(a)
(b)
(c)
Figure 6: Optimum pH (a) and pH stability (b) and optimum temperature (c) and thermal stability (d) of crude and purified C. viswanathii lipase. Assay conditions: 0.05 M glycine-HCl buffer pH from 2.0 to 3.0, McIlvaine buffer pH from 3.0 to 8.0, and 0.05 M glycine-NaOH pH from 8.6 to 10 at 37°C (a); the crude enzyme was incubated in the same buffers for 24 h at 10°C and lipase activity was assayed in McIlvaine buffer pH 5.0 for crude enzyme and 5.5 for purified enzyme at 37°C (b); lipase activity assays were assayed in McIlvaine buffer pH 5.0 for crude enzyme and 5.5 for purified enzyme (c); ■: crude enzyme; ●: purified enzyme.