Rappaport-Vassilidis Broth

//Rappaport-Vassilidis Broth

Rappaport-Vassilidis Broth

SKU: KM0047 Category:

Rappaport-Vassiliadis Soya Broth is used for the enrichment and selective isolation of Salmonella spp. This medium is a modification of the original formulation by Rappaport et al. and has been formulated to exploit the full characteristics of Salmonella spp. These characteristics include the ability to survive at relatively high osmotic pressure, to multiply at low pH values and greater resistance to malachite green.
This formulation also has the correct amount of magnesium chloride as previous formulations did not take into account the volume of displacement caused by dissolving large amounts of magnesium chloride in water. This formulation has been shown to be superior to tetrathionate broth and selenite broth for the isolation of Salmonella spp. from meat products.
Soya peptone provides the required carbon, nitrogen and vitamins. Potassium dihydrogen phosphate and di-potassium hydrogen phosphate act as buffers. Magnesium chloride raises the osmotic pressure in the medium. Malachite green is an inhibitory substance.
NB: This formulation is very hygroscopic and will produce a slight exothermic reaction when mixed with water.

 

Additional Information

Shelf Life (days)

Storage Temp (°C)

Dehydrated Medium Appearance

Prepared Medium Appearance

Dehydrated Medium Colour

Prepared Medium Colour

Dehydrated PH

Prepared PH

Product Description

Organisms Ref. No Result
Salmonella typhimurium NCTC 12023 Growth
Escherichia coli NCTC 12241 Inhibited

 

Formula*

g/L
Soya peptone 4.5
Sodium chloride 7.2
Potassium dihydrogen phosphate 1.26
Di-potassium hydrogen phosphate 0.18
Magnesium chloride (Anhydrous) 13.58
Malachite green 0.036
Total 26.75
*Adjusted/supplemented as required to meet performance requirements

Preparation

Suspend 26.75g of the medium in one litre of deionised / purified water. Allow the medium to dissolve whilst mixing for 10 minutes. Dispense into final containers and sterilise at 115°C for 15 minutes.