~149.7%和100.5%~128.2%,基质抑制或增强效应分别为88.0%~101.5%和55.8%~106.5%,且BEA和4种ENNs在所测基质中线性关系和精密度良好,相关系数均0.99,相对标准偏差均15%。结论所建立的方法操作简便、灵敏度高、准确性好,可用于玉米及其制品和小麦及其制品中BEA和4种ENNs的测定。     

Evaluation of enniatins A,A1, B,B1 and beauvericin in Portuguese cereal-based foods

Sixty-one samples of Portuguese cereal-based foods were analysed for the occurrence of emerging mycotoxins called enniatins (A, A1, B and B1) and beauvericin. Samples were extracted with a mixture of acetonitrile/water (85/15, v/v) using an Ultra-Turrax homogeniser, and mycotoxins were detected with liquid chromatography coupled to a mass spectrometer. This method was validated and adequate values of recovery (70–103%) and relative standard deviation (<15%) were obtained. Signal suppression/enhancement was studied and matrix-matched calibration used to minimise this effect, but no additional clean-up step was necessary. The mass spectrometer was operated in selected reaction monitoring (SRM) mode and with selected transitions for each compound to quantify and to qualify them. Fifty-nine per cent of samples were contaminated. The percentages of enniatins were 53%, 49%, 44% and 16% for A1, B, B1, and A, respectively, and for beauvericin it was 1.6%. For the total samples, the mean contamination was 30, 24, 15, 2.1 and 0.1?ng?g^?1 for enniatins A1, B, B1 and A, and beauvericin, respectively. The wheat-based samples showed higher levels and greater prevalence than any other cereals monitored. These results were used to estimate the daily intake of ENs from wheat-based cereal by the Portuguese population. At the same time, the usefulness of this method in the analysis of other important mycotoxins (aflatoxin B₁, ochratoxin A, deoxynivalenol, T-2 toxin, fumonisin B₁ and zearalenone) was evaluated.     

Presence and concentrations of the Fusarium-related mycotoxins beauvericin, enniatins and moniliformin in finnish grain samples

Fusarium mycotoxins beauvericin, enniatins (A, A1, B, B1) and moniliformin were analysed in 38 Finnish grain samples (14 wheat, 22 barley, one rye, one oats) harvested in 2001-02. The contaminating Fusarium species were identified with the primer-specific polymerase chain reaction as well as with morphological studies. All the studied mycotoxins were found in the samples. Enniatins B and B1 were detected in all samples, and enniatin A, enniatin A1, beauvericin and moniliformin in 74, 95, 95 and 74% of the samples, respectively. There were higher concentrations of the mycotoxins analysed in 2001 compared with 2002. The highest levels of mycotoxins were detected in samples harvested late in the autumn after a long rainy period. Fusarium avenaceum was the most abundant Fusarium species in Finland during both years (0-29.5%) measured as infected kernels. A significant correlation was found between F. avenaceum contamination level and the concentration levels of enniatins B and B1, as well as moniliformin.     

Determination of Fusarium mycotoxins beauvericin and enniatins (A,A1, B,B1) in eggs of laying hens using liquid chromatography–tandem mass spectrometry (LC–MS/MS)

An existing sample preparation technique used for the determination of ionophoric coccidiostats was modified to permit the analysis of Fusarium mycotoxins beauvericin and enniatins in egg samples. The validation results indicated that the sample preparation method developed is well applicable to the determination of the related compounds in eggs. The presence and contamination levels of beauvericin and enniatins A, A1, B and B1 were studied in Finnish egg samples in 2004–2005. The egg sample analyses (112 whole eggs and 367 egg yolk) revealed that the occurrence of beauvericin as well as enniatins B and B1 is very common in Finnish eggs. The contaminations were, however, in most cases in trace-levels (<limit of quantification). Enniatin A and A1 were not found in any of the whole egg samples, and furthermore enniatin B1 was present only in samples from 2004. The general contamination levels of beauvericin and enniatins in whole egg samples were similar in 2004 and 2005. The prevalence and concentration levels of mycotoxins were higher in the market samples (egg yolk) as compared to samples collected in the national residue monitoring programme (whole egg) samples suggesting that there may be bioaccumulation of these mycotoxin contaminants in egg yolk. This is the first study to report the presence of Fusarium mycotoxins beauvericin and enniatins in egg samples.