甘油包埋绿豆SOD的稳定性研究

The Studies on Stability of Glycerin Entrapment SOD from Mungbean( Phaseolus radiatus L.) Seeds

摘要:

用不同浓度的甘油包埋绿豆(Phaseolus radiatus L.)超氧化物岐化酶(Superoxide dismutase, SOD)，对不同条件下制备的甘油SOD的稳定性进行评估。结果表明：甘油包埋绿豆SOD的稳定性受甘油浓度影响明显，12.5%~25%为最适甘油浓度。在10℃、pH 6.8、搅拌速度1 000 r min-1条件下包埋的甘油SOD在55℃的平均半衰期为25.1 d, 为非包埋SOD的5.1倍。甘油浓度为25%，温度分别为5℃、10℃、25℃、45℃条件下，pH 3.8中包埋的绿豆SOD耐酸性较好，pH 8.9下包埋的绿豆SOD的抗碱能力较强。在包埋过程中添加一定浓度的Zn2+、Cu2+、Fe2+有利于其热稳定性的提高。甘油包埋SOD对一些常见的化妆品添加剂也有一定的抗性。由此可见，甘油包埋技术可望作为一项有应用前景的SOD活性保持新技术，有利于极端温度和极端pH条件下的SOD的应用。

Abstract:

Superoxide dismutase (SOD) extracted from mungbean (Phaseolus radiatus L.) seeds was entrapped with glycerin of various concentrations under various treatment conditions, then their stabilities were estimated. The results showed that the stability of SOD under hot stress, as well as, extreme acidic or alkaline stress was enhanced by glycerin entrapment. The concentration of glycerin was regarded as an essential factor for SOD stability, the optimum glycerin concentration was 12.5%～25%. It was demonstrated that 10℃, pH 6.8 and 1 000 r min-1 of mix round was the optimum condition to improve the SOD stability under hot stress, the half life of glycerin entrapment SOD in hot stress at 50 ℃ was 25.1 d, which was 5 times of the natural SOD not glycerin entrapment. Entrapment at pH 3.8 was more effective to improve the endurance of SOD in acidic stress，whereas, pH 8.9 was more resultful to enhance the stability in alkaline stress. Adding of Zn2+、Cu2+、Fe2+ was favor to enhance the stability of glycerin entrapment SOD under hot stress. Glycerin entrapment SOD also showed a rather strong tolerance in some additives of cosmetics. So glycerin entrapment would be a promising way to improve SOD stability in various stress conditions, which might enhance its various applications effectively in the near future.