Isolation And Identification Of Secondary Metabolites From Two Antitumor Actinomycetes

Antitumor antibiotics are widely used in clinical practice,but there are still some problems,such as drug side effects and tumor cell multi-drug resistance?MDR?.In order to find novel antitumor compounds to solve the problem,the study was carried out to screen antitumor soil actinomycetes and isolate secondary metabolites from two actinomycetes fermentation broth by activity tracking method.Two active strains were screened from soil actinomycetes by detecting the in vitro antitumor activity against human lung cancer cell A549 and human colon cancer cell HCT-116.The two strains were identified Streptomyces though 16 S r RNA data and named Streptomyces sp.HS-NF-1006 and Streptomyces sp.HS-NF-853,respectively.Considering the result of screening antitumor soil actinomycete and the growth status of strains in different medium,the medium consiting of glucose 1%,soluble starch 4%,yeast extract 0.4 %,malt extract 0.1%,Ca CO₃ 0.2%,FeSO₄·7H₂O 0.1%,Mn Cl₂·4H₂O 0.1% was choosed as the optimum fermentation medium for Streptomyces sp.HS-NF-1006,the medium consisting of glucose 1%,soluble starch 4%,yeast extract 0.4%,maltodextrin 1%,0.1 ml/L?Fe SO₄·7H₂O 0.1%,MnCl₂·4H₂O 0.1%,ZnSO₄·7H₂O 0.1%?was chosen as the optimum fermentation medium for Streptomyces sp.HS-NF-853,the fermentation was carried out in a fermenter?50 L?.With the use of silica gel,LH-20 and HPLC,then the isolation of the fermentation broth was taken on.9 compounds were finally obtained,and their structures were elucidated on the basis of MS spectrum and NMR spectrum analysis.3 compounds were obtained from the fermentation broth of Streptomyces sp.HS-NF-1006,and the 3 compounds were belong to anthracene antibiotics,among them compound 1 was a novel compound and named 13-oxy-13-decarbony-6??-cyano-6??-deoxy-TAN-1120.6 compounds?4-9?were obtained from the fermentation broth of Streptomyces sp.HS-NF-1006.Compound 4 was a novel tetrahydrobenzofuranone derivative,named strefuranone A.the cytotoxicity of compound 1 against human lung cell line A549 and human colon cancer cell HCT-116 was strong,and IC₅0 values were 0.08 ?M and 0.0978 ?M respectively.Compound 2-9 displayed no cytotoxicities.