de Man- Rogosa- Sharpe-medium with Durham tube (MRS)
This substrate is used for profuse growth of lactic acid/micro-aerophilic bacteria. It has been enriched with yeast extract to allow bacteria with high nutritional requirements to grow. The medium can be used to determine whether a bacterium is homo- or heterofermentative if an inverted Durham tube is added. Homofermentative bacteria do not produce gas from the fermentation of glucose, heterofermenters do. 1. Uninoculated medium. 2. Growth with gas production: Lactobacillus brevis. 3. Growth without gas production: Lactobacillus salivarius.
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