Enzymatic Digest of animal tissue, beef extract and yeast extract are the carbon, nitrogen and vitamin sources used to satisfy general growth requirements in Lactobacilli MRS Broth. Dextrose, a fermentable carbohydrate, is absent to allow selection using fifferent carbohydrates. Sodium acetate is an inhibitory agent. Sodium acetate and ammonium citrate act as selective agents as well as energy sources. Potassium phosphate is the buffering agent. Magnesium sulfate and manganese sulfate provide cations used in metabolism. Polysorbate 80 is a surfacant, facilitating uptake of nutrients by Lactobacilli. Applications: Suitable for use in the cultivation of Lactobacilli from dairy products and other materials. Lactobacilli MRS Broth is based on the formulations of deMan, Rogosa and Sharpe (MRS). This medium supports luxuriant growth of Lactobacilli from oral, fecal, dairy and other sources.