【作者】 王燕；

【导师】 赵善仓； 李大鹏；

【作者基本信息】 山东农业大学 ， 食品科学， 2016， 硕士

【摘要】 真菌毒素是由产毒真菌在新陈代谢过程中产生的次级活性代谢产物,部分具有致癌、致畸和致突变的作用。玉米是世界第一大农作物,2015年我国玉米总产量约为2.197亿吨,除一部分作为粮食和食品加工外,约70%用作饲料。目前,玉米真菌毒素污染问题已成为世界各国高度关注的食品安全热点问题。受气候条件和储藏条件等因素的影响,每年山东受真菌毒素污染造成的粮油损失累计约3100万吨,因此开展山东省玉米真菌毒素检测技术和污染状况研究对于保障山东省粮食安全具有重要的现实意义。本研究以山东省为检测区域,在2013年度-2014年度采集了山东省13个玉米主产县收获期和储藏期共520批次玉米样品,分析了影响玉米质量安全的几种主要真菌毒素(玉米赤霉烯酮、黄曲霉毒素、伏马毒素和脱氧雪腐镰刀菌烯醇)的危害及当前的限量标准,检测了玉米中黄曲霉毒素B1、黄曲霉毒素B2、黄曲霉毒素G1、黄曲霉毒素G2、伏马毒素B1、伏马毒素B2、伏马毒素B3、脱氧雪腐镰刀菌烯醇和玉米赤霉烯酮9种真菌毒素的污染水平,提出了保障玉米质量安全的建议和对策,为掌握山东省玉米的真菌毒素污染状况,评估污染带来的安全风险提供了数据支撑。主要研究方法及结果如下：1.建立了基于分散型固相萃取法结合液相色谱-飞行时间质谱联用仪方法同时检测玉米中黄曲霉毒素B1、黄曲霉毒素B2、黄曲霉毒素G1、黄曲霉毒素G2、伏马毒素B1、伏马毒素B2、伏马毒素B3、脱氧雪腐镰刀菌烯醇和玉米赤霉烯酮等9种真菌毒素的分析方法。样品经乙腈/水提取液(84/16,V/V,含1%冰乙酸)提取,C18净化剂净化后,提取液经氮吹干后用甲醇/水(5/5,V/V)复溶,再采用电喷雾正离子模式(ESI+)进行检测,以保留时间和精确分子质量数定性,以TOF MS提取离子的峰面积定量。(1)9种真菌毒素的质量精确度均小于4ppm,相关系数R2均大于0.99,回收率为68.0%-120.0%之间,相对标准偏差在0.18%-6.29%之间,均小于10%。(2)最低检出限分别为黄曲霉毒素B1 (0.05μg/kg)、黄曲霉毒素B2 (0.05μg/kg)、黄曲霉毒素G1 (0.05μg/kg)、黄曲霉毒素G2 (0.05μg/kg)、伏马毒素B1 (5μg/kg)、伏马毒素B2 (5μg/kg)、伏马毒素B3 (5μg/kg)、玉米赤霉烯酮(12μg/kg)、脱氧雪腐镰刀菌烯醇50μg/kg)(3)定量限分别为黄曲霉毒素B1 (0.1μg/kg)、黄曲霉毒素B2 (0.1μg/kg)、黄曲霉毒素G1 (0.1μg/kg)、黄曲霉毒素G2 (0.1μg/kg)、伏马毒素B1 (15μg/kg)、伏马毒素B2(15μg/kg)、伏马毒素B3(15μg/kg)、玉米赤霉烯酮(25μg/kg)、脱氧雪腐镰刀菌烯醇(200μg/kg)。综上所述,表明该检测方法具有更快捷、更准确、节约时间和成本的优点,适用于日常玉米中真菌毒素含量的检测。2.采用上述方法对山东省玉米13个主产县2013年度-2014年度收获期和储藏期共520批次玉米样品进行检测。(1)黄曲霉毒素B1、黄曲霉毒素B2、黄曲霉毒素G1在玉米中检出率和平均含量分别为18.08%、7.62μg/kg;7.88%、0.60μg/kg;0.77%、0.05μg/kg;而黄曲霉毒素G2均为未检出；伏马毒素B1、伏马毒素B2、伏马毒素B3为92.50%、1798.69μg/kg;88.08%、 531.83μg/kg;83.85%、197.71μg/kg;脱氧雪腐镰刀菌烯醇为26.35%、240.44μg/kg;玉米赤霉烯酮为14.62%、74.90μg/kg。(2)调查结果还表明伏马毒素在所测样品中污染最为严重,超标率达33.46%。更多还原

