Study On Secondary Metabolites From Endophytic Micromonospora Sp. M66 Of Tripterygium Wilfordii Hook. F.

Bacteria of the genus Micromonospora run after Streptomyces as an important microbial source of natural products. Our work aims at the discovery of the secondary metabolites from endophytic Micromonospora sp. M66 of Tripterygium wilfordii Hook. f. which was isolated from Yunnan, China.Micromonospora sp. M66 was selected for the discovery of the secondary metabolites by chemical screening. Subsequently, fermentation conditions were optimized before fermentating this strain to get enough crude extracts. Isolation and purification of the secondary metabolites from Micromonospora sp. M66 were performed by means of chromatography(silica gel and reversed-phase silica gel column chromatography, Sephadex LH-20 column chromatography and high performance liquid chromatography). Finally, 11 compounds were obtained from the strain M66.Structures of 11 compounds were elucidated through spectroscopic analysis(mass spectroscopies and nuclear magnetic resonance spectroscopies).Compounds 1-11 were identified as 1H-Indole-3-carboxaldehyde(1), 1H-Indole-3-acetic acid(2), 3-hydroxyacetyl-indole(3), 3-(2,3-Dihydroxypropyl) indole(4), N-(1H-Indol-3-yl)-2-oxo-acetamide(5), 1HIndole, 3-[(5-methyl-2-pyrazinyl)methyl](6), 1H-Indole, 3,3’-[2,5-pyrazinediylbis(methylene)]bis-(7), Daidzein or 4H-1-Benzopyran-4-one, 6-hydroxy-3-(4-hydroxyphenyl)-(8), Genistein(9), 2-Acetamidobenzoic acid(10), 2-Hydroxy-3-methyl-quinoxaline(11).It was the first time to isolate and identify compound 3-7 and 11 from the genus of Micromonospora and indole derivatives 1-7 have never been isolated and identified from the same speices before, which exhibited the structural diversity of secondary metabolites from Micromonospora. Compound 2 was an important plant growth regulator. Compound 3 showed a notable growth inhibition of lymphocytic leukemia cell P388, Bacillus subtillis and Saccharomyces cerevisiae. Compound 6 exhibited a significant inhibiting activity against Staphylococcus aureus and compound 11 was able to interfere in the replication of HIV.