Study On The Separation And Purification And Identification Technology Of Daptomycin Impurity Components

Daptomycin is a new lipopeptid antibiotics extracted from fermentation broth of streptomyces roseosprus,which has powerful rasistance to gram-positive bacteria.It is a new type of antibiotic followed by“the last line of denfense for antibiotics”,Vancomycin.In order to further improve the product quality and make them into the foreign markets smoothly,the in-depth study on Daptomycin impurities which produced in the production has important significance.During Daptomycin synthesis process,six impurities,such as impurity C,D,E,lactone hydrolysate,?-isomer and dehydration daptomycin would be produced accompanied by the main product.In this study,the test method of Daptomycin and related substances was firstly set up,and the specificity of solution stability,detection,loq,precision,linearity,durability,and accuracy of the method was verified.The results proved that the organic impurities of Daptomycin could be accurately quantitative determined by this method.The six impurities were separated and purification,their structures were qualitatively analysed and identified.Finally,the molecular formulas was confirmed that:lactone hydrolysate,C₇₂H₁₀₃N₁₇O₂₇;?-isomer,C₇₂H₁₀₁N₁₇O₂₆;dehydration,C₇₂H₉₉N₁₇O₂₅;impurity C,C₇₄H₁₀₄N₁₇O₂₇;impurity D,C₇₃H₁₀₄N₁₇O₂₆;impurity E,C₇₄H₁₀₂N₁₇O₂₆.Further more,the formation mechanism of impurities is analyzed by their structure,and the results indicated that?-isomer and dehydration products are tend to generate under hyperthermia and acidic condition;lactone hydrolysate is tend to generate under hyperthermia and alkaline condition;impurity C and E is tend to generate under hyperthermia condition;impurity D is produced during the fermentation process.Therefore,during the extraction process,insulation material was added around the production equipment pipeline to maintain the temperature lower than 25?.On the other side,flow speed was installed and the flow of acid-base regulating was stabilized at0.6ml/min.Through the above means,the concentration of dehydration,lactone hydrolysate,?-isomer,impurity Cand impurity E decrease by0.24%,0.19%,0.12%,0.14%and 0.04%,respectively.And the dehydration could be controlled lower than 1.5%,lactone hydrolysate?1.0%,?-isomer?1.0%,impurity C?1.0%,impurity D?1.0%,impurity E?1.0%,respectively,which could meet the requirement of Daptomycin production.