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Xanthurenic acid ( XA ) , a molecule arising from tryptophan metabolism by transamination of 3 - hydroxykynurenine , has recently been identified as an endogenous Group II ( mGlu2 and mGlu3 ) metabotropic glutamate ( mGlu ) receptor ligand in vitro .
 Chemical: Xanthurenic acid; Chemical: tryptophan; Chemical: 3 - hydroxykynurenine; Chemical: glutamate
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: Xanthurenic acid; Chemical: tryptophan; Chemical: 3 - hydroxykynurenine; Chemical: glutamate