Yeast Organic Extraction for LC-MS
This protocol outlines a quick and simple procedure for extracting all organic compounds from a yeast culture for subsequent analysis via Liquid chromatography–mass spectrometry (LC-MS). It is suitable for quickly assessing the presence of products from small sample preps.
Organic solvents: Ethyl Acetate, Acetone, Acetic Acid and Methanol
- Grow yeast in selective medium overnight.
- Inoculate a 30mL YPD culture to a final OD600 of ~0.2.
- Grow at 30°C, shaking at 200 rpm.
- At day 3 and/or 4, harvest 2mL of culture in 15 mL Falcon tubes. Spin down.
- Move the supernatant to a new tube and add 2mL of ethyl acetate. Mix by vortexing and incubate at RT overnight.
- For the pellet, add 1mL of acetone and 1mL of ethyl acetate. Mix by vortexing and incubate at RT overnight.
- For unknown compounds, consider adding vol/vol 1% of acetic acid.
- Take 0.5 mL from each extraction, avoiding pellet or particulate matter. Speed vacuum at RT until completely dry.
- Redissolve in 200µL of methanol. Load 5-8µL on LC-MS.