Aspergillus niger JTS 191 was selected from many microorganisms tested as capable of converting ionones to other compounds having aromas. The individual transformation products from ,B-ionone were isolated and identifled by comparison with synthetically derived compounds. The major products were (R)-4hydroxy-f8-ionone and (S)-2-hydroxy-fl-ionone. 2-Oxo-, 4-oxo-, 3,4-dehydro-, 2,3dehydro-4-oxo-, 3,4-dehydro-2-oxo-, (S)-2-acetoxy-, (R)-4-acetoxy-, and 5,6epoxy-,8-ionone and 4-(2,3,6-trimethylphenyl)-but-3-en-2-one were also identified. Analogous transformation products of ,B-methylionone also were identified. Based on gas-liquid chromatographic analysis during the fermentation, we propose two main oxidative pathways of/3-ionone. The results of this study suggest that these transformations of,B-ionones may be useful as tobacco-flavoring compounds.

Muchattention has been paid to the aroma compounds formed by degradation of carotenoids in plants.:) In the previous paper, the usefulness of the microbial transformation for the preparation of these aromacompounds was demonstrated; jS-ionone was converted to more than 13 compounds containing (S)-2hydroxy-/?-ionone and (7?)-4-hydroxy-/?

No abstract

No abstract

Chemical studies on various essential oils of plant origin have revealed the occurence of numerous compounds with a trimethylcycl ohexyl group, presumably generated by the metabolism or degradation of carotenoids,1) which are decisively important in the quality and aroma of agricultural products such as black tea2) and tobacco.',"