【摘要】 旨在分离鉴定产玫瑰红色素菌株,及其分离菌株和色素对病原菌的生物拮抗作用。经形态观察、生理生化试验和16S r RNA序列分析对其进行鉴定,通过控制变量法确定最佳产色素的温度及光照条件,破裂菌体提取色素分析此菌株产色素的量和红色素的性质,采用滤纸片法研究对病原菌的拮抗作用。结果表明:(1)分离细菌Dse-01菌株最终鉴定为粘质沙雷氏菌(Serratia marcescens);(2)该菌在25~35℃条件下培养色素形成较早且颜色较深,30℃温度下产色素最佳,光照对其色素形成时间没有明显影响;(3)30℃150 r·min-1培养24 h,提取获得色素粗品确定为灵菌红素,产量达(567.90±7.77)mg·L-1;(4)分离菌株的全菌液、上清液、菌体和提取色素对病原性大肠杆菌、沙门氏菌均无拮抗作用,而全菌液、菌体和提取色素对金黄色葡萄球菌具有明显的抑制作用。更多还原

【Abstract】 This experiment was conducted to isolate and identify a microbial strain producing rosy pigment,and to study its antibacterial activity. The microbial strains were identified by morphological characteristics,physiochemical properties and 16 S r RNA gene sequence analysis. The optimization of temperature and illumination condition for rosy pigment production was investigated by variable-controlling approach. Ultrasonic fragmentation was used to extract pigment and analyze its yield and absorption spectrum. In eventually,antagonism assay to pathogens also be carried out by filter-paper method. The results showed that:( 1) a screened strain Dse-01 was identified as Serratia marcescens;( 2) The strain showed significant impact on chromogenesis under the condition of 25- 35 ℃,especially at30 ℃,which was not affected by illumination;( 3) The strain was cultured at 30 ℃ for 24 h with a shaking speed of150 r·min- 1and the extracts was prodigiosin,whose production could reach( 567. 90 ± 7. 77) mg·L- 1;( 4) the pathogenic Escherichia coli and Salmonella spp. were resistant to four active substance: Serratia marcescens,sediment of Serratia marcescens,supernatant of Serratia marcescens and pigment extraction from Serratia marcescens,whereas,Staphylococcus aureus was sensitive to all of these active products except the supernatant.更多还原