Advances in study on thermostable α-amylase;

The strain DG-4-4 was obtained through UV mutation of a thermostable α-amylase-producing strain DG-4 which was used as the starting strain.

Eexpression of the thermostable α-amylase in plants can reduce greatly costs in the production of alcohol using crop plants.

Results showed that the use of heat-stable α-amylase, with quantity of 106U/g, the composition of starch pulp 40%, the effect time of 10min for heat-stable α-amylase and liquidized temperature 94℃ could make the liquidation of potato starch most completely with the DE of.

It is proved that the best condition for the liquefaction is 20% of the rice starch concentration,12 U of the heat-stable α-amylase per one gramme starch,liquefying for 11 minutes,95 ℃ of the liquefcation temperature and pH 6.

The physiological and genetic characteristics of Bacillus licheniformis 020401 were studied, and the enzymic character of the heat-stable α-amylase produced by this strain was analyzed.

Optimum enzymes and their reaction conditions were determined after enzymatic properties of two kinds of thermostable α-amylases and two kinds of fungal-α-amylases had been studied.

In order to highly express thermostable α-amylase gene, the effect of promoters on the expression of thermostable α-amylase gene of Bacillus lichenformis was studied.