Secondary metabolites produced by Macrophomina phaseolina, a fungal root endophyte of Brugmansia aurea, using classical and epigenetic manipulation approach

Endophytic fungi are rich sources of structurally complex chemical scaffolds with interesting biological activities. However, their metabolome is still unknown, making them appealing for novel compound discovery. To maximize the number of secondary metabolites produced from a single microbial source, we used the OSMAC (one strain-many compounds) approach. In potato dextrose medium, M. phaseolina produced phomeolic acid (1), ergosterol peroxide (2), and a volatile compound 1,4-benzene-diol. Incorporating an epigenetic modifier, sodium valproate, affected the metabolite profile of the fungus. It produced 3-acetyl-3-methyl dihydro-furan-2(3H)-one (3) and methyl-2-(methyl-thio)-butyrate (4), plus volatile chemicals: butylated hydroxy toluene (BHT), di-methyl-formamide, 3-amino-1-propanol, and 1,4-benzenediol, 2-amino-1-(O-methoxyphenyl) propane. The structure of compounds 1-4 was established with the help of spectroscopic data. This study revealed first-time compounds 1-4 in the fungus M. phaseolina using a classical and epigenetic manipulation approach.

Automated summary

Endophytic fungi are an important source of bioactive compounds with complex chemical structures. In this study, the metabolome of the fungus M. phaseolina was investigated to discover novel compounds. The OSMAC approach was used to maximize the production of secondary metabolites. The addition of sodium valproate, an epigenetic modifier, influenced the metabolite profile of the fungus and led to the discovery of new compounds.