关键词: 16S rDNA, 玉米肠, 枯草芽孢杆菌, 鉴定, 响应曲面, 防腐剂

Abstract:

【Objective】 A microorganism strain ym11 causing corn sausage to corrupt and become soft and sticky was isolated from the surface of corn sausage in order to construct control technology to assure safety of corn sausage. Authenticate and optimization of preservatives were studied with the ym11 stain. 【Method】 The microorganism stain was identified by using the 16S rDNA sequence analysis, and different preservatives were determined by MICs and optimization of preservatives mixture was also studied. 【Result】 The result indicated that it was Bacillus subtilis and homologous similarity was 97%. It was more sensitive to nisin, polylysine, ethylparaben, whose MICs were 39mg•L-1, 39 mg•L-1, 125 mg•L-1, respectively. Optimization result showed that ym11 in the medium could be reduced two logs when the concentrations of nisin, polylysine, and ethylparaben were 11.30 mg•L-1, 10.90 mg•L-1, and 4.80 mg•L-1, respectively. 【Conclusion】 The ym11 strain belongs to Bacillus subtilis. It can be sterilized effectively by using preservatives mixture.

Key words: 16S rDNA, corn sausage, Bacillus subtilis, identification, response surface methodology, preservative