Screening Of A Thermostable α-Amylase-producing Strain And Study On It's Enzymology Properties

A thermostable α-amylase-producing strain was screened from high-temperature distilled yeast, which was identified as Streptomycete form studying its cell shape, culture, physiological, biochemical and ecological characteristics, and named Streptomyces sp. 1109.The colony of strain is small, there are goffer in the center. Aerial mycelium are white, substrate mycelium are yellowish and flourishing. The mycelium are straight, spore are smooth, and columned or bacilliform. The cell of strain are Gram-positive. Streptomyces sp. 1109 can grow in the temperature between 20 to 50℃, and the optimum temperature range is 40 to 45℃. It has no antagonistic action to Escherichia coli, Bacillus subtilis, Staphalococcus aureus and Pseudomomas aeruginosa. It can not produce pigment in various culture medium. The strain can hydrolyze starch, liquefy glutin, deoxidize nitrate, but can't produce H₂S. In adition, it can make use of arabinose, xylose, fructose, glucose, sucrose, raffinose, mannitol, inositol, sorbitol, galactose,...