Production and Properties of alpha-Amylase from Penicillium chrysogenum and its Application in Starch Hydrolysis

摘要

Fungi were screened for their ability to produce a-amylase by a plate culture method.Penicillium chrysogenum showed high enzymatic activity.a-Amylase production by P.chrysogenum cultivated in liquid media containing maltose (2%) reached its maximum at 6-8 days,at 30deg C,with a level of 155 Uml~(-1).Some general properties of the enzyme were investigated.The optimum reaction pH and temperature were 5.0 and 30-40deg C,respectively.The enzyme was stable at a pH range from 5.0-6.0 and at 30deg C for 20min and the enzyme's 92.1% activity's was retained at 40deg C for 20min without substrate.Hydrolysis products of the enzyme were maltose,unidefined oligosaccharides,and a trace amount of glucose.a-Amylase of P.chrysogenum hydrolysed starches from different sources.The best hydrolysis was determined (98.69%) in soluble starch for 15 minute at 30deg C.