title: In vitro synergistic interaction of 5-O-methylglovanon and ampicillin against ampicillin resistant Staphylococcus aureus and Staphylococcus epidermidis isolates.
abstract: 5-O-methylglovanon (5-O-MG) is a bioactive compound that was first isolated and characterized from Glycosmis plants. In this study, we found that chemically synthesized 5-O-MG has antimicrobial ability against eleven clinical ampicillin resistant Staphylococcus aureus and S. epidermidis isolates. The MICs of 5-O-MG against the S. aureus and S. epidermidis isolates were 12.5-50 μg/mL and 25-50 μg/mL, respectively. In combination with ampicillin, a synergistic interaction between 5-O-MG and ampicillin against the eleven resistant Staphylococcus isolates was observed, with fractional inhibitory concentration indices of 0.03-0125. Moreover, the anti-staphylococcal activity of 5-O-MG in combination with ampicillin was comparable with that of clavulanic acid in combination with ampicillin. The drug combination had no antagonistic effects when tested against any of the strains. Time-killing assays confirmed the synergy between 5-O-MG and ampicillin (p < 0.01). The combination of these two agents yielded greater than a 2 log(10) cfu/mL decrease in comparison with 5-O-MG or ampicillin alone. These findings suggest that 5-O-MG is a promising compound with the potential for future anti-staphylococcal drug development.
authors.affiliation: College of Life Science, Ningxia University, Yinchuan, Ningxia 750021, China.
authors.forename: Xuezhang
authors.initials: X
authors.lastname: Zhou
authors.forename: Fang
authors.initials: F
authors.lastname: Jia
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Liu
authors.forename: Jinhui
authors.initials: J
authors.lastname: Yang
authors.forename: Yuyan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Yujiong
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000667:Ampicillin / Q000494:pharmacology*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D019818:Clavulanic Acid / Q000494:pharmacology; D002969:Clavulanic Acids / Q000494:pharmacology*; D000075202:Contraindications; D004338:Drug Combinations; D024881:Drug Resistance, Bacterial / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects*; D008826:Microbial Sensitivity Tests; D013212:Staphylococcus epidermidis / Q000187:drug effects*
chemical_list: C577802:5-O-methylglovanon; D000900:Anti-Bacterial Agents; D002969:Clavulanic Acids; D004338:Drug Combinations; D004791:Enzyme Inhibitors; D019818:Clavulanic Acid; D000667:Ampicillin