Biotransformation of R-(+)- and S-(?)-limonene by Fusarium oxysporum

摘要

In the past few years much work has been done on the biotransformation of limonene, an inexpensivehydrocarbon monoterpene, which is one of the most widely distributed terpene in nature. Recently, the strainF. oxysporum 152b has been selected based on its high production of extracellular alkaline lipase and otherpublications have also described the biotransformation of R-(+)-limonene into R-(+)-α-terpineol catalysed bythe same strain. The main characteristics of this conversion were described in recent papers but noinformation deals with the bioconversion of its isomer, S-(?)-limonene. Thus, this paper focused on thebiotransformation of S-(?)-limonene by F. oxysporum 152b, partially characterized and compared with thecharacteristics involved in α-terpineol production from R-(+)-limonene. In former studies, it was proven thatthe enzyme responsible for the production of α-terpineol by the biotransformation of R-(+)-limonene wasenantioselective and enantiospecific, has an intracellular nature and acts in anaerobic conditions. In thisstudy, it was observed that the production of limonene-1,2-diol from S-(?)-limonene has also an intracellularnature but it was higly influenced by an aerobic system and seemed to be cofactor dependent, consideringthat the product was not detected with an anaerobic biotransformation. The production of the intermediatelimonene-1,2-epoxide was not detected, indicating that the reaction proceeds mainly for the diol production.These results encourage further studies with this biocatalyst and the characterization of its enzyme systeminvolved in the biotransformation of S-(?)-limonene and other terpenes is of great importance, and could besource of novel aroma compounds with industrial interest.