Screening Of Marine Actinomycetes Producing Antimicrobial Substances And Study On Their Secondary Metabolites And Activities

Bacterial resistance increase serious threats to global health care system,in order to cope with the problems,must find a new mechanism of the new type of effective antibiotics,most antibiotics are derived from actinomycetes,so we focused on marine actinomycetes,marine because of its unique environment,provides various active the discovery of lead compounds with rich resources,are more likely to find new antibiotics.In order to gain new structure from marine actinomycetes secondary metabolites and antimicrobial activity compounds,with 12 strains of marine actinomycetes as the research object of this research,through chemical method of filtering and active filtering,filter out two products rich plant secondary metabolites and antimicrobial activity of strains,and antibacterial activity oriented,thin layer chromatography,silica gel column chromatography,gel Sephadex LH-20 column chromatography,and the preparation of liquid chromatography and other separation and purification technology,obtained 18 compounds from the two marine actinomycetes,The structures of these compounds were determined by NMR,MS,UV and other modern spectral techniques.Thirteen compounds were isolated from Streptomyces sp.62JF-7,including seven macrolides:11,11'-O-dimethylelaiophylin(1),11,11'-O-dimethyl-14'-deethyl-14'-methylelaiophylin(2),2-methyl-elaiophylin(3),11-O-monomethylelaiophylin(4),elaiophylin(7),efomycin G(8),2-dimethyl-elaiophylin(9),two macrolide compounds:azalomycin F4a(11)and azalomycin Fsa(12),two monoglycerides:1-linoleoylglycerol(6)and glycerol monooleate(10),two acids:dehydroabietic acid(5)and 13-methyltetradecanoic acid(13).Five compounds were isolated from Streptomyces sp.92JF-1,including four macrocyclic lactams:geldanamycin(14),17-O-demethylgeldanamycin(16),reblastatin(17)and autolytimycin(18),and one macrolilactone compound oxohygrolidin(15).The antimicrobial activity of compound 1-6 and compound 8-18 against five pathogenic bacteria,including Staphylococcus aureus,Escherichia coli,Acinetobacter baumannii,Pseudomonas aeruginosa and Klebsiella pneumoniae,were tested.The results showed that the compounds had no obvious activity against gram-negative bacteria(Escherichia coli,Acinetobacter baumannii,Pseudomonas aeruginosa and Klebsiella pneumoniae).Macrolide compounds 1,2,3,4,8,9,and azamycin compounds 11 and 12 have strong activity against Staphylococcus aureus.