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A Method to Assess Bacteriocin Effects on the Gut Microbiota of Mice
Published on: July 25, 2017
Bacteriocin-Producing Strain of Lactococcus lactis subsp. diacitilactis S50
M Kojic1, J Svircevic, A Banina
1Institute of Molecular Genetics and Genetic Engineering, Vojvode Stepe 283, P.O. Box 794, 11001 Belgrade, Yugoslavia.
Applied and Environmental Microbiology
|June 1, 1991
Summary
Lactococcus lactis S50 produces bacteriocin S50, effective against Lactococcus species. This bacteriocin is protease-sensitive but heat and pH stable, showing potential for food preservation.
Area of Science:
- Microbiology
- Food Science
- Bacteriocin Research
Background:
- Lactococcus lactis subsp. diacitilactis S50 is a known producer of antimicrobial compounds.
- Bacteriocins are ribosomally synthesized peptides with antimicrobial activity, often used as food biopreservatives.
- Understanding the properties of novel bacteriocins is crucial for their application.
Purpose of the Study:
- To characterize bacteriocin S50 produced by Lactococcus lactis subsp. diacitilactis S50.
- To determine the antibacterial spectrum and stability of bacteriocin S50.
Main Methods:
- Production of bacteriocin S50 by Lactococcus lactis subsp. diacitilactis S50.
- Testing antimicrobial activity against various Lactococcus species, including nisin producers.
- Assessing bacteriocin S50 stability against proteases, heat, and pH variations.
Main Results:
- Bacteriocin S50 exhibited a narrow antibacterial spectrum, active only against Lactococcus species.
- A bactericidal effect was observed against a nisin-producing strain.
- Bacteriocin S50 activity was sensitive to proteases but remained stable after heating to 100°C for 60 min and across a pH range of 2-11.
Conclusions:
- Bacteriocin S50 is a novel antimicrobial peptide with specific activity against Lactococcus species.
- Its stability under various conditions suggests potential applications in the food industry.
- Further research into bacteriocin S50 could lead to new food preservation strategies.
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