In-vitro Antimicrobial Studies of Isolated Myrothecium Spp Mrp001 against Human Pathogens

The isolated fungi Myrothecium spp MRP001 represent an important source of biologically active compounds. The maximum biomass production was optimized (pH 6.5, 96 h at 30 °C) using OFAT (one factor at time) in six different medias, After 96 h of growth, Tryptone Soya Broth (TSB) and Potato Dextrose Broth (PDB) shows maximum spore account (2×10 8 CFU/ml) of Myrothecium spp MRP001. Screening of biologically active metabolites obtained from 4-day old culture broth of the strain by Thin Layer Chromatography (TLC silica gel 60, 20 × 20, and 0.5 mm, Merck & Co, Inc) led to isolation of two fractions active against a wide variety of human pathogenic bacteria (Escherichia coli, Salmonella Typhi, Klebsiella pneumoniae and Bacillus cereus). The second active fraction was shows more antimicrobial activity and further purified by silica gel column chromatography. Among all the fungal extracts, methanol extract (6.5%) was found to have maximum extractive yield followed by the water (6.1%) and petroleum ether (5.7%) extract. The partially purified fraction exhibited good antimicrobial potential against human pathogenic bacteria using In-vitro plate assay. The purified metabolites were further concentrated using lyophilisation and 150 μg/ml dose confirmed to inhibit the growth of Escherichia coli, Salmonella Typhi, Klebsiella pneumoniae and Bacillus cereus respectively by MIC (Minimum Inhibition Concentration) test. The bio active metabolite was most stable at pH 7 and temperature 40 °C/30 min. These results are useful for further investigation of the fungus in the future for microbial disease treatment.