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A SURVEY OF AMYLOLYTIC BACTERIA AND FUNGI FROM NATIVE ENVIRONMENTAL SAMPLES

MUHAMMAD SOHAIL, AQEEL AHMAD, SALEEM SHAHZAD¹ AND SHAKEEL AHMED KHAN*

Abstract: Starches are one of the most important naturally occurring glucose polymers that are present in plants. They are used as the starting material for the production of a variety of different types of compounds of commercial importance. The usual process is the treatment of starch at an elevated temperature to gelatinize followed by liquefaction by chemicals or by enzymes. Enzymatic liquefaction has an edge over chemical treatment process. Microbes are, in general, the source of commercial enzymes. Present study was initiated to screen the microbial population for their ability to possess amylolytic potential where 117 strains of bacteria and 130 fungal strains were isolated and screened. A considerable number of both were found to produce amylase. Bacillus sp., and Aspergillus sp., were the most active amylase producers. Bacterial enzymes showed maximum activity at slightly elevated temperature and at alkaline pH while one of the fungal enzymes retained most of its activity even at a temperature of 80ºC, however, level of activity was reduced when reaction was carried out at alkaline pH. Genetic studies revealed that starch is a suitable inducer in case of fungi, while maltose seems to be a better inducer than that of starch in case of bacteria.
 

Department of Microbiology, University of Karachi, Karachi-75270, Pakistan.

Department of Botany, University of Karachi, Karachi-75270, Pakistan.