Alterations in the activity and structure of pectin methylesterase treated by high pressure carbon dioxide.
The influence of high pressure carbon dioxide (HPCD) on the activity and structure of pectin methylesterase (PME) from orange was investigated. The pressures were 8-30 MPa, temperature 55 degrees C and time 10 min. HPCD caused significant inactivation on PME, the lowest residual activity was about 9.3% at 30 MPa. The SDS-PAGE electrophoretic behavior of HPCD-treated PME was not altered, while changes in the secondary and tertiary structures were found. The beta-structure fraction in the secondary structure decreased and the fluorescence intensity increased as HPCD pressures were elevated. After 7-day storage at 4 degrees C, no alteration of its activity and no reversion of its beta-structure fraction were observed, while its fluorescence intensity further decreased.
Zhou
Linyan
L
College of Food Science and Nutritional Engineering, China Agricultural University, Key Laboratory of Fruit & Vegetable Processing, Ministry of Agriculture, Engineering Research Center for Fruit & Vegetable Processing, Ministry of Education, Beijing 100083, China.
Wu
Jihong
J
Hu
Xiaosong
X
Zhi
Xian
X
Liao
Xiaojun
X
D002245:Carbon Dioxide / Q000494:pharmacology*; D002265:Carboxylic Ester Hydrolases / Q000037:antagonists & inhibitors / Q000737:chemistry*; D032084:Citrus sinensis / Q000201:enzymology*; D004795:Enzyme Stability; D010940:Plant Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry*; D011312:Pressure
D010940:Plant Proteins; D002245:Carbon Dioxide; D002265:Carboxylic Ester Hydrolases; C022323:pectinesterase