23840
The combined effects between essential oils of cinnamon bark , lavender , marjoram , tea tree , peppermint and ampicillin , piperacillin , cefazolin , cefuroxime , carbenicillin , ceftazidime , meropenem , were evaluated by means of the checkerboard method against beta - lactamase - producing Escherichia coli .
 Chemical: ampicillin; Chemical: piperacillin; Chemical: cefazolin; Chemical: cefuroxime; Chemical: carbenicillin; Chemical: ceftazidime; Chemical: meropenem
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: ampicillin; Chemical: piperacillin; Chemical: cefazolin; Chemical: cefuroxime; Chemical: carbenicillin; Chemical: ceftazidime; Chemical: meropenem