19403
The commonly - used chromogenic substrate gamma - glutamyl - p - nitroanilide was also tested .
 Chemical: gamma - glutamyl - p - nitroanilide
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: gamma - glutamyl - p - nitroanilide