21176
A highly potent inhibition of the peroxidase catalytic reaction by NO / SNO was seen in assays employing the coupled Prx - Trx system .
 Chemical: NO; Chemical: SNO
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: NO, SNO 
Answer:
 Chemical: NO; Chemical: SNO