【作者】 秦红梅；

【导师】 金一和；

【作者基本信息】 中国医科大学 ， 卫生毒理学， 2003， 硕士

【摘要】 目的 3-氯-1，2-丙二醇(3-monochloropropane-1，2-diol，3-MCPD)，属氯丙醇类化合物，因其污染广泛、污染的产品中有不少涉及国际贸易，近年来受到各国卫生学者的重视。3-MCPD是确认的人类致癌物，具有生殖毒性、神经毒性、且能引起肾脏肿瘤。FAO&WHO联合专家委员会(JECFA)暂定2μg／Kg bw为3-MCPD每日最大耐受摄入量。 3-MCPD在食品的加工和贮藏过程中均可产生。水解蛋白调味剂和酱油中3-MCPD含量最多。目前，国外采用毛细管色谱法和气相色谱-质谱(GC-MS)测定酱油中3-MCPD。而我国在此方面研究较少，在我省尚未开展酱油中3-MCPD的GC-MS检测。 本研究旨在建立用气相色谱-质谱联用仪检测酱油中3-MCPD的方法。并在此基础上对市售酱油样品进行检测，以了解3-MCPD在酱油食品中的污染状况，并进行卫生学评价，为我国酱油食品的卫生监督管理和卫生标准的制定提供科学依据。 材料与方法 1．样品 采自辽宁、吉林、山东省内超市和农贸市场上销售的产地包括上海＊京、广州、沈阳、长春等23个城市和地区的酱油样品60份。 2．仪器和试剂 Hp－5972 GC－MS气质联用仪、Hp－SM．S．色谱柱、3－MCPD、苯基硼酸等。 3．实验方法 3．l 样品处理 取样品sml，置于 10Inl代塞的试管中，加人 1．OInl苯基硼酸衍生化试剂，摇匀，置于90℃恒温箱中，反应20分钟，停止加热，冷却至室温后，加入3．OInl正己烷，震动1分钟，静置后，取革取液用于 GC－MS分析。 3．2 3－MCPD标准曲线：分别取0．10，0．50，二．00，10．00，100．00mg／L标准溶液。进行衍生化处理。同时做空白。制作3－MCPD标准曲线。 3．3 GC—MS分析条件 3．3．l 气相色谱参数HP5890气相色谱仪，色谱柱HP－SM．S．高纯氦气载气，流量为0．600rnl／ndn。进样口温度250t。色谱柱程序升温，100Tp，升温速度10t／dn，230t（smin）。 3．3．2 质谱参数 气相色谱一质谱联用仪SI离子源，电子能量70eV，传输线温度240℃，电子倍增器电压2059V，扫描方式SIM m／Z147，以 In／Z147作为3－MCPD定量离子。 3．4 测定 取样品溶液M 进样，记录 3－MCPD的峰面积，绘制标准曲线，外标法计算样品中3－MCPD含量。 3．5 方法的精密度和准确度 选未检出3－MCPD的市售酱油为本底分别进行3次加标回 ·2·收实验。精密度以相对偏差（RSD％）表示，准确度以相对回收率（P％）表示。 3．6 数据处理 用EXCEL石PSS软件进行实验数据统计分析。 实验结果 1．对3－MCPD标准品溶液苯基硼酸衍生物进行全离子扫描，3－MCPD峰的保留时间为9．Zmin。全离子扫描基峰为In／2147，选择ndZ147进行SIM法测定酱油样品中3—MCPD。 2．线形范围、重现性和最低检测下限 将标准溶液配置成浓度0．1－100mg／L的标准系列，进样测定。峰面积和 3－MCPD浓度程良好的线性关系，r＝0．999879，P＜0．001。最低检测下限为 0．09＜giL。回收率为 105．9％，相对标准偏差为 5．90％。 3．酱油样品检测结果 3－MCPD在酱油样品中的浓度范围是0－ZI．sin吵L，3－MCPD浓度从0到ZI．sing／L，90物的酱油3－MCPD含量符合我国行业标准（＜1．om砂L厂8．3％介于lin矿L和10 m矿L之间，1．67％大于10 m矿L，最大超标倍数约为22倍。 4．样品中酿造酱油、配制酱油、未标明分类的酱油的超标率分别为5．7％，33．3％和50．0％。各类酱油中之间的超标率差异具有统计学意义。 讨 论 3－MCPD属于氯丙醇类化合物，氯丙醇类化合物包括2一氯1，3一丙H醇、1，3－H氯一2一丙醇和2，3－H氯一1一丙醇等。3 ·3·－MCPD的大鼠经口 LD。。为150 m才巨，经消化道吸收，随血液分布于机体各组织脏器中，可以通过血睾屏障和血脑屏障。3－MCPD与谷航甘肽结合形成硫醚氨酸后毒性降低。在体内大约30％的3－MCPD可以被分解，并以CO。形式呼出体外。3－MCPD是确认的人类致癌物，具有生殖毒性、神经毒性、且能引起肾脏肿瘤。FAO＆WHO联合专家委员会暂定3－MCPD每日最大耐受摄人量是2卜g／Kg bw。 目前国际上主要用 GC－MS／SIM方法检测 3－MCPD。2001年国际分析家协会（AOAC）推荐将样品经层析用七氟了酸基咪哩衍生，用气相色谱一质谱连用仪离子选择检测方法（GC－MS／SIM）进行测定。其特点是特异性好、灵敏度高、最低检测浓度可达到 0．of m矿L，但样品前处理过程比较繁琐。本研究改变了对酱油的处理过程，直接用苯基硼酸进行衍生化，正己烷抽提，用 GC－MS亿IM方法测定。本研究采用色谱柱程序升温100℃e 火升温速度10℃／min，至230℃K 人质谱采用选择基峰离子m／z147进行测定，提高了分辨率。在3－MCPD标准溶液浓度0．1－100．00 m牙L范围内，3－MCPD浓度与色谱峰面积呈良好的?更多还原