【Abstract】 Mycotoxins are secondary metabolites produced by micro-fungi, some of which are carcinogenic, teratogenic, mutagenic. The plant area of corn is the largest in the whole world, and corn’s production was about 219.7 million tons in 2015 in China. In addition, about 70% was used as feed. At present, contamination of mycotoxins in corn was paid increasing attention and became the hot issue in food safety area. Due to climate and storage methods,31 million tons of grain contaminated by mycotoxins every year in Shandong province. So it is important to investigate the detection technology and pollution research of corn in Shandong province.This paper took Shandong for example to investigate the main cause and the harm of the risk factors that affect the quality and safety of corn, and offered several suggestions to guarantee the quality and safety control of corn. To study the contamination of mycotoxins of corn, assess the security risks of pollution, and provide the basis for strengthening the prevention and control of mycotoxin contamination in Shandong Province, the study analyzed the 9 kinds of mycotoxins such as aflatoxin(AFB1, AFB2, AFG1, AFG2), fumonisins(FB1, FB2, FB3), deoxynivalenol and zearalenone in corn contaminations.The main research methods and results were as follows:1. A fast analytical method for the simultaneous determination of 9 toxicological important mycotoxins, such as AFB1, AFB2, AFG1 and AFG2; FB1, FB2 and FB3; ZON and DON in corn using a novel Dispersive Solid-Phase Extraction (DSPE) method and Ultra-performance LC coupled to tandem quadrupole TOF-MS (UPLC-Q-TOF/MS) was developed and validated. Samples were extracted with acetonitrile-water (84:16 v/v, containing 1% acetic acid) by means of ultrasonic extraction. The extract was purified with a novel modified dSPE method. The final clear extracts were blew to near dryness under nitrogen and redissolved with MeOH:H2O (5/5, V/V). And then analyzed by LC-ESI-MS on a Thermo Hypersll GOLD C18 column with 0.1% formic acid in ammonium acetate/methanol as mobile phase with gradient elution. Mycotoxins were identified by the retention time and the accurate molecular mass number and the quantification of mycotoxins was carried out by TOF MS extract ion peak area.(1) The results indicated that the quality of 9 kinds of fungus toxin accuracy are less than 4ppm, correlation coefficient R2 were greater than 0.99, and the mean recoveries were ranged from 68.0% to 120.0% and RSDs ranged from 0.18% to 6.29% that were all less than 10%.(2) Limits of detections (LODs) of the 9 mycotoxins were AFB1 (0.05μg/kg)、AFB2 (0.05μg/kg)、AFG1 (0.05μg/kg)、AFG2 (0.05μg/kg)、FB1(5μg/kg)、FB2 (5μg/kg)、FB3 (5μg/kg)、ZON (12μg/kg)、DON (50μg/kg), respectively.(3) The limits of quantification (LOQs) of the 9 mycotoxins were AFB1 (0.1μg/kg)、 AFB2 (0.1μg/kg)、AFG1 (0.1μg/kg)、AFG2 (0.1μg/kg)、FB1 (15μg/kg)、FB2 (15μg/kg)、FB3 (15μg/kg)、ZON (25μg/kg)、DON (200μg/kg), respectively.The results showed that method had the characteristics of efficient, accurate, time-saving, and it is suitable for the daily detection of mycotoxins in corn.2. The developed method was applied to 520 corn samples and the results showed that:(1) 18.08% of the corn samples were contaminated with AFB1,7.88% with AFB2,0.77% with AFG1,92.50% with FB1,88.08% with FB2,83.85% with FB3,26.35% with DON, 14.62% with ZON, whereas none of corn samples was contaminated with AFG2. The average concentrations of AFB1, AFB2, AFG1,FB1, FB2, FB3, DON and ZON were 7.62μg/kg, 0.60μg/kg,0.05μg/kg,1798.69μg/kg,531.83μg/kg,197.71μg/kg,240.44μg/kg,74.90μg/kg, respectively.(2) In addition, the results indicated that FUN contamination in corn was one of the most severe problem. The over standard rate was 33.46%.更多还原