| Actinomycete is an important microbial resource widely distributed in nature,among which Streptomyces is the most abundant.The secondary metabolites of Streptomyces Streptomyces are rich in variety,novel in structure and good in biological activity,which are important sources of new antibiotics.With the development of sequencing technology and bioinformatics,scientists have realized that a large number of gene clusters in Streptomyces are silent,which means that there are still a large number of new active natural products in Streptomyces that need to be discovered.In this paper,two strains of soil streptomyces NA07424,NA07292 and one strain of marine streptomyces NA07600 were studied.NA07424 was identified as Streptomyces pseudovenezuelae by analysing 16 S r RNA gene sequence information.We used YEME medium for large-scale fermentation and employed a combination of chromatographies over normal-phase silica gel and reverse-phase ODS silica gel,Sephadex LH-20 and HPLC to separate.Finally,we obtained 9 compounds(1-9)including 3 new compounds(1-3)which were confirmed by spectra analysis including LC-MS、NMR、IR、UV、CD and Marfey’s reaction.These compounds were proved to have good activity against oxidative stress.After repeating the same methods for NA07600 and NA07292,we obtained 7 compounds(10-16)including 3 new compounds(12,14,16)which were polyketide compounds.The research results show that intensive study on the secondary metabolites of the three strains not only obtained different types of new compounds,but also got compounds with good activity.These compounds with good activity laid a foundation for new drug discovery.In addition,the structural characteristics,biological activities and biosynthetic pathways of peptides produced by actinomycetes were reviewed in this paper. |
