Antioxidant and Antimicrobial Activity of Ophiocordyceps sinensis and Paecilomyces hepiali Extracts

Abstract

The paper deals with the study of two strains of medicinal fungi of the genus Ophiocordyceps sinensis and Paecilomyces hepiali, which were cultivated on two rice substrates – Oryza sativa L. var. indica and Oryza sativa L. var. japonica. For the methanol extracts prepared, the antioxidant activity was determined by the 2,2-diphenyl-1-picryl-hydrazyl free radical method. Extract (P. hepiali, Oryza sativa L. var. japonica) with IC₅₀ = 5.16 ± 0.01 mg ml^–1 was the most effective one in scavenging a stable radical. Testing the antibacterial activity against S. aureus and E. coli, the extract (O. sinensis, Oryza sativa L. var. indica) was found as the most effective to inhibit the growth of E. coli bacteria (250 % relative inhibition zone diameter). 1D and 2D NMR spectroscopy was used to identify chemical compounds in the six extracts prepared from two strains of O. sinensis and one strain of P. hepiali, which confirmed the presence of oleic acid, linoleic acid and urea in various ratios.