基于抗氧化效果的银杏叶活性成分提取工艺优化及其抗氧化活性的评价的开题报告.docx

基于抗氧化效果的银杏叶活性成分提取工艺优化及其抗氧化活性的评价的开题报告 摘 要 本文研究的对象为银杏叶中的活性成分，初步确定为黄酮类物质和三萜类物质。本研究使用水提、醇提及超声波辅助提取工艺分别对银杏叶的活性成分进行提取，并对提取工艺进行了优化。同时，对提取液的抗氧化活性进行了评价。 基于筛选实验结果，以水为溶剂，提取温度为90℃，提取时间为2小时，提取液的浓度为4g/mL时，水提法提取活性物质的产率最高。同时，以乙醇为溶剂，提取温度为70℃，提取时间为1小时，提取液的浓度为3g/mL时，醇提法提取活性物质的产率最高。最后，采用超声波辅助提取法进行提取，发现该方法提取效果较好，但在过高的超声波功率和时间下，可能会导致部分活性成分的破坏，因此需对超声波的功率和时间进行适当的调整。经过对三种提取方法的比较，发现水提法得到的银杏叶提取物的抗氧化活性最好，可能与水提法提取出的黄酮类物质有关。 关键词：银杏叶；活性成分；提取工艺；抗氧化活性 Abstract The object of this study is the active ingredients in Ginkgo biloba leaves, which were preliminarily identified as flavonoids and triterpenoids. Water extraction, alcohol extraction and ultrasound-assisted extraction were used to extract the active ingredients from Ginkgo biloba leaves, and the extraction process was optimized. Meanwhile, the antioxidant activity of the extraction solution was evaluated. Based on the results of screening experiments, the highest yield of active substances extracted by water extraction was obtained using water as the solvent, extraction temperature of 90℃, extraction time of 2 hours, and extraction solution concentration of 4g/mL. At the same time, the highest yield of active substances extracted by alcohol extraction was obtained using ethanol as the solvent, extraction temperature of 70℃, extraction time of 1 hour, and extraction solution concentration of 3g/mL. Finally, ultrasound-assisted extraction was used, and the results showed that this method had a good extraction effect, but excessively high ultrasound power and time may lead to the destruction of some active ingredients, so the ultrasound power and time need to be adjusted properly. Through the comparison of the three extraction methods, it was found that the water extraction method obtained the best antioxidant activity of Ginkgo biloba leaf extract, which may be related to the flavonoids extracted by water extraction method. Keywords: Ginkgo biloba leaves; active ingredients; extraction process; antioxidant activity