八月瓜果皮总三萜的分离分析研究

发布时间：2018-04-02 22:06

  本文选题：八月瓜　切入点：总三萜　出处：《吉首大学》2017年硕士论文

【摘要】：八月瓜是木质藤本半常绿缠绕植物,含有丰富的黄酮、多酚、微量元素以及齐墩果酸和熊果苷等三萜化合物,广泛用于医药、食品、化妆品等领域。本文以湘西八月瓜为研究原料,分别探索了八月瓜果皮中总三萜的紫外可见分光光谱分析方法、超声波水解提取八月瓜果皮总三萜的工艺条件、大孔树脂吸附总三萜的动力学和热力学研究以及响应面优化大孔树脂吸附分离总三萜的分离工艺。以八月瓜果皮干粉为研究原料,80%乙醇溶液作为提取剂,采用超声波辅助法提取果皮中的总三萜,建立一种紫外可见分光光度法测定提取液中总三萜的分析方法。用香草醛-高氯酸作为显色剂,545 nm处作为测定波长,进行比色条件优化和方法学考察。结果表明,加入0.20 mL八月瓜果皮供试品溶液,放置水浴锅加热,至溶剂挥发完毕,随后分别加入0.30 mL现配置的5%香草醛-冰醋酸溶液和0.70mL高氯酸,在70℃条件下保持15 min,显色效果最佳。八月瓜果皮提取液中总三萜的平均回收率为101.1%,RSD值为1.2%。该方法快速、准确,重复性好,且用该方法测得的果皮总三萜含量与高效液相色谱法测得结果吻合。采用超声波辅助-水解法提取八月瓜果皮中的总三萜,通过单因素实验和响应面优化试验考察了pH值、温度、时间对果皮总三萜提取率的影响。结果表明,优化提取工艺参数为:pH值为5.6,提取温度为71℃,提取时间103 min,总三萜的提取率为97.2%。从7种商用大孔树脂中筛选出XDA-1型大孔树脂吸附分离八月瓜果皮中的总三萜,探讨了XDA-1型大孔树脂对八月瓜果皮总三萜的吸附特性;根据Van’t Hoff方程,研究吸附热力学参数。动力学研究表明,XDA-1大孔树脂对八月瓜果皮总三萜的吸附符合准二级动力学方程描述;热力学研究表明,XDA-1大孔树脂对八月瓜果皮总三萜的吸附符合Freundlich等温吸附方程。吸附焓变ΔH0,表明XDA-1型大孔树脂对八月瓜果皮总三萜的吸附过程为放热过程,且|ΔH|43 k J/mol,说明吸附过程为物理吸附过程;吉布斯自由能ΔG0表明吸附过程是自发的;吸附熵变ΔS0,表明该吸附是一个伴有熵值增加的过程。研究了XDA-1型大孔树脂分离八月瓜果皮中的总三萜。以固液比、吸附温度、吸附时间为单因素,用响应面优化法考察了这三个因素对总三萜提取率的影响。结果表明,在固液比为1:8 g/mL,40℃温度下吸附315 min,总三萜的得率为63.53%,试验结果与模型预测值吻合。
[Abstract]:Melon is a woody vine semi-evergreen twining plant, rich in flavonoids, polyphenols, trace elements, oleanolic acid and arbutin and other triterpenoids, widely used in medicine, food, cosmetics and other fields.In this paper, the ultraviolet visible spectrophotometric analysis method of total triterpenoids in the peel of Euphorbia indica L. was studied, and the technological conditions of ultrasonic hydrolysis and extraction of total triterpenoids from the peel of Euphorbia melons were studied.The kinetics and thermodynamics of macroporous resin adsorption of total triterpenoids and the optimization of the process of macroporous resin adsorption and separation of total triterpenoids were studied.The total triterpenoids were extracted from the pericarp by ultrasonic assisted extraction with 80% ethanol solution as the raw material. A method was established for the determination of total triterpenoids in the extract by ultraviolet visible spectrophotometry.Vanillin perchloric acid was used as chromogenic agent at 545 nm as the determination wavelength to optimize the colorimetric conditions and investigate the methodology.The results showed that 0.20 mL fruit peel solution was added and heated in a water bath pot until the solvent was volatilized. Then 0.30 mL vanillin glacial acetic acid solution and 0.70mL perchloric acid were added respectively.At 70 鈩，

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