Nine substances, namely Q, Q1, Q3, Q4, Q5, Ca, Ce, Ck and Cm inhibited HMGR in vitro, of those Q3, Q5, Ca and Ce showed significantly inhibitory effects with IC50 of 11.2 mg / ml (Q3), 3.94 mg / ml (Q5), 13.65 mg / ml (Ca) and 5.28 mg / ml (Ce).