摘要：花青素(Anthocyanidin)，也称之为花色素，是一种水溶性色素属于类黄酮化合物，在天然环境中十分普遍。它不单光彩亮丽有保障的特征而且具有抗氧化以及与多种其他保健功能，因此现在已经大量投入产业化开发来满足人们的生活和工作的更高需求。本课题拟提取高纯度的紫甘薯花青素，并研究其抗氧化活性，旨在更深入地认识到其开发潜力，为产业化开发打下坚实的基础，以期使之成为天然色素市场的标杆。51851

试验通过对新鲜紫甘薯进行切条、烘干、粉碎后得到紫甘薯粉末。紫甘薯粉末粗提取花青素步骤为：使用浓度50 %的甲醇对其进行提取、放入60 ℃水浴中超声20 min、之后取出配平放入12000 r/min离心机中离心10 min后取出上清液，将上述步骤重复提取三次。

使用AB-8大孔树脂以流速1 mL/min对紫甘薯花青素粗提取液进行纯化，再用70 %乙醇水溶液对其洗脱处理，将洗脱液通过旋转蒸发至黏稠后冷冻干燥得到花青素样品。

    将提取出的花青素样品进行清除DPPH·自由基和ABTS+自由基的实验，以此来检验其抗氧化活性，用VC作为参照对象。依照实验数据观察发现，样品花青素展现出了较强的自由基清除能力，而且在浓度的不断增加的对比试验中，紫甘薯花青素的抗氧化活性也持续加强，而且紫甘薯花青素样品也不断靠近抗坏血酸（VC）自由基清除能力。

毕业论文关键词:紫甘薯花青素、提取纯化、抗氧化活性

The study on the extraction and purification and antioxidant activies of anthocyanins from purple sweet potato

Abstract:Inartificial anthocyanin is a kind of water-solubility coloring matter which is widely indwelled in plant, and it belongs to flavones compound. As a result of its vivid color and luster, anti-oxidation and other function of health care, in order to making people's works and lives better, it has been put into industrialization produce.This paper intends to high purity of Purple Sweet Potato Anthocyanin extraction, and its antioxidant activity were studied, laying the foundation for the industrialized production, in order to become natural red pigment market leading products; on the antioxidant activity of purple sweet potato anthocyanins research to more deeply understand its application value and provide experimental basis for the use of anthocyanins from purple sweet potato on further development of the health food, cosmetics and pharmaceutical industry.

The purple sweet potato powder was obtained by cutting, drying and grinding the purple sweet potato.The conditions of extracting anthocyanin from purple sweet potato powder were as follows: methanol concentration 50 %, extraction temperature 60 degrees C, ultrasonic 20min, centrifugal 10min, extracting three times.

The AB-8 macroporous resin was used to purify the crude extract of Purple Sweet Potato Anthocyanin according to the flow rate of 1mL/min.With 70% ethanol elution, the eluate was dried to obtain pure anthocyanins by rotary evaporation to sticky after freezing.

The experimentally obtained in purple sweet potato anthocyanins pure product in the removal of the contrast experiment of DPPH· and ABTS+ radicals exhibit strong free radical scavenging capacity and with the increase of the concentration of, Purple Sweet Potato Anthocyanin antioxidant activity enhanced, when the concentration reached 2 mg/mL of anthocyanins from purple sweet potato pure product of free radical scavenging ability and ascorbic acid (VC) close to.

Key word: purple sweet potato anthocyanin; extraction; antioxidant activities

目录

1.前言 5

1.1食品色素 5

1.2花青素概述 5

1.3紫甘薯花青素的研究近状 甘薯花青素提取及其抗氧化活性研究:http://www.751com.cn/shiping/lunwen_55625.html