Microbial transformation 1,8-cineole

An interesting type of microbial transformation has been reported for 1,8-cineole (5) by a bacterium closely related to Pseudomonas flava. The bacterium was isolated from eucalyptus leaves and utilized 1.8-cineole as its only carbon source326. In shake cultures at least four compounds were produced however. 68% of the 1,8-cineole remained unreactcd. 

Microbial Transformation Products from 1,8-Cineole. The culture broth of A. niger cultured in the presence of 1,8-cineole (16, 1.5 g/1) for 7 days was extracted with ether. Gas chromatographic (GC) analysis of the extract revealed the formation of five products from 16. After the isolation of each products by column chromatography, 2-en 7o-hydroxycineole (17), 3-en 7o-hydroxycineole (20), 3-exo-hydroxycineole (21), 2-oxocineole (19) and 3-oxocineole (22) were identified from the interpretation of physico-chemical data (Figures 10 and 11) (18). All compounds were isolated as racemates. 

Figure 10. Microbial Transformation Products of 1,8-Cineole (16) by Pseudomonus flava 17).

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