Sources of f/ie Drug 153 



Histologically, the crude chug can be identified by the presence 

 of typical cells. Epidermal cells are rectangular and polygonal, meas- 

 uring 60 microns on the average. The walls are brown and thickened. 

 Ground tissues are full of starch grains, usually simple; if compound, 

 the comjjonents are from two to three parts. Vascular bundles run 

 longitudinally through the corm and are of the collateral type. Xylem 

 vessels are narrow, spiral, or annular, and about 30 mm. in diameter. 



Seeds of Colchicum are subspherical, 2 to 3 mm. in diameter, hav- 

 ing a dark brov^n and rough seed coat. A large, hard, yellow endo- 

 sperm surrounding a small embryo is embedded near the surface of 

 the seed. Strong HCl colors the endosperm yellow, indicating the 

 presence of oils.i'- ^^ The seeds are bitter, but they do not have the 

 same disagreeable odor found with corms. Large enough amounts of 

 colchicine are contained in seeds that poisonous effects can be pro- 

 duced if warm-blooded animals eat a certain (juantity. 



5.6: Compounds Isolated From Colchicum 



From 1901 to 1949, many reports have been made to establish the 

 amount of pure substance to be expected from a given amount of 

 dried raw material. The corm, seed, fruit, and flowers have been 

 studied, and variations recorded. ^s. o<i. f'- Some of the basic reasons for 

 variation have been mentioned. 1 here are sources of variation that 

 occur because different methods of extraction and assay have been 

 used.^' ^0 A survey of some of the literature shows the variety of 

 methods that have been advocated and used.-- •='• •''• ^^- "• ^^^ i**- 1'-*- --• 

 .SI, 33, 3.-., 37, 41, 42, 43, 52, 66, 73 Improvements in methods have come 

 through the use of polarography and chromatography. •^-- ^'i- *^^ A 

 large field of chemistry of plant products has been opened by the 

 application of these new technics to drug plants. The idea that 

 Colchicmn produces only cokhicine must be changed in light of the 

 important compoinids that ap[)car with pure drug.^^ 



The treatment of corms with boiling water during preparation 

 for market causes water-soluble portions to leach out. Difterent solu- 

 bilities and physical properties show that even the so-called pure 

 drug is not a single compound. These impurities have been detected 

 in pollen germination studies. Obviously very few biological experi- 

 ments have been jjerlormed ^vith jjinc colchicine. There are dif- 

 ficulties in making absolutely pine colchicine in large quantity. 



In addition to the comj^ounds obtained from the raw material, 

 there are derivatives made in the laboratory by degradation w^ork 

 from the drug. Enough has been done to prove that specific chemical 

 substances related to colchicine are obtainable. The details of such 

 work are extended in the cha])ter dealing with chemistry of colchi- 

 cine. 



