Fig. 2

Purification and dextran conjugation of CDA from A. niger. The enzyme was extracted from the mycelia of A. niger, and purified by gel-filtration and ion-exchange chromatography. The molecular homogeneity of the purified enzyme was assessed. A, SDS-PAGE profile of purified CDA (M, protein ladder, Blue Plus Protein Maker, Cat # DM101, 14–100 kDa, lane 1 is the crude protein, lane 2 is the purified enzyme). B, Native-PAGE of the purified CDA from A. niger. C, Scheme of dextran activation and covalent conjugation of CDA, dextran was activated by sodium periodate forming reactive aldehyde groups to form Schiff base with the CDA surface reactive amino groups, with subsequent reduction by sodium borohydride. Specific activity (D), immobilization yield (E), and modification of surface reactive ε-amino groups of lysine residues and reactive amino groups of amide amino acids (F). The significant *p-values < 0.032, and highly significant **p-values < 0.002, were calculated by Student’s t-test to the free CDA in response to Dextran conjugation