29764
Similarly , the mitochondria of renal tubular cells contain two key enzymes participating in the activation and degradation of vitamin D .
 Chemical: vitamin D
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: vitamin D 
Answer:
 Chemical: vitamin D