Isolation And Identification Of Secondary Metabolites From Two Stretomces And The Antibacterial Activitof Resistomcin

Streptomyces can synthesize structurally diverse secondary metabolites, and have good biologicalactivities, which is a class of microbial resources who can produce maximum antibiotics. We took twostrains of Streptomyces as the study object, based on the taxonomic status of the strain, separated andpurificaed its secondary metabolites, identificated the structure of monomer compound, detected biologicalactivity of monomer compounds, and study on the antibacterial mechanism of active monomer compounds,In order to obtain new antibiotics resources, and clear out antibacterial mechanism of the activecompounds.1. Classification and identification of strains TRM44001and the separation and purification from thesecondary metabolitesThe TRM44001was identified as S. erythrogriseus by the ways of morphological and16Smolecular, the extract obtained by the ways of having a large scale liquid fermentation ofstrain, and heating to reflux bacterial cells, and using macroporous resins enrichment way. We isolatedfour compounds from TRM44001by using tetracenomycin Cphase silica gel column chromatography, gelcolumn chromatography, TLC and other separation methods. Identified four compounds wereresistomycin(BM-1),tetracenomycin D(BM-2),L-4-OH-Pro-L-Phe(BM-3),2,2′-tetrahydrosqualene(BM-4),by using the spectrum of1H NMR and13C NMR,and combination with the two-dimensional spectral toanalytical compound structure, these four compounds were first time to isolated from the S. erythrogriseus,and the compounds of L-4-OH-Pro-L-Phe and2,2′-tetrahydrosqualene were the new record ofStreptomyces which could be separated and purificated from.2. Classification and identification of strains TRM44002and the separation and purification from thesecondary metabolitesThe TRM44002was identified as S. tocytricini by the ways of morphological and16S molecular,and the extract obtained by the ways of having a large scale liquid fermentation of strain, and heating to reflux bacterial cells, and using macroporous resins enrichment way. We isolated three compounds fromTRM44002by using tetracenomycin Cphase silica gel column chromatography, gel columnchromatography, recrystallization and other separation methods. Identified three compounds were1-Methyl emodin(44002-1),8-Methyl emodin(44002-2),terrein(44002-3) by using the spectrum of1HNMR and13C NMR,and combination with the HMQC、HMBC、NOESY to analytical compound structure,these four compounds were first time to isolated from the S. tocytricini,3. Study on antibacterial activity and antibacterial mechanism of resistomycinIn this study, we took S. aureus, S. epidermidis, E. coli, C. albicans, V. dahliae, F. oxysporum f sp.Vasinfectum, P. capsici as target bacteria, and measured the antibacterial activity of resistomycin ofmonomeric compounds which were separated from TRM44001. The resistomycin only have strongantibacterial effect to S. epidermidis (MIC=2μg/mL), and there is no antimicrobial effect to other targetbacteria.A preliminary study on the antibacterial mechanism of resistomycin to S. epidermidis showed that, theresistomycin can thus play a role in antimicrobial by inhibiting the dehydrogenase activity, and nucleicacids synthesis, and undermining the integrity of cell membranes to play antibacterial effect. This studyenriched the library of secondary metabolites of S. erythrogriseus and S. tocytricini, provided a new sourceof bacteria for the study of antibiotics such as tetracenomycin D and resistomycin, and offered otherproduction ways of dexamethasone. Preliminary study on the inhibitory mechanism of resistomycin to S.epidermidis, plays a reference role for application of resistomycin type antibiotics, and provides apossibility for the prevention and treatment of mastitis in dairy cows.