82 PHARMACEUTICAL BOTANY 



in corn starch are absent. The grains take on a red coloration with 

 iodine solutions. 



5. Amylodextrin. This is a carbohydrate intermediate in proper- 

 ties between starch and dextrin. It occurs in the form of small ir- 

 regularly shaped granules, in Mace, that take on a reddish brown to 

 reddish violet color with iodine solutions. 



6. Inulin. Inulin is a carbohydrate isomeric with starch which 

 has the chemical formula of Ci 2 H 20 Oio. It is found dissolved in the 

 cell sap of many plants, especially those of the Composite. If pieces 

 of a plant part containing this substance be placed directly in alcohol 

 for at least a week, then sectioned and mounted in alcohol, sphaero- 

 crystals of inulin will be seen applied to the walls of the cells. When 

 these sections are treated with a 25 per cent, solution of alpha 

 naphthol and 2 or 3 drops of strong H 2 SO 4 , the sphaerocrystals will 

 dissolve with a violet color. Fehling's solution is not reduced by 

 inulin. 



7. Hesperidin. Hesperidin is a glucoside having the chemical 

 formula of C 2 iH 2 eOi 2 . Like inulin it occurs in solution within the 

 cell sap. It is found in abundance in the Rutaceae family but occurs 

 in many other plants. If sections of alcoholic material containing 

 this substance such as Buchu leaves or unripe orange peel, are 

 mounted in alcohol and examined, sphaerocrystals will be seen. If 

 these are then treated with a drop of alpha naphthol solution and 2 

 or 3 drops of strong H 2 SO 4 , they dissolve with a yellow color. The 

 same coloration is evident when 5 per cent, solution of KOH is 

 substituted for the alpha naphthol and H 2 SO 4 . 



8. Strophanthin. This is a glucoside occurring in the cell sap of 

 the endosperm of Strophanthus Kombe, S. hispidus and other species 

 of Strophanthus. If sections of fresh Strophanthus seeds are 

 mounted in a drop of water and then transferred to a drop of con- 

 centrated H 2 SO 4 , the cells containing Strophanthin will assume a 

 bright green color. 



9. Salicin. Salicin is a glucoside occurring in the cell sap of the 

 bark and leaves of the Willows and Poplars. Sections of these 

 mounted in concentrated H 2 SO 4 will show a red coloration in the 

 cells containing this substance. If water be added a red powder is 

 thrown down. 



