Biorredução de acetofenona por microrganismos do estado da Bahia

Abstract

The biorreduction has great importance in the production of optically pure substances and is widely used for asymmetric synthesis. Bioconversions occur with high specificity and efficiency because they are catalyzed by enzymes, forming one of the isomers from a pro-chiral substrate. This work had as main objective to evaluate the potential reduction of micro-organisms (yeasts, bacteria and fungi) isolated in the state of Bahia using as carbonyl substrate the acetophenone, analyzing its conversion into alcohol and identifying the enantiomeric excess produced. Strains of Saccharomyces cerevisiae isolated from sugar cane brandy distilleries of Bahia state, rhizobacteria isolated from Arachis pintoi (forage peanut) in southern Bahia and endophytic fungi isolated Hevea brasiliensis. The products were analyzed by gas chromatography coupled to mass spectrometry to verify the conversion of the substrate in alcohol and enantiomeric excess was determined by gas chromatography with chiral stationary phase. Of the 28 microorganisms evaluated 18 acted as biocatalysts. Products of reduction of acetophenone were obtained with yields between 6 and 79% and enantiomeric excess from 41 to 100%. Fungi CDC026, CDC086 and MDF077 converted acetophenone into (R)-alcohol, with ee of 54, 56, and 84%, while the other strains that showed positive results for acetophenone yielded the (S)-alcohol. Whereas 64% of test organisms were able to act as catalysts in the enantioseletive reduction of acetophenone, it was observed that the microbial diversity of the state of Bahia is a source of new catalysts for the production of enantiomeric pure compounds.