Identification and characterization of two bacteriocin-producing strains of Lactococcus lactis isolated from vegetables

• Published in: International journal of food microbiology Vol. 16; no. 2; p. 141
• Main Authors: Uhlman, L, Schillinger, U, Rupnow, J R, Holzapfel, W H
• Format: Journal Article
• Language: English
• Published: Netherlands 01-06-1992
• Subjects: Anti-Bacterial Agents - pharmacology; Bacteriocins - biosynthesis; DNA, Bacterial - analysis; Food Microbiology; Hydrogen-Ion Concentration; Lactococcus lactis - drug effects; Lactococcus lactis - isolation & purification; Lactococcus lactis - metabolism; Nucleic Acid Hybridization; Temperature; Vegetables - microbiology
• ISSN: 0168-1605
• DOI: 10.1016/0168-1605(92)90007-P

Isolated from mixed salad and fermented carrots, 123 strains of lactic acid bacteria were screened for bacteriocin production. Two strains, D53 and 23, identified as Lactococcus lactis by DNA-DNA hybridizations, produced heat stable bacteriocins which were resistant to trypsin and pepsin, but were inactivated by alpha-chymotrypsin and proteinase K. The bacteriocins were active from pH 2 to 9 and inhibited species of Listeria, Lactobacillus, Lactococcus, Pediococcus, Leuconostoc, Carnobacterium, Bacillus and Staphylococcus. Strain D53 produced bacteriocin at pH values of 4.5-8.0 and from 10 to 37 degrees C.