Yeast extract is the water-soluble portion of autolyzed yeast, often used in culture media. Yeast extract contains a mixture of amino acids, peptides, water soluble vitamins and carbohydrates.
Yeast extract is used in all solid media, on which stock cultures are maintained, due to its ability in promoting growth of most bacterial contaminants, thereby making them visible to identify. Yeast extract does not enhance the growth of wild-type cells but essential for auxotrophic mutants.
Suitable for use as nutritional source in microbial media.
Select Yeast Extract has been used as a supplement in the minimal sporulating medium (MSL) for the secretory production of human tumor necrosis factor-α (TNFα) using the carboxypeptidase Y (Cpy) signal peptide. It has also been used in the isolation of halophilic archaea.