17194
Over the last decade , many studies have demonstrated the anticancer activity of alpha - tocopherol , the main and most active form of natural vitamin E .
 Chemical: alpha - tocopherol; Chemical: vitamin E
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: alpha - tocopherol, vitamin E 
Answer:
 Chemical: alpha - tocopherol; Chemical: vitamin E