摘 要：多酚类化合物是银杏外种皮中最重要的有效成分之一，其化合物具有抗氧化、强化血管壁、促进肠胃消化、降低血脂肪、增加身体抵抗力、防止动脉硬化及血栓形成等作用；还有利尿、降血压、帮助消化、抑制细菌与癌细胞生长等功效，尤以对心脑血管系统的治疗作用而备受重视。本文以银杏外种皮为原料，用乙醇回流提取法提取其中的多酚类化合物，通过以没食子酸为标准样品的可见分光光度法测定多酚的含量，研究了乙醇浓度、浸提温度、浸提温度、料液比对多酚提取率的影响，单因素实验结合正交试验和实际操作要求确定最佳提取工艺条件，并考察了银杏外种皮中多酚清除DPPH·的能力及清除羟基自由基的能力。结果表明从银杏外种皮中提取多酚的最佳工艺条件为：乙醇浓度80%、浸提时间3h、提取温度70℃、料液比1:35，此时银杏外种皮中多酚提取量为5.02mg/g。在此条件下提取的银杏外种皮多酚对于DPPH·及羟基自由基有较好的清除能力清除率分别为60.2%和70.8%.

关键词 银杏外种皮；多酚类化合物；回流提取；抗氧化性

Abstract：Polyphenol compounds is one of the most important effective components from exopleura of ginkgo bbiloba l. on one of its compounds have antioxidant, strengthen blood vessels, promote gastrointestinal digestion, lowering blood fat, increase body resistance, prevent arteriosclerosis and thrombus formation; And diuresis, fall blood pressure, help digestion, inhibit the growth of bacteria and cancer cells, such as efficacy, especially in the treatment of cardiovascular and cerebrovascular system function and the importance. In this paper as a raw material, from exopleura of ginkgo bbilobal. which were extracted with ethanol refluxing extraction of polyphenol compounds, through with gallic acid as standard samples of spectrophotometry for determining the content of polyphenols, ethanol concentration, extraction temperature, extraction temperature and solid-liquid ratio on polyphenol extraction yield, the influence of single factor experiment combined with orthogonal test and the actual operation requirements to determine the best extraction technology conditions, and examines the testa of ginkgo biloba polyphenols clearing DPPH • ability and the ability to remove hydroxyl radicals.The experiment results showed that the optimal processing parameters were 80% , 3h, 70℃, solid-liquid ratio1:35 respectively. Polyphenols extraction quantity is 5.02 mg/g. Under the condition of the extraction of polyphenols on DPPH and hydroxyl free radical clearance rate was 60.2% and 70.8%.

Keywords Ginkgo biloba exocarp  Polyphenol compounds  Reflux extraction  Inoxidizability