Abstract:

In this study, the biological characteristics of bacteriocin produced by Enterococcus faecium LPL420P06 isolated from fresh feces of pigs that can inhibit streptococcus suis were investigated. The experimental results revealed that the bacteriocin has good thermal stability and it can remain 90% of activity when heated at 90 ℃ for 30 min. It is sensitive to proteolytic enzymes such as trypsin , proteinase K, papain and neutral proteinase,  indicating that the bacteriocin is a kind of protein. It is still active after incubation in pH 5 to 9 environment for 4 h at 37 ℃. The tests on antimicrobial spectrum suggested that it not only exhibits obvious inhibition against gram-positive, such as Listeria bacteria, Staphylococcus aureus and Streptococcus suis etc, but also can inhibit several gram-negative bacteria such as Salmonella and Escherichia coli. all these show that it has a good prospect of development and ultilization.

Key words: Streptococcus suis, bacteriocin, biological characteristics