Rappaport Vassiliadis Enrichment Broth (500 gram)

Oxoid Rappaport Vassiliadis Enrichment Broth is based on the formulation described by van Schothorst and Renaud and is recommended as the selective enrichment medium when isolating Salmonella species from food and environmental specimens. It can also be used to isolate Salmonella from human faeces without pre-enrichment but the inoculum must be small. The original formulation described by Rappaport et al2 was specifically developed to exploit the four characteristics of Salmonella species when compared with other Enterobacteriaceae.

1. The ability to survive at relatively high osmotic pressures.

2. To multiply at relatively low pH values.

3. To be relatively more resistant to malachite green.

4. To have relatively less demanding nutritional requirements.

Oxoid’s Rappaport-Vassiliadis (RV) Enrichment Broth is similar to that described by Vassiliadis et al except that the peptone used is soya peptone, which has been reported to enhance the growth of salmonellae.

Rappaport Broth was found to be superior to Selenite Enrichment Broth and Tetrathionate Broth for enrichment of salmonellae with the exception of Salmonella typhi. Vassiliadis et al modified Rappaport Broth by lowering the concentration of malachite green and raising the incubation temperature to 43°C. This modified Rappaport Enrichment Broth is RV or Rappaport-Vassiliadis Medium and has been found to be superior to other salmonella selective enrichment media, especially when small inocula of pre-enrichment broth are used.

In an evaluation of different enrichment media for isolation of Salmonella from seawater, Rappaport-Vassiliadis (RV) Broth and the same broth supplemented with novobiocin were the best for detection and enumeration of salmonellae in samples with low and moderate pollution levels.

In another study10, Rappaport-Vassiliadis (RV) Broth was found to be superior to tetrathionate-brilliant green broth for the detection of salmonellae in artificially contaminated fluid whole milk.