Microbial Transformation of β -Ionone and β -Methylionone

Abstract

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.

Aerobic Palladium‐Catalyzed Oxidations in the Upgrading of Biorenewables: Oxidation of β‐Ionone and α‐Ionone

“…Allylic acetate 3 has previously been described as the product of microbial oxidation, the electrochemical oxidation of β‐ionone, and the lipase‐catalyzed trans ‐esterification of the corresponding alcohol that was obtained by the microbial oxidation of β‐ionone …”

“…Ketone 4 , which is a natural product with a pleasant floral scent, was previously synthesized by the palladium‐catalyzed arylation of 2,3,6‐trimethylbromobenzene with 3‐butene‐2‐one . A few examples in the literature have shown that ketone 4 can also be formed directly from ionones . The microbial oxidation of β‐ionone gave compound 4 in minor amounts, along with acetate 3 (in 1–2 % yield each) .…”

“…A few examples in the literature have shown that ketone 4 can also be formed directly from ionones . The microbial oxidation of β‐ionone gave compound 4 in minor amounts, along with acetate 3 (in 1–2 % yield each) . More recently, compound 4 was obtained in up to 65 % yield through the stoichiometric oxidation of α‐, β‐, or retro‐ionone with CuCl 2 , FeCl 3 , or substituted BQ (2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone) …”

Determination of the Reaction Yield during Biotransformation of the Volatile and Chemically Unstable Compound β-Ionone by Aspergillus niger

“…-Ionone stripping and chemical products synthesis were calculated using the above limiting mass transfer rate model (eqs [4][5][6]. Residual -ionone available for biotransformation was then deduced by difference between total precursor consumption and the sum of the amounts stripped and chemically degraded.…”

Microbial conversion of 4-oxoisophorone by Aspergillus niger.

“…The extract was analyzed by gas chromatography. 2) The substrate peak disappeared after 48hr and seven peaks appeared concomitantly with the decrease in the substrate (Fig. 1).…”