Production of 2-phenylacetic acid and phenylacetaldehyde by oxidation of 2-phenylethanol with free immobilized cells of Acetobacter aceti

Process Biochemistry 01/2004; 39(6):749-753. DOI: 10.1016/S0032-9592(03)00185-7

ABSTRACT Acetobacter aceti MIM 2000/28 was employed for the oxidation of 2-phenyl-1-ethanol. Oxidation in aqueous systems gave phenylacetic acid with high yields, while the use of a two-liquid phase system (composed of water and isooctane) allowed for the production of the corresponding aldehyde. Free cells showed poor operational stability and were immobilized in calcium alginate; immobilized cells had specific activity, substrate tolerance and stability higher than that obtained with free cells. Simple fed-batch operation with immobilized cells in an air-lift reactor allowed for the production of 23 g l−1 phenylacetic acid in 9 days without foam formation.

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