Table 2. Initial reaction rates of Candida rugosa lipase-catalyzed esterification of ibuprofen under various conditions.

Ibuprofen Concentration

60 mM

48 mM

36 mM

24 mM

 Isooctane

a_w = 0.73

5.02 ± 0.13

3.76 ± 0.04

3.44 ± 0.14

1.91 ± 0.08

a_w = 0.59

3.89 ± 0.07

3.25 ± 0.12

2.37 ± 0.09

1.55 ± 0.14

a_w = 0.43

1.12 ± 0.04

0.77 ± 0.02

0.33 ± 0.04

0.22 ± 0.06

 2,5-Dimethylhexane

a_w = 0.73

2.62 ± 0.28

1.46 ± 0.03

0.85 ± 0.03

ND

a_w = 0.59

1.57 ± 0.13

0.94 ± 0.02

0.58 ± 0.08

ND

a_w = 0.43

NR

NR

NR

ND

 2-Methylheptane

a_w = 0.73

3.64 ± 0.10

2.63 ± 0.20

2.02 ± 0.05

1.48 ± 0.06

a_w = 0.59

3.12 ± 0.24

2.31 ± 0.16

1.94 ± 0.06

1.20 ± 0.12

a_w = 0.43

0.71 ± 0.14

1.03 ± 0.18

1.01 ± 0.09

NR

 n-Octane

a_w = 0.73

4.00 ± 0.06

2.91 ± 0.08

2.54 ± 0.17

1.68 ± 0.08

a_w = 0.59

3.82 ± 0.07

2.45 ± 0.06

2.18 ± 0.08

1.51 ± 0.06

a_w = 0.43

0.27 ± 0.05

0.46 ± 0.04

0.28 ± 0.01

0.05 ± 0.01