21602
Interestingly , 2 showed antioxidant activity by inhibition of ROS generation to 50 % at 33 . 3 mu M in PMA - induced HL - 60 cells , while 1 was inactive at 100 mu M ( vs Trolox 1 . 4 mu M ) .
 Chemical: PMA; Chemical: Trolox
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: PMA; Chemical: Trolox