The chemical constituents from the active fractions of Eleutherine bulbosa with their antimicrobial activity.

Six compounds including three new polyketide ones named eleubosas A-C ( 1 - 3) were isolated from the active frations of Eleutherine bulbosa . Their structures were elucidated by extensive spectroscopic methods, including NMR, MS and IR spectroscopic analyses data. All the isolates were evaluated against three pathogenic bacteria, Staphylococcus aureus , Escherichia coli , and Pseudomonas aeruginosa , and the results showed that compounds 1 and 2 displayed moderate inhibitory activities against E. coli with MIC values both 12.5 μg/mL, which are consistent with the clinical applications and need further studies.