SPECIFIC ACTIVITY DETERMINATION OF ACETOLACTATE SYNTHASE FROM MAIZE(ZEA MAYS L.)

摘要

A normal spectrophotometric method has been established for determination specific activity of acetolactate synthase extracted from maize (Zea mays L.). In this study, the condition of enzyme reaction and decarboxylation of acetolactate and condition of color development of reaction complex have been determinded. The red color complex of acetion reacted wth α-naphthol and creatine was stable at room temperature within 90 min. The method has been used as determination of activity for ALS in vitro and in vivo screening model of high efficacy herbicides. Chlorsulfuron had high in vitro ALS activity to maize CAU 108, which I_(50) was 3.33 +- 0.82 nmol-L~(-1), while 2-chlorobenzenesulfonamide had almost no inhibition to ALS from maize CAU 108 in vitro. The same results were observed in in vivo A1S study of chlorsulfuron and 2-chlorobenzenesulfonamide indicated.