5721
The photosensitizer , methylene blue ( MB ) , generates singlet oxygen ( ( 1 ) O2 ) that irreversibly inhibits Torpedo californica acetylcholinesterase ( TcAChE ) .
 methylene blue, oxygen, O2
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 methylene blue, oxygen, O2