英语语法分析

The glucoamylase from UV-48 is low thermostability but resistant to acid and alkali.

黑曲霉UV-48液化酶热稳定性高但不耐酸，糖化酶热稳定性低但耐酸和碱。

The glucoamylase was extracted and purified by PEG/(NH4)2SO4 double aqueous phase system.

利用PEG/（NH4）2SO4双水相系统从粗酶液中提取糖化酶。

In this paper, improving production level of glucoamylase was investigated by feeding medium during fermentation.

文章中研究利用补料法提高糖化酶生产发酵水平。