تنقية و توصيف أنزيم الأنيولينيز من الفطر Aspergillus niger المعزول محليا

Inulinase from a. niger local isolate was purified. the purification steps included precipitation with ethanol 70% ,Ion exchange chromatography with DEAE-cellulose and finaly ,gel filteration (two steps) using sephadex G-150. two forms of inulinase (W and A) were obtained from the purification procedure used. inulinase forms were purified with (6.8 and 9.4) fold and (9 and 13.5) % yield , respectively. electrophoresis results confirmed the complete purity to the two enzyme forms since they gave a single band in polyacrylamide gel electrophoresis. enzyme characterization revealed that the molecular weight of the W and A forms were 72.4 and 69.18 ,respectively. the optimum pH activity was 4.5 for both enzyme forms . the W form was stable within the range (3.5-7.0) while the A form was stable within the pH (4.5- 9.0). the w form was stable with in temperature range (20-45) Cᵒ while the A form was stable within the range (20-50) Cᵒ. Km value were (1.052 and 0.909) mM and V max values were (2.86 and 5) μM / ml / min for both enzyme forms W and A , respectively.