30507
To elucidate the pharmacophore of echinocystic acid ( EA ) , an oleanane - type triterpene displaying substantial inhibitory activity on HCV entry , two microbial strains , Rhizopus chinensis CICC 3043 and Alternaria alternata AS 3 . 4578 , were utilized to modify the chemical structure of EA .
 Chemical: echinocystic acid; Chemical: oleanane; Chemical: triterpene
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: echinocystic acid; Chemical: oleanane; Chemical: triterpene