Effect of pH and the bacteriocin carnocin 54 on growth and cell morphology of two Leuconostoc strains |
| |
Authors: | B. Becker W.H. Holzapfel A. von Holy |
| |
Affiliation: | Institute of Hygiene and Toxicology, Federal Research Centre for Nutrition, Karlsruhe, Germany;Department of Microbiology, University of the Witwatersrand, Johannesburg, South Africa |
| |
Abstract: | Leuconostoc carnosum LA54A produces carnocin 54, a bacteriocin inhibitory to Listeria and closely related lactic acid bacteria. The effects of the pH of cell-free LA54 culture supernatants on the antibacterial activity of carnocin 54 was assessed using Leuc. mesenteroides DSM 20343 and TA10C as indicator strains. Carnocin 54 showed greatest activity against both strains at pH 4.5. At pH 6.5, activity was reduced, especially against Leuc. mesenteroides TA10C. Scanning electron microscopy showed irregular and rough surfaces on bacteriocin-treated cells at both pH values. |
| |
Keywords: | |
|
|