烟草中几类致香物质的色谱—质谱联用分析研究

【作者】 李苇苇；

【导师】 陈晓青；

【作者基本信息】 中南大学 ， 分析化学， 2010， 硕士

【摘要】 烟草香味是评价烟草质量的一个重要指标,因此研究烟草中的致香成分对于提高烟草品质、监控卷烟质量具有重要的意义。但是在卷烟的生产、加工和储存过程中,许多常规香精香料均存在挥发性强、易升华和留香不持久等问题,对卷烟产品的风格及质量稳定不利。而潜香物质的应用是一个很好的解决途径,潜香物质的开发和应用是目前烟草香精香料研究的一个重要内容。因此,有必要对烟草中的潜香物质进行系统研究,更多的了解这些物质,使之更加充分的发挥作用。本论文的研究内容主要有四个方面：1.烟草挥发油的提取及气相色谱-质谱(GC-MS)分析。同时蒸馏萃取法提取香料烟和烤烟的挥发油,用GC-MS对其进行检测,并对两种烟叶的挥发油进行比较。分别鉴定出45和42种化合物,占精油总量的89.4%和93.7%。两种挥发油主要成分为烷烃类、酸类、醛酮类、醇类和烯类,共有13种物质完全相同。2.糖苷、糖酯的提取和分离纯化。以糖苷和糖酯的得率为指标,分别对两类物质的提取溶剂、时间、料液比和提取次数进行考察,得到最佳的提取条件。并用AmberliteXAD-2和Sephadex LH-20树脂柱对两类物质进行初步分离提纯。3.糖苷、糖酯的高效液相色谱-质谱联用(HPLC-ESI-MS)分析。以甲醇和水为流动相,采用高效液相色谱-质谱法分析烟草提取物中5种糖苷类化合物,得到五种物质的分子量信息,并用电喷雾质谱(ESI-MSn)对糖苷的结构进行进行了进一步研究；HPLC-ESI-MS联用技术对香料烟烟叶中糖酯类物质进行了分离分析,初步鉴定出7种糖酯,同时也对其分子结构进行初步分析。4.糖苷、糖酯的裂解-气相色谱-质谱(PY-GC-MS)研究。模拟吸烟过程,在特定温度下对烟草提取物快速裂解采样,采用在线PY-GC-MS技术,对烟草糖苷、糖酯的热裂解行为进行了研究,并分析了裂解过程中产生的主要致香成分。更多还原

【Abstract】 The aroma of tobacco is one of the most important factors in evaluation of it quality, so the research of tobacco aroma constituents for improving and monitoring the quality of cigarette is significant. Because conventional flavors are easy to volatile and sublimation, fragrance can not last long, which is great disadvantage for keeping the style and quality of tobacco in its production, processing and storage. Flavor precursors can solve this problem. The development and application of flavor precursors are an important part in the study of tobacco flavors. Therefore, it is necessary to research these substances, learn more about these substances, and make it full use in tobacco. Following four investigations of work were done.1. Extraction and GC-MS analysis of essential oil. Volatile oil of spice tobacco and flue-cured tobacco are obtained by simultaneous distillation-solvent extraction. Following, the essential oil is analyzed by gas chromatography-mass spectrometry.45 and 42 components in two kinds of essential oil were identified separately, constituting approximately 89.4% and 93.7% of the oil. The main components of volatile oil are hydrocarbons, acids, aldehydes, ketones, alcohols and alkenes. Totally,13 kinds of compounds of two essential oils are identical.2. Extraction and Purification of the glycosides and sucrose esters. Based on the amount of extracted glycosides and sucrose esters, we studied the extraction solvent, time, solid to liquid ratio and extraction times, at last obtained the best extraction conditions. After extraction, glycosides were efficiently separated by chromatography on AmberliteXAD-2 column, and sucrose esters were well separated by SephadexLH-20 resin column.3. Liquid chromatography-mass spectrometry analysis of glycosides and sucrose esters. With high performance liquid chromatography-mass spectrometry(LC-MS), five glycosides were well separated on C18 column with mixtures of methanol and water as mobile phase, and the molecular weight of five glycosides were obtain simultaneously. The structures of the glycosides were further studied by ESI-MSn; the sucrose esters were studied by LC-MS, accurate molecular weights were determined through ESI-MS on-line detection, and fragment of sucrose esters were obtained by off-line analysis.4. Pyrolysis-gas chromatography-mass spectrometry analysis of glycosides and sucrose esters. Simulated smoking process, glycosides and sucrose esters were studied on their thermolysis with a pyrolyser connected directly to a gas chromatograph in specific temperature, and analyzed the flavor and fragrance that the glycosides and sucrose esters produced after the thermolysis.更多还原