الفهرس 
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Abstract
A total of five Thermomyces lanuginosus isolates were isolated from compost samples from Shata fertilizer factory of Damietta and mushroom compost. The isolates were tested for their amylolytic activities by growing in yeast–soluble starch agar medium. Thermomyces lanuginosus isolates D1 and D2 were optimized for the production of α-amylase. The optimum conditions for the production can be summarized as follows: 10 days incubation, Temperature of 45oC, pH of 5.0 for strain D1 and 6.0 for strain D2. Starch and yeast extract as the best carbon and nitrogen sources. Thermomyces lanuginosus isolates D1 and D2 were able to grow and produce α-amylase on all lignocellulosic materials examined (wheat bran, rice bran, corn cob and corn steep liquor). Crude extracellular α-amylase was characterized. The optimum pH and temperature of amylase activites were 3.0 and 50oC, respectively for both isolates. The enzymes of the two isolates were stable at 50oC and 60oC over 8 hours. Purification of extracellular α-amylase of Thermomyces lanuginosus isolates D1 and D2 were carried out by ammonium sulphate precipitation in concentration of 70% and 90% for both isolates D1 and D2, respectively, dialysis, anion exchange chromatography and then a gel filtration chromatography.