给我搜一下福彩3d开奖结果 www.nfcyu.com — 365bet網址多少 —
- 文章來源：给我搜一下福彩3d开奖结果發布日期：2019-05-08 18:54 瀏覽次數：
The main production methods of amino acids are fermentation, enzymatic method, protein hydrolysis extraction method and chemical synthesis method. At present, fermentation method is mostly used. However, because of the special structure of hydroxyproline, fermentation method can not be produced, and the cost of chemical synthesis method is too high, so isolation and extraction from collagen is an important way. Protein is hydrolyzed by acid, alkali or proteolytic enzymes, and then various amino acids are separated and purified, which is called hydrolysis method for short. There are three main hydrolysis methods: acid hydrolysis, alkali hydrolysis and enzymatic hydrolysis. Alkali method can cause racemization of amino acids. The disadvantage of enzymatic method is incomplete hydrolysis. Intermediate products such as peptides are abundant, the general time is long, and the bacteria are easily polluted. They are seldom used in the production of amino acids. Therefore, acid hydrolysis is generally used to prepare hydroxyproline.