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).

Shelf Life (days)
1095 days

Dehydrated Medium Appearance
Fine Powder

Dehydrated Medium Colour
Straw

Dehydrated PH
6.5 ± 0.2

Prepared Medium Appearance
Liquid

Prepared Medium Colour
Dark Straw

Prepared PH
6.5 ± 0.2

Recommended Incubation
Aerobically at 30 ± 1°C for up to 3 days.