Cyclodextrin glycosyl transferase, a multifunctional extracellular enzyme used for the preparation of cyclodextrins, was produced by Bacillus cereus, an indigenous strain. Solid substrate fermentations with wheat bran and slurry fermentations consisting of 10% wheat bran were compared with submerged fermentations using defined nutrient medium. Solid state fermentation displayed the maximum activity of 59 units ml(-1) in 24 h when compared to slurry fermentation (58 units ml(-1)) and submerged fermentation (40 units ml(-1)). The use of wheat bran enhanced the activity by 50%. The promoting action of wheat bran was evident, with the supplementation of wheat bran extract in submerged fermentation resulting in 2.7-fold (110 units ml(-1)) higher activity in comparison to submerged fermentation.