Chemical Investigations Into Five Strains Of Microorganisms And Their Biological Activities

Microorganisms are general term for all small organisms that are invisible to the naked eye or cannot be seen clearly.It includes the prokaryotic actinomycetes,eukaryotic fungi and so on.Antibiotics produced by microorganisms play an important role in human medicine.Among them,actinomycetes and fungi are rich in species,easy to be cultured,and have a short growth cycle.They are important resources for the discovery of lead compounds with diverse structures,novel skeletons and remarkable activities.Endophytic fungi is to point to in the life cycle of a certain stage or the whole stage,in the intercellular space of life in healthy tissue and organs or cells and does not cause any apparent host disease symptoms of fungi,some lichens and mosses,as a kind of special habitat source of lower plants,the endophytic fungi have the potential to produce new structure type,more targets unique natural products;Lichen actinomycetes and zoonotic symbiotic fungi,as a new type of resources,have been paid more attention by researchers.In this study,a total of 12 strains of fungi were purified from lake soil and earthworm.Some of the secondary metabolites of fungi showed cytotoxic and antimicrobial activities,and 6 strains of fugi were selected as the system isolates.The chemical constituents and biological activities of five strains of microorganism were systematically studied.Based on the preliminary bioactivity screening and chemical composition analysis results,five strains of Penicillium sp.(No.0141a),Streptomyces sp.(No.0630c),Penicillium sp.(No.L-7-2),Aspergillus tubingensi(No.SQ10)and Hypocrea lixii(No.BQ3)were selected for amplification fermentation and ethyl acetate extraction.Streptomyces sp.(No.0630c)was amplified by YMG medium based on the OSMAC strategy.The crude extracts of the secondary metabolites of five microorganisms’ strains were systematically separated by silica gel column chromatography,gel column chromatography,ODS column chromatography,medium and low-pressure column chromatography and high-performance liquid column chromatography.A total of 58 compounds were obtained,of which 13 were new compounds.The planar structure and three-dimensional configuration of the compounds were determined by nuclear magnetic resonance,mass spectrometry and ECD.From lichen endophytic fungus Penicillium sp.(No.0141 a)of rice in the three compounds were isolated from fermented product,including a benzene and poly ketone compounds(1),and 1 of new poly ketone compounds(2-3),the evaluation of cytotoxicity and antifungal activity,it is a pity that No activity is detected,Lichen actinomycetes from Streptomyces sp.(No.0630c)in the YMG product separation by nine compounds,including three anthracene ketone compounds(4-6)and six alkaloids compounds(7-12),including four for new compounds,and according to the structure characteristics of its biosynthetic pathway has carried on the rational speculation.Cytotoxic activity tracking results indicate that the anthracene ketone compounds 4-6 is the main cause of the strains were cytotoxic activity.Also inhibit bacteria activity experiments show that the compound 5-7 showed obvious inhibition of S.aureus active,compound 7 also have certain resistance of E.coli activity.Endophytic fungi from bryophytes Penicillium sp.(No.L-7-2)rice medium,30 compounds were isolated from the communist party of China,including 11 alkaloids compounds(13-23),9 terpenoids(24-32),9 ketone compounds(33-41)and a nonsteroidal compound oxide(42),including package,seven new compounds(16 or 17 and 22-26).The results of cytotoxic activity tracing showed that compound 14 was the main reason for the cytotoxic activity of this strain,while compounds 18 and 42 also showed moderate cytotoxic activity.The anti-fungal and anti-inflammatory activities of the new compound were detected.The results showed that the new compound had NO effect on Candida albicans wild-type strain SC5314.Compound 17,22 and 23 showed moderate inhibitory effect on NO production in mouse macrophage RAW264.7 induced by lipopolysaccharide(LPS).Symbiotic fungus Aspergillus tubingensi(No.SQ10)from the earthworm of rice culture were gotten 11 ketone compounds(43-56),including three new compounds(43-45).The cytotoxic activities of compounds 43-45,48,55 and 56 were studied.Unfortunately,they did not show significant activity.The earthworm symbiotic fungus Hypocrea lixii(No.BQ3)has been fermented,and the crude extract of the earthworm fungus Hypocrea lixii(No.BQ3)has been detected to have certain cytotoxic activity.The IC50 of the crude extract against human prostate cancer cell PC3 and lung adenocarcinoma cell A549 were 7.2 and 6.7μg/mL,respectively,and constructed a visual molecular network visualization of crude extracts,Now get two compounds(57-58).In this paper,the chemical composition and biological activity of the secondary metabolites of five strains of microorganisms were studied,and some new secondary metabolites were found.Based on the above research results,it is suggested that we need to adopt certain biological technological means to further excavate the secondary metabolites of microorganisms.