21503
VOCs having the greatest enhancement over background were glucic acid from levoglucosan , glycolic acid from abietic acid , and methanol and nitric acid from nitroguaiacol .
 Chemical: glucic acid; Chemical: levoglucosan; Chemical: glycolic acid; Chemical: abietic acid; Chemical: methanol; Chemical: nitric acid; Chemical: nitroguaiacol
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: glucic acid; Chemical: levoglucosan; Chemical: glycolic acid; Chemical: abietic acid; Chemical: methanol; Chemical: nitric acid; Chemical: nitroguaiacol