LIMONENE BIOTRANSFORMATION ABILITY BY BASIDIOMYCETES FROM THE BRAZILIAN AMAZON

R-(+)-limonene is the main component of the orange peel oil, which is available in large amounts, at low cost, and can be employed in biotransformation processes as a precursor of different value-added aroma compounds. Herein, was evaluated the biotransform potential of R-(+)-limonene by basidiomycetes that had been isolated from different sources found in the Amazon region, Brazil. The screening was performed using sixteen basidiomycetes (Agaricomycetes, Basidiomycota) belong to the working collection of the LabMicrA/UFAM (SISGEN: AC1746C). The fungal biotransformation was executed in flasks containing the substrate R-(+)-limonene in a mineral medium, which were further incubated at 28 °C on a rotary shaker (120 rpm) for 120 h. Samples of each culture were taken every 24 hours, extracted with ethyl acetate, and analyzed using gas chromatography–mass spectrometry with the National Institute of Standards and Technology database. In this study, only Pycnoporus sanguineus LabMicrA-1010 and Trametes elegans LabMicrA-1038 were considered potential candidates for limonene biotransformation, due to its capacity to use the R-(+)-limonene as the single carbon and energy source in a mineral medium, with the main products accumulated after 96 h of reaction. The compounds obtained were limonene 1,2-diol (54,1±0,6% and 42,6±0,7%) and limonene-1,2-epoxide (9,2±0,8% and 15,9±0,5%), respectively, and can be used as additives in food and cosmetics due to their biological activity. These derivatives were not detected in the controls. In the database of Merck Brazil in 2022, the values of limonene 1,2-diol are around R$ 193.08/g and R$ 719.53 for 3 g. The reference price of limonene-1,2-epoxide is around R$ 249.50 for 100 mL and R$ 1001.81 for 500 mL. whereas the reference price of R-(+)-limonene is about R$ 79.10/kg. These achievements are important and support the development of the production of natural aromas and demonstrate the potential of using these wild Amazonian fungi in biotechnological processes.