Lactococcus lactis subsp. lactis HM58이 생산하는 항균물질의 특성

Characterization of antimicrobial substance produced by lactococcus lactis subsp. lactis HM58

Lactococcus lactis subsp. lactis HM58 isolated from gastrointestinal(GI) track of flounder showed the strongest inhibitory activity against Streptococcus sp. The antimicrobial substance(AMS) produced from Lactococcus lactis subsp. lactis HM58 was inactivated by pepsin or protease K treatment. However, it showed heat stability at 100℃ for 1min. Also, its antimicrobial activity was maintained between pH 2.0 and pH 10.0. The AMS production started at the exponential phase and reached its maximum at the late exponential phase. The optimal culture temperature for the production of AMS and cell growth was obtained at 30℃. The antimicrobial substance produced from Lactococcus lactis subsp. lactis HM58 inhibited cell growth of some gram positive bateria such as Bacillus subtilis, Enterococcus faecium, Enterococcus faeculis, Streptococcus agalactiae and Streptococcus sp.