The Research Of Active Metabolites Of Strain HCCB11876

Actinomycetes distribute widely in nature, and have large diversities not only in ecology,biology, genetics, but also in inhabit biotopes and living strategy,and their biodiversities heavily determine the diversity of the structures and bioactivities of their secondary metabolites.Nowadays about 70% of clinical antibiotics are produced by actinomycetes. Many important marked medicines can be discovered from secondary metabolites, such as streptomycin 、 daptomycin 、 enramycin 、 ramoplanin and so on.Therefore actinomycetes can be the best resources of discovering new antimicrobial drugs. And the secondary metabolites from actinomycetes have been one of the most important sources of bioactive natural products. In this study, antibacterial metabolites were screened through 96-well plates and disk diffusion and some active metabolites were analyzed by UPLC-MS、HPLC-DAD and compared with known compounds in the library.Finally, some metabolites from the broth of strain HCCB11876 were purified and identified.The results were as follows:1.The 15 active actinomycetes are isolated and purified from 1031 soil actinomycetes,some active strains were screened by three target-guided screening model of E. coli(PHN678, mur G, folp) using 96-well plate. Then the above strains were screened again using the same method in order to verify the activity and stability of therm. Among them, four active strains of them were identified as Streptomyces by molecular method.2.Tunicamycin B1、Tunicamycin C1、Tunicamycin B2、Tunicamycin B3、Tunicamycin D from the broth of strain HCCB11835 were analyzed by UPLC-MS、HPLC-DAD and compared with known compounds in library which did not discovered in other strains.3.Seven metabolites were purified and identified from the broth of Streptomyces sp.HCCB11876 by IR, MS and NMR. Among them, compounds 1-5 are are Qunomycin A( 1),Qunomycin B( 2),Qunomycin C( 3),Qunomycin E( 4),7-S-Oxide-Quinomycin A( 5)and the other two new compounds are 7-S-Oxide-Quinomycin B or named Quinomycin F( 6)and 7-S-Oxide-Quinomycin C or named Quinomycin G(7). All compounds exhibited activities against Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, and Enterococcus faecalis. Structure-activity relationship showed that the activity decreased as the number of methyl group increased.