【摘要】 为了探讨产乳酸的葡萄球菌对青贮发酵的作用,试验以青贮3个月的豆科牧草疏叶骆驼刺为材料,采用MRS培养基分离、纯化细菌,革兰染色后进行细胞形态学观察,并进行生理生化特性鉴定和16S rDNA序列分析。结果表明:菌株呈球状,G+,无芽孢;产乳酸,液化明胶,水解淀粉,触酶阳性,温度生长范围为15~35℃,酸生长范围(p H值)为4~7,Na Cl生长范围为2%~12%,可利用多种碳源和氮源;该菌株与模式菌株ATCC 29971的相似性为99.7%。说明该菌为木糖葡萄球菌(Staphylococcus xylosus)。更多还原

【Abstract】 To explore the role of Staphylococcus producing lactic acid on silage fermentation,Alhagi sparsifolia shap ensiled for three months was taken as material. The MRS medium was used to separate and purify the bacterium. The identification of physiological and biochemical characteristics and 16 S rDNA sequence analysis were conducted after Gram staining and the cell morphological observation. The results showed that the bacterial strain was sphere- shaped,Gram- positive,and without spores. The strain showed positive reaction for producing lactic acid,gelatin liquefaction,starch hydrolysis and positive catalase. The temperature for bacterial growth ranged from 15 ℃ to 35 ℃,and the p H value for bacterial growth ranged from 4 to 7,and the Na Cl for growth bacterial ranged from 2% to 12%. The strain could utilize a variety of carbon and nitrogen sources,and shared 99. 7% similarity with the type strain ATCC 29971. The result indicates that the strain was Staphylococcus xylosus.更多还原