Method adding trehalose to strengthen production strength of 2-keto-L-Gulonic acid

Abstract

The invention discloses a method adding trehalose to strengthen production strength of 2-keto-L-Gulonic acid, belonging to the technical filed of ferment preparation of vitamin C. The invention takesthe mixing strain of Ketogulonigenium vulgare and Bacillus megaterium as a production strain, and 10mmol.L<-1> of trehalose is exogenously added into fermentation culture medium to be used as protective agent, therefore, the cell growth and production of 2-keto-L-Gulonic acid (2-KLG) are promoted, and the efficient production of 2-KLG is realized. When 10mmol.L<-1> of trehalose is added under a hyperosmotic condition (1067.5mOsmol.kg<-1>), the content of 2-KLG is 56.83g.L<-1> at 72h, which is 1.94 times of the content of 2-KLG of a matched group that adds no trehalose under the hyperosmotic condition, wherein the content of 2-KLG of the matched group is 29.24g.L<-1>. When 10mmol.L<-1> of trehalose is added under a normal fermentation condition adding no NaCl, the fermentation period is shortened to 52h, the end point acid production is up to 69.38g.L<-1>, and the consumption speed of L-sorbose and the production intensity of 2-KLG are respectively increased by 43.1% and 45.5%.

Description

technical field [0001] The invention discloses a method for adding trehalose to enhance the production strength of 2-keto-L-gulonic acid, which belongs to the technical field of vitamin C preparation by fermentation. Background technique [0002] Vitamin C (i.e. L-ascorbic acid) is an essential vitamin for the human body. It has a wide range of physiological functions. It has important uses in medicine and food industry, and occupies a very important position in the production of vitamin drugs. At present, the production of vitamin C in my country mainly adopts the "two-step fermentation method". The main feature of this process is that the second step of fermentation, that is, the conversion from L-sorbose to 2-keto-L-gulonic acid (2-KLG) needs to be produced by Ketogulonigenium vulgare (commonly known as "small bacteria") Combined with Bacillus megaterium (commonly known as "big bacteria") for mixed fermentation. [0003] Although the "two-step fermentation method" repla...

AI Technical Summary

Problems solved by technology

At present, the addition of trehalose to improve the tolerance of mixed strains to hyperton...