Whole-cell bioconversion of vanillin to vanillic acid by Streptomyces viridosporus

Abstract

A two-step batch fermentation-bioconversion of vanillin (4-hydroxy-3-methoxybenzaldehyde) to vanillic acid (4-hydroxy-3-methoxybenzoic acid) was developed, utilizing whole cells of Streptomyces viridosporus T7A. In the first step, cells were grown in a yeast extract-vanillin medium under conditions where cells produced an aromatic aldehyde oxidase. In the second step, vanillin was incubated with the active cells and was quantitatively oxidized to vanillic acid which accumulated in the growth medium. Vanillic acid was readily recovered from the spent medium by a combination of acid precipitation and ether extraction at .96% molar yield and upon recrystallization from glacial acetic acid was obtained in .99% purity.

Oxidation of benzaldehydes to benzoic acid derivatives by three Desulfovibrio strains

“…In the presence of oxygen, oxidation of vanillin to vanillic acid was shown for Streptomyces viridosporus (47) and Serratia marcescens (45). The oxidation of vanillin to vanillic acid as an intermediate step in the degradation of trans-ferulic acid has been demonstrated for Pseudomonas fluorescens and Pseudomonas acidovorans (9,56).…”

Aldehyde oxidase carrying an unusual subunit structure from Pseudomonas sp. MX‐058

“…An oxygen-dependent aldehyde oxidase of microbial origin was first reported by Crawford and his coworkers (Crawford et al, 1982) in Streptomyces viridosporus, however, its enzymatic properties have not been fully investigated. The partially purified enzyme of S. viridosporus preferentially oxidizes vanillin and other aromatic aldehydes to the corresponding aromatic acids, but exhibits no preference for aliphatic aldehydes, and whole cells of S. viridosporus have been used for the oxidation of vanillin to vanillic acid (Pometto and Crawford, 1983).…”

Production of vanillic acid from vanillin by resting cells of Serratia marcescens

“…There is increasing interest in the use of whole-cell bioconversion processes in the synthesis of fine chemicals (4,15,16). Vanillin oxidation to vanillic acid by microorganisms has been known for many years (6), and recently this oxidation by whole-cell suspensions of Streptomyces viridosporus and Aspergillus japonicus has been reported (10,13). We report here such an oxidation with resting-cell suspensions of Serratia marcescens.…”

“…As far as we know this is the first report of a rapid and complete oxidation of vanillin to vanillic acid at a high substrate concentration (0.3%) by resting-cell suspensions, and the process may be commercially useful (2,7,8,14). Work is in progress to extend this transformation by S. nar(ces(ens to several other aromatic and aliphatic aldehydes, since the relaxed specificity of the involved enzymes should permit such an oxidation (6,13,15).…”