【作者】 曹柏营；

【导师】 欧仕益；

【作者基本信息】 暨南大学 ， 食品科学， 2006， 硕士

【摘要】 转基因食品的安全性得到全球的普遍关注。鉴于抗草甘膦转基因大豆导入基因表达的5-烯醇丙酮酸莽草酸-3-磷酸合酶控制的主要是植物次生代谢产物酚类和生物碱，本论文以大豆次生代谢产物酚类物质为主要研究对象，采用高效液相色谱法研究了转基因大豆及其亲本和2个常规品种中的酚类物质；同时，采用气相色谱法和SDS-聚丙烯酰胺凝胶电泳法分别分析了大豆油脂中的脂肪酸组成与籽粒蛋白中蛋白质分子量的差异，得出以下结论： 1．大孔树脂分离纯化大豆酚类物质，阴离子树脂分离纯化大豆酚酸类物质都能达到理想的分离纯化效果。抗草甘膦转基因大豆及其亲本和常规大豆品种的酚类物质在种类和含量上存在差别，采用HPLC测定不同大豆材料时都表现出特定图谱，且这种差别同时存在于大豆籽粒的不同分离组分中。 2．大豆在导入EPSP合酶的外源基因后，对大豆油脂中的脂肪酸含量有所影响，抗草甘膦转基因大豆的脂肪酸含量比非转基因大豆的低，但脂肪酸的种类没有太大的差异；大豆油脂用乙醇水溶液提取酚类物质后其脂肪酸组成没有明显的变化，但脂肪酸的含量减少，且非转基因大豆减少的趋势比较明显。 3．转基因大豆与非转基因大豆蛋白质组成存在差异，转基因大豆中出现了40KDa的特殊蛋白质。 抗草甘膦转基因大豆与其亲本和两个常规品种在多酚种类和含量上存在差异，说明采用酚类HPLC图谱法可用于鉴定不同大豆品种及其制品的来源，包括转基因大豆。这些初步研究结果有可能为转基因大豆鉴定找到一条直接、简便的方法，同时为评价转基因大豆的安全性开辟新的研究领域。更多还原

【Abstract】 The safety of genetically modified soybean (mainly Roundup Ready soybean) aroused worldwide concern and much work on its safety evaluation was carried out in recent years. Glyphosate-tolerant soybean (RR soybean) is a soybean variety introduced an exogenous gene which controls expression of 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS). EPSPS is a key enzyme in secondary metabolism that would affect phenolic substances metabolism, suggesting that changes in metabolism of phenolic substances would occur comparing with its parent. In this research, phenolic substances were investigated in different fractions of soybean seed from transgenic soybean and its parent, and two conventional varieties. Furthermore, the content and composition of seed fatty acids and protein were also comparatively studied by GC and SDS-polyacrylamide gel electrophoresis respectively. The main results were as follows.1. The phenolic substances were extracted and purified from soybean seeds with an AB-8 macroporous resin column, and phenolic acids were extracted and purified from defatted soybean powder with anion- exchange resin column, which were all tested by HPLC. The results showed that there were significant differences in composition and content of phenolic substances between the tested materials, including RR soybean and its parent. The differences could be found in different fractions of seeds, including oil, protein and pulp.2. There were significant differences in content of fatty acids between the tested materials, but no difference was observed for the composition of fatty acids, indicating that genetically-modification in soybean would quantitatively but not qualitatively affect metabolism of fatty acids.3. Protein composition of soybean seed protein changed after genetically-modification, the RR soybean had a special protein band with molecular weight of 40KD.更多还原