title: Identification of the components of bitespiramycin by liquid chromatography-mass spectrometry.
abstract: Reversed-phase liquid chromatography coupled with electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) was used to characterize the components of bitespiramycin, a group of 4"-acylated spiramycins produced by bioengineered strains. In total 38 components were characterized in commercial samples, including 12 impurities that had never been reported before and 12 other that were partially characterized. The structures of these unknown compounds were deduced by comparison of their fragmentation patterns with those of known major components. Their ultraviolet spectra were used to confirm the presence of an α-, β-, γ-, δ-unsaturated butadiene in the macrocyclic lactone. Compared with the classical method, LC/ESI-MS/MS is particularly advantageous in terms of sensitivity and efficiency to characterize minor components at trace levels in multi-component antibiotics.
authors.affiliation: Department of Antibiotics, National Institutes for Food and Drug control, Beijing 100050, PR China.
authors.forename: Ming-juan
authors.initials: MJ
authors.lastname: Wang
authors.forename: Jing
authors.initials: J
authors.lastname: Xue
authors.forename: Wen-bo
authors.initials: WB
authors.lastname: Zou
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Chang-qin
authors.initials: CQ
authors.lastname: Hu
authors.forename: Jos
authors.initials: J
authors.lastname: Hoogmartens
authors.forename: Erwin
authors.initials: E
authors.lastname: Adams
mesh_terms: D000900:Anti-Bacterial Agents / Q000032:analysis* / Q000737:chemistry; D002853:Chromatography, Liquid / Q000379:methods; D056148:Chromatography, Reverse-Phase / Q000379:methods*; D004340:Drug Contamination; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D015572:Spiramycin / Q000031:analogs & derivatives* / Q000032:analysis / Q000737:chemistry; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D000900:Anti-Bacterial Agents; C503764:bitespiramycin; D015572:Spiramycin