STUDIES ON THE ANTIOXIDANT AND ANTIMICROBIAL ACTIVITIES OF PLEUROTUS OSTREATUS PSI101109 MYCELIUM

The antioxidant and antimicrobial potential of the ethanolic extract from Pleurotus ostreatus PSI101109 mycelium was determined based on inorganic and organic nitrogen sources in a culture medium. The presence of ammonium sulphate and corn extract resulted in a greater accumulation of bioactive compounds. The results were confirmed by the EC50 and minimum inhibitory concentration (MIC). The extracts of P. ostreatus PSI101109 mycelium selectively inhibited the strains used, both of which were of the genus Candida, at an MIC value of 12.5 mg ml(-1). The most resistant strains were found to be Escherichia coli and Listeria innocua. The capacity of the antioxidant was evaluated by the DPPH scavenging activity, beta-carotene-linoleic acid, the reducing power, the scavenging effect on superoxide radical, the scavenging effect on hydroxyl radical and the scavenging activity on nitric oxide. Compounds with antioxidant effects were present in the extracts. Lycopene was an exception because it was found to be lacking in values when culturation was performed in the presence of peptone and yeast extract, but had a maximum value on ammonium sulphate.