【作者】 何晓晗；

【导师】 纪淑娟；

【作者基本信息】 沈阳农业大学 ， 食品科学， 2004， 硕士

【摘要】 仲丁胺（2-aminobutane，简称2-AB）是一种保护性杀菌剂，对多种真菌有抗菌活性，广泛应用于柑桔、苹果、梨、桃、香蕉、马铃薯、青椒等果品蔬菜贮藏期的防腐保鲜。由于2-AB不能用分光光度计进行直接检测，同时果蔬样品中含有其他低级脂肪胺干扰测定。所以针对上述问题本文分别采取待测物衍生和薄层色谱分离的办法，通过对衍生条件与薄层色谱分离条件以及分离后定量分析方法的筛选，确定了薄层色谱法检测果品蔬菜中仲丁胺残留量的操作过程如下：取一定量样品匀浆→加入75ml lmol／LCaCl₂溶液，10g MgO加150ml蒸馏水→水蒸汽蒸馏→用装有10ml 0.15mol／L H₂SO₄溶液的量筒接收馏出液约80ml→用0.3 mol／L NaOH溶液将蒸馏液调到pH7→用蒸馏水定容至100ml→吸取样品溶液10 ml于125ml梨形分液漏斗中→分别用15ml四氯化碳洗涤三次→转至50ml具塞锥形瓶中→加入5ml硼酸盐缓冲液和2ml DNFB试剂置60℃水浴反应30min→加入2ml 2mol／L NaOH溶液继续恒温30min→冰浴冷却→用10ml环己烷萃取，并弃去水层→再用15ml 0.05mol／L Na₂CO₃溶液洗涤共三次→加入2g无水Na₂SO₄脱水→旋转蒸发至干→0.2ml苯溶解→将50μl上述溶液点于硅胶薄层板→用正己烷-乙醚（70：30）展开→以三氯甲烷洗脱斑点并定容至5ml→于332nm处测吸光度。为保持一致的操作条件，系列标准溶液采用同样的衍生、薄层色谱分离和定量分析方法，绘制标准曲线。该检测方法的综合评价结果表明，其线性范围为1.25～25μg，回归方程为Y=0.0121X-0.0071，相关系数为R²=0.9945，最低检出量为1μg，对青椒、蒜苔、柑桔、葡萄检测的回收率分别为101.2％、89.2％、88.5％、85.7％，RSD分别为7.9％、5.4％、7.7％、4.1％。更多还原

【Abstract】 2-AB is a kind of protective fungicide that is effective to a range of fungi. It is a preservative that is widely used in the storage of the orange, apple, pear, peach, banana, potato, green pepper etc. It is difficult to detect the residue of 2-AB by UV detector directly. The other low molecular weight aliphatic amines in some fruit and vegetables will interfere the detecting. To get an accurate result, it is necessary to convert 2-AB into its derivative by reaction between 2-AB and DNFB, and to separate 2-AB derivative from other derivatives by thin layer chromatography. In this paper, the conditions of deriving, TLC and quantitative analysis were studied. The selected procedures for detection of 2-AB residue in fruit and vegetables are as follows: take some slurry → add 75ml 1 mol/L CaCl2, 10g MgO and 150ml distilled water → distill with vapor → receive 80ml distillate fraction with 10ml 0.15 mol/L H2SO4 → adjust pH to 7 with 0.3 mol/L NaOH → dilute to 100ml with distilled water → get sample solution→ take 10ml sample solution into 50ml separatory funnel → extract with 15ml carbon tetrachloride for three times → transfer into 50ml conical flask with plug → add 5ml borate buffer liquid and 2ml DNFB, keep in water bath at 60 ℃ for 30 min → add 2ml 2mol/L NaOH and keep for another 30 min →cool with ice bath → extract with cyclohexane and discard water layer → wash with 15ml 0.05mol/L Na2CO3 for three times→ add 2g Na2SO4 without water to dehydrate → vaporize to dryness → resolve in 0.2ml benzene → spot 50ul solution on thin layer → spread with hexane: ether (70:30) → wash the 2-AB spot with chloroform and to make up to 5ml → detect under 332nm. A series of 2- AB standard solution are derived, separated and quantitative analyzed at same conditions with same methods. Using this method, the content of 2-AB haswonderful liner relationship with its absorbance value, the regress equation is Y=0.0121X-0.0071, R2=0.9945, the liner range is 1.25~25ng, the lowest detecting amount on thin layer is l(ig. The detection of some fruits and vegetables shows that the recoverage for pepper, garlic bolt, orange and grape are 101.2%, 88.5%, 85.7% and 89.2%, respectively, and the RSD for them are 7.9%, 5.4%, 7.7% and 4.1%, respectively.更多还原