No abstract

This work is focused on the biotransformation of R-(+)-limonene and (-)-beta-pinene to bioflavor production. To carry out the present study, 405 microorganisms were tested for their ability to bioconvert the substrates. From the isolated microorganisms, 193 were selected in the prescreening using mineral medium for limonene degradation. At the screening step, eight strains were able to convert R-(+)-limonene and 15 to transform (-)-beta-pinene, both in alpha-terpineol. The highest concentration in alpha-terpineol from R-(+)-limonene was about 3,450 mg/L for Penicillium sp. isolated from eucalyptus steam. From (-)-beta-pinene, the highest product concentration of 675.5 mg/L was achieved using an Aspergillus sp. strain isolated from orange tree stem.

The main objective of this work is to present the optimization of the biotransformation of R-(+)-limonene and (-)-β-pinene aiming at the production of α-terpineol by strains of fungal and yeasts previously isolated by our research group using the methodology of experimental design. New optimized experimental data on α-terpineol production by the biotransformation of R-(+)-limonene and (-)-β-pinene using newly isolated microorganisms are reported in this work. Conversion of about 1,700 mg/L was achieved when R-(+)-limonene was used as substrate and the newly isolated strain 05.01.35 as microorganism at the central point of the experimental design, corresponding to a substrate concentration of 1.75%, mass of inoculum of 2 g, and substrate to ethanol volume ratio of 1:1. The same experimental condition led to higher conversions when (-)-β-pinene was used as substrates and the strains coded as 04.05.08 and 01.04.03 as microorganism. Here, conversions of about 770 mg/L were achieved.