RAPPAPORT VASSILIADIS SALMONELLA ENRICHMENT BROTH

Rappaport Vassiliadis Salmonella Enrichment Broth is a selective liquid medium for enrichment and isolation of Salmonella species from a variety of clinical samples, pharmaceutical products, food and environmental samples. The formulation follows the revision by Van Schothorst et al., building on the original Rappaport Vassiliadis Enrichment Broth described by Van Schothorst and Renauld, with the addition of magnesium chloride as reported by Peterz et al. This modification increases the selectivity and allows direct enrichment from samples with low bacterial inoculum, including isolation of Salmonella from human faeces without pre-enrichment.
The medium’s selectivity is based on the natural physiological tolerances of Salmonella. Magnesium chloride increases the osmotic pressure, sodium chloride maintains osmotic equilibrium and a low pH environment buffered with phosphate promotes the growth of Salmonella and inhibits competing organisms. Malachite green also inhibits many gram positive bacteria, adding another layer of selective pressure. Soya peptone provides needed nutrients , including natural sugars, that encourage Salmonella growth and the medium’s relatively low nutrient level discourages growth of non-target flora.
Studies have shown this broth to outperform Tetrathionate Broth, Selenite Broth, and Tetrathionate Brilliant Green Broth in detecting Salmonella in milk. Enriched cultures can be subcultured onto Xylose Lysine Deoxycholate (XLD) Agar for further isolation and confirmation.

Rappaport Vassiliadis Salmonella Enrichment Broth is used for selective enrichment of Salmonella species from clinical samples