一株拮抗O157：H7放线菌的筛选鉴定及发酵培养基

为了筛选到拮抗O157：H7的放线菌并做形态和生理生化鉴定，先采用管碟法检测抑菌能力，筛选到2株明显拮抗O157：H7的放线菌AM-8和AM-10，并鉴定为放线菌目链霉菌科链霉菌属菌种。再用单因素试验筛选到抗菌物质产量最高的碳源玉米粉和氮源蛋白胨。响应面法优化AM-8 的发酵培养基，最终确定发酵培养基为：玉米粉20.10 g/L，蛋白胨2.00 g/L，K2HPO4 0.50 g/L，MgSO4· 7H2O 0.50 g/L，NaCl 5.92 g/L，FeSO4·7H2O 0.01 g/L，CaCO3 1.89 g/L。
The purpose of this paper is to screen actinomycetes to inhabit the growth of O157：H7，and identify them by Morphological and physiological identification ，then optimize the fermentation medium of producing antibacterial substance. The antibacterial ability of the actinomycetes were detected by the method of tube plate detection. We obtained two actinomycete strains AM-8 and AM-10 which restrained O157：H7，and the genus were identified as Streptomyces. In the single factor test，the highest yield of antibacterial substances occured in the medium with corn flour as carbon source，and pep-tone as nitrogen source. After optimization of fermentation medium by response surface method，The optimum fermentation medium of AM-8 was：corn flour 20.10 g/L，peptone 2.00 g/L，K2HPO4 0.50 g/L，MgSO4·7H2O 0.50 g/L，NaCl 5.92 g/L，F2SO4 0.01 g/L，CaCO3 1.89 g/L