After total of 24 days growth period the culture should be considered mature. Make the culture acidic with tartaric acid and homogenize in a blender for one hour. Extract again with alcoholic tartaric acid and evaporate in a vacuum to dryness. To recover the free base for extraction of the amide of synthesis to LSD, make the tartrate basic with ammonia to pH 9, extract with chloroform and evaporate in vacuo. If no source of pure Claviceps purpurea fungus can be found, it may be necessary to make a field trip to obtain the ergot growths from rye or other cereal grasses.
Rye grass is by far the best choice.
From these heads of ergot sprout the Claviceps purpurea fungi. They have long steams with bulbous heads when seen under a strong glass or microscope. It is these that must be removed from the ergot, free from contamination, and used to inoculate the culture media. The need for absolute sterility cannot be overstressed. Consult any elementary text on bacteriology for the correct equipment and procedures.