Dear Dr. Shulgin:
A friend of mine performed a Soxhlet extraction of 12 grams of powdered Psilocybe cubensis, using 95% ethanol. When the 60 mL of extract cooled to room temperature, many small transparent, colorless crystals had formed on the bottom of the container and did not redissolve on agitation. Do you know what these crystals are? -- Journeyman
Dear Journeyman:
There is a fascinating report in the literature that gives a quantitative measurement of the efficiency of extraction of both psilocybin and psilocin from the mushroom Psilocybe bohemica. The citation to the article is Kysilka, R. and Wurst, M., Planta Med. Vol. 56 pp. 327-328 (1990). These Czechoslovakian scientists studied the efficiency of both methanol and ethanol as solvents, each containing varying amounts of water. The results were, to me, both unexpected and most provocative.
The isolation of psilocybin seemed to be quite reasonable. This alkaloid is reasonably soluble in boiling water from which it can be nicely crystallized. It is less soluble in boiling methanol, and almost insoluble in boiling ethanol. And the extraction efficiency is optimum with methanol and almost as good with ethanol. With both, the less water present, the better. The compound is, after all, a perfect example of a zwitterion, the internal salt of a phosphoric acid and an amine base.
But the numbers with psilocin are strange. With aqueous ethanol, the optimum extraction was with a 70% ethanol concentration, and the extraction efficiency dropped almost to zero when there was no water present. But methanol was extremely inefficient regardless of the amount of water present in it. These researchers were apparently surprised by these findings, as they explored further and uncovered other clues. Time is a factor. Psilocin is extracted at a much slower rate than is psilocybin because it is contained intracellularly in the plant, and thus slower to be gotten out. They conclude that many of the low psilocin assays of mushrooms are due to this difficulty of getting the alkaloid out of the plant and into the extracting solvent. Using this information they determined that the levels of psilocybin and psilocin are substantially the same in Psilocybe bohemica, in conflict with the published literature values where very small amounts of psilocin were observed.
Efficient extraction apparently requires patience.
As to the identity of the crystals that were drifting around in the cooled Soxhlet receiver, from their being insoluble in ethanol, and white, and transparent, I would guess that you are seeing pure psilocybin.
-- Dr. Shulgin
