Two antimicrobial substances produced by Bacillus subtilis strain B 11 were purified by boiling, DEAE 52 anion exchange chromatography and aluminum oxide adsorption chromatography, These purified substances showed onl...Two antimicrobial substances produced by Bacillus subtilis strain B 11 were purified by boiling, DEAE 52 anion exchange chromatography and aluminum oxide adsorption chromatography, These purified substances showed only one spot on silica gel thin layer chromatography （TLC）. Antimicrobial assays showed that antimicrobial substances A and B inhibited the growth of plant pathogens such as Fusarium oxysporum Schl f.sp. niveum, Rhizoctonia solani, Ralstonia solanacearum and Xanthomonas oryzae pv. oryzae. In addition, antimicrobial substance B could also inhibit the growth of Magnaporthe grisea. These two antimicrobial substances were resistant to proteolytic enzymes and temperature as high as 121℃.展开更多
In the present research, the strain SLYY-3 was isolated from sediments of Jiaozhou Bay, Qingdao, China. The strain SLYY- 3, which produced a bacteriocin-like substance （BLS）, was characterized to be a strain of Baci...In the present research, the strain SLYY-3 was isolated from sediments of Jiaozhou Bay, Qingdao, China. The strain SLYY- 3, which produced a bacteriocin-like substance （BLS）, was characterized to be a strain of Bacillus subtillis by biochemical profiling and 16S rDNA sequence analysis. It is the first time to report that Bacillus subtilis from Jiaozhou Bay sediments could produce a BLS. The BLS of B. subtillis SLYY-3 exhibited strong inhibitory activity against gram-positive bacteria （including Staphylococcus aureus and B. subtillis） and some fimgi （including Penicillium glaucum, Aspergillus niger and Aspergillus flavus）. The antimicrobial activity was detected from culture in the exponential growth phase and reached its maximum when culture entered into stationary growth phase. It was thermo-tolerant even when being kept at 100~C for 60 min without losing any activity and stable over a wide pH range from 1.0 to 12.0 while being inactivated by proteolytic enzyme and trypsin, indicating the proteinaceous nature of the BLS. The BLS was purified by precipitation with hydrochloric acid （HC1） and gel filteration （Sephadex G-100）. SDS-PAGE analysis of the extracellular peptides of SLYY-3 revealed a bacteriocin-like protein with a molecular mass of 66 kDa. Altogether, these characteristics indicate the potential of the BLS for food industry as a protection against pathogenic and spoilage microorganisms.展开更多
基金the National Natural Science Foundation of China （30260003）.
文摘Two antimicrobial substances produced by Bacillus subtilis strain B 11 were purified by boiling, DEAE 52 anion exchange chromatography and aluminum oxide adsorption chromatography, These purified substances showed only one spot on silica gel thin layer chromatography （TLC）. Antimicrobial assays showed that antimicrobial substances A and B inhibited the growth of plant pathogens such as Fusarium oxysporum Schl f.sp. niveum, Rhizoctonia solani, Ralstonia solanacearum and Xanthomonas oryzae pv. oryzae. In addition, antimicrobial substance B could also inhibit the growth of Magnaporthe grisea. These two antimicrobial substances were resistant to proteolytic enzymes and temperature as high as 121℃.
基金supported by the National Science and Technology Support Program (No. 2011BAD14B04)Project of Shandong Province Higher Educational Science and Technology Program (J14LE59)+1 种基金Applied & Basic Research Foundation of Qingdao (No. 12-1-4-3(3)-jch)Science & Technology Project of AQSIQ (No. 2012IK176)
文摘In the present research, the strain SLYY-3 was isolated from sediments of Jiaozhou Bay, Qingdao, China. The strain SLYY- 3, which produced a bacteriocin-like substance （BLS）, was characterized to be a strain of Bacillus subtillis by biochemical profiling and 16S rDNA sequence analysis. It is the first time to report that Bacillus subtilis from Jiaozhou Bay sediments could produce a BLS. The BLS of B. subtillis SLYY-3 exhibited strong inhibitory activity against gram-positive bacteria （including Staphylococcus aureus and B. subtillis） and some fimgi （including Penicillium glaucum, Aspergillus niger and Aspergillus flavus）. The antimicrobial activity was detected from culture in the exponential growth phase and reached its maximum when culture entered into stationary growth phase. It was thermo-tolerant even when being kept at 100~C for 60 min without losing any activity and stable over a wide pH range from 1.0 to 12.0 while being inactivated by proteolytic enzyme and trypsin, indicating the proteinaceous nature of the BLS. The BLS was purified by precipitation with hydrochloric acid （HC1） and gel filteration （Sephadex G-100）. SDS-PAGE analysis of the extracellular peptides of SLYY-3 revealed a bacteriocin-like protein with a molecular mass of 66 kDa. Altogether, these characteristics indicate the potential of the BLS for food industry as a protection against pathogenic and spoilage microorganisms.
