Purification And Bioactivity Of The Secondary Metabolites Produced By Five Streptomyces Sp.

The secondary metabolites of Streptomyces,as main sources of antibiotics,are important components of active natural products and possess tremendous value in pharmaprojects.The constituents of fermentation broth from five soil Streptomyces sp.were studied in this experiment.All compounds were isolated by silica gel column,Sephadex LH-20 column and pre-HPLC from the fermentation broth of five soil-derived Streptomyces here,and their structures were identified by the means of various spectroscopic evidences,such as,¹H-NMR,¹³C-NMR,¹H-¹H COSY,HSQC,HMBC,NOESY,MS,CD and X-ray.The bioactivity of partial compounds also studied and discussed here.The results of this study are summarized as follows:1.Sixteen compounds,including twelve angucyclinones（1-12）,were isolated from the fermentation broth of Streptomyces sp.KIB-M10.Compounds 1-8 were reported here for the first time and 5-8 featuring C?Ring cleavage in the skeleton of angucyclinones.The absolute configuration of elmycin A（9）and elmycin B（10）was confirmed by crystal structure for the first time in this test.The other four compounds were identified as fuzanins C,fuzanins D,indole-2-carboxylic acid and salvinin A,respectively.Compound 3 showed significant bacteriostatic activity to Staphylococcus aureus ATCC 6538,Escherichia coli ATCC 8099and Bacillus subtilis ATCC 6633,and the diameter of inhibition zone was even larger than that of the positive control kanamycin.Compound 11 also exhibit moderate antibacterial activity.2.Eighteen alkaloids（17-34）,including seven new compounds（22-28）,were isolated from the fermentation broth of Streptomyces sp.KIB-1663.These compounds comprise pyrrolizidine,indolizidine,quinolizidine,glycoside,cyclic dipeptide and so forth.Dibohemamine A（20）and dibohemamine F（21）had moderate antibacterial activity against Staphylococcus aureus ATCC 6538,Bacillus subtilis ATCC 6633,yeast and Monilia albican.3.Fourteen compounds（35-48）,including seven macrolides were isolated from the fermentation broth of Streptomyces sp.KIB-K1.These macrolides including five aldgamy-cins:aldgamycin J（37）,aldgamycin K（38）,aldgamycin L（39）,GERI-155（40）,chalcomy-cin（41）;And two chalcomycins:aldgamycin E（36）and a new compound,aldgamycin P（35）.All macrolides exhibit distinct inhibitory effect aganist Staphylococcus aureus ATCC6538,Bacillus subtilis ATCC 6633.The minimal inhibit concentration（MIC）of compound1 to S.aureus was 7.81μg/m L.The MIC of compounds 2 and 7 to S.aureus were 0.49μg/m L and 0.98μg/m L,respectively,which was higher than that of positive control kanamycin with MIC of 3.91μg/m L.4.Seven compounds,13-hydroxylpentalenic acid（49）,pentalenic acid（50）,N-Acetyltyramine,oxazolomycin（52）,cyclo-（S-Pro-R-Leu）（53）,cyclo-（S-Pro-S-Ile）（54）,2-Phenylacetamide,were isolated from the fermentation broth of Streptomyces sp.KIB-4439;Four virginiamycins,two known compounds,virginiamycin M1（56）,virginiamycin M1516（57）and two new compounds,virginiamycin M2a（58）and virginiamycin M2b（59）were isolated from the fermentation broth of Streptomyces sp.KIB-4501.Those virginiamycins（56-58）had significant antibacterial activity against S.aureus ATCC 6538,B.subtilis ATCC 6633 and E.coli ATCC 8099.In total,59 compounds,including 19 new compounds（1-8,22-28,35,49,58 and 59）,were isolated from five soil Streptomyces strains.The bioacivity test showed that compounds3,11,20,21,35-41,and 56-58 had significant antibacterial activity.