Medium optimization for the production of antioxidants from Aspergillus candidus.

The objective of this study was to optimize the factors for the production of antioxidant from Aspergillus candidus CCRC 31543. Extracts of broth filtrate had higher antioxidant activity (inhibition of peroxidation [IP] >98%) when sucrose or lactose was used as a carbon source. Sucrose in the medium also resulted in a higher yield of extracts. Ethyl acetate extracts had the highest yield and antioxidant activity compared with the other two solvents. For the production of antioxidant, inorganic nitrogen sources were found to be more suitable than organic nitrogen sources, and ammonium sulfate was better than sodium nitrate. Yeast extract had a strong influence on the yield of antioxidant extracts. Both mycelium and broth filtrate of A. candidus CCRC 31543 showed similar antioxidant activity (IP = 95%), and they also had similar extraction yields.