【Abstract】 3 - chloro - 1,2 - propanediol (3 - MCPD) is one of a group of chemical contaminants known as chloropropanols. Recently, many experts pay more attention to 3 - MCPD because of its wide contamination . According to the Joint FAO/WHO Expert Committee on Food Additives (JECFA) , 3 - MCPD has reproduction toxicity , nerve toxic-ity, and carcinogenisis. JECFA established a provisional maximum tolerable daily intake of 2jxg/Kg bw for 3 - MCPD . 3 - MCPD can be developed in food processing and storage. Levels of 3 - MCPD in acid - HVP and soy sauce are significantly higher than in other foods.At present , Capillary Chromatography and Gas Chromatography with Mass spectrometric detections are adopted to detect 3 - MCPD a-broad. However, researches in this area are scarce in China, and the 3 - MCPD detect method by GC - MS is not yet carried out in Liaoning province.This study was designed to establish analytical method for determination of 3 - MCPD in soy sauce by GS - MS. Basing on the meth-od, we examined 3 - MCPD of soy sauce in market, investigating the contamination of soy sauce by 3 - MCPD and evaluating them. Finally , to provide scientific basis for establishing sanitary standard and inspecting soy sauce.Materials and Methods1. Samples60 soy sauce samples were purchased from supermarket and other retail outlets in Liaoning ,Jilin and Shandong province , where manufactories include Beijing , Shanghai, Guangzhou as well as other twenty - three cities and regions in China.2. Apparatus and reagentsMass spectrometer with gas chromatograph GC - MS Hp - 5972, Hp-5ms,3 -MCPD, Phenylboronic acid,etc.3. Experimental method3. 1 Treatment of samplesAdd 5 ml of sample into 10 ml test tube with cap , thoroughly mix with 1.0ml 25% Phenylboronic acid. Put the tube into constant temperature oven at 90 癈 , react for 20 min. Allow the mixture to cool at room temperature and add 3 ml Skellysolve B. Shake for 1 min, allow the phases to separate. Stand for a "while , then transfer the Skellysolve B phase for GC - MS.3.2 3 - MCPD Standard curveSerial standard solutions were got with concentrations of 0.10, 1. 00,10.00,100.00mg/l, including blank. Derivated standard solutions . Use 1 ul to make standard curve of 3 - MCPD3. 3 Analysis condition of GC - MS3.3.1 Operation conditions for Gas Chromatography Samples were separated on a 30m X 0. 25mmi. d. DB5MS column each with a 0. 25u,m film thickness. GC temperature program: 2min at 100℃;, 10℃/min to 230℃ ,hold for 5min; injections 250℃; Helium carrier at 0. 600ml/min;3.3.2 Operation conditions for MSGeneral: HP 5972; transfer line temp 240℃; electronic ion source; electronic power 70eV; mutiplier voltage 2059V; selected ion monitoring mode m/z147.3.4 DeterminationSamples are to be injected 1ul once using the conditions above. Measure the areas of 3 - MCPD . Draw standard curve. 3 - MCPD is calculated by the external standard method.3.5 Precision and recoverySamples with no 3 - MCPD as background are added 3 - MCPD , undertaken recovery test for 3 times. RSD% represents precision, while P% represents recovery.3. 6 Data processingUse EXCEL and SPSS to analyse data.Results1. Full scan El 3 - MCPD derivatives. Peak of 3 - MCPD occurs at 9. 2 min( retention time) . Diagnostic ion peak is m/z147. Detect soy sauce samples with SIM m/z147.2. Scope, repeatability and limit of detectionWith the concentration ranging from 0. 10 - 100. 00 mg/L, the standard 3 - MCPD has a nice linear relationship with the area ofchromatographic peak, and the correlation index is 0. 999879. The lowest limitation of determination is 0. 09 mg/L. Recovery is 105. 9% , relative standard error is 5.90%.3. SamplesConcentration of 3 - MCPD in samples varys from 0 to 21. 8mg/ L. 90% of soy sauce are in line with national standard ( < 1.0mg/ L). The highest level is about 22 times of the standard. 1.67% of the samples are more than 10 mg/L while 8.3% of samples are between 1更多还原