Bifidobacterium breve

Bifidobacterium breve is a Gram‑positive, anaerobic, non‑spore‑forming rod that naturally inhabits the human gastrointestinal tract, especially in infants and young children. As a probiotic, it is used primarily to modulate the gut microbiome, enhancing microbial balance and supporting host physiological functions through its metabolic activities and interaction with the host immune system.

Bifidobacterium breve is a living bacterial cell; its “chemical structure” is defined by its cellular components rather than a single molecular formula. Key features include:

• Taxonomy – Bifidobacterium spp.; Gram‑positive, non‑motile, anaerobic, rod‑shaped.
• Cell wall – Thick peptidoglycan layer (type A), teichoic acids, and surface‑layer proteins (SLPs) that mediate host interaction.
• Genome – ~2.1 Mbp circular chromosome, ~1 900 genes; GC content ≈ 60 %.
• Metabolic enzymes – β‑galactosidase, lactate dehydrogenase, and bile‑salt hydrolase; produce SCFAs (acetate, lactate).
• Surface molecules – Lipoteichoic acids, capsular polysaccharides (CPS), and exopolysaccharides (EPS) that influence immunogenicity.

Because the probiotic is delivered as a viable culture, quality metrics focus on CFU count, viability (percentage of live cells), and absence of contaminants (e.g., coliforms, yeasts).

B. breve strains used in supplements are isolated from human infant feces, breast‑milk, or the adult colon, where the species is naturally abundant. Commercial production follows these steps:

1. Isolation & strain selection – Isolation of a specific strain (e.g., B. breve BB‑02, B. breve UCC2003) followed by genome sequencing to confirm identity and absence of antibiotic‑resistance genes.
2. Fermentation – Large‑scale anaerobic fermentation in a controlled bioreactor (pH ≈ 6.5, 37 °C) using defined carbohydrate substrates (e.g., lactose, fructooligosaccharides) to achieve high cell density.
3. Harvest & lyophilisation – Cells are harvested, washed, and freeze‑dried with cryoprotectants (e.g., trehalose) to preserve viability.
4. Quality control – Viable count (CFU), strain purity (PCR‑based), and absence of pathogens are verified per pharmaco‑peptidic standards (e.g., USP <1210>).

For optimal efficacy, choose products that disclose the strain designation, CFU at the end of shelf‑life, and third‑party testing for microbial contaminants and potency.