ISSN:
1432-0614
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
Abstract Aspergillus niger IFO 8541 was found to be an efficient biocatalyst for the biotransformation of β-ionone into hydroxy and oxo derivatives. The reaction had to be carried out with an inoculum made of about 4×107 fresh spores/l and with a preliminary growth period giving at least 3 g/l biomass. The fungus developed in the form of pellets when cultivated as free mycelium; entrapment of the microorganism in calcium alginate beads was an efficient way to mimic this feature in an aerated, stirred bioreactor. The biotransformation was carried out using a fed-batch mode of operation involving sequential precursor addition. β-Ionone stopped the fungal growth and was converted into metabolites only when the carbon source remained present in the medium; it was fully oxidized after sucrose exhaustion. These conditions allowed recovery of about 2.5 g/l aroma compounds after 230 h cultivation with a molar yield close to 100%.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s002530050394