Yang Jung-Mo, Moon Gi-Seong
Department of Biotechnology, Korea National University of Transportation, Jeungpyeong 27909, Korea.
Korean J Food Sci Anim Resour. 2018 Dec;38(6):1315-1321. doi: 10.5851/kosfa.2018.e67. Epub 2018 Dec 31.
Bacteriocin is ribosomally synthesized by bacteria and inhibits closely related species. In this study we aimed at isolating lactic acid bacteria producing bacteriocin presenting anti-staphylococcal activity. A strain was isolated from kimchi for the purpose and identified by 16S rRNA gene sequencing. As preliminary tests, optimal culture conditions, stabilities against heat, solvents, and enzymes treatments, and type of action (bacteriostatic or bactericidal) of the bacteriocin were investigated. The optimal culture conditions for production of the bacteriocin were MRS broth medium and 25℃ and 30℃ culture temperatures. The bacteriocin was acidic and the activity was abolished by a protease treatment. Its stability was maintained at 100℃ for 15 min and under treatments of various organic solvents such as methanol, ethanol, acetone, acetonitrile, and chloroform. Finally, the bacteriocin showed bactericidal action against where 200 AU/mL of the bacteriocin decreased the viable cell count (CFU/mL) of by 2.5 log scale, compared with a control (no bacteriocin added) after 4-h incubation.
细菌素由细菌通过核糖体合成，可抑制密切相关的物种。在本研究中，我们旨在分离出具有抗葡萄球菌活性的产细菌素的乳酸菌。为此从泡菜中分离出一株菌株，并通过16S rRNA基因测序进行鉴定。作为初步试验，研究了细菌素的最佳培养条件、对热、溶剂和酶处理的稳定性以及作用类型（抑菌或杀菌）。产生细菌素的最佳培养条件是MRS肉汤培养基以及25℃和30℃的培养温度。该细菌素呈酸性，蛋白酶处理会使其活性丧失。其稳定性在100℃下保持15分钟，并且在甲醇、乙醇、丙酮、乙腈和氯仿等各种有机溶剂处理下也能维持。最后，该细菌素对……具有杀菌作用，在4小时培养后，与对照（未添加细菌素）相比，200 AU/mL的细菌素使……的活菌数（CFU/mL）降低了2.5个对数级。
