Characterization of crude invertase extracted from Aspergillus species CSA 35

The enzyme invertase is very useful, especially in food industries. Invertase hydrolyzes the disaccharide sucrose into two monosaccharides, glucose and fructose. Invertase was extracted from Aspergillus sp. CSA35, and studied using spectrophotometric methods for enzyme kinetics and determination of other factors affecting enzyme activities such as salt tolerance, pH, temperature and substrate specificity. The invertase secreted by Aspergillus sp. CSA35 has a substrate concentration (km) value of 1.25 mg/ml and maximum velocity (Vmax) of 15.15 U/mg protein. It is tolerant to salt concentrations of 3 M NaCl for 24 h and shows a broad range of substrate specificity. The enzyme activity was optimal at pH 6.0 and at a temperature of 50°C. The Vmax of the enzyme was high compared to other invertases from fungal sources, previously reported in literature. This invertase could be useful in commercial processes where high activity invertase with salt-tolerant and broad specific properties are required.   Key words: Aspergillus sp CSA35, invertase, Manihot esculenta.