菜籽粕脱毒液中植酸的提取及其抗氧化活性

摘要

Detoxified rapeseed meal solution was extracted by alkaline precipitation method to obtain phytic acid and the antioxidant activity of phytic acid obtained was evaluated through exploring its effect on acid value and peroxide value of lard using BHT as the positive control.Meanwhile,the antioxidant activity was also investigated through comparing its scavenging capacities against hydroxyl,superoxide anion and DPPH free radicals as well as hydrogen peroxide,determined by flow injection chemiluminescence and visible spectrophotometric methods,with those of VC.The results showed that the best condition for the extraction of phytic acid was pH 8.Under the optimal extraction condition,the yield of phytic acid was 92.83% and the purity was 45.96%.The extracted phytic acid could inhibit rancidity and peroxidation in lard with a better effect than that of BHT.The extract revealed the strongest scavenging effect against superoxide anion free radicals,followed by hydroxyl free radicals,hydrogen peroxide and DPPH free radicals.Moreover,it was superior to vitamin C in scavenging superoxide anion and hydroxyl free radicals.Therefore,the extract is a good natural antioxidant.%采用碱沉淀法从菜籽粕脱毒液中回收提取植酸并对该制备植酸的抗氧化活性进行研究。以BHT为阳性对照,考察植酸对猪油的酸价和过氧化值的影响;采用流动化学发光法和可见分光光度法,以VC为阳性对照,考察植酸清除羟自由基（.OH）、超氧阴离子自由基（O2.）、1,1-二苯基-2-苦苯肼自由基（DPPH自由基）及H2O2的能力。结果表明：回收提取植酸以NaOH调节溶液pH8为优,得率达92.83%,植酸含量为45.96%;植酸对猪油的酸败和过氧化有一定的抑制作用且优于BHT;制备植酸（实验制备）清除各种自由基的能力依次为：O2.〉.OH〉H2O2〉DPPH自由基,且除DPPH自由基外对其他自由基清除效果均优于VC。表明植酸是一种较好的天然抗氧化剂。