Dear

According to Spearman et al. 2016 Yeast extract is defined as media additives that support the growth and productivity of CHO cells.

I add you some helpful links:

https://www.ncbi.nlm.nih.gov/pubmed/27165505

https://www.tekniscience.com/documents/Yeast_Extract-19512.pdf

https://www.dsm.com/content/dam/dsm/foodandbeverages/en_US/documents/DFS/eurasyp-brochures.pdf.

http://www.sigmaaldrich.com/analytical-chromatography/microbiology/microbiology-products.html?TablePage=8657623

https://pubchem.ncbi.nlm.nih.gov/compound/24973165

Thank you Marius... It will help me a lot

Hi there,

A defined media is the one for which you know the exact composition. Yeast extract can't be used for the preparation of a defined media as it is actually the result of the hydrolysis of yeast cells. As a result it contains a lot of different molecules and the exact composition of yeast extract is not actually known and may vary from one batch to the other and from one company to the other.

Therefore yeast extract is an ingredient for complex media.