Antioxidant Potential of Penicillium citrinum and its Optimization through Different Statistical Approaches

Abstract

Three-step optimization strategies were applied to optimize the antioxidant potential of Penicillium citrinum. Primarily, different carbon and nitrogen sources were screened by classical methods, which revealed sucrose and NaNO₃ to be the most suitable. Significance of the components of Czapek dox’s medium with respect to antioxidant activity was evaluated with Plackett-Burman design, which supported sucrose and NaNO₃ to be the most significant. In second step, sucrose and NaNO₃ along with temperature were further taken as three variables for response surface methodology to study their interaction. Response surface analysis showed 4% sucrose, 0.05% NaNO₃ and incubation temperature of 35o C to be the optimal conditions. Under these conditions, the antioxidant potential assayed through different procedures was 90.1%, 70.9% and 70.1% scavenging effect for 1,1-diphenyl-2-picryl hydrazyl radical, ferrous ion and nitric oxide ion, respectively. The reducing power showed an absorbance of 1.35 with 65.5% activity for ferric reducing antioxidant power assay.