动态高压微射流技术对木瓜蛋白酶活性的影响(英文)

研究了动态高压微射流技术对木瓜蛋白酶活性的影响,并以荧光光谱为检测手段对木瓜蛋白酶的分子构象进行表征。结果显示,动态高压微射流处理(120~180 MPa)后,木瓜蛋白酶酶活降低。经180 MPa处理1次,木瓜蛋白酶相对酶活降至90.04%。随着处理压力的增加,木瓜蛋白酶分子、酪氨酸残基、色氨酸残基的荧光发射峰位置分别从对照组的334、285、277.5 nm红移至140 MPa处理组的335.5、285.5、278.5 nm,然后回移至180 MPa处理组的334、285、278 nm。在0~4℃放置24 h后,酶活进一步降低,木瓜蛋白酶和酪氨酸残基的荧光强度出现波动(降低、上升然后再降低),表明动态高压微射流处理(120~180 MPa)改变木瓜蛋白酶分子构象的效果较为明显,形成的新构象稳定性低。

The Effect of Dynamic High Pressure Microfluidization on the Activity of Papain

The effect of dynamic high pressure microfluidization (DHPM) on the activity of papain had been investigated , and the molecular conformation changes of papain had been detected by fluorescence spectra. The results showed that after DHPM (120～180 MPa) treatment, the enzyme activity decreased in different degrees. The papain activity reduced to 90. 04% after 180 MPa treatment. With the increasing of treatment pressure,the fluorescence emission peaks of papain,Tyr and Trp residues gradually red shifted from 334,285 and 277.5 nm for untreated sample to 335. 5,285. 5 and 278. 5 nm for 140 MPa treated sample, and then returned to 334,285 and 278 nm for 180 MPa treated sample,respectively. After 24 h placing at 0～4 ℃ .papain activity further decreased and the fluorescence intensity of papain and Tyr residue showed oscillate (down,up and down), which indicated that DHPM treatment (120～180 MPa) changed the molecular conformation of papain visibly with low stability of the new formed conformation.