13964
When the strain was grown in the presence of 1 , 4 - butanediol ( BDO ) as a 4HB precursor , P4HB block was formed .
 Chemical: 1 , 4 - butanediol; Chemical: BDO; Chemical: 4HB; Chemical: P4HB
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: 1 , 4 - butanediol; Chemical: BDO; Chemical: 4HB; Chemical: P4HB