中文摘要：

以红肉火龙果果皮为原料,在单因素试验基础上,根据Box-Behnken试验设计原理采用三因素三水平相应面分析法,优化火龙果果皮色素提取条件;并通过测定其色素提取液对羟自由基（·OH）、超氧阴离子自由基（O-2·）和DPPH自由基的清除能力评价其抗氧化活性。结合实际可操作性得出红肉火龙果果皮色素提取的最优工艺条件是：选用体积分数80%乙醇＋0.5%柠檬酸（体积比5∶1）为提取剂、液料比为10∶1（m L∶g）、提取温度43℃、提取时间65min。火龙果果皮色素提取液对·OH、O-2·和DPPH·的清除作用明显,清除能力与色素提取液浓度呈一定的正相关关系,但其清除能力稍低于抗坏血酸。

英文摘要：

The extraction techniques of pigment from red pitaya peel by response surface methodology method were studied on the basis of single factor test. Antioxidant activities in vitro were evaluated in three systems as follow：hydroxyl radical scavenging capacity,superoxide anion radical scavenging capacity and DPPH scavenging capacity.The results suggested that the optimal technical condition was as follows： the best extraction technology was： extracted solution 80% ethanol ＋ 0. 5% citric acid（ volume ratio 5∶ 1） in mixture,the ratio of grape peel and extraction 10∶ 1（ g∶ m L）,the extraction temperature was 43℃,and the extraction time was 65 min. The pigment extraction exhibited a concentration-dependent radical scavenging activity in three systems.