Researches On Secondary Metabolites And Activities From Three Plant Endophytic Fungi And Two Soil Streptomyces Strains

Screening drug from natural products is an important way to search and develop new drugs.Nowadays,the vast majority of antibiotics are derived from the metabolites of actinomycetes and fungi,in the pharmaceutical market.In the clinical drugs,antibiotics such as penicillin and cephalosporin,and statin-hypolipidemic drugs are produced from the metabolites of fungi.They are streptomycin,oxytetracycline,antitumor bleomycin and mitomycin,antifungal nystatin,kanatycin of anti-tuberculosis,etc.that are all derived from streptomyces.So,fungi and actinomycetes have been an important source of clinical small molecule drugs.In order to find the novel and active metabolic products,the fungi and actinomycetes isolated from different habitats were studied,in this paper.The structure and activities of its secondary metabolites were studied.In the text,screen the strains by fermentation of strains and then HPLC analysis the metabolite.Five strains with abundant products and large yield were selected.They are Streptomyces sp.KIB-Hjusi and KIB-H1666,fungus KIB-H11545,KIB-H11590 and KIB-H11595.The separation means are silica gel column,gel chromatography column(Sephadex LH-20)and HPLC.The primary extract of the secondary metabolite of the strain is isolated and purified,by the above means.Then,the structures of compounds are determined by means of NMR and MS.Results of the study,ten compounds were isolated from KIB-Hjusi,seven compounds of which were phenazine carboxylic acids,and five compounds were new phenazine carboxylic acids;Four compounds were isolated from KIB-H1666,and compound 13 was a new structure;Six known Anthraquinones were isolated from KIB-H11595;Three known naphthalenone compounds were isolated from KIB-H 11545;Four compounds of known structure were isolated from KIB-H 11590.The compounds were subjected to a targeted antifungal test using a filter paper method.The results showed that compounds 13 and 14 have strong antibacterial activity against the selected test strains[Fusarium oxysporum vasinfectum,Penicillium,Fusariurnoxysporum.sp.Cucumebrium Owen,Rhizotonia solani,and Curvularia lunata(Walk)Boead].Compound 15 has a bacteriostatic effect on Penicillium.Compound 19 has a certain inhibitory effect on Fusarizum oxysporum vasinfectum.Compound 20 has a certain antibacterial effect on Penicillium.Compounds 21 and 22 have certain antibacterial activity against Fusarium oxysporum vasinfectum,and compound 22 also has a certain inhibitory effect on Fusarium oxysporum vasinfectum.Compounds 24 and 25 have certain antibacterial activity against Curvularia lunata(Walk)Boed.