Screen and Mutation of Strains for Acetic Acid Fermentation by Method of ARTP

[Objective] The aim was to screen acetic acid bacteria with thermal tolerance for acetic acid fermentation. [Method]The Pei of Shanxi aged vinegar was collected to screen acetic acid bacteria,and then the strain was mutated with the method of ARTP( Atmospheric and Room Temperature Plasma). [Result] A strain of acetic acid bacteria WL021 identified as Acetobacter pasteurianus,which possessed the feature of thermal tolerance,was screened from the Pei of Shanxi aged vinegar. The optimal acetic acid fermentation temperature of strain WL021 was 35℃. The strain WL021 was treated with ARTP and then A. pasteurianus WL021-1 was obtained,which exhibited higher fermentation efficiency at35 ℃. The acetic acid fermentation was performed with a 15 L fermenter under the conditions of temperature 35 ℃,air flux 0. 15 vvm,and the initial alcohol concentration 7%. As a result,an average fermentation efficiency of 1. 10 g /( L·h) was achieved,which was 10% higher compared with the original strain,and the period of fermentation was 7 h reduced,though the final concentration of acetic acid and the alcohol conversion ratio were almost the same.[Conclusion]The strain of A. pasteurianus WL021-1 with the optimal fermentation temperature 35 ℃ is obtained. The cost of temperature control can be reduced when it is used for industrial acetic acid fermentation.