title: Biotransformation of isoeugenol to vanillin by a newly isolated Bacillus pumilus strain: identification of major metabolites.
abstract: A bacterial strain S-1 capable of transforming isoeugenol to vanillin was isolated. The strain was identified as Bacillus pumilus based on biochemical tests, cellular fatty acid composition, riboprint pattern and 16S rRNA gene sequence analyses. In the biotransformation of isoeugenol, vanillin was the main product. With the growing culture of B. pumilus S-1, 10g l(-1) isoeugenol was converted to 3.75g l(-1) vanillin in 150 h, with a molar yield of 40.5% that is the highest up to now. Dehydrodiisoeugenol, a dimer of isoeugenol, was separated by preparative thin layer chromatography and identified by gas chromatography-mass spectrometry. Based on the accurate masses obtained from gas chromatography-high resolution mass spectrometry, two key intermediates, isoeugenol-epoxide (IE) and isoeugenol-diol (ID), were identified by mass spectra interpretations. The biotransformation with resting cells showed that vanillin was oxidized to vanillic acid and then to protocatechuic acid before the aromatic ring was broken. These findings suggest that isoeugenol is degraded through an epoxide-diol pathway.
authors.affiliation: Key Laboratory of Microbial Metabolism, Ministry of Education, College of Life Science & Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.
authors.forename: Dongliang
authors.initials: D
authors.lastname: Hua
authors.forename: Cuiqing
authors.initials: C
authors.lastname: Ma
authors.forename: Shan
authors.initials: S
authors.lastname: Lin
authors.forename: Lifu
authors.initials: L
authors.lastname: Song
authors.forename: Zixin
authors.initials: Z
authors.lastname: Deng
authors.forename: Zarao
authors.initials: Z
authors.lastname: Maomy
authors.forename: Zhaobin
authors.initials: Z
authors.lastname: Zhang
authors.forename: Bo
authors.initials: B
authors.lastname: Yu
authors.forename: Ping
authors.initials: P
authors.lastname: Xu
mesh_terms: D001407:Bacillus / Q000145:classification* / Q000378:metabolism*; D001426:Bacterial Proteins / Q000378:metabolism*; D001547:Benzaldehydes / Q000378:metabolism*; D001711:Biotransformation; D005054:Eugenol / Q000031:analogs & derivatives* / Q000378:metabolism; D013045:Species Specificity
chemical_list: D001426:Bacterial Proteins; D001547:Benzaldehydes; D005054:Eugenol; C036643:isoeugenol; C100058:vanillin