Lactobacillus plantarum

Lactobacillus plantarum is a Gram-positive, facultatively anaerobic, rod-shaped lactic-acid bacterium. It naturally inhabits fermented foods, the human gastrointestinal tract, and various plant surfaces. In dietary supplements, it functions as a probiotic to modulate gut microbiota, improve barrier function, and support systemic health.

• Bacterial Composition: Lactobacillus plantarum is a living bacterium; its “chemical structure” is defined by its genome (≈3.3 Mbp, ~3,200 genes) and cell-wall components.
• Peptidoglycan: The peptidoglycan backbone comprises N-acetyl-glucosamine–N-acetyl-muramic acid polymers cross-linked by L-lysine-type peptide bridges (L-Ala-L-Ala).
• Lipoteichoic Acids: Lipoteichoic acids (glycerol-phosphate polymers with glycolipid anchors) and surface-exposed proteins (Msp, adhesion factors) define its interaction surface.
• Lactic Acid Production: The organism produces lactic acid (C₃H₆O₃) as its primary metabolite; the molecular formula of lactic acid is C₃H₆O₃ (IUPAC: 2-hydroxypropanoic acid).
• Extracellular Polysaccharides (EPS): Extracellular polysaccharides (EPS) consist of glucose, galactose, and rhamnose units linked via β-1,4/β-1,3 glycosidic bonds, contributing to its viscosity and immune-modulatory properties.

• Source: Commercial L. plantarum is harvested from traditional fermented foods (e.g., kimchi, sauerkraut, sourdough) or isolated from human fecal samples under strict anaerobic conditions.
• Strain Selection: Strains are selected for stability, acid and bile tolerance, and documented health effects.
• Production: Production involves a two-stage fermentation: (i) seed-culture in MRS broth, followed by (ii) large-scale fermentation in bioreactors (pH 6.2, 37 °C, anaerobic).
• Processing: Harvested cells are concentrated, washed, and lyophilised with cryoprotectants (e.g., trehalose) to preserve viability.
• Quality Control: Good Manufacturing Practice (GMP) facilities ensure ≥90 % viability at the end of shelf-life. Quality control includes strain verification by 16S rRNA sequencing, CFU enumeration, and absence of pathogens (e.g., E. coli, Salmonella).
• Quality Markers: Certified organic or non-GMO certification, as well as third-party testing for potency and contaminants, are key quality markers for consumers.