The enantiomeric ratio ( E ) is frequently used to characterize the enantioselectivity in enzyme-catalyzed kinetic resolution. In this paper two methods are evaluated in terms of accuracy

sensitivity towards E and its distribution.For the equation of Chen et al

the probability of r(eep)∈[0.5

1.0]

the influence on E of enanatiomeric excess of product ( eep)

nearly reaches 0.75.The probability of r(eep)∈[0.7

1.0] exceeds one half.All r(eep) values are higher than 0.6 at conversion ratio ( C ) below 50%. For the equation of Rakels et al

the majority of r(eep) exceeds 0.6 when ee s

enantiomeric excess of substrate is lower and eep is higher.During the final phase of a reaction when ees is large

the changes of ees have greater effects on E than that of eep

but the probabilities for the above two cases do not exceed 0.5.In addition

there are quite a few situations in which r(eep) is equal to 0.4

0.5 and 0.6. This is the most distinguished discrimination of two methods and may also be the primary reason for which the latter is superior to the former.