不同保护剂对木瓜蛋白酶活力和稳定性的影响

Effect of Different Protective Agent on the Enyzme Activity and Stability of Papain

关键词:  木瓜蛋白酶  焦亚硫酸钠  L-半胱氨酸  谷胱甘肽  酶活力

Key words:  papain  sodium metabisulfite  L-cysteine  glutathione  enzyme activity

摘要:

为提升木瓜蛋白酶活力和稳定性，本研究在其生产过程中添加不同试剂，以添加试剂7 d后的蛋白酶活力为评价指标进行初筛，筛选出对木瓜蛋白酶活力具备保护作用的试剂，进而将保存时间延长至88 d开展复筛。研究结果表明，稳定性最佳的3种试剂分别为焦亚硫酸钠、L-半胱氨酸和谷胱甘肽；确定其对木瓜蛋白酶的最适保护浓度依次为0.10%、0.60%、0.40%；稳定性排序为焦亚硫酸钠＞L-半胱氨酸＞谷胱甘肽。这3种试剂均能在木瓜蛋白酶保存阶段有效保护酶活力(木瓜蛋白酶活力能在58 d内保持相对稳定)，减少酶活力损失，提升经济效益。研究结果可为木瓜蛋白酶工业生产及保存过程中稳定性的提高提供重要理论依据与实践指导。

Abstract:

In order to improve the enzyme activity and stability of papain,different reagents were added in the production process in this study.The enzyme activity after 7 d of adding reagents was used as the evaluation index for preliminary screening,and the reagents with protective effect on papain enzyme activity were screened out,and then the storage time was extended to 88 d for re-screening.The results showed that the three reagents with the best stability were sodium metabisulfite,L-cysteine and glutathione.The optimum protective concentration of papain was determined to be 0.10%,0.60% and 0.40%,respectively.The order of stability was sodium metabisulfite > L-cysteine > glutathione.These three reagents can effectively protect the enzyme activity during the preservation of papain (papain enzyme activity can remain relatively stable within 58 d),reduce the loss of enzyme activity,and improve economic benefits.The results of this study can provide important theoretical basis and practical guidance for the improvement of the stability of papain during the process of industrial production and preservation.