Optimization of growth medium and physicochemical parameters for high-yield biomass production and active metabolites from Aspergillus terreus

The selection of a nutrient medium and optimization of physicochemical parameters play a crucial role in the growth enhancement and production of bioactive secondary metabolites of fungi. The current study was to evaluate the influence of cultural conditions and physicochemical parameters affecting the growth and biomass production of Aspergillus terreus. Nutrient medium ((Potato dextrose broth, Czapek's Dox broth, Sabouraud dextrose broth, Potato Carrot broth and malt extract broth) in conjunction with physicochemical parameters such as temperature, pH, nitrogen sources, carbon sources, and salinity were assessed for optimal biomass production. The growth rate of the fungus was measured by determining the mycelial dry weight, and enhancement of antioxidant activity through DPPH scavenging potency in the culture broth. The highest growth rate of the fungus was observed in potato dextrose broth (PDB) compared to the other nutrient media at a significant level (p< 0.05). The present study demonstrated that PDB supplemented with cellulose and urea as carbon and nitrogen sources with a pH of 5.5 and 4% salinity at 28°C are the suitable conditions for maximal growth and biomass production. However, the antioxidants activity was at its peak level in PDA enriched with sucrose and ammonium sulphate at pH 5.5, and 7% salinity at 28°C. Thus, culture conditions, including nutrient components and physicochemical parameters play an important role in the growth rate A. terreus, to exploit the maximum yield for various biomedical applications.