Preliminary Studies On Secondary Metabolites From A Tin Mine Tailings-Derived Fungus FE10007 Of Gejiu

In order to survive in the extreme environments with high pH, temperature, salinity and pressure, organisms have been found to develop unique defenses against these environments, leading to their synthesizing of novel molecules ranging from simple osmolytes and lipids to complex secondary metabolites. A microorganism is classified as an extremophile if it grows under conditions outside that which would have traditionally been considered life-supporting. Extreme-tolerant microorganisms can survive these harsh conditions, but grow best under more moderate conditions.The first extremophilic organism, which was thermophilic, was isolated in the 1860's. It was over a century later that it began to be widely accepted that there were a significant number of organisms capable of surviving in extreme environments, leading to a rapid growth in research in this area.In the paper, the secondary metabolites of strains, which were isolated from highly toxic soil of tin mine tailings dam in Datun, Gejiu, Yunnan Tin Co., Ltd., were studied. Firstly, a fungus FE10007 was selected for its rich secondary metabolites based on the TLC screening. It was preliminary identified as a strain belonging to Pestalotia clavispora. Then adaptable media and time for its fermentation were determined according to the optimization of fermentation conditions. Finally, the chemical constituents of its secondary metabolites were isolated and purified.11 compounds were identified based on their spectroscopic data. They are 6-(1-hydroxypentyl)-4-methoxy-5,6-dihydro-2H-pyran-2-one (1),6-(1-hydroxypentyl)-4-methoxy-2H-pyran-2-one (2),3-(hydroxymethyl)phenol (3),2-(hydroxymethyl) benzene-1,4-diol (4),2-(methoxymethyl)benzene-1,4-diol (5),3,4-dihydroxy-benzaldehyde (6),2,5-dihydroxybenzaldehyde (7),2,5-dihydroxy-3-methoxy-benzaldehyde (8),3-hydroxybenzoic acid (9),5-(hydroxymethyl)furan-2-carbaldehyde (10), and ergosterol (11). These 11 compounds are discovered from the secondary metabolites of Pestalotia clavispora for the first time.3-methoxybenzaldehyde (8) is a new natural product among them. These results exhibit that the diversity of structural types of secondary metabolites of tin mine tailings-derived fungus FE10007 is rich.