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Several microorganisms were isolated from soil/sediment samples of Antarctic Peninsula. The enrichment technique using (RS)-1-(phenyl)ethanol as a carbon source allowed us to isolate 232 psychrophile/psychrotroph microorganisms. We also evaluated the enzyme activity (oxidoreductases) for enantioselective oxidation reactions, by using derivatives of (RS)-1-(phenyl)ethanol as substrates. Among the studied microorganisms, 15 psychrophile/psychrotroph strains contain oxidoreductases that catalyze the (S)-enantiomer oxidation from racemic alcohols to their corresponding ketones. Among the identified microorganisms, Flavobacterium sp. and Arthrobacter sp. showed excellent enzymatic activity. These new bacteria strains were selected for optimization study, in which the (RS)-1-(4-methyl-phenyl)ethanol oxidation was evaluated in several reaction conditions. From these studies, it was observed that Flavobacterium sp. has an excellent enzymatic activity at 10 °C and Arthrobacter sp. at 15 and 25 °C. We have also determined the growth curves of these bacteria, and both strains showed optimum growth at 25 °C, indicating that these bacteria are psychrotroph.

N,N-dimethylbenzenamine and N,N,3-trimethylbenzenamine were N-demethylated through enzymatic reactions mediated by whole cells of Aspergillus terreus strains SSP 1498, URM 3371 and URM 3571. The respective products, N-methylbenzenamine and N,3-dimethylbenzenamine, were obtained in high conversions under both neutral and basic conditions. The oxidative N-demethylation of tertiary aromatic amines by A. terreus was not enhanced by the presence of the oxidant tert-butylperoxide, although further demethylation of N,N-dimethylbenzenamine to aniline was observed. The strains of the investigated A. terreus were unable to perform the dealkylation of N,N-diethylbenzenamine.

Whole cells of hydrocarbon-degrading bacteria, isolated from polluted sediments in the Santos Estuary (Baixada Santista, São Paulo, Brazil), were able to catalyse oxidoreduction reactions with various substituted phenylethanols and acetophenones as substrates. A number of substituted phenylethanols were formed with high (>99 %) enantiomeric excess. The results of microbial oxidation of phenylethanols 2, 3, 5–7 by Acinetobacter sp. 6.4T and the reduction of acetophenones 1a–6a by Serratia marcescens 5.4T showed that the bacteria used as biocatalysts in this study present significant potential for exploitation in biotechnological processes. The reduction of prochiral acetophenones by Serratia marcescens 3.5T yielded optically active alcohols with 90–99 % enantiomeric excess, and Acinetobacter sp. 6.4T is a potential biocatalyst for the oxidation of alcohols.

The fungal strains Aspergillus terreus URM 3371 and A. terreus CCT 4083, isolated in Brazil, catalysed the deracemization of (RS)-1-[(4-methylselanyl)phenyl]ethanol (1) and (RS)-1-[(4-ethylselanyl)phenyl]ethanol (2). Different mass of whole fungal cells (1–5 g), pH values (4 and 7), biotransformation temperature (20 and 32 °C) and additives (ethanol, butanol, propanol and cyclohexanol) were employed in attempt to improve product yield and selectivity. The A. terreus strain URM 3371 transformed (RS)-1 into (+)-(R)-1 with high enantiomeric excess (e.e.≥98 %), good conversion (≥98 %) and acceptable yield (53 %).