Due to its unique flavor and popularity, vanillin is considered as the most desirable flavoring substance on the market. Apart from an extraction of vanilla pod, natural vanillin can be prepared from isoeugenol (IG) by using isoeugenol-degrading microorganisms. In this study, filamentous microorganism designated as “strain IG1”was isolated from mineral medium supplemented with IG at 60C. Strain IG1is capable of degrading isoeugenol at a high temperature, a unique characteristic that has never been reported in the literature. Its slow growth rate, however, hinders further characterization of the strain. YCED medium (g/L: yeast extract 0.3, casamino acid 0.3, glucose 0.3 and K2HPO4 2) supplemented with 0.1% (v/v) isoeugenol was found to be the most appropriate medium for cultivating strain IG1. When isoeugenol was replaced with other intermediates of the isoeugenol epoxide-diol pathway (the only isoeugenol-degrading pathway reported thus far), strain IG1 was unable to utilize any intermediates other than isoeugenol. Therefore, it is most likely that strain IG1 may possess a novel isoeugenol-degrading pathway. The results from this study will allow researchers to further study the characteristic of strain IG1 in more detail.
Keywords: vanillin, isoeugenol-degrading microorganism