【作者】 马静静； 王小芬； 高丽娟； 杨洪岩； 崔宗均；

【Author】 Jing-Jing MA Xiao-Fen WANG Li-Juan Gao Zong-Jun CUI (1 Center of Biomass Engineering;College of Agronomy and Biotechnology,China Agricultural University,Beijing,100094;2 Center of Beijing Physical and Chemical Analysis,Beijing,100089)

【机构】 中国农业大学农学与生物技术学院中国农业大学生物质工程中心； 北京市理化分析测试中心；

【摘要】 为了探明秸秆发酵用乳酸菌复合系 SFC-2对杂菌的抑制作用。从秸秆自然发酵体系中,利用平板划线法、纸片扩散法和变性梯度凝胶电泳(DGGE)筛选出13株菌作为研究该乳酸菌复合系抑菌作用的对象。通过16S rDNA 序列分析显示其中有9株菌的近缘种为 Enterobacter cloacae、Klebsiella oxytoca、Bacillus cereus、Klebsiella pneumoniae、 Citrobacter freundii、Klebsiella terrigena、Citrobacter sp,这些均为常见的致病菌或条件致病菌。将筛选出的致病菌作为被测试菌株,用 SFC-2的发酵上清液处理结果表明:SFC-2 发酵上清液抑制所有被测试菌株的生长,SFC-2复合系的抑菌作用高于复合系分离的单一菌株和单一菌株人工组合的抑制作用;在 SFC-2培养的14-48h 内,取7次发酵上清液测定结果, 抑菌活性时间差异不显著;发酵过程产生有机酸是抑制杂菌的一个重要因素;非有机酸抑菌物质对热稳定,因此认为复合系的抑菌机制是多因子作用的结果。更多还原

【Abstract】 Through continuous restricted subcultivation,a lactic acid bacteria(LAB) community SFC-2 was screened from fermented crop straw.To figure out the atibacterial activity of lactic acid bacteria (LAB) community SFC-2 in fermented crop straw.Through plate isolation, inhibitory experiment and screening of Denaturing Gradient Gel Electrophoresis (DGGE),13 isolated strains inhibited intensely by SFC-2 cell-free culture supernatant were obtained from poor quality fermented rice straw.Phylogenetic analysis of the 13 strains based on 16S rDNA gene sequence data indicated that nine strains were belong to Enterobacter cloacae,Klebsiella oxytoca,Bacillus cereus,Klebsiella pneumoniae,Citrobacter freundii,Klebsiella terrigena,Citrobacter sp,and they were all familiar pathogen or conditioned pathogen.Indicating bacteria selected from the pathogens were used to detected antibacterial activity of SFC-2 cell-free culture supernatant.The results showed that:SFC-2 community had stronger antibacterial activity than isolated strains from SFC-2 community,had stronger antibacterial activity than man-made communities against indicating bacteria;antibacterial activity of SFC-2 community was no varied in 14-48 hour cultured;the mechanism underlying the antibacterial activity of SFC-2 community appears to be multifactorial and including production of organic acid and of bacteriocins and nonbacteriocin,organic acid was important antibacterial factor for SFC-2 community,the antibacterial substances was heating steadily.更多还原