MSA

Dr. Spencer explains that a non-selective medium is needed in this case. MSA is selective for Gram-positive bacteria, particularly staphylococci, due to its high salt concentration, which inhibits most other bacteria. It also differentiates based on the fermentation of mannitol. 

Website: https://www.shutterstock.com/image-photo/s-sepidermidis-on-mannitol-salt-agar-1522128641 

Although valuable for identifying Staphylococcus aureus in certain contexts, it is not ideal for detecting general bacterial contamination, as it excludes many bacterial types that might be present in a diverse sample. Let’s try again!