This study investigated the production of antioxidant from Aspergillus candidus culture collection and research center 31543 in a fermentor. Scale-up production was performed according to the parameters optimized in shaking flask culture. Yields of ethyl acetate extracts of A. candidus broth filtrate (EAEAC) produced in 51 fermentor were 0.063% (w/v), which were higher than that in shake flask culture (0.041%, w/v). In the linoleic acid peroxidation system, there was no significant difference (P > 0.05) in the inhibition of peroxidation (IP%) between the EAEAC produced in fermentor and shake flasks. The IP% ( = 93%) of EAEAC obtained from the fermentor was higher than that of alpha-tocopherol and equal to that of BHA at 200 mug/ml. Both EAEAC produced in the fermentor and shake flask possessed similar components based on high-performance liquid chromatography profiles. (C) 2003 Elsevier Science Ltd. All rights reserved.