Chemical Analysis and Anti-MRSA Activity of Mat Extract from Aspergillus terreus VIT 2013

The growth parameters required for the growth and production of anti-MRSA metabolites of soil fungus Aspergillus terreus VIT 2013 was accomplished by partial optimization. Mass production of metabolites was carried out on malt extract broth (MEB) and metabolites were extracted by solvent extraction method. The mat extracts of Aspergillus terreus VIT 2013 showed high anti-MRSA activity. Further, purification of anti-MRSA fraction of mat extract, and analysis by GCMS revealed high amounts of pentamethyl ethanol followed by undecyl ester of dichloroacetic acid, mono (2-ethylhexyl) ester and 1, 2-benzenedicarboxylic acid. Its Minimum Inhibitory Concentration (MIC) was found to be 40 mu g against 10 isolates of MRSA. The MIC of standard vancomycin was assessed as 1.6 mu g for comparison. The extract was active against other MTCC isolates of gram positive and gram negative bacteria but no activity was seen against fungi. The 28S rDNA sequence results of Aspergillus terreus VIT 2013 was found to be 99% similar to Aspergillus terreus. GC-MS analysis of the ethyl acetate extract of the mat of Aspergillus terreus VIT-2013 suggests the presence of a compound which could be labelled as a broad spectrum antibiotic, active against MRSA and also several other pathogens.