Secondary Metabolites Of Two Marine Actinomycetes And Their Bioactivities

Marine actinomycetes is a single cell, has complex morphological differentiation process and can produce a variety of secondary metabolites of ability of gram-positive bacteria In this paper, we selected 2 strains of different actinomycetes named 5003 and LJ25, among which 15 Actinomycetes was collected in the seawater from south china sea, by using the methods such as chemical separation and purification and antibacterial activity research.Filtered from 15 strains of Marine actinomycetes, we isolated 5003(AM6) and LJ25(AM6) which possess strong antibacterial activity. We expanded theirs fermentation to get extract and dry-mixed the extract with positive phase silica gel(100-200mesh) to get the sample, loaded the sample into glass chromatographic column, use chloroform-methanol as eluent, get eight fraction(Fr.A1-Fr.A8), merged Fr.A7 with Fr.A8 to get six and the fraction(Fr.B1-Fr.B6) by using gradient elution. The distillate Fr.B2-Fr.B5, combined with dry mix sample after loading using C18 reverse phase silica gel column, use acetonitrile-water as eluent, get seven fraction(Fr.C1-Fr.C7). Distillate Fr.C2-Fr.C5, purified through the Semi-preparetive HPLC(using C18 110 A, acetonitrile-water 40; 60) to get new compound 5003-A, 5003-B, 5003-C and four already known compounds, 5003-D, 5003-E,and 5003-F,5003-G, etc. According to the spectral data and literature, 5003-A, 5003-B, 5003-C of A and B marihysin respectively, marihysin C, 5003-D, 5003-E, and 5003-F, 5003-G, respectively cyclo(Ala-Ile), cyclo(Ala-Leu), cyclo(Ala-Tyr) and cyclo(Ala-the Asn). We PDA tested the RP-HPLC column(Inertsil ODS-SP5 um 4.6x150 mm) crude extract from the LJ25 strain. Expanded the fermentation culture to get the concrete and put into glass chromatographic column, with chloroform-methanol as eluent, resulted as eight fraction(Fr.A1-Fr.A8). Merged Fr.A7 with Fr.A8 and got six subfraction(Fr.B1-Fr.B6). Fr.B4-Fr.B6, loaded into C18 reverse phase silica gel column after combining with dry mix sample, use acetonitrile-water as eluent, got six fraction(Fr.C1-Fr.C6). Distillate Fr.C4-Fr.C6 merged, purified by the Semi-preparetive HPLC mathod,(using C18 110 A, acetonitrile-water 50; 50)to get compounds LJ25-A, LJ25-B and LJ25-C. According to the spectral data and literature, LJ25-A, LJ25-B and LJ25-C respectively bacillomycin La, bacillomycin Lb and bacillomycin Lc.We isolated 10 compounds-6 strains of indicator bacteria from the fermented liquid of actinomycetes 5003 and LJ25. Escherichia coli ATCC 25922, Aeromonas hydrophila ATCC 7966, Staphyloccocus aureus ATCC 29213, Bacillus subtilis, Micrococcus luteus, Bacillus thuringiensis bacteriostatic activity experiment was carried out. Among them, 5003-A activity against staphylococcus aureus, 5003-B, 5003-C, 5003-D, 5003-E, 5003-F,5003-G has the activity of Escherichia coli ATCC 25922,LJ25-A,LJ25-B,LJ25-C has a heavy moisture resistant active bacterium.