De Man, Rogosa and Sharpe (MRS) Broth

This medium is intended for the cultivation and enumeration (via the Miles and Misra technique) of Lactobacillus spp. from a variety of sources and can be used in conjunction with MRS Agar (KM0080).

This medium is a modification on the formulation developed by de Man, Rogosa and Sharpe.

The peptones, beef extract, yeast extract provides the required carbon, nitrogen and vitamins in this medium. Glucose is a fermentable carbohydrate. Potassium phosphate is a buffering agent. Selectivity of the medium is achieved through the use ofammonium citrate and sodium acetate, inhibiting microorganisms such as streptococci and moulds. The magnesium sulphate, manganese sulphate and polysorbate 80 act as growth stimulants.

The medium can be made more specific for lactobacilli generally by lowering the pH to between 5.0 and 5.5.This has the effect of inhibiting most streptococci that may otherwise grow on the medium and can be readily confused with lactobacilli.

For the cultivation and enumeration (via the Miles and Misra technique) of Lactobacillus spp. from a variety of sources and can be used in conjunction with MRS Agar (KM0080).

Additional InformationShelf Life (days)1095 daysDehydrated Medium AppearanceFine PowderDehydrated Medium ColourStrawDehydrated PH6.5 0.2Prepared Medium AppearanceLiquidPrepared Medium ColourDark StrawPrepared PH6.5 0.2Recommended IncubationAerobically at 30 1C for up to 3 days.Container500G, 5KG, 10KGFormula*g/LPeptones9.75Yeast extract4.0Beef extract8.0Glucose20.0Potassium phosphate2.0Sodium acetate5.0Ammonium citrate2.0Magnesium sulphate0.02Manganese sulphate0.05Polysorbate 801.0Total41.0*Adjusted/supplemented as required to meet performance requirements