ENZYME-ACTIVITIES IN PREHARVEST RICE GRAINS

被引：4
作者：
CHRASTIL, J
机构：
[1] Southern Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, New Orleans
来源：
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY | 1993年 / 41卷 / 12期
关键词：
D O I：
10.1021/jf00036a004
中图分类号：
S [农业科学];
学科分类号：
09 ;
摘要：
The enzyme kinetic parameters (equilibria, specific rate constants, initial velocities, and diffusion resistance constants) of several different enzymes alpha-amylase, phospholipase c, acid phosphatase alkaline phosphatase, peroxidase, and cytochrome c reductase) have been studied in the long-grain rice variety (Lemont) during the preharvest period (14, 30, and 50 days after flowering). During this period before harvest, the enzymic substrate inhibitors increased in all studied enzyme systems. The specific rate constants (activities) of alpha-amylase, phospholipase c, alkaline phosphatase, and peroxidase increased. On the other hand, the specific rate constant of acid phosphatase decreased and that of cytochrome c reductase remained unchanged during this ripening period. The changes were faster than, but qualitatively similar to, the changes in stored rice grains after harvest. Thus, there was no qualitative discontinuity in these parameters at and after harvest.
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收藏
页码：2245 / 2248
页数：4
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