粘质沙雷氏菌的分离鉴定及产红色素培养基的优化

Isolation and identification of Serratia marcescens and culture medium optimization for red pigment production

为确定KMR-3菌株的分类地位,对其进行了分类鉴定;为了提高其红色素产量,对发酵培养基进行了优化。以分离到的KMR-3菌株为供试材料,通过形态学、生理生化特征和16S rRNA基因序列分析对其进行了生物学分类鉴定。以LB液体培养基作为基础培养基,通过优化其不同组分(蛋白胨,酵母膏和NaCl)及含量以提高红色素产量。结果表明:KMR-3菌株归属为粘质沙雷氏菌,该菌株产红色素的最佳培养基为5g/L胰蛋白胨和1%甘油,pH5.0,温度28℃;该条件下,色素产量是基础培养基的13.4倍。该培养基蛋白用量少,促进粘质沙雷氏菌产生大量红色素,为其大规模生产提供依据。

To determine the taxonomic status of the KMR-3 strain,classification and identification were carried out. To improve the production of red pigment,the fermentation medium was optimized. With KMR-3 as the tested strain, morphology, physiological and biochemical characteristics and 16S rRNA gene sequence analysis were studied. To increase the production of red pigment,the different components（peptone,yeast extract and NaCI） and the content were optimized with LB liquid medium as a basic medium. It showed that KMR-3 strain was identified as Serratia marcescens. The optimal medium for strain producing red pigment was 5g/L tryptone, and 1% glycerol, pH5.0,temperature 28℃. Under this condition,the pigment yield was 13.4 times than those of basic medium. The culture medium not only had the characteristics of little protein using amount, but also promoted the Serratia marcescens to quickly produce a large amount of red pigment,and provided the basis for large-scale production.