Recently swim did this pretty straightforward extraction that produced surprisingly low yield.

1. 50 g of fine mhrb powder were soaked in 96% ethanol for 3 days.
2. Mhrb was extracted in swim's home-made extractor until the ethanol in the extraction tube became completely clear (~3 hrs).
3. Most of the ethanol from the boiling flask has been distilled.
4. The extract has been reduced as much as possible (~30 ml of thick dark purple goo).
5. The extract has been dissolved in acidified water (pH ~4.5).
6. The solution has been left to settle down for half a day, decanted and filtered until completely clear. Solids were discarded.
7. The solution was basified to pH ~11.3 with diluted NaOH.
8. Swim did 5 hexane pulls under room temp using a sep funnel. Altogether she got 150 ml of colorless clear hexane.
9. Combined Hexane pulls were reduced to 20 ml. At this point hexane became very cloudy.
10. Remaining hexane was sealed with food wrap film and moved to a fridge and later to a freezer.
11. After 12 hours only 120 mg of absolutely white sticky tiny crystals were collected. ATM yield is only 0.24%.

All used chemicals were of reagent grade. All the procedures were executed quite carefully using standard lab glassware. There were no obvious screw-ups. Earlier the same powder produced 0.8-0.9% of good spice, although admittedly less pure.

Anybody got an idea where the spice might be hiding?

Swim has forgotten the Hexane collected after freeze-precip on a windowsill and it has evaporated completely leaving another 10 mg of pure spice. Yield is still very low - 0.26%.

Swim plans to add more lye to the basic solution raising its pH to 12.5 and doing 5 more small Hexane pulls.