Abstract
The oxidation of linoleic acid catalyzed by soybean lipoxygenase (LG) I (optimum pH9.0) in a hexane-water biphasic system was studied in response to chemical modification and the use of additives. The amino groups on LG I were acylated by N-acyloxysuccinimides (1) in a phoshate buffer. The modified LG I showed enzyme activity in the biphasic system. In the unmodified form, this activity was slight due to its lack of stability. Efficiency of the modifier for bringing about activity increased with CN (carbon nunber of acyl group) in (1). On the other hand, stability decreased with increasing CN in the modifier. The addition of BSA modified by (1) (CN=6 and 8) also elicited activity in the biphasic system, while additives such as BSA, casein and NaCl had no significant effect.
Based on these observations, a mechanism for the occurrence of LG activity in the biphasic system is proposed and discussed.
