Substrate–fungus interaction on the enzymatic and non-enzymatic antioxidant activities of solid state fermentation system

he fungus–substrate interaction on the antioxidant activity of a solid state fermentation system (SSFS) was investigated employing two basidiomycete fungi: Pleurotus columbinus and P. floridanus and two ascomycetes: Aspergillus fumigatus and Paecilomyces variotii on powdered peels of banana, pomegranate and orange, empty pea pods and rice straw. The oven-dried substrates were moistened at 90% water holding capacity, inoculated with the test fungi and incubated at 25 °C for appropriate time. Culture extracts were tested for the enzymatic and non-enzymatic antioxidant activity. The effect of substrate on the antioxidant activity of the SSFS was stronger than that of the fungal species. Peroxidase (POX) activity was higher in the basidiomycetes than ascomycetes and achieved its maximum in P. floridanus versus complete absence in A. fumigatus. By contrast, catalase (CAT) activity was higher in the …