交替假单胞菌LP621菌株产右旋糖苷酶的培养条件优化

从江苏连云港海域分离和筛选到1株产右旋糖苷酶的海洋细菌交替假单胞菌Pseudoalteromonas tetraodonis LP621,通过单因素试验和正交试验对该菌株产右旋糖苷酶培养条件进行优化。单因素试验结果表明,最佳培养时间为24 h,最适产酶温度为25℃;产酶pH范围为5.0~11.0,最适产酶pH为6.0;产酶NaCl浓度范围为1%~10%,NaCl浓度为4%时产酶较高;装液量在25%。麦芽糖、胰蛋白胨和酵母膏促进产酶。利用响应面方法对LP621产右旋糖苷酶的发酵条件进行优化。选择培养基pH、时间、麦芽糖浓度和装液量4因素进行优化,结果为pH 7.07,发酵时间21.94 h,麦芽糖浓度0.42%,装液量为21.88%,酶活为270.1U/mL。

Culture Optimization of Dextranase-Producing Pseudoalteromonas tetraodonis LP621

A dextranse-producing marine bacteria Pseudoalteromonas tetraodonis LP621 was screened and isolated from the sea area of Lianyungang,Jiangsu.Its dextranase production conditions was optimized through single-factor and orthogonal experiments.The results of single factor experiment indicated that the most suitable culture condition was 24 hours,and the most suitable dextranse producing temperature was 25 ℃ at pH 6.0 with ranging 5.0~11.0,and the range of the concentration of NaCl for the dextranse production was 1%~10%,and the yield of dextranase was fairly high at 4% of NaCl with filling volume rate at 25%.Maltose,tryptone,and yeast extract enhanced the enzyme production.Response surface method was adopted to optimize the enzyme production fermentation conditions.Medium pH,time,maltose,and filling volume four factors were selected for the optimization.And the results were pH 7.07,21.94 h,maltose 0.42%,and filling volume 21.88%,the enzyme activity was 270.1 U/mL.