25366
In in vitro antioxidant study , the free radical scavenging effect of friedelin on 2 , 2 - diphenyl - picrylhydrazyl ( DPPH ) , hydroxyl , nitric oxide and superoxide radicals were evaluated .
 Chemical: friedelin; Chemical: 2 , 2 - diphenyl - picrylhydrazyl; Chemical: DPPH; Chemical: hydroxyl; Chemical: nitric oxide; Chemical: superoxide
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: friedelin; Chemical: 2 , 2 - diphenyl - picrylhydrazyl; Chemical: DPPH; Chemical: hydroxyl; Chemical: nitric oxide; Chemical: superoxide