Toxigenic Bacillus cereus var. fluorescens in human milk
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Updated: Oct 31, 2026
12:23
Recombinant Protein Expression, Crystallization, and Biophysical Studies of a Bacillus-conserved Nucleotide Pyrophosphorylase, BcMazG
Published on: May 16, 2017
Journal of Dairy Science
|March 1, 1984
Abstract:
Human milk with high bacterial load of B. cereus var. fluorescens is reported. The organism was identified by morphological, cultural, and biochemical characteristics. Lecithinase and haemolysin were produced in rabbit and bovine blood. The toxigenic nature of the organism was confirmed by production of necrosis on rabbit skin and fluid accumulation in rabbit ileal loop. An antibiotic resistogram also has been included.
Insights
High bacterial load of Bacillus cereus var. fluorescens was found in human milk. This toxigenic bacterium produces lecithinase and haemolysin, confirmed through rabbit skin necrosis and ileal loop fluid accumulation.
Area of Science:
- Microbiology
- Food Safety
- Bacterial Pathogenesis
Background:
- Human milk is a critical source of nutrition for infants.
- The presence of bacteria in human milk can pose health risks.
- Bacillus cereus is a known foodborne pathogen.
Observation:
- A high bacterial load of Bacillus cereus var. fluorescens was identified in human milk samples.
- The identified organism exhibited characteristic morphological, cultural, and biochemical properties.
- Lecithinase and haemolysin production was observed in both rabbit and bovine blood.
Findings:
- The toxigenic potential of Bacillus cereus var. fluorescens was confirmed via experimental models.
- Necrosis on rabbit skin demonstrated the organism's ability to cause tissue damage.
- Fluid accumulation in rabbit ileal loops indicated enterotoxin production.
Implications:
- This study highlights the potential risk of Bacillus cereus var. fluorescens in human milk.
- Understanding the pathogenicity of this bacterium is crucial for infant health and safety.
- Further research into controlling bacterial contamination in human milk is warranted.
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