This study analyzed the thermal stability of lovastatin and citrinin in oyster and king oyster mushrooms during cooking. Samples were cooked in oil at 325F and 425F for 5, 10, 15, and 20 minutes. Extractions were performed and compounds were analyzed using thin layer chromatography. The results showed that citrinin decomposed with heating, while lovastatin remained present. This indicates that cooking helps remove the toxic citrinin while preserving the beneficial lovastatin.

1. Thermal Stability
of Lovastatin and
Citrinin in
Pleurotus ostreatus
and P. eryngii
Common Name: Oyster Common Name: King Oyster
Common Name: Oyster Common Name: King
Oyster

2. Experiment Significance
This experimental procedure stemmed from an original study concerning the
presence of the cholesterol lowering organic compound lovastatin and
mycotoxin citrinin in red yeast rice
Pleurotus ostreatus (oyster) and P. eryngii (king oyster), both commercially
cultivated fungi, also contain lovastatin and citrinin
Both are typically roasted (in oil) before consumption, necessitating an analysis of
the thermal stability of lovastatin and citrinin
Temperature of complete citrinin dissipation is of particular interest

3. Citrinin- C13H14O5
Citrinin was first isolated as a pure compound from a culture of Penicillium citrinin
in 1931.
A nephrotoxic mycotoxin that is produced by several fungal species as well as
many cereals and barley usually found with another mycotoxin called
Ochratoxin A.
In early studies, citrinin has been found to have strong antibacterial properties,
but was ruled out upon discovering its potential to target and damage the
kidneys in the form of fatty infiltration that cause the kidneys to swell and
followed by eventual necrosis.
The objective of our research is to find and decompose the citrinin without also

4. Lovastatin- C24H36O5
A lactone metabolite and common prodrug (metabolized into
pharmaceutically active form after consumption)
Inhibits the HMG-CoA reductase, an enzyme which increases the rate of
mevalonate production within the biosynthetic pathway of cholesterol
Experiment intends to analyze the extent (if any) of thermal decomposition of
lovastatin in samples

5. Cooking
Gather dry oyster and king oyster mushrooms.
Soak dry mushrooms in water for 20 minutes, drain and toss them in oil.
Place them on a piece of aluminum foil and insert them in the oven at 325℉.
The samples were removed at 5-minute intervals. (5-min, 10-min, 15-min, and 20-
min.)
To stop additional cooking, place the hot mushrooms onto a pan resting in an ice
bath to rapidly drop the temperature.
Once cooled, wrap the mushrooms with a paper towel and place them in a Zip-

6. Extractions:
1. Rinse mushroom samples cooked in oil with Hexane twice.
2. Add a small amount of mushroom sample and 8:2mL Methanol-Water solution
in a test tube.
3. The test tubes were placed in the sonicator for 15 minutes.
4. Once done, the solution goes through vacuum filtration. Approximately 5-mL of
distilled water was used to rinse.

7. 5. The extracted liquid solution was placed in a separatory funnel.
6. Add 15-mL of Dichloromethane (Methyl Chloride)
7. Shake the separatory extractor and release the built up pressure. Repeat 3 times. Let it settle.
8. Extract the bottom layer into a 50-mL Erlenmeyer flask and place stopper.
9. Repeat step 6 - 8 for a second extraction.
10. Repeat steps 6 - 9 for every sample.

8. 11. The solutions collected in the Erlenmeyer flasks were placed in a 100-mL beaker
which was then placed in a hot water bath.
12. We allowed the solution to evaporate completely in order to perform TLC.

9. Thin-Layer Chromatography (TLC)
On the HPTLC plate, lightly mark a line using a pencil about 1 inch from the
bottom going across the plate.
Add 2 drops of dichloromethane into the evaporated solution beaker.
Swirl around and then using 1-5 microliter pipette, collect the sample and spot it
on the HPTLC plate.
Do this for each sample.

10. On the plates…
Plate 1: Citrinin and Lovastatin
control dry oyster and king
control oil oyster and king
325℉ oil oyster at 5, 10, 15, 20 minutes.
325℉ oil king at 5, 10, 15, 20 minutes
Plate 2: Citrinin and Lovastatin
control dry oyster and king
control oil oyster and kind
425℉ oil oyster at 5, 10, 15, 20 minutes
425℉ oil king at 5, 10, 15, 20 minutes

11. In the chamber...
Place the plates into the TLC chamber with the TLC solution and cover.
Allow the solution to travel up the plates.
Once the solution is all the way to the top, place the plates under the fume hood
to dry.

12. In the light.
Once dry, shine a short
wavelength UV light and
then a long wavelength UV
light to see results.

13. Analysis
Results:
At both experimental temperatures, Lovastatin was still present and Citrinin decomposed.
These results are positive because Lovastatin has beneficial properties and
Citrinin has negative properties.

14. Conclusion
- Utilized an existing, validated extraction procedure
- TLC solution proved our uncertainty of how much citrinin is remaining.
Lovastatin is still in the remaining sample.
- This knowledge will aid in future issues with consumption
- Found that heating (with oil) helps remove citrinin, but does not affect the
levels of Lovastatin remaining