Evaluation of lacticin 3147 and a teat seal containing this bacteriocin for inhibition of mastitis pathogens

Abstract

Lacticin 3147 is a broad-spectrum bacteriocin produced by Lactococcus lactis subsp. lactis DPC3147 which is bactericidal against a range of mastitis-causing streptococci and staphylococci. In this study, both lacticin 3147 and the lantibiotic nisin were separately incorporated into an intramammary teat seal product. The seal containing lacticin 3147 exhibited excellent antimicrobial activity and might form the basis of an improved treatment for the prevention of mastitis in dry cows.

FIG. 1

Bactericidal effect of lacticin 3147 on Streptococcus dysgalactiae M (a) and S. aureus 10 (b). Lacticin 3147 was added to Streptococcus dysgalactiae M cultures at a final concentration of 10,240 AU/ml and to S. aureus 10 cultures at a final concentration of 1,280 AU/ml. ⧫, bacteriocin added; ▪, no bacteriocin added (controls).

FIG. 2

(a) Tween 80 dependency. Tween 80 is needed for release of lacticin 3147 from the oil-based teat seal (A); there is no antimicrobial activity associated with teat seal alone (B), from seals containing Tween 80 alone (C), or from seals containing lacticin 3147 alone (D). (b) Comparison of antimicrobial activities of lacticin 3147 (A) and nisin (B) when incorporated into teat seals under identical conditions. (c) Residual lacticin 3147 activity in recovered teat seal. The control, containing no lacticin, gives no zone of inhibition.