Batch and Fed-Batch Production of β-carotene by Rhodotorula Toruloides KP324973 Using Corn Steep Liquor As Sole Carbon Source

Abstract Application of agro-industrial waste in microbial fermentation is interesting in economic and environmental aspects. Carotenoids production by Rhodotorula toruloides KP324973 was investigated using corn steep liquor (CSL) as sole carbon source. Haldane model with constants µmax = 0.056 h-1, KS = 1.54 vv-1%, and KI = 58.58 vv-1% showed best describe of cell growth kinetics on CLS. A same maximum carotenoid production rate (Rp) about 2.23 μg gcell-1 h-1 was obtained at initial CSL concentration of 5 v/v% after 72 h and 21 h in batch cultivation in shaken flasks and bubble column reactor (BCR), respectively. Further improvement of carotenogenesis was followed by fed-batch cultivation in BCR where the optimal setting of factors at feed flow rate of 5 mL h-1, pH of 5.66, and temperature 14 ˚C gained a highest Rp = 8.686 μg gcell-1 h-1. Chromatographic analysis showed more than 94% of produced carotenes was β-carotene.